Обзор по материалам интернета
НЕАНДЕРТАЛЬЦЫ - ископаемые древние люди (палеоантропы), создавшие археологические культуры раннего палеолита. Скелетные остатки неандертальцев открыты в Европе, Азии и Африке. Время существования 200-28 тыс. лет назад. Как установили исследования генетического материала неандертальцев, они, видимо, не являются прямыми предками современного человека. Рассматриваются как самостоятельный вид "человек неандертальский" (Homo neanderthalensis), но чаще как подвид человека разумного (Homo sapiens neanderthalensis). Название дано по ранней находке (1856) ископаемого человека в долине Неандерталь, близ Дюссельдорфа (Германия). Основная масса останков неандертальцев и их предшественников «пренеандертальцев» (примерно 200 индивидов) обнаружена в Европе, главным образом во Франции, и относится к периоду 70-35 тыс. лет назад.
Неандерталец из Монте-Чирчео
Мальчик из грота Тешик-Таш
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Неандерталец из Ла-Шапель-о-Сен
Неандертальцы населяли преимущественно предледниковую зону Европы и представляли собой своеобразный экологический тип древнего человека, сформировавшийся в условиях сурового климата и некоторыми чертами напоминавший современные арктические типы, например, эскимосов. Для них были характерны плотное мускулистое сложение при небольшом росте (160-163 см у мужчин), массивный скелет, объемистая грудная клетка, чрезвычайно высокое отношение массы тела к его поверхности, что уменьшало относительную поверхность теплоотдачи. Эти признаки могли быть результатом отбора, действовавшего в направлении энергетически более выгодного теплообмена и увеличения физической силы. Неандертальцы имели крупный, хотя еще и примитивный мозг (1400-1600 см3 и выше), длинный массивный череп с развитым надглазным валиком, покатым лбом и вытянутым «шиньонообразным» затылком; очень своеобразно «неандертальское лицо» со скошенными скулами, сильно выступающим носом и срезанным подбородком.
Предполагают, что неандертальцы рождались более зрелыми и развивались быстрее, чем ископаемые люди современного физического типа. Возможно, что неандертальцы были довольно вспыльчивыми и агрессивными, если судить по некоторым особенностям их мозга и гормонального статуса, которые можно реконструировать по скелету. Есть и признаки постоянного давления стрессовых факторов, как, например, истончение зубной эмали, что, видимо, говорит и о плохом питании, и ряд других патологических признаков на скелете, часть которых можно объяснить жизнью в темных сырых пещерах. О неблагоприятном проявлении далеко зашедшей «силовой» специализации неандертальцев свидетельствует чрезмерное утолщение стенок костей длинных конечностей, что должно приводить к ослаблению кроветворной функции костного мозга и как следствие к анемии. Одностороннее силовое развитие могло происходить в ущерб выносливости. Рука неандертальца широкая, «лапообразная», с укороченными пальцами, с уплотненными суставами и чудовищными ногтями, вероятно, была менее ловкой, чем у современного человека. У неандертальского человека была высокая детская смертность, укороченный репродуктивный период и небольшая продолжительность жизни.
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В интеллектуальном отношении неандертальцы продвинулись достаточно далеко, создав высокоразвитую мустьерскую культуру (по названию пещеры Ле-Мустье во Франции). Только во Франции установлено свыше 60 разных типов каменных орудий; значительно усовершенствовалась их обработка: для изготовления одного мустьерского остроконечника требовалось 111 ударов против 65 при выделке ручного рубила раннего палеолита. <![if !vml]><![endif]>Неандертальцы охотились на крупных животных (северный олень, мамонт, шерстистый носорог, пещерный медведь, лошадь, бизон и др.), умели высекать и поддерживать огонь для обогрева жилищ. У них уже существовали некоторые ритуалы (культы, погребения), зачатки искусства, забота о соплеменниках (инвалиды, дожившие до пожилого возраста).
Неандертальцы, скорее всего, представляли вымершую боковую ветвь генеалогического древа гоминид; они часто сосуществовали с человеком современного типа в Передней Азии и некоторых районах Европы и могли с ним смешиваться. Но существует и другой взгляд на неандертальцев их считают возможными предками современного человека в отдельных регионах, например, в Центральной Европе, или даже универсальным звеном в эволюции от человека прямоходящего (Homo erectus) к современному человеку разумному (Homo sapiens). Однако работы 1990-х гг. по сравнению митохондриальной ДНК, выделенной из костей, найденных в Неандертале, с соответствующим генетическим материалом современного человека, говорят о том, что неандертальцы не являются нашими предками.
Около 35000 лет назад неандертальцы внезапно вымерли (сейчас стали известны более поздние стоянки неандертальцев, показывающие, что отдельные их группы "продержались" на захваченной кроманьонцами территории довольно долго - до 28 000 лет назад). Незадолго до этого в Европе появился современный человек (Homo sapiens sapiens). Возможно, между двумя этими событиями есть связь. Вот некоторые из самых древних находок современного человека (Кро-Маньон, Франция):
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В престижном научном журнале «Nature» опубликована статья российских, английских и шведских ученых, посвященная анализу ДНК неандертальцев. Самая, пожалуй, драматическая страница в истории происхождения современного человека — проблема неандертальцев. Споры об их судьбе и их вкладе в нашу кровь не прекращаются уже многие десятилетия.
«Мы, упрощенно говоря, видим разум современного человека, заключенный в теле древнего существа… У неандертальцев существовали верования, обычаи и обряды. Погребение мертвых, сострадание к себе подобным и попытки воздействовать на судьбу — вот новые аспекты, привнесенные в человеческую жизнь неандертальцами», — писал Ральф Солецки. «Под покатым лбом неандертальца горела истинно человеческая мысль» — мнение Юрия Рычкова.
И эти существа бесследно исчезли с лица планеты? Нет, многие антропологи помещают их среди наших предков. Следы первых неандертальцев датируются возрастом в 300 тысяч лет, а исчезли они где-то около 25 тысяч лет назад. И на протяжении по крайней мере 30 тысяч лет неандертальцы и наши прямые предки — кроманьонцы — жили бок о бок, в одних и тех же местах Европы (тут, вероятно, путаница с датировками - А.М.) Так почему бы им не смешиваться? — спрашивают сторонники нашего родства с неандертальцами. И все же в последнее время принято считать неандертальцев «боковой» ветвью эволюционного древа человека разумного.
Теперь результаты анализа образцов митохондриальной ДНК из ребер неандертальца подкрепляют эту точку зрения.
Несколько пояснений относительно методов анализа. Митохондрии (основной источник клеточной энергии) рассеяны вне ядра, в клеточной цитоплазме. В них находятся небольшие колечки ДНК, в которых помещаются около двадцати генов. Удивительна митохондриальная ДНК тем, что она передается из поколения в поколение принципиально иначе, чем хромосомная ДНК: только по женской линии.
Человек получает от отца и от матери по набору из двадцати трех определенных хромосом. Но то, какая из них наследуется от бабушки, а какая от дедушки, определяется случайно. Поэтому хромосомы у братьев и сестер несколько различны, и они могут быть не очень похожи друг на друга. А главное, по этой причине в ходе полового размножения между членами популяции происходит как бы «горизонтальное» перемешивание хромосом и возникновение различных новых генетических комбинаций. Эти комбинации и есть материал для эволюции, для естественного отбора. Иное дело — митохондриальная ДНК. Каждый человек получает мтДНК только от своей матери, та — от своей и так далее в ряду только женских поколений, которая имеет шанс передать ее и дальше.
И вот теперь учеными была проанализирована митохондриальная ДНК из костей скелета двухмесячного ребенка, найденного экспедицией Института археологии РАН в пещере Мезмайская на Кавказе. Отметим, что это самая восточная находка неандертальца, а жил он 29 тысяч лет назад. Из найденных ребер генетики сумели извлечь остатки генетического вещества ребенка и получили в результате отрезок мтДНК в 256 пар.
Что же показал анализ? Во-первых, «кавказская» мтДНК на 3,48 процента отличается от отрезка в 379 пар из костей коренного неандертальца из Германии, из долины Неандер, чей анализ был сделан еще в 1997 году. Эти различия невелики и говорят о родстве двух существ, несмотря на большое расстояние, разделяющее их, и время. Любопытно, что, по подсчетам ученых, немецкий и кавказский неандертальцы имели общего предка около 150 тысяч лет назад.
Но главное: этот отрезок очень сильно отличается от ДНК современного человека. В нем не удалось найти следов генетического материала, который мог бы быть передан от неандертальцев человеку современному.
Насколько надежным инструментом для изучения давнего прошлого служит анализ полученных с огромным трудом обрывков древних ДНК? — мой вопрос одному из авторов сенсационного открытия, Игорю Овчинникову.
«Довольно большой отрезок ДНК получить из древних останков нельзя. Возможно получить какое-то количество различных коротких фрагментов ДНК или получить большой фрагмент, совмещая перекрывающиеся отрезки. Тем не менее возможность для сравнения древнего и современного материала и филогенетического анализа, конечно, есть. Как правило, в такой работе для сравнения используются два высоко изменчивых участка в контрольном регионе митохондриальной ДНК человека, для которого проведены исследования на различных современных популяциях и известна примерная скорость появления мутаций. Отсюда появляется возможность построения филогенетического дерева, показывающего родство между разными популяциями и время их происхождения от общего предка».
Однако окончательную точку в споре о степени родства неандертальца и человека, на мой взгляд, все-таки не стоит ставить. Можно сравнивать мтДНК неандертальца с мтДНК не только современного человека, но и нашего прямого предка — кроманьонца. Правда, пока такой мтДНК еще не получено, но все впереди.
Возможно, существовали разные — генетически различавшиеся — группы неандертальцев, и какие-то из них все же были в числе наших предков.
Но все это не снимает драматизма ситуации: две параллельные ветви шли к светлому будущему цивилизации. И одна из них исчезает! Обстоятельства этого еще предстоит изучать и изучать.
Вот каким образом можно представить основные события в области исследований древней ДНК.
1984 год — получение и определение нуклеотидной последовательности ДНК из вымершего вида зебры квагга в лаборатории Аллана Вильсона в Калифорнии.
1985 год — клонирование и определение нуклеотидной последовательности из древней египетской мумии.
В последующие годы небольшие отрезки ДНК из древних останков тысячекратно умножались с помощью полимеразной цепной реакции — метода, который был разработан в 1985 году. Этот метод революционизировал молекулярную биологию и генетику, и авторы получили за него Нобелевскую премию. Получая множество копий исходного материала, исследователи заметно упростили себе работу.
1988 год — показана возможность анализа митохондриальной ДНК из образцов мозга человека давностью 7 тысяч лет.
1989 год — двумя группами в США показана возможность умножения древней митохондриальной ДНК.
1989 год — анализ митохондриальной ДНК сумчатого волка из Австралии, который вымер в прошлом веке.
1990 год — получен фрагмент ДНК из хлоропластов древних видов магнолии.
1992 год — получен фрагмент ДНК из ископаемого термита в янтаре.
Несколько позже начались главные работы по древним останкам человека. К наиболее интересным можно отнести:
1995 год — исследование митохондриальной ДНК из Тирольской мумии.
1997 год — исследование митохондриальной ДНК из останков неандертальца, найденного в окрестностях Дюссельдорфа в 1856 году.
Достаточно много исследований в последние годы было связано с изучением мумий из Северной и Южной Америки.
Если все предыдущие исследования были связаны с анализом митохондриальной ДНК, то в последние годы появились работы, связанные с анализом ДНК хромосом из древних останков человека.
1993 год — показана возможность определения пола в древних и средневековых останках человека.
1996 год — показана возможность изучения микросателлитов (коротких повторов) ДНК из средневековых останков. Эти два подхода крайне интересны антропологам и археологам для исследования половой и социальной структуры человеческих сообществ минувших времен.
Several Months ago, the publishers of National Geographic Magazine performed an experiment with computers and Neanderthal skulls that had been discovered in archaelogical sites in Europe. They took photographs of peoples faces today and applied them to computer-modeled Neanderthal skulls to get a general idea about what a Neanderthal may have looked like.
Before- This Is what the Original Subjects Looked like
After- This is the computer's image of Neanderthals
As you can see, A Neanderthal looked quite different from a modern human, with its low, sloping forehead, large brow ridge, and a large face with virtually no chin, it could be hard for some people to consider them to be closely related to humans. But if you look at the skulls here, you will notice many similarities between the Neanderthal skull in the center and the Cro-Magnon skull on the right, which itself in almost identical to the skulls of modern-day humans. Also, you will notice that the Neanderthal skull is very different from the primate skull on the left. The Neanderthal's is larger and slightly wider than both the Pithecanthropus and the Cro-Magnon. This allowed the Neanderthal to have a larger brain. In fact, The average brain size of a Neanderthal was larger than the average brain size of human today.
The skull of a Neandertal is shown here between that of Pithecanthropus (left) and Cro-Magnon (right).
In general, Neanderthals are thought to have been shorter than modern man, standing at about 5 ft. 5 inches, but stronger and adapted for better endurance. Since they lived in the Ice Age, Neanderthals are thought to be adapted for survival in extreme cold. With relatively short forearms and lower legs, heat loss was minimal. The life span of a Neanderthal was about 40 years. Discovered Neanderthal skeletons show that virtually all of them had suffered a broken bone at one time, and many had arthritis as they reached old age. Many have malformed tooth enamel, indicating periods of starvation. Indeed, their bodies were adapted to survive one of the most harsh climates in human history.
Today, many anthropologists studying Neanderthals have begun to examine more closely the culture and traditions of the Neanderthals. Because Neanderthals lived many thousands of years ago, their clothing and belongings have long since been abandoned and buried beneath the many layers of the Earth.
There are, however, a few possible ways to delve into the culture of the Neanderthals. One way to study early man's way of life is through cave art. <![if !vml]><![endif]>
Нижеследующий рассказ о неандертальском искусстве не заслуживает доверия. Тут явно какая-то путаница, причины которой (т.е. что с чем перепутал журналист) я пока не установил. Однако в настоящее время образцы подлинно неандертальской живописи науке неизвестны. Есть следы размазывания красителей (типа охры) по стенам пещер и окрашенные отпечатки ладоней; есть кость с просверленными дырочками ("флейта"; по некоторым предположениям - служила для добывания огня трением); есть ожерелье из зубов; наконец, совсем недавно обнаружено "скульптурное изображение" человеческой головы: http://news.bbc.co.uk/1/hi/sci/tech/3256228.stm
Откуда бы ни был взят рисунок, изображенный справа, это пока не признано официальной наукой как неандертальское искусство.
The Art Work that belongs to the Neanderthals can be found in caves located in Europe. Most of the art work is done in the form of drawings or sketches on cave ceilings and walls. These drawings often portray prehistoric animals or Neanderthal men. Sculptures of various size and shape can also be found in these caves. Many of these statuettes are in the shape of women, some pregnant. It is thought that the paintings and sculptures in the caves could have been made for entertainment. It has also been suggested that the motive behind the art was "hunting magic". That is, the Neanderthals may have believed that by drawing a picture of an animal that they intended to hunt and then stabbing the picture with a weapon, they would recieve luck during the hunt.
Another theory claims that the art represents a fertility cult in which certain animals represent males or females. This theory does not necessarily hold up considering that no sexual parts of the animals have ever been drawn on any of the cave walls that modern man has discovered.
Another distinct remnant of lost Neanderthal culture are burial tombs. The only known reason for humans to bury their dead is tradition. Where and when did this tradition begin? The burying of the dead probably began with the Neanderthals. There is plenty of evidence of the Neanderthal's concern for their dead, such as their buryal rituals which have been depicted in their artwork, and the goods which have been found in their gravesites, placed with the deceased, indicating a belief in an afterlife. The graves they made were small and shallow. The body often lay with bent knees. Found within many graves are what appear to be strewn wildflowers.
The culture of these "primitives" is very close to the very basic practices of society today. Whether in a burial site in Northern Iraq, or a cave with paintings in Germany, their traditions were accentual ingredients in forming the traditions that we modern humans hold so dear to our hearts.
Neanderthal Man survived through the Ice Age. They learned to make tools, and are thought to have had fire. They had a strong Culture, and possibly religious beliefs, indicated by their burying of their dead. Neanderthals lived side by side with modern humans for over 10,000 years. There are many theories on why the Neanderthals disappeared. Most of them involve Homo sapiens sapiens in one way or another, considering that the Neanderthal's extinction coincides with the early human's estimated arrival in Europe from their original home in Africa.
One theory states that the Neanderthals were killed off by modern humans. The Neanderthals may have reacted to the new humans as enemies. Since the modern humans are presumed to have been smarter than the Neanderthals, and since modern humans are still alive today, this theory concludes that fighting wiped the Neanderthals out. However, this theory does have its faults. First of all, why would two culture's begin to fight after many thousands of years of peaceful coexistance?
Also, it shows a lot of human arrogance to assume that early man could take an entire species that was stronger and almost as smart as them and fight it to extinction.
Another theory proposes that Neanderthals were wiped out by diseases introduced by the modern humans to which Neanderthal man was not immune. Although this theory is plausible, it is not probable, considering that the Neanderthals lived in close proximity to modern man for so long. Still, it is possible that there was a disease which caused the Neanderthals to die out.
