All history contains lessons about our own humanity, but these are often couched in ambiguous terms. The same is true for the saga of the Neanderthals in Europe and the Middle East (Figure 20.4), over a time (perhaps between 30,000 and 100,000 years) when this interesting species crossed paths with anatom- ically modern humans.
20.7.1 Climate setting
The first hints of characteristic Neanderthal features and tools extends back 300,000 years ago or so, in Europe and west- ern Asia. The last physical evidence for Neanderthals is found in southern Spain as recently as 27,000 years ago. This long interval spans two major glacial episodes of the Pleistocene, as seen in the oxygen-isotopic record from sea sediment cores, dis- played in Figure 20.5. Separating the two is Earth’s penultimate interglacial (we are living in the most recent one), extending from 118,000 to 126,000 years ago. During the interglacial time, forests would have covered large areas of continents, includ- ing Europe and Asia. A variety of large mammals seen today in restricted regions were present throughout the world; hip- popotami and elephants were found in the British Isles, for example.
More recently than 118,000 years ago, temperatures initiate a somewhat bouncy descent toward the most recent glacial, though they do not begin to approach the cold of the previous glacial until 70,000 to 80,000 years ago. In the range of the Nean- derthals, broken woodlands existed, probably supporting herds of grazing animals; many of the large mammals disappeared as the glaciation intensified.
From 70,000 to 30,000 years ago, ice sheets advanced and retreated in rapid oscillations. Major cold episodes (such as 60,000 to 70,000 years ago) must have accelerated extinctions of a variety of animals; forests retreated southward and previous woodlands likely became open tundra in Europe. In the Mid- dle East, periods of clement climate may have existed at these colder times, encouraging migration of Neanderthals down to that geographic crossroad of the world. The final mild climate
Feldhofer Cave
Kiik-Koba
Teshik Tash
Amud & Zuttiyeh Kebara Skhul & Tabun La Borde
Pech-de-l’Aze Regourdou St. Cesaire
La Quina La Micoque
FRANCE
La Chapelle- aux-Saints Spy
Krapina ALPS
Late Pleistocene glacial maximum
Middle Pleistocene
glacial maximum
Neanderthal B oundary Feldhofer Cave
Kiik-Koba
Teshik Tash
Amud & Zuttiyeh Kebara Skhul & Tabun La Borde
Pech-de-l’Aze Regourdou St Cesaire
La Quina La Micoque
FRANCE
La Chapelle- aux-Saints
Krapina ALPS
Late Pleistocene glacial maximum
Middle Pleistocene
glacial maximum
Neanderthal B oundary Feldhofer Cave
Kiik-Koba
Teshik Tash
Amud & Zuttiyeh Kebara Skhul & Tabun La Borde
Pech-de-l’Aze Regourdou St Cesaire
La Quina La Micoque
FRANCE
La Chapelle- aux-Saints
Krapina ALPS
Late Pleistocene glacial maximum
Middle Pleistocene
glacial maximum
Neanderthal B oundary Feldhofer cave
Kiik-Koba
Teshik Tash
Amud & Zuttiyeh Kebara Skhul & Tabun La Borde
Pech-de-l’Aze Regourdou La Quina
La Micoque FRANCE
La Chapelle- aux-Saints
Krapina
glacial maximum
middle Pleistocene
glacial maximum
Neanderthal oundary Kiik-Koba
Teshik Tash
Amud & Zuttiyeh Kebara Skhul & Tabun La Borde
Pech-de-l’Aze Regourdou La Quina
La Micoque FRANCE
La Chapelle- aux-Saints
Krapina
Neanderthal oundary Neanderthal burial sites Neanderthal burial sites Neanderthal burial sites Neanderthal burial sites Neanderthal burial sites Neanderthal burial sites
Kiik-Koba
Teshik Tash
Amud & Zuttiyeh Kebara Skhul & Tabun La Borde
Pech-de-l’Aze Regourdou St. Cesaire
La Quina La Micoque
FRANCE
La Chapelle- aux-Saints Spy
Krapina ALPS
late Pleistocene
Neanderthal boundary
Figure 20.4General geographic areas occupied by Neanderthals. Dashed lines indicate the extent of the glaciers during the middle and late Pleistocene. Modified from original figure by Annick Peterson from Stringer and Gamble (1993) by permission of Thames and Hudson.