The final theory states that Neanderthals and modern humans became one species, through thousands of years of interbreeding. Supporters of this theory state that some modern day Europeans have facial features similar to Neanderthal man. This doesn't prove the theory, however, considering that the features of modern humans differ greatly depending on geographical location, so that evidence is circumstantial. Critics of this theory state thathumans and Neanderthals would not interbreed under any circumstances. Ever. This is doubtful. Humans and Neanderthals lived together for thousands of years in the same area. It is very unlikely that there was never any interbreeding. It is very likely that the human and Neanderthal people had some contact with eachother, breeding and exchanging ideas. Neanderthal genes may have been inserted into the human gene pool, and Human genes may have been added to the Neanderthals. At this point, Neanderthals and humans may have evolved together at an incredible rate, becoming one race in a relatively short period of time. On the other hand, Neanderthals might have been cut off suddenly from contact with the humans, possibly by a disease, a war, or an increase in population causing the natural resources to be inadiquate for keeping so many hominids alive. No matter which theory you think is most plausible, until more discoveries are made, modern man will not know what became of our ancient companions. The mystery of the Neanderthal is still waiting to be solved.
Neanderthals and the Evolution of Language
(9 September 1999)
A topic of much debate is the date for the evolution of language. In part, there is a definitional problem: while vervets use vocal cries that share many of the characteristics of words, and bonobos (more so than chimpanzees) can be trained to communicate with signs. The female bonobo Kanzi, for instance, one of the primary subjects in E. Sue Savage-Rumbaugh's research, has demonstrated impressive symbolic abilities. In her SRCD Monograph, Savage-Rumbaugh has documented that Kanzi could comprehend more than 440 novel sentences of request and performed equal to or somewhat better than did a 2-1/2 yr old girl tested in the same manner and with the same sentences. Kanzi's language production was assessed by Patricia Greenfield of UCLA at the level of a 1-1/2 yr old child. (Contact: Sue Savage-Rumbaugh and Duane Rumbaugh <LRCDMR@langate.gsu.edu>.)
This of course still leaves a considerable distance between the linguistic capabilities and performance of human beings and that of our closest relatives. However, it is not in principle difficult to imagine forms of speech intermediate to ours in complexity; for instance, speech with a reduced set of phonemes, grammatical categories, and sentence forms. The difficulty is determining what kinds of evidence are relevant to this question, and how to evaluate the scarce clues available to us.
Cultural evidence. It is no doubt the case that achaeological remains of culture can tell us something about the cognitive abilities of the people in question. However, in order to interpret the cultural remains, we need a theory of how various cognitive abilities enable (and are required to account for) certain cultural activities. At present, there is no clear consensus on such a theory. In the context of language, we specifically need a model of how the biological and cultural innovations of language - and they must of necessity go hand in hand - impact our cognitive skills. Is it for instance the case, as Merlin Donald (1991) argues, that human beings today can function very well without language, retaining their abilities to interpret events, interact socially, plan their days, and communicate through a range of mimetic means? Or, on the contrary, are human minds generated by language in a radical way, so that deprived of language, we descend to the cognitive skills of chimpanzees? This view might be suggested by the apparently severely reduced cognitive capacities of children raised by animals. It is also a view that resonates with the idea that human beings are caught in the "prison-house of language" (Nietzsche), depending for their basic cognitive skills on the culturally constructed nature of language.
In my view, it is fruitful to examine the cognitive abilities associated with the imagination as more fundamental to advances in human cognition than language per se. Such advances are required for the emergence of certain forms of language, notably those that do not refer directly to what is present. Thus, evidence of imagination can be taken as a minimal requirement for language as internal thought. However, the converse does not necessarily hold: internal thought does not appear to require language.
The hyoid bone. Evidence that Neanderthals had a morphologically near-modern vocal apparatus is presented in Arensburg, B., Tillier, A.M., Vandermeersch, B., Duday, H., Schepartz, L.A. and Rak, Y. (1989). A middle palaeolithic human hyoid bone. Nature 338: 758-760. It is depicted to scale in Donald C. Johanson and B. Edgar's From Lucy to Language (Simon and Schuster, 1996), p. 107. For a discussion, see Arensburg, B., Schepartz, L.A., Tillier, A.-M., Vandermeersch, B., Duday, H. & Rak, Y. (1990) A reappraisal of the anatomical basis for speech in Middle Palaeolithic hominids. American Journal of Physical Anthropology. 83. 137-46. See also Arensburg, B. & Tillier, A.-M. (1991) Speech and the Neanderthals. Endeavour. 15 (1). 26-8.. For background, see Aiello and Dean's An Introduction to Human Evolutionary Anatomy, p. 243.
The hypoglossal canal. Kay, Cartmill, and Balow at Duke have recently measured the relative size of the hypoglossal canal in primates. This canal, a hole at the base of the skull in the area where the spinal cord enters the head, is the conduit for the nerve fibers from the brain to the muscles of the tongue, and an interesting index of complex speech. See the Duke University press release (external) and John Wilford's presentation of the results in The New York Times, April 28, 1998. In brief, the findings indicate that the enlargement of the hypoglossal canal to modern proportions happened already in early forms of archaic homo sapiens around 400,000 years ago. Neanderthals show the same-sized canal and according to this line of evidence would have possessed complex speech. Because of their shorter neck, their range of vowels may have been narrower. More recently, this line of reasoning has been challenged; cross-species comparisons suggest the hypoglossal canal may not be a meaningful indicator of adaptations for speech. See Kay et al. (1998).
Contact: Matt Cartmill, Biological Anthropology and Anatomy, Duke University, NC.
For evidence that the Neanderthal were poor at cultural innovation, yet capable of acquiring novel technology from their Homo sapiens sapiens neighbors, see Paul Mellars, The Neanderthal legacy: an archaeological perspective from western Europe (Princeton, NJ: Princeton University Press, 1996).
While scientists agree that speech is probably the most important behavioral attribute that distinguishes human beings from other animals, they have been at a loss to determine when and how that transforming evolutionary step occurred.
They have probed the human brain and compared it with casts of the braincase from ancient fossil skulls. They have compared bones and muscle attachment points in the throats of humans, apes and ancestral human skeletons. Archeologists have examined patterns in early stone tools for clues to when humans might have developed the creativity and the self-awareness usually associated with communication skills like speech.
All they had been able to agree on is that the earliest unambiguous evidence for human speech is found in the cave art and other artifacts, particularly in Europe and Africa, that began appearing some 40,000 years ago.
Now scientists at Duke University have explored a new avenue of fossil anatomy and found surprising evidence suggesting that vocal capabilities like those of modern humans may have evolved among species of the Homo line more than 400,000 years ago. By then, their research shows, human ancestors may have had a full modern complement of the nerves leading to the muscles of the tongue and so could have been capable of forming speech sounds.
The new findings, moreover, indicate that the Neanderthals, relatives of modern humans, could have had the same gift for speech. Their extinction about 30,000 years ago has often been attributed in part to speech deficiencies, restricting their ability for cultural innovation.
In a report being published Tuesday in The Proceedings of the National Academy of Sciences, the Duke anthropologists say that if their interpretation of the tongue nerves is correct, "then humanlike speech capabilities may have evolved much earlier than has been inferred from the archeological evidence for the antiquity of symbolic thought."
The research was conducted by Dr. Richard F. Kay and Dr. Matt Cartmill at the Duke Medical Center in Durham, N.C., with the assistance of a former student, Michelle Balow. The results were also described earlier this month in Salt Lake City at a meeting of the American Association of Physical Anthropology.
"This is evidence for the proposition that Neanderthals could talk," Cartmill said in a telephone interview on Sunday. "Did they sound like modern humans? I don't know."
Anthropologists familiar with the research said the findings were interesting and exciting. Some were reserving judgment, but not Dr. Erik Trinkaus, an anthropologist at Washington University in St. Louis, who specializes in Neanderthal studies.
"I think it's not only a reasonable conclusion," he said, "but one long overdue."
Trinkaus said previous research had been based on deficient anatomical reconstructions, none of which adequately took into account the neurological aspects for controlling the vocal track to allow for speech. As for the possibility of speech by archaic Homo sapiens 400,000 years ago, even before Neanderthals, he said this was consistent with a significant enlargement of brain size in that period, the appearance of a more complex tool technology and migrations into colder climates, where life probably depended on greater planning that could be related to advances in communications skills.
On the other side, Dr. Philip Lieberman of Brown University, an authority on early language, has argued that the Neanderthal throat would not have been well suited for the production of the vowels a, i and u. But Trinkaus contended that a species would not have needed modern English's range of vowels to have speech and language.
Even the discovery in Israel a decade ago of a Neanderthal skeleton with a large hyoid bone, which is in the throat and associated with speech, had not settled the issue of Neanderthal speech. Scientists had said there was still insufficient fossil evidence to enable an understanding of how the large hyoid bone might have influenced the production of vocalizations.
Cartmill himself cautioned that the new evidence for earlier human speech "is suggestive but, in the present state of our knowledge, it is not proof."
Other scientists noted that other, independent evolutionary developments, including a lengthened larynx, enlarged prefrontal brain lobes and some reconfigurations of the brain, would have been critical to the emergence of speech. The size of the brain of Neanderthals was well within the range of that of modern humans.
The Duke scientists directed their research at the hypoglossal canal in all primates. It is a hole at the bottom of the skull in the back, where the spinal cord connects to the brain. Through the canal run nerve fibers from the brain to the muscles of the tongue.
It occurred to the scientists that the size of the hypoglossal canal might serve as an index of the vocal abilities of modern and early humans. The wider the canal, they assumed, the more nerve fibers there could be to control the tongue muscles. And the more nerves, they further suggested, the finer control the species could have over its tongue for the purpose of making speech sounds.
On the basis of comparative measurements of hypoglossal canals of modern humans, apes and several human ancestor fossils, the researchers concluded that the canals of modern humans are almost twice as large as those of modern apes -- the chimpanzee and the gorilla -- which are incapable of speech. They also found that the canal size of austrolopithecines, earlier human relatives
that died out about one million years ago, did not differ significantly from that of chimpanzees.
The results, the scientists reported, "suggest minimum and maximum dates for the appearance of the modern human pattern of tongue motor innervation and speech abilities."
To narrow the range, the scientists examined skeletons of Neanderthals and also of species of the Homo genus that lived as much as 400,000 years ago. These included Kabwe specimens from Africa and Swanscombe fossils from Europe. Their hypoglossal canals fell within the range of those of modern Homo sapiens.
"By the time we get to the Kabwe, about 400,000 years ago, you get a canal that's a modern size," Cartmill said. "And that's true of all later Homo species, including Neanderthal."
Tuesday, April 28, 1998
Copyright 1998 The New York Times
IGOR V. OVCHINNIKOV, ANDERS GЦTHERSTRЦM, GALINA P. ROMANOVA, VITALIY M. KHARITONOV, KERSTIN LIDЙN & WILLIAM GOODWIN
Molecular analysis of Neanderthal DNA from the northern Caucasus
Nature 404, 490 - 493 (2000)
© Macmillan Publishers Ltd.
The expansion of premodern humans into western and eastern Europe 40,000 years before the present led to the eventual replacement of the Neanderthals by modern humans 28,000 years ago. Here we report the second mitochondrial DNA (mtDNA) analysis of a Neanderthal, and the first such analysis on clearly dated Neanderthal remains. The specimen is from one of the eastern-most Neanderthal populations, recovered from Mezmaiskaya Cave in the northern Caucasus. Radiocarbon dating estimated the specimen to be 29,000 years old and therefore from one of the latest living Neanderthals. The sequence shows 3.48% divergence from the Feldhofer Neanderthal. Phylogenetic analysis places the two Neanderthals from the Caucasus and western Germany together in a clade that is distinct from modern humans, suggesting that their mtDNA types have not contributed to the modern human mtDNA pool. Comparison with modern populations provides no evidence for the multiregional hypothesis of modern human evolution.
A Breed Apart
DNA Tests: Humans Not Descended from Neanderthals
By Kenneth Chang
March 28— DNA from the bones of a Neanderthal baby who died 29,000 years ago offers further evidence that Neanderthals are cousins rather than ancestors of modern humans.
Writing in Thursday’s issue of the journal Nature, William Goodwin of the University of Glasgow in Scotland, along with collaborators from Russia and Sweden, report that the baby’s DNA is much more similar to another Neanderthal DNA sequence reported in 1997 than to that of modern humans.
Evolution or Replacement?
Some anthropologists have argued that people evolved at least partly from the Neanderthals. The opposing theory is that modern humans evolved in Africa, then spread outward, overwhelming earlier hominids including Neanderthals. The short, squat Neanderthals inhabited much of Europe from about 100,000 years ago until dying out about 28,000 years ago.
"Neanderthal DNA is distinct from modern humans," Goodwin says, "and there are no examples of humans having Neanderthal-type DNA."
The shaded area indicates the known range of Neanderthals. Mezmaiskaya is the location where the baby Neanderthal whose DNA was sequenced was found. An earlier Neanderthal DNA sequence was determined from bones found in Feldhofer Cave in Germany.
The researchers isolated segments of DNA from the baby’s mitochondria — small, energy-producing bodies within a cell that contain their own genetic code separate the main DNA strand in the nucleus of the cell. Mitochondrial DNA is easier to study, because each cell contains about 1,000 mitochondria, meaning there are about 1,000 times more DNA strands to extract. Unlike cell DNA, mitochondrial DNA is inherited only from the mother.
Not Human Enough
The baby’s mitochondrial DNA differed from that of the other Neanderthal in 3.5 percent of the locations tested, while the divergence from humans was 7 percent. Scientists consider that to be a substantial gap. "It all points away from the Neanderthal," Goodwin says.
Based on the number of differences, and the expected rate of change, Neanderthals and humans last shared a common ancestor about 500,000 years ago, the researchers say.
The Neanderthal DNA was also no more similar to the DNA of Europeans than people elsewhere, which might have been expected if Neanderthals had mated in large numbers with their human neighbors in Europe.
The baby, found in Russia’s Caucasus Mountains, has been estimated in age at somewhere between an unborn 7-month-old fetus and a newborn of a couple of months. Molecular biologist Matthias Hoss, an expert in ancient remains now working at the Swiss Institute for Cancer Research, said the research appears to support the theory that Neanderthals were an evolutionary dead end.
"This adds quite a lot of confidence that the Neanderthal didn’t contribute to modern populations," he said.
Krings, M; Stone, A; Schmitz, R W; Krainitzki, H; Stoneking, M; Paabo, S.
Neandertal DNA sequences and the origin of modern humans
Cell 90 (1997): 19-30.
Authors' abstract: DNA was extracted from the Neanderthal-type specimen found in 1856 in western Germany. By sequencing clones from short overlapping PCR products, a hitherto unknown mitochondrial (mt) DNA sequence was determined. Multiple controls indicate that this sequence is endogenous to the fossil. Sequence comparisons with human mtDNA sequences, as well as phylogenetic analyses, show that the Neanderthal sequence falls outside the variation of modern humans. Furthermore, the age of the common ancestor of the Neanderthal and modern human mtDNAs is estimated to be [around 600,000 years, or] four times greater than that of the common ancestor of human mtDNAs . This suggests that Neanderthals went extinct without contributing mtDNA to modern humans.
November 08, 1999
The Latest Neanderthal
New evidence indicates that Neanderthals roamed central Europe far more recently than researchers thought
By Alan Hall
Image: Northern Ilinois University
HOME SWEET HOME. Vindija cave in Croatia was inhabited by Neanderthals as recently as 28,000 years ago.
Theories abound about the fate of the Neanderthals. The most common picture painted by researchers is that they were not quite as bright as modern man (even though they had larger brain cavities), were rather brutish and were driven to extinction by the more facile and nimble modern Homo sapiens who flooded into Europe from Africa. Far from intermarrying or trading with their newly arrived cousins, the stocky, thick-browed Neanderthals may even have been slaughtered by them. As the story goes, the last few Neanderthals huddled in caves on Europe's Iberian Peninsula during the last great Ice Age and disappeared quietly about 34,000 years ago.
Image: Hunterian Museum
COMPARATIVE ANATOMY. Neanderthal skull(top) is characterized by thick brow ridges and a low sloping forehead. Those of modern humans (bottom) are thinner and more rounded with a higher forehead and a projecting chin.
But new findings from a cave in Vindija, Croatia, combined with other recent discoveries, may upset some scholars' hereditary applecarts. In a paper published in the October 26 issue of the Proceedings of the National Academy of Sciences, a team of investigators report that the most recent remains found in the Vidija cave, which is located about 34 miles north of the Croatian capital of Zagreb, indicate that Neanderthals and modern man must have coexisted in central Europe for at least six millennia. "Most scientists would have expected to find the latest Neanderthal in southwest Europe, rather than in central Europe," said paleontologist Fred H. Smith, a research team member and chairman of the anthropology department at Northern Illinois University.
Using direct accelerator mass spectrometry radiocarbon dating, team member and colleagues at the University of Oxford in England determined that two pieces of Neanderthal skulls from the Vindija site are between 28,000 and 29,000 years old, compared with the most recent findings of 33,000 to 34,000 years for Neanderthal remains found in Spain.
Other findings from Vindija are even more intriguing. It appears that the two groups, at the very least, traded with each other--and may even have interbred. For example, Neanderthals are commonly associated with stone tools, while early modern humans made more sophisticated stone and bone tools. But those unearthed at Vindija were both kinds of tools, including a beveled bone probably used as the tip of a spear. "The big question is: 'Why do we have a combination of tools?' " Smith says. "It's possible Neanderthals developed all these tools or got the bone tools through trade with moderns." Both possibilities run counter to the generally accepted idea that Neanderthals could not produce implements from bone or use more sophisticated stone and bone tools.
In earlier work, Smith also argued that late Neanderthal fossils from the Vindija cave had some modern human anatomical characteristics. These conclusions also reinforce findings published by another team member, Erik Trinkaus, an anthropologist at Washington University in St. Louis. Last June, Trinkaus and European colleagues described the fossil of a 24,500-year-old early modern human child unearthed in Portugal. They observed that it had distinctive Neanderthal characteristics--an indication of interbreeding.
Image: Neanderthal-- A Cyber Perspective
BEAST. Idea that Neanderthals were ape-like brutes prevailed for nearly 50 years.
Moreover, the new Croatian dates indicating thousands of years of coexistence between Neanderthals and early modern humans in central Europe cast in a different light a study in which scientists compared the DNA of a Neanderthal with the DNA of contemporary humans. Published two years ago, the study concluded that, while Neanderthals and early modern humans may have coexisted in Europe, they probably didn't mate.
"The new dates, in my opinion, add some support to the idea that there was probably a good deal of genetic exchange between Neanderthals and modern humans," Smith said. "When you look at the anatomy of early modern Europeans, you also find a number of features that are hard to explain unless you allow the Neanderthals some ancestral status."
So, once again, new facts are changing the way we look at the past. The first depictions of Neanderthals shortly after the prototypical specimen was dug up in Germany's Neander Tal gorge in 1856 were definitely not the kind of person that you'd want in your neighborhood. A 1909 depiction based on the examination of a complete skeleton by the French paleontologist Marcellin Boule showed a stooped, club-carrying brute. Recent reconstructions show that they weren't really much more apelike than the early modern humans, who began appearing in Europe about 30,000 years ago.
In addition, it appears that the average Neanderthal was a skilled hunter and possessed a sophisticated kit of stone-flake tools with which he certainly made other wooden implements like spears. In the midst of a fearsome ice age he adapted well to the cold conditions and was adept at fire making and cooking. And judging from floral offerings in deliberate burial sites he may even have had some concept of the hereafter.
"The extinction of the Neanderthals by early modern humans, whether by displacement or population absorption, was a slow and geographically mosaic process," Trinkaus observes. "The differences between the two groups in basic behavior and abilities must have been small and rather subtle."
A visit to a Neanderthal home
By Kate Wong
From Croatia's capital city, Zagreb, Vindija cave is about a 90-minute drive through the rolling, rugged terrain of a northwestern region known as the Hrvatsko Zagorje. Today quaint cottages dot the countryside, the dwellings of farmers who coax corn and cabbages from the rocky soil. Thousands of years ago, however, Neanderthals inhabited these hills, and I have come to visit this cave that some of them called home.
The roads narrow as paleontologist Jakov Radovcic of the Croatian Natural History Museum and I approach Vindija, and the last 100 or so meters (about 330 feet) to the site have to be traversed on foot. "They chose a place near a spring," he observes, acknowledging the sound of trickling water that greets us as we step out of the car. A rock-strewn trail takes us into the woods and up a steep hill. Through the trees the landscape below is visible for a considerable distance. "The Neanderthals were trying to control the region," Radovcic remarks, adding that other Neanderthal shelters in Croatia bear similar strategic profiles: all are elevated, with a proximal water source.
The cave mouth opens an impressive 15 meters wide and 15 meters high. But it is only once I'm inside, after my eyes adjust to the darkness, that I realize how vast the space is--the cave stretches 50 meters deep, swelling in height and width. Along one wall unexcavated sediments display the stratigraphy of the site; the banded layers tell a color-coded story of glacial and interglacial periods.
Image: Kate Wong
VINDIJA CAVE in Croatia sheltered Neanderthals 28,000 years ago, the most recent ones known.
Radovcic draws my attention to a grayish green band, the so-called G3 level that contained some of the Neanderthal fossils he himself unearthed, and fishes a cast of one of the ancient bones out of his pocket. "The Vindija hominids were modernized Neanderthals," he says, showing me the partial lower jaw featuring the beginnings of a chin--one of the hallmarks of modern human morphology. And although other fossils from the site reveal typical Neanderthal traits such as the pronounced browridge, they are more delicate and modern in shape in the Vindija people than in earlier Neanderthals. Radovcic and others who have studied these remains believe this apparent shift toward the modern condition suggests interbreeding between Neanderthals and moderns--a case that is strengthened by early modern human fossil finds from central Europe that bear some Neanderthal-like features. (Many researchers, however, maintain that the two groups did not exchange genes. To them, these similarities simply reflect convergent evolution.)
Vindija has also yielded intriguing bone and stone tools, found in association with the Neanderthal fossils, that exhibit a sophisticated workmanship broadly characteristic of early modern humans. But whether these tools were discovered in their original contexts is the subject of debate: the seasonal freezing and thawing of the ground may have mixed the layers up, or denning cave bears may have disturbed the remains. If in fact Neanderthals made the more advanced tools, many archaeologists might have to rethink the evolution of these cultural traditions and reconsider who originated such modern human behavior. (Exactly how the October announcement by scientists that Neanderthal bones found in a French cave exhibit evidence of cannibalism affects the cultural picture is unclear.)
Unfortunately, a recent attempt to date directly the most modern-looking tool--a split-base bone point from the younger G1 level--has failed, according to a report in the October 26 Proceedings of the National Academy of Sciences USA. Despite that disappointing result, the international team succeeded in dating the G1 Neanderthals. Previously, a date from an associated cave bear bone had implied that these remains were 33,000 years old, but the new dates, taken directly on the human fossils, reveal that Neanderthals persisted in Croatia as late as 28,000 years ago, making them the most recent ones known from anywhere in Eurasia.
"We had known that Neanderthals existed until around 30,000 years ago in southwestern France and the Iberian Peninsula," says team member Fred H. Smith, a paleoanthropologist at Northern Illinois University. That they still lived in central Europe 28,000 years ago, he remarks, "suggests to me that the interaction between Neanderthal populations and modern humans was a lot more complex than we thought--it wasn't just a matter of pushing the Neanderthals out of the way."
Whether they warred with moderns and ultimately lost, or were peacefully absorbed into the population, the debate over how human the Neanderthals really were continues. But as I stood inside Vindija cave looking out, sheltered from an afternoon shower, I couldn't help thinking that 28,000 years ago a Neanderthal might have rested here on a drizzly day in late summer and savored the quiet, verdant beauty.
January 29, 2001
The Modern Human Origins Morass
Recent studies support a controversial theory of human evolution
By Kate Wong
When it comes to explaining the emergence of modern humans, researchers generally subscribe to one of two hypotheses. The Out of Africa theory holds that Homo sapiens burst onto the scene as a new species around 150,000 to 200,000 years ago in Africa and subsequently replaced archaic humans such as the Neandertals. The other model, known as multiregional evolution or regional continuity, posits far more ancient, diverse roots for our kind. Proponents of this view believe that Homo sapiens arose in Africa some two million years ago and evolved as a single species spread across the Old World, with populations in different regions linked through genetic and cultural exchange. Of these two models, Out of Africa has found favor with the majority of human evolution scholars. Just this month, however, results of two studies have come out that appear to support multiregionalism, adding new fuel to the long-standing debate.
Although the Out of Africa model was originally developed based on fossil evidence, it has gained popularity in part because so much genetic research seems to back it. The vast majority of these studies have focused on DNA from living populations. But in 1997 ancient DNA expert Svante Pддbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his colleagues reported in the journal Cell that they had retrieved and sequenced for the first time mitochondrial DNA (mtDNA) belonging to a Neandertal.
The team found that the difference between the Neandertal and modern mtDNA was more than three times that observed between any two living humans. Moreover, the Neandertal DNA didn't show any special similarity to DNA from living Europeans, which one might expect if the Neandertals, who occupied Europe for more than 200,000 years, contributed to the modern human gene pool. For many researchers, the Cell study put a serious, if not fatal, dent in the multiregionalists' argument that Neandertals were among our ancestors. And last year DNA from two other Neandertal specimens yielded similar results, further strengthening the Out of Africa replacement case.
Critics of the Neandertal DNA data, however, noted that without equally ancient samples from anatomically modern humans for comparison, the exact significance of the differences between Neandertal DNA and DNA from living people could not be fully understood. Perhaps any human DNA that old would be rather different from contemporary human DNA, owing to microevolutionary changes over time, they argued. One of the new studies appears to bear that suspicion out.
Reporting in the January 16 Proceedings of the National Academy of Sciences, Gregory J. Adcock of the Pierre and Marie Curie University in Paris and his colleagues extracted and analyzed mtDNA from Australian fossils representing anatomically modern humans. One of these, a specimen known as Lake Mungo 3 (LM3), dates to approximately 62,000 years old. As such, the LM3 mtDNA is the oldest known for a modern. It is also older than the two Neandertal samples analyzed last year and perhaps older than the sample that formed the basis of the Cell report (the age of the fossil that yielded that mtDNA is unknown).
Importantly, Adcock's team discovered that the LM3 mtDNA differed from that of living people as much as the Neandertal mtDNA did. In contrast, the mtDNA from the younger Australian fossils closely resembles that of living humans. "If the mitochondrial DNA sequences present in a modern human (LM3) can become extinct, then perhaps something similar happened to the mitochondrial DNA of Neandertals," noted John H. Relethford of the State University of New York at Oneonta in a commentary accompanying the PNAS report. If so, he says, the absence of Neandertal mtDNA in living humans does not rule out the possibility that they contributed to our gene pool. Other researchers are reserving judgment until the results are replicated in an independent lab, citing the possibility of contamination.
n truth, the mtDNA studies are additionally problematic because the history of a single gene does not necessarily reflect the history of a population. Different genes can tell different stories, and mtDNA, as far as human evolution researchers are concerned, represents only one gene. Unfortunately, with regard to ancient DNA, the chances of recovering nuclear DNA (and thus other genes) from early human fossils with currently available techniques are quite slim. Fossils thus remain very much a part of the human origins debate.
To that end, the second study published this month calling the Out of Africa replacement scenario into question focused on bones. According to their report in the January 12 Science, Milford H. Wolpoff of the University of Michigan and his colleagues set out to test the replacement theory by examining early modern human skulls from Central Europe and Australia dated to between 20,000 and 30,000 years old (above), searching for genetic input from more than one population. Both groups apparently exhibit traits seen in their Middle Eastern and African predecessors. But the early modern specimens from Central Europe also display Neandertal traits, and the early modern Australians showed affinities to archaic Homo from Indonesia. "These features amount to a smoking gun for continuity within these regions," says team member John Hawks of the University of Utah.
"Ancient humans shared genes and behaviors across wide regions of the world, and were not rendered extinct by one 'lucky group' that later evolved into us," Wolpoff asserts. "The fossils clearly show that more than one ancient group survived and thrived." Eventually, multiregionalists argue, Neandertals and other archaic humans as entities disappeared through interbreeding. (Other paleoanthropologists dispute the new data, noting that previous analyses of these same skulls have supported the replacement model.)
To be sure, the new findings will not end the decades-long debate over modern human origins. Where it will go from here, however, is anyone's guess.
December 2000 issue
Paleolithic Pit Stop
A French site suggests Neandertals and early modern humans behaved similarly
By Kate Wong
DORDOGNE, FRANCE--With thousands of caves and rockshelters peppering an area only slightly larger than New Jersey, southern France's Dordogne region is a mecca to archaeologists who study Stone Age ways of life. For more than 300,000 years humans have occupied this territory, and for 35 years University of Bordeaux archaeologist Jean-Philippe Rigaud has been unearthing the remnants of their past in hopes of determining how modern human behavior emerged.
As we drive past the cornfields and grazing horses and the stone farmhouses with their red tile roofs, Rigaud calls my attention to a hill in the distance, rising from the flat floor of the Dordogne River Valley like a giant green turtle. Grotte XVI, a site that he is currently excavating, is one of 23 caves that line a 1.5-kilometer-long cliff running along that hill, he explains. The locality has proved exceptionally rich. Over the past 17 years the field team has documented upward of 50,000 artifacts from at least 11 different archaeological levels dating back as far as 75,000 years ago, when Neandertals inhabited the cave. As such, Grotte XVI provides a rare opportunity for scientists to compare how Neandertals and early modern humans used the same living space--a comparison that is indicating that the two groups were more similar than previously thought.
The cave entrance faces west, gaping 10 meters wide and nine meters high. Inside, Rigaud's colleague, University of Tennessee archaeologist Jan F. Simek, supervises the French and American graduate students excavating the chamber, which extends 20 meters deep. Weighted cords hang from a metal frame above, forming a grid system of one-meter squares that, with the help of a surveying instrument, allows the workers to map the original position of every collected item in three dimensions. Each student controls a meter-square plot and is responsible for all of the related digging, mapping, sifting and washing, Simek explains. All of the collected materials--including animal remains and bits and pieces from tool manufacture--are then shipped to the University of Bordeaux for later examination.
Excitement erupts as team member Maureen Hays announces that she has just uncovered a Mousterian hand ax--a pear-shaped, multipurpose tool from the so-called Middle Paleolithic period, made in a style that in Europe is associated with Neandertals. Simek grins as Hays places the putty-colored rock in his palm for inspection. Not the finest example of Neandertal handiwork, he proclaims, but a hand ax nonetheless. According to team tradition, Hays will buy the champagne.
Comparisons between the Mousterian and the Aurignacian--an Upper Paleolithic cultural tradition associated with anatomically modern humans--at Grotte XVI have led Simek and Rigaud to an intriguing conclusion. Whereas a number of researchers have argued that the transition from the Middle Paleolithic to the Upper Paleolithic was rapid, corresponding to a replacement of Neandertals by moderns, the Grotte XVI assemblages fail to support that idea. The Upper Paleolithic does represent a shift toward specialized hunting, Simek observes, but the change is gradual.
Indeed, preliminary analysis suggests that the Neandertal and early modern human inhabitants of Grotte XVI behaved in much the same way: in both cases, small groups of hunters seem to have used the cave for only short periods before moving on, and both hunted the same kinds of animals. In fact, both groups appear to have fished extensively, judging from the abundant remains of trout and pike, among other species. This finding is particularly interesting because Neandertals are not generally assumed to have made use of aquatic resources. Furthermore, Simek reports, Neandertals may have even smoked their catch, based on evidence of lichen and grass in the Mousterian fireplaces. Such plants don't burn particularly well, Simek says, but they do produce a lot of smoke. "People don't tend to think of Neandertals as using fire in very complex ways," he remarks, "and they did." (The fireplaces, which date to between 54,000 and 66,000 years ago, are themselves noteworthy as the best-preserved early hearths known, according to Simek. Striking bands of black, red, pink, orange, yellow and white reveal carbon and various stages of chemically decomposed ash that indicate short, hot fires.)
Although a radical shift did not occur between the Middle and Upper Paleolithic, Simek notes that significant change did come later with the so-called Magdalenian period, perhaps because population size was increasing. Remains from sediments toward the back of the cave reveal that around 12,500 years ago the Magdalenians used Grotte XVI specifically as a hunting site, leaving behind characteristic harpoons and other implements. The team has also unearthed engraved art objects in the Magdalenian deposits. That they brought artwork with them into mundane activities, Simek says, is important. "Like we might carry a cross, they carried their religious iconography, too."
Lunchtime approaches, and the crew prepares to head up to Rigaud's house. As the cave empties out, I comment that working here seems like a wonderful way to spend the summer. Yes, Simek agrees, leaning on the scaffolding and surveying the site contentedly, "It's a great privilege to do this."
January 1999 issue
OUT OF AFRICA, INTO ASIA
Controversial DNA studies link Asian hunter-gatherers to African pygmies
By Madhusree Mukerjee
Scientists may have pinpointed direct descendants of the first humans to migrate out of Africa into Asia. They could be the aboriginal inhabitants of the Andaman Islands in the Bay of Bengal, who have long been noted for their resemblance to African pygmies. Some convergence of features--dark skin and small, gracile form--is to be expected in peoples who have evolved in the tropics. But a recent DNA study of hair from Andamanese individuals, collected in 1907 by British anthropologist Alfred R. Radcliffe-Brown, suggests a closer connection.
Carlos Lalueza Fox, a postdoctoral fellow at the genetics laboratory of Erika Hagelberg at the University of Cambridge, had extracted DNA from 42 out of 70 hair samples and amplified a short segment of DNA from the mitochondria. Known as mtDNA, such DNA is less directly related to physical characteristics than chromosomal DNA and is therefore believed to be less sensitive to the pressures of natural selection. Fox and Hagelberg found that the sequences of base pairs in the mtDNA fragments clustered closer to African populations--especially southern African pygmies--than to Asian ones.
If substantiated, the findings will lend support to the Out of Africa theory of human descent. Proponents hold that the first humans left Africa some 100,000 years ago, reaching Asia around 60,000 years ago. According to Peter Bellwood of Australian National University in Canberra, some of these hunter-gatherers moved southward to New Guinea and Australia during the ice ages 40,000 years ago. At the time, glaciers had sucked water out of the oceans, lowering the sea level and expanding Asia into a vast region known as Sundaland. As a result, much of the southward migration occurred on foot.
Archaeological evidence of human occupation of the Andamans, excavated most recently by Zarine Cooper of Deccan College in India, dates back at most 2,200 years. But Bellwood guesses that the Andamanese reached their islands during the first wave of human migration at least 35,000 years ago. Eventually the seas rose, cutting them off. The seas were to fall and rise many more times, most recently about 10,000 years ago. Andamanese mythology describes violent storms and deluges that drowned the islands, forcing the survivors to repair to the former hilltops.
Almost all the first humans in Asia were wiped out by waves of later migrants; survivors persisted only in isolated, embattled pockets. The Andamanese ensured their own survival--at least until modern times--by determined opposition to all seafarers who attempted to land. To this day, one group of Andamanese, inhabiting tiny North Sentinel Island, attacks with arrows any approaching boats.