18O 9 8 7 6 5 4 3 2 1
e d c b a
high
low sea level
303,000 245,000 186,000 128,000
Years before present
71,000 59,000 24,000 13,000
Figure 20.5Sea level, and hence temperature, over the past 300,000 years from oxygen-18 data in seafloor sediments (see Chapter 6 for discussion of technique). Times of high sea level, hence less ice, are warm; low sea level indicates colder, glacial epochs. The numbers from 1 to 9 are standard labels for glacial and interglacial episodes. From Stringer and Gamble (1993) by permission of Thames and Hudson.
episode before the peak of the last glaciation occurred 40,000 years ago. The climactic freeze was reached about 19,000 years ago, after the extinction of the Neanderthals.
Early Neanderthals, with somewhat different features than their “late” Neanderthal descendants, existed from perhaps 300,000 to 130,000 years ago. The time after that, up to perhaps 40,000 years ago, was really the heyday of the Neanderthals, with characteristic stone cultures and stable physical features.
During this time, Neanderthals made incursions into the Middle East, interleaving with peoples of more modern appearance and stone cultures. From 40,000 years to their extinction, the Nean- derthal populations declined in geographic distribution, while innovating through imitation of stone tool types brought by the modern peoples emigrating to Europe.
20.7.2 Physical features of Neanderthals
Neanderthals were not the stooped over, ape-like, brutish cousins of the depictions of the popular literature. They were short but very robust people, with broader and deeper muscle attachments in their bones, and hence more massive musculature, than the average for any modern populations. Although their hip attach- ments differ from ours in encouraging more stress on the sides of their thighs than on the front and back (making easier the squatting and sideways movements typical of foraging activity), the fossil remains of their skeletons are consistent with fully upright postures.
It is the head of Neanderthal people that most dramatically outlines the difference from all modern humans (Figure 20.6).
Figure 20.6The author as (left)Homo neanderthalensis; (right) Homo sapiens.
The Neanderthal skull has very heavily enlarged brow ridges; a cranial vault that is low and somewhat flattened relative to that of modern humans; more massive jaws and teeth relative to the rest of the skull than in modern humans; a huge, broad nose, and virtually no chin. However, the cranial capacity of Neanderthals equaled or exceeded that of modern humans. To accommodate the brain in the more flattened skull, Neanderthal heads had a more prominent rear “bun,” than do modern humans. Human skulls are constructed such that they grow outward as the brain grows during infancy and childhood. Presumably Neanderthal’s did the same, hence the shape of the skull, which would strike any human being today as being very odd, reflected a differently shaped (and presumably differently functioning) brain, but one on average somewhat larger than ours.
Many of the features of human and Neanderthal heads likely related to the need to support chewing and grinding forces.
Our skulls have high front domes, providing adequate support against muscular forces; Neanderthal brow ridges did the same in the absence of the high forehead. Our chins likewise provide structural support during chewing, and are a somewhat unusual innovation in the hominid line; Neanderthal jaw stresses were supported by more traditional heavy bones.
The striking stockiness of Neanderthal bodies (both male and female) and evidence for large muscles could readily be argued as a result of a more strenuous physical lifestyle. However, such features are present in preadolescent Neanderthal children, whose ages at death are easily dated from the state of their den- tition. The stocky build surely enabled a physically demanding lifestyle, but may have had its origin in adaptation to the very cold climate that characterized Europe during much of the Nean- derthal heyday. This is the case among modern people who live in very cold climates – but not nearly as extreme as that of the Neanderthals.
A further clue to this adaptation lay in the heroically sized nose. Anthropologists have argued that it could serve two possi- ble (and likely simultaneous) functions: warm the frigidly glacial air as it is inhaled, and allow for a greater volume of inhala- tion with a consequently higher tolerance for physical exertion.
Enthusiasts for backcountry winter sports know the hazards of overexertion and consequent sweating: hypothermia (a loss of body temperature control) and death can result. A bigger nose is an adaptation allowing a high-exertion lifestyle in the cold.
Having emphasized the differences from modern humans, it is now necessary to remark upon how close the Neanderthals are to us in their appearance. Meet one in modern dress in an office and you would do a double-take: this seems to be a human being, but what a strange head and face! More dif- ferent than any of the remarkable variety we share as mod- ern humans, one of the great enigmas of the Neanderthals is the juxtaposition of the oddness with the closeness to modern humans. Most anthropologists today hold the view that Nean- derthals areHomo neanderthalensis, a different species sharing the same genus as modern humans. The physiological differ- ences between Neanderthals and modern humans are larger than between other primates that are, without controversy, classified as different species.