The Out of Africa theory has also received recent support from an extensive survey of Chinese DNA conducted by Li Jin of the University of Texas at Houston and his colleagues. The researchers examined DNA markers called microsatellites from 28 ethnic groups across China, including four from Taiwan. They found only minor genetic variations among the populations, suggesting that these groups had had little time to diverge from one another. Possibly, they all arose from recent African migrants.
A rival scenario derives from the Multiregional hypothesis, which holds that humans evolved separately in different parts of the world from populations of Homo erectus that dispersed (also from Africa) one to two million years ago. These groups of humanoids managed to develop into a single species--H. sapiens--by exchanging genes with one another. To some anthropologists, fossils excavated in China suggest a continuum between H. erectus and modern Chinese peoples. Milford Wolpoff of the University of Michigan has pointed out that interbreeding could have ensured that the descendants of different humanoids ended up being genetically similar.
Wolpoff is likewise skeptical of the Andaman study, which cannot be properly critiqued until it is published. An unfortunate dispute regarding the hair has held up publication. Robert A. Foley, director of the Duckworth Collection at Cambridge, which owns the hair, has complained that permission was never obtained for its use. Hagelberg protests that Foley knew about the study for at least a year before voicing this objection when the results were reported at a conference in August. Matters became so unpleasant that Hagelberg has packed up her lab and moved to the University of Otago in Dunedin, New Zealand.
The research will be difficult to replicate, because fresh materials from the Andamanese are scarce. Access to blood, hair and other human samples is restricted by many countries (in this case, India) for fear that the genetic information they contain will be misused--specifically, put to commercial use. So it will be a while before the intriguing links between Andamanese and Africans strengthen into familial bonds.
August 1999 issue
IS OUT OF AFRICA GOING OUT THE DOOR?
Reanalysis of gene studies and new fossil evidence cast doubts of a popular theory of human origins
By Kate Wong
Anthropologists have long debated the origins of modern humanity, and by the mid-1980s two main competing theories emerged. One, Multiregional evolution, posits that humans arose in Africa some two million years ago, evolved as a single species spread across the Old World and were linked through interbreeding and cultural exchange. The Out of Africa hypothesis, in contrast, proposes a much more recent African origin for modern humans--a new species, distinct from Neanderthals and other archaic humans, whom they then replaced. Emphatic support for Out of Africa came in 1987, when molecular biologists declared that all living peoples could trace a piece of their genetic legacy back to a woman dubbed "Eve," who lived in Africa 200,000 years ago. Although that original Eve study was later shown to contain fatal flaws, Out of Africa has continued to enjoy much molecular affirmation, as researchers have increasingly turned to DNA to decipher the history of our species.
But a closer look at these genetic studies has led some researchers to question whether the molecular data really do bolster the Out of Africa model. And striking new fossil data from Portugal and Australia appear to fit much more neatly with the theory of Multiregional evolution.
The DNA from mitochondria, the cell's energy-producing organelles, has been key Out of Africa evidence. Mitochondria are maternally inherited, so genetic variation arises largely from mutation alone. And because mutations have generally been thought to occur randomly and to accumulate at a constant rate, the date for the common mitochondrial DNA (mtDNA) ancestor can theoretically be calculated. This "molecular clock" indicates that the mtDNA ancestor lived a a mere 200,000 years ago, and the root of the gene tree traces to Africa. These results, along with the observation that variation is highest in Africa (indicating that modern humans had been in Africa the longest), seemed to offer unambiguous support to a recent African origin for all modern humans.
But the significance of each finding has been questioned. The date is suspect because the molecular clock depends on problematic assumptions, such as the calibration date and mutation rate. And if natural selection has shaped mtDNA, as some studies suggest, then the rate of mutation accumulation may have differed at different times. The African root for the mtDNA gene tree is compatible with Out of Africa, but it does not exclude Multiregionalism, which predicts that the common ancestor lived somewhere in the Old World, probably Africa. And neither does the high mtDNA variation in African populations as compared with non-Africans uniquely support Out of Africa, according to anthropologist John H. Relethford of the State University of New York College at Oneonta. "You could get the same result if Africa just had more people living there, which makes sense ecologically," he asserts.
Another problem plaguing the genetic analyses, says geneticist Alan R. Templeton of Washington University, lies in a tendency for researchers to draw conclusions based on the particular genetic system under study. "Very few people try to look across all the systems to see the pattern," he observes. Some nuclear genes indicate that archaic Asian populations contributed to the modern human gene pool, and Templeton's own analyses of multiple genetic systems reveal the genetic exchange between populations predicted by Multiregionalis
Still, Relethford and Templeton's arguments haven't convinced everyone. Henry C. Harpending, a population geneticist at the University of Utah, finds Multiregionalism difficult to swallow because several studies put the prehistoric effective population size--that is, the number of breeding adults--at around 10,000. "There's no way you can get a species going from Peking to Cape Town that's only got 10,000 members," he remarks. (Other researchers counter that this number, based on genetic diversity, may be much smaller than the census size of the population--perhaps by several orders of magnitude.) And many geneticists, such as Kenneth K. Kidd of Yale University, insist that "the overwhelming majority of the data is incompatible with any ancient continuity."
But those who believe that Out of Africa's genetic fortress is crumbling find confirmation in fresh fossil data that pose new difficulties for the theory's bony underpinnings. Last December researchers unearthed in western Portugal's Lapedo Valley a fossil that preserves in exquisite detail the skeleton of a four-year-old child buried some 24,000 years ago. According to Erik Trinkaus, a Washington University paleoanthropologist who examined the specimen, the team fully expected the remains to represent a modern human, based on its date and the style of the burial. But subsequent analysis, published in the June 22 Proceedings of the National Academy of Sciences USA, revealed a surprising combination of features, such as a modern-looking chin and Neanderthal limb proportions. After reviewing scientific literature on primate hybrids, Trinkaus concluded that this child resulted from interbreeding between Neanderthals and modern humans.
Not everyone is persuaded. Christopher B. Stringer of London's Natural History Museum, lead proponent of the Out of Africa model, wonders whether the fossil might simply represent a cold-adapted modern human, because Portugal then was colder than it is today. In any case, Stringer maintains that his model does not exclude occasional interbreeding.
Yet Trinkaus notes that because the fossil is dated to thousands of years after these groups came into contact, "we're looking at populations admixing." Furthermore, adult fossils from central and eastern Europe show the effects of mixing, too, states paleoanthropologist David W. Frayer of the University of Kansas. And if the groups were interbreeding across Europe, asserts University of Michigan multiregionalist Milford H. Wolpoff, "that would mean you could make a strong case that [contemporary] Europeans are the result of the mixture of these different groups." Another name for that, he says, is Multiregional evolution.
Multiregionalism also best explains the surprising new date for a previously known fossil from western New South Wales, according to paleoanthropologist Alan Thorne of the Australian National University. In the June Journal of Human Evolution Thorne and his colleagues report that the fossil, known as Lake Mungo 3, now looks to be some 60,000 years old--nearly twice as old as previously thought--and unlike the other early Australian remains (all of which date to less than 20,000 years ago), this one bears delicate, modern features. To Stringer, this gracile form indicates the arrival of modern humans from Africa, albeit an early one. Over time, he reasons, selection could have led to the robust morphology seen 40,000 years late
But Thorne argues that such dramatic change is unlikely over such a short period and that fossils from the only environmentally comparable region--southern Africa--show that people have remained gracile over the past 100,000 years. Moreover, Thorne maintains, "there is nothing in the evidence from Australia which says Africa"--not even the Mungo fossil's modern features, which he believes look much more like those of contemporaneous Chinese fossils. And Thorne observes that living indigenous Australians share a special suite of skeletal and dental features with humans who inhabited Indonesia at least 100,000 years ago.
Therefore, he offers, a simpler explanation is that the two populations arrived in Australia at different times--one from China and the other from Indonesia--and mixed, much like what has been proposed for Neanderthals and moderns in Europe. Exactly the same pattern exists in recent history, Thorne adds, pointing to the interbreeding that took place when Europeans arriving in North America and Australia encountered indigenous peoples. "That's what humans do." The mystery of human origins is far from solved, but because DNA may not be as diagnostic as it once seemed, Thorne says, "we're back to the bones." University of Oxford geneticist Rosalind M. Harding agrees. "It's really good that there are things coming from the fossil side that are making people worry about other possibilities," she muses. "It's their time at the moment, and the DNA studies can just take the back seat."
December 07, 2000
Rooting the Human Family Tree in Africa
Scholars have long debated the exact origins of our species. Some have maintained that modern humans probably arose simultaneously in several regions of the globe. They base these arguments largely on the fossil record, which shows that some of our immediate predecessors—Homo neanderthalensis and Homo erectus, for instance—had migrated out of Africa as early as two million years ago. But a new study published in today's issue of Nature lends more credibility to the rival theory—namely that Homo sapiens emerged only in Africa, and only later infiltrated other regions, wiping out the Neanderthals already living there over time.
Instead of tracking our family tree with fossils, the study's authors—Ulf Gyllensten and Max Ingman of the University of Uppsala, and Henrik Kaessmann and Svante Pддbo of the Max Plank Institute for Evolutionary Anthropology—turned to the living. They completed the most extensive analysis of mitochondrial DNA (mtDNA) ever done, taking samples from 53 people having diverse geographical, racial and linguistic backgrounds. Unlike the DNA within chromosomes, which is inherited from both parents and so changes slightly with each generation, mtDNA is passed directly from mother to child; only random mutations alter its sequence. As a result, it offers a powerful measure of how closely different populations are related.
Earlier work on mtDNA had focused exclusively on the control regions of the sequence, which account for a scant 7 percent of its total. In contrast, Gyllensten and his colleagues worked out the entire mtDNA sequence—a string of some 16,500 base pairs—for each individual in their study. From this data, they weeded out stretches of DNA that had mutated unusually quickly and so very likely represented little more than twigs on the family tree. When they compared the rest, a trunk and major branches became clear: the most recent common ancestor of all subjects in the study lived in sub-Saharan Africa some 171,500 to 50,000 years ago, suggesting that we are all descended from a single group there. In addition, they found a major branch separating most Africans from non-Africans, which probably represents H. sapiens' first major exodus from the continent, 52,000 to 27,500 years ago. --Kristin Leutwyler
August 2000 issue
New fossils revise the time when humans colonized the earth
By Kate Wong
Scientists have long known that hominids arose in Africa and that for the first few million years they stayed there. But at some point our ancestors began to move out of their motherland, marking the start of global colonization. Determining why and when they left, however, has proved difficult because of the scarcity of early human fossils. Now two ancient skulls from the Republic of Georgia provide the strongest evidence yet of the first humans to journey out of Africa. According to a report in the May 12 Science, they appear to have accomplished this far earlier-and with a much more modest technology-than many investigators had expected.
Researchers unearthed the skulls in Dmanisi, about 85 kilometers southwest of the Georgian capital, Tbilisi. Based on radiometric dating of the volcanic layer underlying the fossils, paleomagnetic measurements and the presence of animal species whose age has been documented elsewhere, the team dated the skulls to around 1.7 million years ago-at least 300,000 years older than stone tools from a site in Israel called ‘Ubeidiya that were considered the oldest undisputed traces of humans outside Africa.
The finding-coupled with previously known fossils from Dmanisi whose antiquity was originally doubted-overturns a popular theory aimed at explaining what prompted the first colonizers to venture out of Africa. The stone tools from ‘Ubeidiya represent an advanced industry known as Acheulean, which includes carefully crafted hand axes and other double-edged tools well suited to carving meat. The earliest Acheulean tools come from Africa and date to about 1.6 million years ago. Prior to that, hominids were using a more primitive technology dubbed Oldowan. Researchers thus proposed that the development of the Acheulean enabled early humans to finally leave Africa, because the tools gave them a better means of scavenging and hunting. Dmanisi, however, has yielded Oldowan, not Acheulean, tools.
Taking that into consideration, a more viable explanation for the dispersal stems from anatomical shifts rather than new technology, according to team member David Lordkipanidze of the Georgia State Museum. The Dmanisi hominids most closely resemble an early member of our genus that some researchers call Homo ergaster (others prefer the designation early African H. erectus, and still others call it early H. sapiens). With the emergence of this form around two million years ago, says University of Michigan paleoanthropologist Milford H. Wolpoff, "we get someone who is three times the weight and twice the height of all australopithecines, with really long legs." The only way to maintain this body size, he notes, is through a higher-quality diet than that of the australopithecines. Higher quality, in this case, probably meant including meat. With long legs, Homo was well equipped to patrol the larger home range that carnivory requires. After adopting this hunter-gatherer subsistence strategy, it was only a matter of time before these ancient humans expanded into Eurasia.
Indeed, researchers will most likely uncover Eurasian remains even older than Dmanisi, surmises Susan C. Antуn, a paleoanthropologist at the University of Florida and member of the Dmanisi research team. Remains from Java hint at human occupation as early as 1.8 million years ago, and getting there would have required moving through Eurasia. Although many scholars regard the date assigned to these fossils with a great deal of skepticism, early Homo certainly could have reached Southeast Asia within that time frame, according to Harvard University archaeologist Ofer Bar-Yosef. In fact, he estimates that such a dispersal would have taken hunter-gatherers only a few thousand years. (Importantly, as with Dmanisi, the only tools known from the earliest East Asian sites are of the Oldowan variety.
Early dates for Java aside, humans had reached eastern China by 1.1 million years ago. Yet the earliest accepted Europeans are 780,000-year-old fossils from Spain. Why they appear to have taken so long to reach western Europe, which is closer to the exit route from Africa than is East Asia, remains unclear. One theory posits that large-jawed carnivores, which left little for scavengers, prevented humans from establishing a foothold there. Others imagine that inhospitable climate and geography thwarted early European colonization. But Bar-Yosef suspects that older European sites will turn up, demonstrating that some of the emigrating groups headed from Africa into Mediterranean Europe. A more conservative view comes from Antуn, who doubts that any older fossils will come from that region. Then again, she remarks, "Dmanisi really shows us how little we know about the potential sites that are out there."
November 2000 issue
The Caveman’s New Clothes
From what they wore to how they hunted: overturning the threadbare reconstructions of Ice Age culture
By Kate Wong
PARIS--Walking through the human evolution exhibit in the Musйe de l'Homme, two things stand out to Olga Soffer: males are depicted to the exclusion of females, and they're wearing the wrong clothes. Only someone who has never sewn before would conclude that this needle could have pierced through hides, she declares, drawing my attention to a delicate sliver of bone in one of the display cases. Rather, the University of Illinois archaeologist asserts, it must have stitched a far finer material--perhaps even something akin to the linen of her blue pinstriped suit.
OLGA SOFFER: FASHION MAVEN TURNED ARCHAEOLOGIST
Such needles--some of which date back more than 25,000 years to the Upper Paleolithic period--vaguely suggest that caveman couture extended beyond the crude animal-skin ensembles envisioned by many of her colleagues. Soffer's efforts are revealing just how sophisticated those first fashionistas were. By scouring the archaeological record for evidence of perishable technologies like weaving, she has uncovered clues to formerly invisible activities of Ice Age men--and women--forcing a reevaluation of the men-in-furs-hunting-megafauna motif that has long dominated reconstructions of prehistoric lifeways. The fabric of their lives, it appears, was much richer than previously thought.
Soffer's passion for fashion predates her interest in the Paleolithic. After graduating from Hunter College with a degree in political science, she entered an executive training program with New York City's Federated Department Stores--owners today of Macy's, Bloomingdale's and others. This led to a 10-year career in fashion promotion, which, she says, suited her just fine early on but grew tiresome as she reached her late 20s. "I started playing hooky," she recalls, chuckling. "I'd go to fashion shows and actually sneak off to the library."
To feed her mind, Soffer decided to take some night school courses in art. In a couple of years she worked her way from Picasso to prehistoric art to prehistoric ways of life and concluded that she "might as well" get her master's in archaeology. Then, after taking a summer off from her job to go to France "to learn digging," Soffer decided to pursue a Ph.D. through the City University of New York while continuing to work halftime in fashion during the first two years.
In 1977 she left for Russia, accompanied by her then husband and her six-year-old daughter, to conduct her dissertation research. Russia was an open niche, she recollects, unlike France, where, she says, there was "a ratio of about two archies for one square meter of territory." Additionally, her Russian parentage meant that she had the advantage of language and cultural sensitivity. There on the central Russian Plain, home of the famous Upper Paleolithic mammoth-bone dwellings, she developed her interest in prehistoric subsistence practices. There, too, she began to wonder whether conventional wisdom on the matter was flawed.
"We bring an awful lot of baggage to prehistory," Soffer rues. Take, for example, that perennially popular Ice Age scene, the mammoth hunt. She doesn't buy it. No known living or recent hunter-gatherer groups have ever survived on elephants, she observes. Like elephants, mammoths were dangerous animals, and the close encounters required by handheld spear hunting would have posed far too many risks. What then of those mammoth-bone assemblages in Russia and elsewhere in eastern and central Europe? The same sites have also yielded the remains of numerous small animals, such as rabbits and marmots. "If they've got all this mammoth meat, why in heaven's name are they hunting bunnies?" she demands. A more plausible explanation for most of the mammoth bones is that people collected them off the landscape from animals that died of other causes. She concludes that mammoth and other megafauna hunts were occasional and did not play a central dietary role.