The origin of Neanderthals seems to lie in pre-existing popu- lations ofHomo erectusor a successor speciesHomo heidelber- gensis, resident in Europe as well as western Asia for many hun- dreds of thousands of years. Many of the traits of Neanderthal features can be seen in fossils from prior to 300,000 years ago in England, Germany, Greece, and France – remains that seem transitional between erectus/heidelbergensisand Neanderthal.
Far removed from the changes occurring in Africa that led to modern Homo sapiens, the Neanderthals were an evolution- ary event in and of themselves – a distinct population ofHomo evolved from ancestors who migrated out of Africa or Asia long before the speciation event that produced modernHomo sapiens.
Neanderthal fossil remains show differences from individual to individual. However, these differences are smaller than are the differences between individual members of today’s modern humans. Our species has spanned the globe, adapting to a range of climates far greater than those the Neanderthals contended with. It is not surprising, then, that we should be a more varied species than Neanderthal. Equally important is the lack of tran- sitions between Neanderthals and modern humans. With only a few controversial exceptions from the Middle East, the fossil record seems to be telling us that there is no transitional form, no people that reflect a strong heritage of interbreeding between coexisting Neanderthals and modern (or near-modern) humans who lived at the same time.
Beginning in 1997, extraction and analysis of DNA samples from Neanderthal bones has been possible. In 2010, scientists announced that the Neanderthal genome had been sequenced.
The Neanderthal genome is about the same size as the human genome, and is identical to ours to a level of 99.7% (this is comparing the ordering of the lettering in the nucleotide bases).
Using an average rate of mutations, Neanderthal and human lineages diverged between 270,000 and 440,000 years ago – well before modern humans arose. This is consistent with the indications from the fossil record of the break being at least 300,000 years ago, since older Neanderthal-like fossils may still lie undiscovered, and the mitochondrial mutation rate, or “clock”
is likely uncertain by a factor of at least two. Indications that the modern individuals of European and Asian stock share more of the Neanderthal genome than do modern Africans indicates that some amount of interbreeding occurred between modern humans and Neanderthal after modern humans had migrated out of Africa. However, analysis of these genes suggest the interbreeding occurred before modern humans entered Europe and the more distant parts of Asia. Once moderns had found
their way well into Asia and Europe, the story ofHomo nean- derthalensis remains a largely separate one from our species, played out on the same stage at the same time.
20.7.3 Neanderthal lifestyle
Neanderthal cultures have been exaggerated in the popular liter- ature in both directions – emphasizing the primitive and exag- gerating their abilities. Neanderthals buried their dead, but the extent to which the burials were ceremonial remains in dispute.
(The arrangement of artifacts and animal bones is not much removed from accidental, in most cases.) They left no cave paintings, unlike the prolific European artists, Cro-Magnons, who replaced them, but the Neanderthals did leave evidence that they used pigments for some purposes. They had distinctive tool styles, yet variety and innovation are extremely limited: Nean- derthal tool types remain similar for blindingly long expanses of time (tens of thousands of years). The sophistication of the tools, compared to those of Cro-Magnon, is low and would have provided relatively limited assistance in a physically demanding environment.
In some cases, a handful of different tool styles will be seen in a limited area (about 100 km in extent) for thousands of years.
This, combined with other evidence that Neanderthal population densities were always very low compared with that of modern humans, suggests that Neanderthal populations didn’t interact with each other. Groups would come and go across a landscape, rarely or never encountering each other. This is very different from all modern human cultures; modern humans are a traveling species characterized by the continual interaction of different tribes, cultures, and nations.
Part of the reason for such noninteraction may be that Nean- derthal groups ranged over very limited areas. Analysis of tools and animal remains suggests that hunting occurred, but not with the reliance on sophisticated tools constructed by even early tribes of modern humans. The extent of skeletal injuries among Neanderthal finds suggest that hunting may have been a very physical and brutal affair: cooperative certainly, but low tech.
Foods gathered and scavenged were likely important compo- nents of their diet as well.