As for bringing down those small animals, Soffer suspects it wasn't with spears. She and James M. Adovasio of Mercyhurst College have identified impressions of netting on fragments of clay from Upper Paleolithic sites in Moravia and Russia that open up an intriguing possibility: net hunting. Ethnographic descriptions of this strategy, Soffer explains, reveal that "you don't need to be a strong, brawny, skilled hunter. You can participate and help with this kind of communal hunt if you're a kid with no experience, if you're a nursing mother, et cetera. It's nonconfrontational" and relatively safe. Impressions of netting and other perishable materials provide some of the first insight into the lives of prehistoric women, children and the elderly--or, as Soffer describes them, the silent majority. Whereas the activities of prime-age males in hunter-gatherer cultures tend to entail the manipulation of durable materials, those of women, children and the elderly involve more perishables. As a result, the archaeological record has preferentially preserved behavioral remains associated with young men.
Soffer's efforts, however, have demonstrated that it is quite possible to recover evidence of what these other people did. Over the past few years she and her colleagues have identified all sorts of plant fiber artifacts--impressions of cordage, textiles, basketry--from Upper Paleolithic sites across Europe. And research conducted just last year indicates that certain bone and antler objects once thought to be hunting tools actually represent tools used to manufacture these perishable items: net gauges and battens for weaving, for instance.
Although remains of perishables are known from 13,000-year-old Paleoindian sites [see "Who Were the First Americans?" by Sasha Nemecek; Scientific American, September], these Upper Paleolithic materials push back the date for the oldest plant-based technologies by thousands of years. But they're still too advanced to represent the origins of such practices. Indeed, the most basic of these technologies--cordage--probably dates back at least 60,000 years to the first colonizers of Australia, whom many researchers suspect sailed over from Southeast Asia. Considering the limited availability of animal sinew in that region, Soffer says, their rafts would most likely have been lashed together with ropes made of plant fibers.
Most of Soffer's startling observations have been made on archaeological materials that were discovered long ago. Yet until now, no one had noticed them. That's because they weren't looking for it, she asserts. "If you're looking with these questions in mind, stuff that had always been there starts jumping out at you--like the fact that the Venus figurines are dressed. They're wearing clothes, for God's sake." Although these voluptuous female statuettes from Upper Paleolithic sites across Europe have been known for decades, most scholars overlooked their apparel. How? "Because an awful lot of people who were studying this stuff were men who looked at the variables that were far more emotionally charged: secondary sex characteristics," Soffer remarks matter-of-factly. "When we started looking at these things as archaeologists, looking at the range of variables and the patterning of those variables--aside from boobs and asses--lo and behold, there's this other stuff."
The other stuff, it appears, includes a stunning array of ritual garb: the famed Venus of Willendorf from Austria wears a woven hat (previously interpreted as a coiled coiffure); the French Venus of Lespugue sports a string skirt; other Venuses model bandeaus, snoods, sashes and belts. Close study of the carvings reveal that all the representations of apparel clearly depict fiber-based items, as opposed to hidewear, further strengthening the case for early textiles.
These Paleolithic representations of women stand in stark contrast to the few known representations of men, none of which show clothing. Whether these mysterious figurines represent sex symbols, fertility goddesses or some other entities, we may never know. Yet to Soffer, the fact that ancient artists took such pains to immortalize their apparel clearly illustrates the importance of these perishable technologies. And if the ethnographic record on perishables is any indication, the manufacturers were probably women. "Women were not just out there to reproduce," Soffer insists. "They were actively involved in production as well, just as women are in any and all societies that we know of."
July 2003 issue
Drenched in Symbolism
A dazzling record of prehistoric carvings and paintings testifies to the cognitive complexity of our species
By Ian Tattersall
About 40,000 years ago the first Homo sapiens--the Cro-Magnons--began to trickle into Europe, displacing the resident Neanderthals in the process. The contrast between the records of their lives that these very different hominids left behind could hardly be more striking. For no extinct human species, not even the large-brained Homo neanderthalensis, has bequeathed us evidence of a complex symbolic existence, based on the extraordinary cognitive capacities that distinguish us from all other living species today. In contrast, the lives of the Cro-Magnons were drenched in symbolism.
Well over 30,000 years ago these early people were creating astonishing art on the walls of caves. They crafted subtle and beautiful carvings and engravings and kept records by incising intricate notations on bone plaques. They made music on bone flutes, and if they did this, they surely sang and danced as well. They ornamented their bodies and buried their dead with elaborate grave goods, presumably to serve them in an afterlife. Technologically, a cascade of innovations included nets, textiles and ropes, even the first ceramics. In short, those Cro-Magnons were us: members of a species whose relationship with the rest of the world was totally unprecedented in the entire history of life.
For a couple of decades now, New York University archaeologist Randy White has been a leading investigator of how the expression of the unique human capacity unfolded in Europe during the two dozen millennia that followed the arrival of the Cro-Magnons. In this thoughtful and very beautiful book, White concentrates on the most dazzling part of this record, the part that embraces what we would call art--and that includes some of the most powerful ever made. But he is careful to point out that "art" is very much a Western concept and that for its creators, what looks to us like art probably had implications vastly different from those we impute in our own society to art and decoration. For while nobody could doubt that Cro-Magnon symbolic production somehow reflected these people's conceptions of their place in the natural world, the Cro-Magnons were hunters and gatherers, with a perceived relationship to nature that must have been radically different from our own.
For this reason, White eschews the elaborate explanations that so many authors feel somehow obliged to bring to the interpretation of prehistoric art and hews to the facts. He begins with a brief history of the discovery and interpretation of Cro-Magnon art, as prelude to a largely chronological account of the evidence for symbolic expression in Europe and parts of northern Asia between about 40,000 and 10,000 years ago. In these sections, White mostly avoids stylistic analysis in favor of a focus on techniques, but he manages to address, if usually briefly, most of the major questions that Cro-Magnon art elicits.
As perhaps befits a work that grew out of a university survey course, this volume extends beyond mainly European Ice Age art to consider prehistoric symbolic and representational traditions (some earlier, others quite recent) in Africa, southern and western Asia, Australia, and the Americas. Each of these regional groupings is treated separately, and White wisely refrains from drawing close parallels between different regional traditions. Of course, including all these diverse traditions between the covers of a single book might be taken to imply a unity that contradicts White's insistence on the unique cultural roots and referents of each one of them. But the fact that all are the products of hunting-gathering peoples serves very usefully to remind us of the vast range of iconographies and aesthetics available even to noncomplex human societies.
What White's spectacularly illustrated book does most clearly, then, is to bring home the astonishing diversity and intricacy of the representational traditions that the extraordinary human symbolic spirit has from the beginning produced worldwide, even in the absence of complex social and economic structures. The remarkable human cognitive capacity that early art reflects appeared quite recently, perhaps less than 100,000 years ago. And that appearance set our species on a course of accelerating technological change and elaboration that may yet run out of our control. But White shows that although our economic lives have changed out of recognition in that time, the potential that underwrites our modern lifestyles and achievements was there from the very start. Deep down, human beings haven't changed one whit since prehistoric times.
Ian Tattersall is a curator of physical anthropology at the American Museum of Natural History in New York City. His most recent book is The Monkey in the Mirror (Harcourt, 2002).
December 06, 2001
Fossil Teeth Reveal How Modern Humans' Growth Patterns Differ from Other Primates'
It's often said that teenagers today just can't wait to grow up. But humans' long period of growth and development—18 years or more—is one of the things that sets us apart from great apes such as chimpanzees and gorillas, which mature in only 11 or 12 years. Now new research, published in this week's issue of Nature, suggests that our long period of development arose quite late in our evolutionary history.
Christopher Dean of University College, London and colleagues examined 13 fossil tooth fragments from specimens dating between four million and 120, 000 years ago. "Dental development is a good measure of overall growth and development," co-author Alan Walker of Pennsylvania State University explains. "Teeth grow in an incremental manner like trees or shells, preserving a record of their growth with daily marks along the prisms that make up the enamel." By examining patterns (see image) within the enamel of both the fossil and modern teeth, the scientists calculated and compared rates of growth.
The first dental evidence for a modern human-like growth period, the scientists discovered, was in a Neanderthal fossil from around 120,000 years ago. What's more, the researchers found that Homo erectus, despite its complement of many modern human characteristics such as body proportions, weight and small teeth and jaws, did not exhibit a slow growth period. They suggest this finding may be linked to the fact that, compared to modern humans, Homo erectus still had a small brain, which would not require as much time to grow and learn. "It seems our prolonged period of growth and development may be a more recent evolutionary acquisition that arose in step with our comparatively recent development of a larger, modern, human-sized brain," Walker says.
In an accompanying commentary in the same issue, Jocopo Moggi-Cecchi of the University of Florence writes, "it is becoming increasingly clear that many features thought to be typical of modern humans may have evolved more than once." The present study he adds, "raises new challenges in the search for fossil evidence of those characteristics that define both our genus and our species." --Sarah Graham
June 12, 2003
Skulls of Oldest Homo sapiens Recovered
Scientists have unearthed in Ethiopia three 160,000-year-old skulls that they say are the oldest near-modern humans on record. Telltale marks on the bones suggest that the hominids engaged in mortuary rituals. The fossils are described in two reports published today in the journal Nature.
A team led by Tim White of the University of California at Berkeley, Giday WoldeGabriel of Los Alamos National Laboratory and Berhane Asfaw of the Rift Valley Research Service in Ethiopia recovered the fossils near a village known as Herto in Ethiopia's Middle Awash region. The researchers found them, together with bone fragments and teeth from seven other individuals, among hippopotamus bones and a variety of blades and other tools. The three skulls--belonging to two adults and a six- to seven-year-old child--share a number of traits in the face and braincase with modern humans. But slight differences in the morphology convinced the scientists to assign the fossils to a subspecies, Homo sapiens idaltu. Paleoanthropologist Chris Stringer of the Natural History Museum in London writes in an accompanying commentary, however, that "despite the presence of some primitive features, there seems to be enough morphological evidence to regard the Herto material as the oldest definite record of what we currently think of as modern H. sapiens."
The new finds lend support to the so-called Out of Africa hypothesis, which holds that H. sapiens arose as a new species between 150,000 and 200,000 years ago in Africa and subsequently replaced archaic humans such as the Neanderthals. "These fossils show that near-humans had evolved in Africa long before the European Neanderthals disappeared," says team member Clark Howell of Berkeley. "They thereby demonstrate conclusively that there was never a 'neanderthal' stage in human evolution." But whether early modern human morphology originated solely in East Africa or emerged in a number of populations around the continent remains unknown. Stringer notes that future fossil finds, as well as improved dating of previously discovered remains, should help further unravel the mystery. --Sarah Graham
May 14, 2003
The story of where modern humans came from has never been cut-and-dried, but two theories occupy the forefront of the debate. According to the Out of Africa model, Homo sapiens arose as a new species approximately 150,000 to 200,000 years ago in Africa and went on to replace archaic humans such as the Neandertals. The multiregional evolution model, in contrast, holds that archaic populations, the Neandertals among them, contributed to the modern human gene pool. New findings published online this week by the Proceedings of the National Academy of Sciences lend support to the former model, suggesting that moderns replaced Neandertals without interbreeding.
David Caramelli of the University of Florence and his colleagues extracted and analyzed mitrochondrial DNA (mtDNA) from the skeletons of two early modern Europeans (sometimes referred to as Cro-Magnons) collected from Paglicci Cave in southern Italy. The remains of the teenaged boy and young woman date to 23,000 and 25,000 years ago. The scientists compared the mtDNA from the two individuals to mtDNA from contemporary Europeans as well as to published mtDNA results from three Neandertal individuals between 29,000 and 42,000 years old. (The image above shows a cast of a skull of an early modern European on the left and one of a Neandertal specimen on the right.) They found that the Paglicci samples fit well within the genetic variation exhibited by today's Europeans, but differed significantly from the Neandertal specimens. "This discontinuity," the team writes, "is difficult to reconcile with the hypothesis that both Neandertals and early anatomically modern humans contributed to the current European gene pool." --Sarah Graham
February 2001 issue
Did humans hunt giant mammals to extinction? Or give them lethal disease?
By Kate Wong
MEXICO CITY--Although it's hard to imagine in this age of urban sprawl and automobiles, North America once belonged to mammoths, camels, ground sloths as large as cows, bear-size beavers and other formidable beasts. Some 11,000 years ago, however, these large-bodied mammals and others--about 70 species in all--disappeared. Their demise coincided roughly with the arrival of humans in the New World and dramatic climatic change--factors that have inspired several theories about the die-off. Yet despite decades of scientific investigation, the exact cause remains a mystery. Now new findings offer support to one of these controversial hypotheses: that human hunting drove this megafaunal menagerie to extinction.
The overkill model emerged in the 1960s, when it was put forth by Paul S. Martin of the University of Arizona. Since then, critics have charged that no evidence exists to support the idea that the first Americans hunted to the extent necessary to cause these extinctions. But at the annual meeting of the Society of Vertebrate Paleontology in Mexico City last October, paleoecologist John Alroy of the University of California at Santa Barbara argued that, in fact, hunting-driven extinction is not only plausible, it was unavoidable. He has determined, using a computer simulation, that even a very modest amount of hunting would have wiped these animals out.
Assuming an initial human population of 100 people that grew no more than 2 percent annually, Alroy determined that if each band of, say, 50 people killed 15 to 20 large mammals a year, humans could have eliminated the animal populations within 1,000 years. Large mammals in particular would have been vulnerable to the pressure because they have longer gestation periods than smaller mammals and their young require extended care.
Not everyone agrees with Alroy's assessment. For one, the results depend in part on population-size estimates for the extinct animals--figures that are not necessarily reliable. But a more specific criticism comes from mammalogist Ross D. E. MacPhee of the American Museum of Natural History in New York City, who points out that the relevant archaeological record contains barely a dozen examples of stone points embedded in mammoth bones (and none, it should be noted, are known from other megafaunal remains)--hardly what one might expect if hunting drove these animals to extinction. Furthermore, some of these species had huge ranges--the giant Jefferson's ground sloth, for example, lived as far north as the Yukon and as far south as Mexico--which would have made slaughtering them in numbers sufficient to cause their extinction rather implausible, he says.
MacPhee agrees that humans most likely brought about these extinctions (as well as others around the world that coincided with human arrival), but not directly. Rather he suggests that people may have introduced hyperlethal disease, perhaps through their dogs or hitchhiking vermin, which then spread wildly among the immunologically naive species of the New World. As in the overkill model, populations of large mammals would have a harder time recovering. Repeated outbreaks of a hyperdisease could thus quickly drive them to the point of no return. So far MacPhee does not have empirical evidence for the hyperdisease hypothesis, and it won't be easy to come by: hyperlethal disease would kill far too quickly to leave its signature on the bones themselves. But he hopes that analyses of tissue and DNA from the last mammoths to perish will eventually reveal murderous microbes.
The third explanation for what brought on this North American extinction does not involve human beings. Instead its proponents blame the loss on the weather. The Pleistocene epoch witnessed considerable climatic instability, explains paleontologist Russell W. Graham of the Denver Museum of Nature and Science. As a result, certain habitats disappeared, and species that had once formed communities split apart. For some animals, this change brought opportunity. For much of the megafauna, however, the increasingly homogeneous environment left them with shrinking geographical ranges--a death sentence for large animals, which need large ranges. Although these creatures managed to maintain viable populations through most of the Pleistocene, the final major fluctuation--the so-called Younger Dryas event--pushed them over the edge, Graham says.
For his part, Alroy is convinced that human hunters demolished the titans of the Ice Age. The overkill model explains everything the disease and climate scenarios explain, he asserts, and makes accurate predictions about which species would eventually go extinct. "Personally, I'm a vegetarian," he remarks, "and I find all of this kind of gross--but believable."
H. neanderthalensis differed from us in many respects. Morphologically speaking they tended to be shorter and more robust, and thought their brains were larger than ours, their neo-cortical ratio was still smaller. This page is particularly devoted to aspects of Neanderthal Morphology and various theories that purport to explain it.
The purpose of this brief paper will be to highlight the differences (as compared to H. sapiens) in the post-cranial skeletal structure of Neanderthal and then to attempt to understand why and for what reasons these characteristics manifested themselves. For sake of brevity, we will leave out the contentious issue, though in our opinion an all but answered one, of whether Neanderthal evolved into modern human beings or not (Brace 1964; Wolpoff 1980, 1989; Stringer and Gamble 1993, Shreeve 1995; Tattersall 1995).
Tibeal tuberosities and femoral muscle attachment areas are similarly very large. This, coupled with large, heavily catilaged knee joints with very thick patellae would give Neanderthal the capability to generate a massive amount of force around the knee area (Trinkaus 1983; Trinkaus and Thompson 1987; Stringer and Gamble 1993). Obviously Neanderthal was traversing rough terrain, jumping and breaking falls.
Furthermore, in cross-sectional analysis of Neanderthal tibiae and femora, we can see that not only are they larger in circumference, but more importantly, they show a considerable thickening of the internal walls (Trinkaus 1983, 1991). Furthermore, while later humans exhibit a tear drop shaped cross section in their femurs, Neanderthal femurs are round in cross section which tells us a great deal about their movements (Trinkaus 1983, 1985; Shreeve 1995). That is, they had to be more sedentary, while those that came after them, were much more likely to have travelled long distances regularly. Neanderthal obviously moved to and fro over rugged landscape, whereas moderns moved longer distances over easeir terrain as evidenced by the tear drop shape of their femur cross sections. this is corroborated by the fact that raw material (lithic) used for Mousterian tools was most often found within 5 km of the site where the tools made from it were discarded, while Aurignacian industries show a much higher proportion of exotic (>5km away) stone being used (Geneste 1988; Shreeve 1995; Mellars 1996).
Finally, palmar tuberosities in the carpal and phalangeal bones, while barely perceptible in modern humans are very apparent and noticeable in Neanderthal. This would have made Neanderthal fingers and thumbs upwards of twice the strength of modern humans Lumely-Woodyear 1973; Trinkaus 1983; Tattersall 1995). Tuberosities of distal phalanges being large and almost circular (Trinkaus 1981, 1983, 1991)indicating that they used their fingertips/nails on a regular basis for a wide variety of tasks such as grasping, pinching and kneading materials. It should also be noted that Neanderthal children were very robust at a very early age and so robusticity can be seen as genetic, and not an immediate environmental factor as some have surmised.
D.S. McDonald, 1996
TASTES LIKE CHICKEN
<![if !vml]><![endif]>Broken and cut human bones found scattered about three hearths in Moula-Guercy, a cave overlooking the Rhфne River in the Ardиche region of southeastern France, have confirmed that Neandertals practiced cannibalism 100,000 years ago. The 78 bone fragments, which have been dated at between 80,000 and 120,000 years ago, appear to have come from at least six individuals--two adults, two teenagers about 16 or 17 years old, and two children aged six or seven.
According to Tim D. White of the University of California at Berkeley, who has studied the bones, and French archaeologist Alban Defleur of the University of the Mediterranean, Marseilles, who has excavated the site since 1991, cut marks on the bones could have been made only by sharp flints. The skulls had been smashed open and limb bones had been broken apart, presumably to extract nutritious brain tissue and remove marrow. Only the hand and foot bones, which contain no marrow, remained intact. Cut marks indicate that tendons had been severed (necessary for limb removal), the thigh muscles removed, and in at least one case a tongue taken out.
No signs of gnawing were found on the bones, ruling out the possibility that the Neanderthals were eaten by wild animals. There were no signs of charring either, suggesting the flesh was either eaten raw or cooked off the bone. Scattered among the human remains were fragments of several animals butchered in the same manner, which were identified by Defleur's associate, Patria Valensi, as coming mostly from red deer.
"If we conclude that the animal remains are the leftovers from a meal, we're obliged to expand that conclusion to include humans," says Defleur. "It is not clear whether the individuals were eaten for survival when other food was scarce or as part of a social ritual," he adds, "but the abundance of natural resources available at the site when these individuals were killed makes the survival scenario seem highly unlikely."
Scientists have speculated for nearly a century that the Neanderthals practiced cannibalism. A cave in Croatia recently yielded a complete skeleton that had been stripped of all its flesh--to eat it before ritual burial of the bones some researchers have suggested. At Moula-Guercy, however, Defleur and White have found no evidence that would suggest the bones were cut and broken as part of a burial ritual.
"What is interesting is that while the Neandertal inhabitants at Moula-Guercy practiced cannibalism, their counterparts in the Middle East, most notably at Shanidar Cave in Iran and at Amud in Israel, were carefully placing their dead in burial pits along with tools and animal bone talismans. When you see some Neanderthals practising intentional burial and others practising cannibalism," says White, "is a clear indication of behavior that is multidimensional--a pattern that mirrors the behavior of more modern people." Defleur and White reported their findings in the October 1, 1999, edition of the journal Science.
An X-ray analysis of the famous 130,000-year-old Neandertal bones discovered a century ago in Krapina, Croatia, has revealed that our ancient cousins were far healthier that previously thought. Undertaken by physical anthropologist Alan Mann and a team of researchers from the University of Pennsylvania, the study of 884 bone fragments belonging to some 75 individuals showed that the Neandertal population was "osteologically healthy" aside from suffering from normal biomechanical wear due to day-to-day activities such as food-getting, aging, and injury. "We were able to document one of the earliest benign bone tumors ever found--on a rib; one individual may have had a surgical amuputation of a hand; and several individuals suffered from osteoarthritis, which may have made them a little stiff in the morning."
According to Mann, the X rays corrected some errors in the original descriptions of the Krapina assemblage. Nine specimens turned out to be animal bones not human, while 37 bone fragments, initially thought to be animal were identified as hominid.--ANGELA M.H. SCHUSTER
HOMO ERECTUS SURVIVAL
New dates for Homo erectus fossils from Ngandong, Java, suggest this hominid lived as recently as 53,000 to 27,000 years ago. The dates, obtained by Carl Swisher of the Berkeley Geochronology Center and colleagues, add to the debate between those who favor an out-of-Africa model and those who adhere to a multiregional one. The former believe modern humans developed in Africa 150,000 to 100,000 years ago, then dispersed into the Middle East and Europe, where they replaced Neandertals by 30,000 years ago, and into Asia, where they replaced H. erectus. The alternative is that modern humans evolved from predecessors in various regions. Multiregional proponent Milford Wolpoff of the University of Michigan holds, for example, that modern Australians owe certain characteristics to H. erectus forebears. The models, when first presented, were thought to be mutually exclusive.
If confirmed, the new dates for H. erectus contradict the multiregional model in its original version and support the replacement one. Some scholars, including Jean-Jaques Hublin of the Musйe de l'Homme, Paris, support a milder version of the replacement model in which different scenarios could have occurred in different regions. Some areas, such as Western Europe, would have experienced a total or almost total replacement. In other places, and possibly in the Far East, some level of gene flow could have occurred between local archaic populations and modern humans.
The Ngandong crania are widely accepted as H. erectus but have higher vaults than earlier H. erectus from Java or China. This is consistent with their late age. Wolpoff would simply consider them intermediate between local H. erectus and modern Australian, which the new dates make difficult to accept. In the replacement model, however, one must still explain the Ngandong cranial features, either as some degree of convergent evolution in Asian H. erectus and H. sapiens or some gene flow between them.
"It is rather striking to see that this overlap between long-lasting archaic populations and modern humans is documented only at the two extremities of the Old World, in the two culs-de-sac which are Western Europe and Indonesia," says Hublin. "In both places, each year brings new evidence of the possible interaction between contemporary but different groups of humans."--MARK ROSE
Discovered in 1992-1993, skull 5 from the Sima de los Huesos is the most complete premodern human skull ever found; model based on it has receding forehead, broad nose, and swept-back cheeks. (Reconstruction: Raul Romanillos; photographs: Javier Trueba/Madrid Scientific Films) [LARGER IMAGE]
model based on the reconstruction of skull 5, the best-preserved fossil skull of a premodern human ever found shows, for the first time, just how different from modern humans they were. Found in the Sima de los Huesos or Pit of Bones in northern Spain--one of several sites in the Sierra de Atapuerca--the more than 200,000 year-old skull is the most accurate view of what the early humans who gave rise to the Neandertals looked like.
According to most paleoanthropologists, Homo heidelbergensis gave rise to modern humans in Africa and Neandertals in Europe. Fossils such as the Mauer mandible and the skull from Tautavel place this divergence before 500,000 years ago. Differences between Neandertal DNA, recently recovered by scientists working in Germany and the United States, and DNA of modern humans place the separation between 690,000 and 550,000 years ago. (Amйlie A. Walker) [LARGER IMAGE]
or the first time, DNA of a premodern human has been recovered. Svante Pддbo of the University of Munich and colleagues in Germany and the United States successfully extracted the DNA from a right humerus (upper arm bone) of a Neandertal. Their findings, presented in the July issue of the journal Cell, provide important information about when Neandertals and modern humans diverged from a common ancestor, the nature of interaction between Neandertals and modern humans, and the ultimate fate of the Neandertals.
The humerus was found by quarry workers in the Feldhofer Cave, near Dusseldorf, Germany, in 1856, along with the top of a cranium, two femurs (upper leg bones), right radius and ulna (lower arm bones), part of the left ilium (pelvis), and fragments of a shoulder blade and ribs. The Neander Valley, in which the cave was located, later gave its name to the early human represented by these and other remains. The Feldhofer fossils are believed to date from between 40,000 and 50,000 years ago. They are now in the Rheinisches Landesmuseum in Bonn, which permitted removal of a 3.5 gram sample from the humerus for analysis.
As an initial test, amino acids from the bone were examined to determine whether or not DNA might be preserved in the sample. Degradation of amino acids and DNA is caused by the same factors, including water and temperature. Thus the condition of amino acids in bone, which is easily determined, can be used as a guide to the condition of any DNA preserved in the sample. The results were encouraging, and the scientists decided to attempt recovering and replicating DNA from the bone. To be certain of the results, each step in the analysis was repeated in Pддbo's lab and the findings were then duplicated independently by Mark Stoneking and Anne Stone at Pennsylvania State University.
The researchers focused on DNA from the mitochondria, organelles within cells, rather than from the nucleus. Mitochondrial DNA is more abundant than nuclear DNA, and is thus more likely to be recovered in sufficient amounts to allow replication. In addition, mitochondrial DNA is transmitted only from the mother so that changes from generation to generation result from mutation alone rather than recombination of the mother and father's DNA. The scientists obtained a sequence of 379 amino acid base pairs by replicating shorter, overlapping segments. They identified 27 differences between the Neandertal DNA and a modern reference DNA sample over the replicated sequence. By contrast, DNA from a random sample of a modern population might vary from the reference DNA in five to eight places.
DNA dating is based on the assumption (debated by geneticists) that mutations occur at a constant rate. The accumulated mutations in DNA can be measured, and the time necessary for them to occur calculated. The amount of difference between Neandertal and human DNA suggests that our common ancestor existed about 550,000 to 690,000 years ago. Although this date must be qualified (it is based on one specimen only, and the DNA clock may or may not be as accurate as we assume), it is in accord with the fossil record. Osteological characteristics of the 300,000-year-old remains from the Sima de los Huesos in northern Spain (see "Faces from the Past," ARCHAEOLOGY, May/June 1997) and the 400,000- to 500,000-year-old jaw from Mauer, Germany, indicate that these humans, generally classified as Homo heidelbergensis, are ancestral to Neandertals. This suggests the split between the ancestors of modern humans and Neandertals had occurred somewhat earlier, about the time indicated by the new DNA date.
The relationship between Neandertals and modern humans, who are thought to have arisen in Africa some 120,000 to 150,000 years ago, and the demise of the Neandertals are intertwined. The two coexisted in Southwest Asia for a long period (see "The Peopling of Eurasia," ARCHAEOLOGY, January/February 1996). Excavations at sites in Israel have yielded remains of modern humans at Skhul and Qafzeh caves dated from as early as 120,000 to 90,000 years ago, and Neandertal remains at Kebara Cave dated from 60,000 years ago and Amud Cave dated from 40,000 to 50,000 years ago. In western Europe, Neandertals persisted until 30,000 years ago and possibly somewhat later. The question arises: To what extent did the two interact in terms of cultural exchange or trade and interbreeding? Were the Neandertals out-competed by modern humans or killed off by them, or were they absorbed into the population and genetically swamped? At Arcy-sur-Cure, in France, stone tools and personal ornaments similar to those associated elsewhere with modern humans have been found with 34,000-year-old Neandertal remains, suggesting trade between the two groups. Despite this evidence for cultural exchange, a study of temporal bones from Arcy-sur-Cure and other sites indicates significant differences between Neandertals and modern humans, suggesting interbreeding did not occur (see "Neandertal News," ARCHAEOLOGY, September/October 1996).
If Neandertals made a significant genetic contribution to modern humans, similarities should exist between DNA of Neandertals and that of people from Europe, where the Neandertals persisted the longest. Pддbo and his colleagues compared the Neandertal DNA to that from five modern populations, but it proved no closer to DNA from modern Europeans than to that from four other groups. While this does not rule out the possibility of Neandertal and modern human mixing, it suggests that the Neandertal genetic contribution to modern gene pools, if any, was small.
Setting aside the particulars of this new study, the fact that it was possible to recover Neandertal DNA is a breakthrough itself and opens many possibilities for similar investigations. Mammoth remains preserved in the Siberian permafrost have yielded DNA from 50,000 to 100,000 years ago, but preservation of DNA more than 100,000 years old is thought to be unlikely. While DNA from a pre-Neandertal form, like the Homo heidelbergensis from Atapuerca, will probably never be recovered, it would be interesting to compare DNA from early Homo sapiens and Neandertals from Southwest Asia where the two coexisted for such a long period. Another intriguing possibility would be to compare later Homo sapiens and the last of the Neandertals, those from 30,000 years ago, found at western European sites like Zafarraya Cave in southern Spain. The fossils from Feldhofer belong somewhere in the middle period of Neandertals. Would DNA from different regions and periods confirm the results obtained from this study, or would they suggest other degrees of interaction? The recent claim that Homo erectus was alive in Southeast Asia as recently as 53,000 to 27,000 years ago (see "Homo erectus Survival," ARCHAEOLOGY, March/April 1997), makes it conceivable that DNA from this species could also be recovered.--MARK ROSE
The extraction of mitochondrial DNA from a Neanderthal fossil has caused considerable discussion recently. Neanderthals are a group of hominids very close to human beings, and in fact, are often considered to be human beings. The DNA results tend to suggest that Neanderthals are intermediate between humans and apes. Is this conclusion justified?
Some data about this result are given in an article in Science vol. 277 July 11, 1997, pp. 176-178. The method used to extract the DNA was the polymerase chain reaction, which on old and damaged DNA is highly error prone. The DNA was in fragments about 100 base pairs long, which had to be pieced together into a region 379 base pairs long. This process of piecing together took three months of work. Among the fragments found were some that looked like modern human DNA, and these were considered to be contamination.
This process was done twice, and the same sequence was obtained both times. The resulting sequence was compared with 986 distinct sequences from living humans. The sequence differed from these in an average of 25.6 positions. Living humans differ in this region in an average of 8 positions, but the maximum difference is 24 positions. But the pattern of mutations in the Neanderthal sequence was different than in modern humans. For comparison, in this region, there are 55 differences between humans and chimpanzees.
It seems that there is still room for interpretation concerning the accuracy and validity of this result. Even if the Neanderthal sequence is correct, one needs to consider whether these mutations result from evolution or from some environmental factor. Furthermore, there is still considerable controversy about the existence of the missing links. In addition, "some of the Neanderthals get more severe in their archaic morphology as they approach the end of the Neanderthal sequence, the opposite of evolutionary expectations," according to Dr. Marvin L. Lubenow, creationist author of Bones of Contention. This would seem to indicate that the Neanderthals were degenerating and not evolving to become more fit. This could indicate that these mutations were the result of some environmental factor.
Another point to consider is the implication of the mutation rates assumed for human evolution. Typical rates of mutation assumed for human ancestors are about one substitution per base pair every 200 million years. (See Mol Biol Evol 1985 March; 2(2):150-174.) (Actually, many different figures are used, and the real rates of mutation are unknown. This rate is based on assumed evolutionary time scales.) Assuming 10 percent of the human genome codes for protein, this means about 300 million base pairs code for protein. This would give on the average 300 million substitutions every 200 million years. Probably 2/3 of these would influence the protein coded, and 1/3 would be silent, leading to 200 million harmful mutations in 200 million years, about one a year. With a generation time of 30 years, this is an average of 30 harmful mutations per offspring for humans from each parent, or 60 in all. The chance of an offspring being free from harmful mutations is then 1/(2.718) 60 , which is astronomically small. This would imply that the human race is rapidly degenerating. Some of these mutations might be recessive, but in 10,000 generations or so, their frequency should increase enough so that this effect should be realized. In fact, when the population reaches equilibrium, we should expect only about one in 2.718 60 fertilized eggs to survive, at this mutation rate. A justification for this calculation method as well as other calculations which are problematical to the theory of evolution can be found here (near the end) and here.
THE GREAT DNA HUNT
BY TABITHA M. POWLEDGE AND MARK ROSE
DNA can be used to understand the evolution of modern humans, trace migrations of people, identify individuals, and determine the origins of domestic plants and animals. DNA analysis, as one scholar put it, is "the greatest archaeological excavation of all time." Because ancient DNA molecules are normally so few and fragmented, and preserved soft tissues so rare, scientists had little hope of finding and analyzing it. But two breakthroughs have made this possible: the polymerase chain reaction (PCR), a method for copying any fragment of DNA, and the successful recovery of DNA from preserved hard tissues, bones and teeth, that are durable and relatively abundant.
DNA analysis traced human ancestry back to an African "Eve," setting off debate about how modern humans evolved. While there was general agreement that Homo erectus dispersed from Africa across Asia between 1 and 2 million years ago, what happened next remained a question. The "out-of-Africa" hypothesis contended that modern humans developed in Africa and migrated from there recently, driving H. erectus into extinction. Proponents of a "multiregional" hypothesis held that H. erectus populations evolved into modern humans in many regions, and that these groups later bred with each other and with groups that emigrated from Africa. The Eve study examined mitochondrial DNA (mtDNA), which is passed only by mothers to their offspring. The researchers, Rebecca Cann, Mark Stoneking, and the late Allan Wilson, estimated that the ancestor of all surviving mt DNA types lived between 140,000 and 290,000 years ago. When did the migrations from Africa take place? They dated the oldest cluster of mtDNA types with no modern African representation to between 90,000 and 180,000 years ago. These populations might have left Africa at about that time, but the mtDNA data could not determine exactly when.
Geneticist Alan Templeton pointed out statistical and sampling flaws in the study. Its results, he argued, were in part dictated by the order in which the data were fed into the computer. Others questioned the reliability of "molecular clocks" and the rate of mutation in the human mtDNA used in calculating Eve's date. The genetic diversity of African populations was confirmed by later studies and is now generally accepted, but, according to Templeton, proponents of the out-of-Africa hypothesis assumed that genetic diversity reflected only the age of a population rather than population size. He contends that Africa has greater genetic diversity because its prehistoric population was probably larger than elsewhere. Recently John Relethford and Henry Harpending have argued that differences in ancient population size could mimic a recent African origin of modern humans. The data reflect population dynamics, they say, and do not support one model of modern human origins over another.
Scientists are also studying DNA from the Y chromosome, which is passed only from father to son and is not recombined with the mother's genes. Because changes in the Y chromosome are caused only by mutations, as in mtDNA, it may be used as a clock. Assuming that all living humans share a common male ancestor, it should be possible to estimate when he lived. According to geneticist Robert Dorit, the first modern human male lived some 270,000 years ago. The most recent research on modern human origins, by John Armour, examined nuclear DNA of populations from around the world. Armour and his colleagues conclude that the evidence fits with the development of modern humans in Africa and an emigration by a small number of them that became the basis for non-African populations. These observations, they say, are more difficult to reconcile with a multiregional model for the origin of modern humans.
New DNA studies by Bryan Sykes have challeneged the leading theory about the spread of agriculture into Europe. In 1984 Albert Ammerman and geneticist Luigi Luca Cavalli-Sforza of Stanford University proposed that it was people practicing agriculture who spread into Europe, rather than the idea of agriculture. They argued that agricultural productivity led to population growth, and that, as the population grew, early farmers gradually moved into new land inhabited by fewer hunter-gatherers. Thus the practitioners of agriculture spread from Anatolia, beginning about 7000 B.C., to Greece and across all of Europe, ending in Britain and Scandinavia about 4000 B.C. Using mtDNA analysis, Sykes claims that the ancestors of most modern Europeans arrived at least 20,000 years ago, long before the supposed arrival of Neolithic farmers. In analyzing mtDNA from more than 800 modern Europeans, Sykes and his colleagues identified at least five main groups. Four of the five groups date to well before the last glacial peak, with ages ranging from 35,000 to 25,000 years ago. The fifth group is much younger in Europe (6,000 to 10,000 years ago) and has clear affinities to Near Eastern mtDNA. Sykes and his colleagues accept this as the genetic echo of the spread of agriculture, but note that it is fairly weak. They conclude that, far from being overwhelmed by incoming farmers, the indigenous hunter-gatherer population remained intact and learned how to farm.
Documentation of the early presence of Caucasian people in northwestern China, and information about their affinities with either modern European or Indo-Iranian populations, could contribute to the debate about the spread of Indo-European languages. Chinese and Uyghur archaeologists have been excavating naturally mummified bodies there since the 1970s. Paolo Francalacci of the University of Sбssari, Sardinia, took samples from several of the bodies, dated to 3,200 years ago DNA analysis for these mummies suggest a possible European origin, although further research is needed to identify them more precisely. As part of a larger project, Chinese geneticist Du Ruofu has been collected samples of mtDNA from modern Tarim Basin populations. Comparison will determine how much of the ancient genetic composition survives.
Most scholars believe that people from the Asian continent came to the Japanese archipelago in two migrations. An early wave brought the Jomon culture--hunter-gatherers who made pottery--to Japan more than 10,000 years ago. A second migration began about 2,300 years ago, when the Yayoi people, entering from the Korean Peninsula, brought weaving, metalworking, and rice culture to Japan. First appearing on the southwestern island of Kyushu, by ca. A.D. 300 Yayoi culture had spread throughout most of Japan, altering all local cultures south of Hokkaido, the northernmost island. Michael F. Hammer and Satoshi Horai are examining the extent to which the Jomon did or did not contribute genetically to the modern Japanese. Current hypotheses can be classified as replacement, hybridization, or transformation. In the first, Yayoi immigrants replaced the Jomon people. Hybridization theories claim that modern Japanese are descended from both groups, in which case they should have genes deriving from both the Jomon and Yayoi people. Transformation theories posit that modern Japanese people gradually evolved from the Jomon. Hammer and Horai, based on their study of the Y chromosome, conclude that hybridization, a mixing of Jomon and Yayoi stocks, is the most likely explanation for the origin of modern Japanese.
Nonhuman DNA has great potential for shedding light on cultural practices. Recent work by Daniel Bradley is a case in point. Before now it was assumed that cattle were first domesticated in the Near East. African, European, and Indian cattle were all thought to be descended from a domesticated Near Eastern progenitor, and to have developed into characteristic breeds afterward. Bradley and his colleagues have determined that Indian cattle broke off from an ancestral lineage between 117,000 and 275,000 years ago. The lineage split again about 22,000 to 26,000 years ago into groups that gave rise to modern African and European cattle. These are startling results because cattle in the Near East were not domesticated until about 9,000 years ago, and cattle in India and Africa were genetically distinct before then. The latter two could not possibly be descended from domesticated Near Eastern cattle, as was thought, but must have been domesticated independently.
Geneticist Terence A. Brown and his colleagues have devised a way to identify types of wheat using DNA analysis. This will make it possible to determine whether primitive wheats or modern varieties were grown at a site. The higher productivity of modern varieties means that a larger population could be supported, and fewer people had to be involved in farming. This may have been a factor that sustained the rise of classical civilizations. Brown also hopes to use similarities and differences in wheat DNA to investigate the relationships between Celts and Romans in Britain. Did the Romans bring their own wheat, or did they rely on indigenous agriculture to support the Roman community?
Krings, M; Stone, A; Schmitz, R W; Krainitzki, H; Stoneking, M; Paabo, S.
Neandertal DNA sequences and the origin of modern humans
Cell 90 (1997): 19-30.
Authors' abstract: DNA was extracted from the Neanderthal-type specimen found in 1856 in western Germany. By sequencing clones from short overlapping PCR products, a hitherto unknown mitochondrial (mt) DNA sequence was determined. Multiple controls indicate that this sequence is endogenous to the fossil. Sequence comparisons with human mtDNA sequences, as well as phylogenetic analyses, show that the Neanderthal sequence falls outside the variation of modern humans. Furthermore, the age of the common ancestor of the Neanderthal and modern human mtDNAs is estimated to be [around 600,000 years, or] four times greater than that of the common ancestor of human mtDNAs . This suggests that Neanderthals went extinct without contributing mtDNA to modern humans.
Next to our own selves, there is no more interesting hominid than the Neandertal. Neandertals are the humans manquй, the evolutionary dead end: eerily like us, but different in major ways. And they are the subject of one of the hottest ongoing debates in anthropology.
How smart were these big-brained, stocky-bodied people, who inhabited Europe and the Middle East starting about 200,000 years ago? And what caused their relatively abrupt disappearance by 30,000 years ago? The Neandertals' reputation has oscillated over the years, and new evidence has sharpened the debate. Genetic data suggest a sizable gulf between Neandertals and modern humans, while recent discoveries hint that Neandertals had a brief technological golden age before vanishing.
Last year, DNA testing of a Neandertal bone showed that these beings probably branched off the human line a half-million years ago, perhaps qualifying them as a separate species (Science, 11 July 1997, p. 176). But other lines of evidence have encouraged speculation that they may have been like us in one crucial respect: speech. One is the discovery in 1989 of a Neandertal hyoid bone--the bone that supports the larynx--in Kebara cave in Israel. Because it is a lot like a human one, it indicates, says archaeologist Francesco d'Errico of the Institute of Quaternary Prehistory and Geology in Talence, France, that "Neandertal abilities were also quite similar."
Earlier this year, anthropologists at Duke University reinforced that notion with a comparative analysis of the hole that carries motor nerves to the tongue, called the hypoglossal canal, in several hominid skulls. Chimp-sized in the 2-million-year-old australopithecines, the canal is significantly larger, falling in the modern human range, in both Neandertals and an earlier, 300,000-year-old skull. This suggests that "the vocal capabilities of Neandertals were the same as those of humans today," Richard Kay and colleagues wrote in the 28 April Proceedings of the National Academy of Sciences.
Cognitive scientist Philip Lieberman of Brown University disputes these claims. First, he says, you can't predict tongue shape--the critical factor for modern speech--from an isolated hyoid bone. Moreover, he says the Duke team based their calculations of the relative sizes of different species' hypoglossal canals on incorrect estimates of human tongue size and shape. Lieberman himself argues, from his 1971 analysis of a Neandertal skull from Chapelle-aux-Saints in France, that proportions such as the distance between the hard palate and the spinal column would have made it impossible for Neandertals to speak with the clarity modern humans possess.
Kay says that his finding still holds, and that Neandertals might have had speech "in every way as complicated as modern humans." But others say Lieberman's conclusions are reinforced by Neandertals' other behavioral limitations. Harold Dibble of the University of Pennsylvania, Philadelphia, for example, says "the lack of art and the lack of clear evidence of symboling suggests that the nature of [Neandertal] adaptation [to their environment] was significantly different" from that of their successors. The difference shows up, for example, in their stone tools.
Neandertals could do stone-knapping with the best of them, says Stanford University archaeologist Richard Klein. But over thousands of years this practice never seemed to lead to clear differentiation in types of tools. "They didn't make tools in the [different] standardized patterns you see later," coming from the modern people who arrived in Europe about 40,000 years ago, says Klein. To him this difference suggests that the Neandertals "were only interested in a point or an edge" rather than conceptualizing a particular product.
Then there is the Neandertal hunting record. In a special Neandertal supplement of the journal Current Anthropology in June, for example, archaeologist John Shea of the State University of New York, Stony Brook, defends Neandertal hunting prowess. He argues that their tool assemblages show they engaged in "intercept" hunting, which would require a knowledge of animal migration routes. On the other hand, according to Erik Trinkaus of Washington University in St. Louis, the high rate of broken bones and early death among Neandertals suggests that they engaged in more close-quarter combat with large animals than did modern humans, who had figured out safer strategies.
In the past, some have claimed that Neandertals held ritual burials, which would have implied highly developed social behaviors and possibly even religion. But that belief was largely based on a 60,000-year-old Neandertal burial at Shanidar cave in Iraq, where pollen grains were taken to imply that the body had been covered with flowers. Many scientists now believe the plant material is an incidental intrusion. In reality, "the number of claimed Neandertal burials is extremely low," and none has yielded convincing evidence for grave goods, says Dibble.
As archaeologists learned in 1996, however, the Neandertals in France and Spain showed surprising new talents at the end of their evolutionary career after 40,000 years ago. They began making more sophisticated and diverse tools, and even, at one site, an array of beads and pendants (see p. 1451). These artifacts have led to a new surge of debate over whether Neandertals were finally expressing their symbolic potential or were just imitating their modern human neighbors.
Whatever the answer, it may have been a case of too little, too late. For shortly after that, the Neandertal record vanishes. What drove them to extinction? Many scientists say that even without a difference in brainpower, the Neandertals would have been at a disadvantage. Archaeologist Ezra Zubrow of the State University of New York, Buffalo, has made a mathematical model based on skeletal data on the life-spans of the two populations. From it he concluded that with only a slight disadvantage in life expectancy, "it was easy to drive Neandertals to extinction under a wide range of conditions" because of their small populations. Shea adds that with their heavy frames and active lifestyle, their voracious energy needs might have hurt them "in competition with more energetically efficient modern humans."
Debates about Neandertal abilities have become colored with notions of political correctness, say archaeologists. "I've been accused of being racist for saying the Neandertals couldn't speak like us," says Lieberman. Clive Gamble of the University of Southampton in the U.K., for one, doesn't understand why people need to make Neandertals something they weren't. "Neandertals are fantastic ways of realizing the alternative ways of humanness."
Sometime around 250,000 years ago, an early human living on the Golan Heights in the Middle East picked up a lump of volcanic tuff the size of a plum and started scratching at it with a harder stone, deepening its natural crevices. Not long afterward, a volcanic eruption buried the soft pebble in a bed of ash, preserving it from erosion. A quarter of a million years later, in 1980, archaeologists dug it up, and since then, the pebble has been the object of rapt attention--far more, perhaps, than it got when it was new. By chance or design, those long-ago scratchings created what looks like a female figure--and a puzzle for the archaeologists who study the beginnings of art.
To many archaeologists, art--or symbolic representation, as they prefer to call it--burst on the scene after 50,000 years ago, a time when modern humans are widely thought to have migrated out of Africa to the far corners of the globe. These scholars say the migrants brought with them an ability to manipulate symbols and make images that earlier humans had lacked. An explosion of art resulted, its epicenter in ice age Europe starting about 40,000 years ago, when most anthropologists believe modern humans were replacing the earlier Neandertal people. The new Europeans decorated their bodies with beads and pierced animal teeth, carved exquisite figurines from ivory and stone, and painted hauntingly lifelike animals on the walls of deep caves.
Some recent discoveries have strengthened this picture. Hints of art and personal ornaments have been found in Africa from just a few thousand years before the artistic explosion in Europe, supporting the idea that a worldwide migration of protoartists did begin 50,000 years ago in Africa. As Richard Klein of Stanford University puts it, "There was a kind of behavioral revolution [in Africa] 50,000 years ago. Nobody made art before 50,000 years ago; everybody did afterward."
But other developments have raised awkward questions about this "big bang" theory of art, as some critics call it, hinting that art and the sophisticated cognitive abilities it implies may have a longer history. After years of doubt, most archaeologists accept that the so-called Berekhat Ram object from the Golan Heights is the work of human hands, although there is no consensus about what--if anything--it means. Neandertal sites in Europe, some of them well over 40,000 years old, have yielded a polished plaque split from a mammoth tooth, bones that may have been incised for decorative purposes, and layers of ochre--a red pigment that early humans may have used to decorate their bodies. Ochre is also abundant at early sites in Africa, and ochre "crayons" have turned up at ancient rock-shelters in northern Australia, in layers that may be nearly 60,000 years old. "We're seeing more and more of these things popping up all over the place," says Paul Bahn, an independent archaeologist in England.
And 3 years ago, cave art specialists were stunned when carbon dating showed that virtuoso paintings at Grotte Chauvet in France may be more than 32,000 years old, meaning they were created not long after modern humans arrived in Europe. "I simply cannot conceive of the Grotte Chauvet paintings appearing out of nothing," says Bahn.
Perhaps most telling, many archaeologists now think an array of grooved teeth and other ornaments from a cave called the Grotte du Renne, at Arcy-sur-Cure in central France, is the handiwork of Neandertals. The age of the Arcy deposits is in dispute; most archaeologists think they date to around 35,000 years, a time when modern humans were already spreading into Europe and making stunning art of their own. But the date could be as early as 45,000 years ago, before modern humans arrived. To some researchers Arcy puts the lie to arguments that nonmodern humans like the Neandertals did not--perhaps could not--express themselves in art and ornament. It supports the view that artistic habits going back tens or even hundreds of thousands of years could have prepared the ground on which the ice age explosion took place.
The debate is more about the significance of this early evidence than about its reality. Traditionalists--call them explosion theorists--don't doubt that humans before 50,000 years ago sometimes left artifacts that appear decorative or symbolic. But they argue that the objects are so rare and crude that they can hardly be taken seriously as part of a systematic symbolic representation of the world. As Paul Mellars of the University of Cambridge puts it, "Everything that's ever claimed to be Neandertal is so amorphous, so lacking in crisp representation. ... There's always this massive question of whether it's just someone doodling." What impresses him, he says, "is the contrast between that and the clarity you get in the Upper Paleolithic"--the time after 40,000 years ago when modern humans populated Europe.
Art's big bang
Even for archaeologists who focus on earlier times and other continents, there's no denying the artistic explosion that took place in ice age Europe. Some of the earliest confidently dated signs, from a site called Kostenki 17 in Russia, are 38,000-year-old beads and pendants of stone, animal teeth, and marine fossils. After that, ornaments and imagery proliferated. In well-dated 35,000-year-old deposits at a rock-shelter called Abri Castanet in southwestern France, says Randall White of New York University, "I have more material in a few square meters than [there is] in all the rest of the world up until then."
The ornamental objects at Abri Castanet are beads--thousands upon thousands of them, in all stages of manufacture, made of mammoth ivory and soapstone. And within a few thousand years, the artistic range of these first modern Europeans had broadened to expressive carvings of animals, enigmatic figurines of women in the last stages of pregnancy, and the painted lions, rhinos, bears, and other animals that romp across the walls at Grotte Chauvet. "Between 38,000 and 33,000 years, everything is there, including Grotte Chauvet," says White.
But what could have touched off this explosion? Klein and a few others think the answer lies in biology--some change in the wiring of the brain that enabled humans to innovate, think symbolically, and make art. "My view is that modern human behavior was a biological advance," he says. Human ancestors in Africa looked anatomically modern by 150,000 years ago. But Klein thinks an additional evolutionary step, hidden in the brain, came 50,000 years ago. It gave modern humans the cognitive wherewithal to migrate to the distant reaches of Europe and Asia, replacing archaic human populations as they went.
And, gratifyingly for Klein, Africa is where some of the earliest indisputable body ornaments are turning up. In last April's Journal of Archaeological Science, Stanley Ambrose of the University of Illinois, Urbana-Champaign (UIUC), describes his excavations at a rock-shelter in the Rift Valley of Kenya, at a site called Enkapune Ya Muto. There he found a cache of beads made of ostrich eggshell, blanks, and shell fragments. Some of the beads, says Ambrose, "are shiny, obviously worn, as if someone was wearing them as part of some ornament." They must have served as symbolic markings, he says, "expressing an awareness of the self and how to enhance it."
It's the same phenomenon seen in Europe 38,000 years ago--but it may be several thousand years earlier at Enkapune Ya Muto, says Ambrose, who has carbon-dated the shells and come up with an age of at least 40,000 years. "These early ostrich eggshell beads are perhaps the earliest indicator" of symbolic behavior anywhere, says Klein. "And it's very important that they first appeared in Africa," just as expected if the crucial biological innovation had occurred there.
Other archaeologists agree with Klein about the sudden flowering of art but reject his biological explanation. "I don't think it's a mutation for the art gene," says Olga Soffer of UIUC. "We're totally on the wrong track when we're asking the question of biology." White agrees. "I think that what we call art is an invention, like agriculture, which was an invention by people who were capable of it tens of millennia before."
What spurred the invention is a matter of speculation, although many archaeologists think that, at least in Europe, it could have been part of a social change triggered by a challenging new environment. Chasing wide-ranging herds in the shadow of the ice sheets, modern humans thrived by developing an intricate social system, with a complex division of labor and long-distance ties. "That's one way to survive in an environment where you've got scattered and somewhat unpredictable resources," says Philip Chase of the University of Pennsylvania, Philadelphia. Body ornaments and art might have helped express those new social relations.
Or they may have served to distinguish modern humans from the other kinds of people they were meeting as they moved into new and perhaps hostile territory. Says White: "I have a hard time thinking it's coincidental that all of this was going on [in Europe] at a time when you have quite a different hominid moving into territory occupied for 300,000 to 400,000 years [by earlier humans]. A major concentration of art is right where Neandertals were being replaced by modern humans, all the way from the Russian plain to the Iberian peninsula." Modern humans naturally sought ways to distinguish themselves from their neighbors and strengthen their own cultural ties, he suggests, and art was one solution.
It's old, but is it art?
A few researchers, however, think they have a more natural explanation for the ice age explosion: It was grounded in a tradition going back tens or even hundreds of thousands of years and glimpsed fitfully in sites around the world. Alexander Marshack, for instance, an archaeologist associated with the Peabody Museum at Harvard University, has campaigned for years to persuade his colleagues that ice age Europe can't be the beginning of the story.
Thirty years ago, he took his first close look at 30,000-year-old ivory animals from Vogelherd, in Germany, then considered to be some of the earliest art. What he saw, he says, were works "so sophisticated they couldn't have happened instantaneously. Making them required thousands of years of technology, of symboling, of making stories about the animals." Early cave paintings also showed signs of a rich cultural context that, he believed, simply could not have emerged full-blown in a few centuries. Other archaeologists argue that a few centuries is plenty of time for culture to blossom. But Marshack concluded that "there had to be a long prior history, so I began looking for earlier objects."
Here and there, in material from sites around the world, he has found them. From Quneitra in Israel comes a bit of flint incised with concentric arches some 54,000 years ago. From a site called Tata in Hungary comes an enigmatic plaque made of polished mammoth tooth, 50,000 to 100,000 years old, its crevices filled with red ochre. At a 250,000-year-old rock-shelter site in the Czech Republic, archaeologists found a bed of ochre and the rubbing stone used to make the powder--not art, but perhaps the means of making it. And then there is the 250,000-year-old carving from Berekhat Ram, which Marshack has studied closely and interprets as the figure of a woman with an elaborate coiffure.
To Marshack, the Berekhat Ram object, like the later artifacts from Tata and Quneitra, is a trace of a capacity for making symbols that was well developed long before the ice age explosion. True, he says, it's just one piece of "art" from a span of tens of thousands of years, but it should not be dismissed. "It may be unique, but its complexity raises questions that have to be addressed." It suggests, he adds, that other symbolic objects have simply been lost from the record: "Chances are that if they were making images of volcanic tuff, they were making images of wood," which would have decayed. One reason ice age art is so abundant, he adds, is that modern humans in Europe worked durable materials such as mammoth ivory and bone.
Marshack isn't the only one coming up with such evidence. A smattering of suggestive artifacts have come from Neandertal sites in Europe and Russia: bits of bone with what look like decorative markings, even a 43,000-year-old bone "flute" from Slovenia. But many of those claims have withered as researchers including Francesco d'Errico and Paola Villa of the Institute of Quaternary Prehistory and Geology in Talence, France, have taken a close look at the artifacts. Animal digestion, butchery marks, and even the tracks of blood vessels can easily explain many of the bone markings, says d'Errico. And both d'Errico and Chase have concluded that, as d'Errico puts it, the supposed flute "is absolutely natural and is the result of gnawing by animals."
Some of Marshack's artifacts, however, have held up better. His analysis of the Berekhat Ram object, published last year in Antiquity, seems to have convinced most of his colleagues that it was shaped artificially, and a few of them even accept it as an image. "It's extremely clear that it's humanly enhanced. It's definitely an art object," says Bahn. D'Errico and April Nowell of the University of Pennsylvania, Philadelphia, actually tested Marshack's claims by going to the site and comparing the object with hundreds of other bits of tuff. They, too, are persuaded that it is human handiwork. "No other pieces have this kind of modification," d'Errico says.
But he isn't ready to call it art. "I'm not sure the people who made the grooves were people using symbols. Also, one case does not explain a lot." Exactly, says Cambridge's Mellars. The uniqueness of artifacts like the Berekhat Ram carving "totally undermines their role in a symbolic communication system," he says. Chase sums up the doubts about Berekhat Ram and similar artifacts: "Was it just a kid who was sitting there scratching on something? Or did it have some function we can't recognize?"
One set of decorative objects apparently made by nonmodern humans can't be dismissed as anomalies, however. At the Neandertal site of Arcy-sur-Cure, archaeologists in the 1950s and 1960s excavated not just one or two but dozens of animal teeth pierced and grooved for use as ornaments, along with a handful of ivory beads and pendants. No other Neandertal site has held anything like this trove of symbolic objects. The same site also yielded bone tools and stone points made by more modern techniques than those of earlier Neandertals. But most of the doubts about whether Neandertals were responsible for these objects faded when Neandertal bones were identified first at another site with the same "Chвtelperronian" tool technology and then, 2 years ago, at Arcy itself.
Now archaeologists are debating what the Neandertal ornaments at Arcy mean for the ability of nonmodern humans to traffic in symbols and make art. Although the exact age of the Arcy deposits is uncertain, most carbon dates from the site overlap with dates for modern humans in France and Spain. That leaves plenty of room for archaeologists to argue over whether the Arcy Neandertals developed art on their own or were imitating their trendy neighbors.
At one pole is Joгo Zilhгo of the University of Lisbon in Portugal, who published an assessment of Arcy with d'Errico and others in the June issue of Current Anthropology. Zilhгo says that at other Chвtelperronian sites, the Neandertal deposits always underlie the layers of artifacts left by modern humans, implying that the Neandertal activity came first. And he puts his money on the earliest of the widely varying carbon dates obtained from the layers at Arcy, roughly 45,000 years old--a date that would mean the Neandertals made the objects well before modern humans were around to set an example. Zilhгo says the evidence is clear: "Strictly empirically, Neandertals invented [ornaments] first."
At the opposite pole is Paul Mellars, who says Zilhгo is wrong about the timing. "Most if not all of the Chвtelperronian is post-38,000 radiocarbon years," he says. "It's a phenomenon that occurs after the arrival of moderns in northern Spain." The fact that Chвtelperronian artifacts are found below those of modern humans just shows, he says, that the moderns moved into the abandoned caves and rock-shelters after the Neandertals vanished. In the meantime, the two groups could have had plenty of contact along a frontier that probably ran along the Pyrenees, with Neandertals to the north and modern humans to the south.
It's there that the Neandertals would have taken their artistic cues from their new neighbors, says Mellars. "Here were these 'supermen' coming over the hill, wearing fancy beads, with better weapons, better hunting skills--the Neandertals would have to be staggered by this." They would inevitably try to copy what they saw, if only because the modern style, pierced fox teeth and all, had cachet. The artifacts that resulted should not be taken as a sign of an independent artistic capacity, says Mellars. "To say that the beads must have had exactly the same symbolic meaning to Neandertals as they did to moderns--that's a non sequitur."
Most archaeologists agree with Mellars about the timing. But some note that the Neandertal beads aren't direct imitations of what nearby modern humans were making. The people at Arcy chose different kinds of animal teeth and used different techniques to work them, which leads these archaeologists to suggest that the Neandertals were drawing inspiration from their neighbors rather than simply mimicking them--making beads in their own way, for their own cultural purposes.
If so, the Arcy deposits could still have unsettling implications for the idea that art, and the complex culture it implies, is unique to modern humans. Says Chase, "If this really is symbolism, and taken at face value it is, then you've got Neandertals who were capable of the same symbolic behavior as modern humans." Klein is also mystified. "I want the Neandertals to be biologically incapable of modern behavior. So [the Chвtelperronian] is a real problem."
Zilhгo and others hope to do more dating of the Arcy deposits, which might settle the issue if it shows that the ornaments really do predate modern humans in Europe. In the absence of such a tie breaker, the dispute will continue--pitting big bang theorists against gradualists, and archaeologists who stress the overall pattern of evidence against those who focus on the puzzling exceptions. After all, the real answer about what is art and what is not lies in the minds of its makers--and they are long gone.
The following is a selected bibliography with an emphasis on Neanderthal. It is by no means complete, but offers the reader a good start. There is material for the lay-audience as well as works for serious university researchers. If you know of a relevant work that is not posted, please email me and I will endeavour to include it. This list will be continually added to as new sources come to light.
For archaeological fiction enthusiasts, there is a fiction page where you might find some interesting novels. Also, check out the links page for a list of resources on the internet, including some exclusive online journals not listed below.
1974. ФThe evolution of social behavior.Х In:Annual Review of Ecology and Systematics 5: 325-383.
1983. ФSpatial patterning in the Middle-Upper Palaeolithic transition.ХWorld Archaeology. 15:224-235.
Bar Yosef, O. & Meignen, L..
1992. ФInsights into Levantine Middle Paleolithic cultural variability.Х In: The Middle Paleolithic: adaptation, behavior, and variability (eds H.L. Dibble & P.A. Mellars). Philadelphia: University of Pennsylvania University Museum Monographs No. 72, pp. 163-182
1989. 'European prehistory gets even older', SCI, 246: 28-30.
1985. Thermoluminescence Dating. London: Academic Press.
1990. Science-based Dating in Archaeology. London, Longman.
Aiken, M.J., Huxtable, J. & Debenham, N.C.
1986. 'Thermoluminescence dating in the Paleolithic: burned flints, stalagmitic calcite and sediment' in Chronostratigraphie et Faciиs Culturels du Palйolithique Infйrieur et Moyen dans l'Europe du Nord-Ouest (eds. A. Tuffreau & J. Sommй). Paris: Association Franзaise pour l'Etude du Quaternaire, pp. 7-14.
Aiken, M.J., Stringer, C.B. & Mellars, P.A. (eds)
1992. The Origin of Modern Humans and the Impact of Chronometric Dating. London: Royal Society (Philosophical Transactions of the Royal Society, series B, 337, no. 1280).
Ashton, N.M. & Cook, J.
1986. 'Dating and correlating the French Mousterian' in Nature 324: 113.
1989. 'Geochronology of the Levantine Middle Palaeolithic' in P. Mellars and C. Stringer (eds) The Human Revolution: Behavioural and Biological Perspectives on the Origins of Modern Humans, pp. 589-610. Edinburgh, Edinburgh University Press.
Bard, E., Hamelin, B., Fairbanks, R.G. & Zindler, A.
1990. 'Calibration of the 14C timescale over the past 30,000 years using mass spectrometric U-Th ages from Barbados corals' in Nature 354: 405-410.
Bard, E., Hamelin, B., & Fairbanks, R.G.
1990. 'U-Th ages obtained by mass spectrometry in corals from Barbados: sea level during the past 130,00 years' in Nature 346: 456-458.
Bischoff, J.L., N. Soler, J. Maroto and R. Julia.
1989. 'Abrupt Mousterian/Aurignacian boundary at c.40 ka bp: accelerator 14C dates from L'Arbreda cave (Catalunya, Spain)', JAS, 16: 563-76.
Blackwell, B. and H.P. Schwarz
1986. 'U-series analysis of the lower travertine at Ehringsdorf, DDR', QR, 25: 215-22.
Bowman, S.G.E. et al
1982. 'Preliminary dates for Pech de l'Azй IV' in Pact 6: 362-369.
Bowman, S.G.E. & Sieveking, G. de G.
1983. 'Thermoluminescence dating of burnt flint from Combe Grenal' in Pact, 9: 253-268.
Cabrera Valdйs, V & Bischoff, J.L.
1989. 'Accelerator 14C dates for early Upper Palaeolithic (basal Aurignacian) at El Castillo Cave (Spain in JAS, 16: 577-584.
Grьn R., Mellars, P. & Laville, H.
1991. 'ESR chronology of a 100,000-year archaeological sequence at Pech de l'Azй II, France' in ANT, 65: 544-551.
1988. 'Recent developments on the chronostratigraphy of the Paleolithic in the Pйrigord' in Upper Pleistocene Prehistory of Western Eurasia (Eds. H. Dibble & A. Montet-White). Philadelphia: University of Pennsylvania, University Museum Monographs No. 54, pp. 147-160.
Martinson, D.C. et al
1987. 'Age dating and the orbital theory of the ice ages: development of a high-resolution 0 to 300,000-year chronostratigraphy' in QR, 27: 1-29.
1986a. 'A new chronology for the French Mousterian period' in Nature, 322: 410-411.
1986b. 'Dating and correlating the French Mousterian': reply in Nature, 324: 113-114.
1988. 'The chronology of the south-west French Mousterian: a review of the current debate. In: L'Homme de Nйandertal, Vol. 4: La Technique (ed M. Otte). Liиge: Etudes et Recherches Archйologiques de l'Universitй de Liиge, pp. 97-120.
1989. 'Comment on radiocarbon accelerator dating of Roc de Combe samples' in ACM, 32: 101-102.
Mellars, P.A. & Grьn, R.
1991. 'A comparison of the electron spin resonance and thermoluminescence dating methods: the results of ESR dating at Le Moustier (France)' in CAJ, 1: 269-276.
Mellars, P.A. Trixier, J.
1989. 'Radiocarbon-accelerator dating of Ksar 'Aqil (Lebanon) and the chronology of the Upper Paleolithis sequence in the Middle East' in ANT, 63: 761-768.
Mellars, P.A. et al
1987. 'Radiocarbon accelerator dating of French Upper Paleolithic sites' in CA, 28: 128-133.
Mercier, N., Valladas, H., Joron, J.-L., Reyss, J.-L., Lйvкque, F. & Vandermeersch, B.
1991. 'Thermoluminescence dating of the late Neanderthal remains from Saint-Cйsaire' in Nature, 351: 737-739.
Parks, D.A. & Rendell, H.M.
1992. 'Thermoluminescence dating and geochemistry of loessic depostis in southeast England' in Journal of Quaternary Science, 7: 99-107.
Stoneking, M. et al
1992. 'New approaches to dating suggest a recent age for the human DNA ancestor', in The Origin of Modern Huamns and the Impact of Chronometric Dating (eds. M.J. Aitken, C.B. Stringer & P.A. Mellars). London: royal Society (Philosophical Transactions of the Royal Society, series B, 337, no. 1280), pp. 167-176.
1983. 'Some further notes on the morphology and dating of the Petralona hominid', JHE, V.12: 731-42.
1988. 'The dates of Eden', NAT, V. 331: 565-66.
Stringer, C.B. et al.
1989. 'ESR dates for the hominid burial site of Es Skhul in Israel', NAT, V. 338: 756-58.
Valladas, H. et al.
1986. Thermoluminescence dating of Le Moustier (Dordogne, France)', in Nature, 322: 452-454.
1988. 'Thermoluminescence dating of Mousterian "Proto-Cro-Magnon" remains from Israel and the origin of modern man', NAT, V. 331: 614-16.
Van der Hammen, T., Maarleveld, G.C., Vogel, J.C.
1967. 'Stratigraphy, climatic succession and radiocarbon dating of the last glacial of the Netherlands', in Geologie en Mijnbouw, 46: 79-95.
1990. 'A review of current research on TL dating of loess', QSR, 9: 385-397.
Wintle, A.G., Shackleton, N.J. & Lautridou, J.P.
1984. 'Thermoluminescence dating of periods of loess deposition and soil formation in Normandy', in Nature, 310: 491-493.
Woillard, G.M. & Mook, W.G.
1982. 'Carbon-14 dates at Grande Pile: correlation of land and sea chronologies', in Science, 215:159-161.
1978. 'Grande Pile peat bog: a continuous pollen record for the last 140,000 years', in QR, 9: 1-21.
1961. 'Vegetation, climate and radiocarbon datings in the Late Pleistocene of the Netherlands. Part I: Eemian and Early Weichselian' in Mededelingen Geologisches Stichting (New Series) 4: 15-45.
1995. Hominine preadaptations for language and cognition.Х In: Modelling the Early Human Mind (eds P. Mellars & K. Gibson). Cambridge: Mcdonald Institue for Archaeological Research.
Aeillo, L.C. & Dunbar, R.I.M.
1993. Neocortex size, groups size and the evolution of language. Current Anthropology, 34: 184-193.
1989. The evolution of the human psyche.Х In: The Human Revolution: behavioural and biological perspectives on the origins of modern humans. (eds P. Mellars & C. Stringer). Princeton: Princeton University Press, pp. 455-513.
1992. Palaeoart and archaeological myths.Х Cambridge Archaeological Journal 2: 27-57., 34: 184-193.
1981. The Roots of Language Ann Arbor: Karoma.
1990. Language & Species. Chicago: University of Chicago Press.
Bryne, R. W.
1995. Relating brain size to intelligence in primates.Х In: Modelling the Early Human Mind (eds P. Mellars & K. Gibson). Cambridge: McDonald Institute for Archaeological Research.