Details of Neanderthal social life are at best sketchy; at worst, fictional. The anatomy of the skull and neck area suggest that Neanderthals could not be as articulate as modern humans;
whether that meant that speech was not heavily employed is unclear. The arrangement of family groups is also speculative.
Some anthropologists argue that the characteristics of Nean- derthal hearths and other structures in caves imply a very differ- ent arrangement from most or all modern humans; in particular, one in which males lived separately from females in day-to- day existence. Other anthropologists argue that such inferences constitute overinterpretation.
At the heart of such musings lies the question of the Nean- derthal mind. Given that we do not understand well the nature of our own brain, speculations based on skull size and shape are dangerous ones. Undoubtedly there were differences in the behavior, capabilities, and skills of Neanderthals relative to mod- erns; unfortunately, the nature of those differences is so faintly hinted at by the physical evidence that they remain wholly mysterious.
20.7.4 Interaction of Neanderthals with moderns Neanderthals and moderns overlapped in geographic range for almost a third the duration of Neanderthal’s existence. Modern forms ofHomo sapiensmoved into the Middle East from Africa by about 90,000 years ago. Neanderthal, under pressure dur- ing especially cold periods to move south, is found as early as 120,000 years ago and as recently as about 50,000 years ago in the Middle East.
As modern humans pushed outward from Africa, they began to appear in Europe by about 45,000 years ago, spurred on perhaps by episodes of unusual warmth around that time.
Unlike the Middle East, a geographic crossroads from which both species came and went, Europe is a continental cul-de- sac. As moderns spread across Europe, bringing sophisticated tools and weaponry, efficient hunting techniques, and a lifestyle that included much contact and interchange between tribes, the Neanderthals began to be pressured. It would take almost 20 millennia for the Neanderthals to succumb; at any given time it might well have looked like the two species were coexisting peacefully.
A sign of the pressure on Neanderthals is a change in their monotonous stone tool culture. Later tool sets associated with Neanderthals show much more variety than do their earlier clas- sic tool types, and a resemblance to the kind of tool kits the moderns were using. Whether Neanderthal tried to imitate the moderns to gain the latter’s hunting advantage, or for other rea- sons, the change in tool types occurs only after modern-type humans arrived in Europe.
From 40,000 to 27,000 years ago, the geographic range of Neanderthals shrinks progressively, ending in southern Spain.
This area is geographically distant from natural migration routes, and represents a logical “last refuge” for a people who are suc- cumbing to whatever pressures the moderns were bringing to bear. Extinction need not have been caused by war or other direct suppression. Only a very small reduction in breeding suc- cess is required to eventually drive a species to extinction. For a typical human generational interval (20–30 years), a roughly 2% difference in successful child-rearing between Neanderthals and moderns could have led to Neanderthal extinction in a mil- lennium.
The moderns who first migrated to Europe and, by their advanced hunting techniques and gregarious lifestyles, drove Neanderthal to extinction, were not the Europeans of today.
They were Cro-Magnon, a tall and slender race that does not resemble any of the modern peoples of Europe. They were, however, anatomically modern in essentially all respects, and the differences in features from today’s Europeans is racial in nature. Successive migrations to Europe over the millen- nia brought other peoples to Europe; it is possible to trace many such waves just as one can for other parts of the world.
The most ancient Europeans living today are thought to be the Basque people, both on linguistic grounds and through analysis of mitochondrial DNA. Well before them, however, came Cro- Magnon and others who have left their legacy in cave paint- ings, animal sculptures, musical instruments, elaborate buri- als, advanced tool kits, evidence of highly organized settle- ments, and perhaps a genetic contribution to later peoples of Europe.
20.7.5 Who were the Neanderthals?
The bulk of the anthropological evidence indicates that Nean- derthals were a separate species of humans that evolved more or less in place from earliererectus, or closely related, species.
This evolution occurred during a time when various other archaic populations, less well understood from the fossil record, arose fromerectus-type populations in Africa, Asia, and possibly Aus- tralia. The Neanderthal speciation resulted in a people who had a cranial capacity similar to or larger than modern humans, but with significantly different physical and cultural attributes, reflecting perhaps substantial behavioral and intellectual differ- ences as well. Displaced by modern humans who originated much later than they did, the Neanderthals are considered to be a separate and older natural experiment in the speciation of human beings, one that lived a long time and nearly made it to the present day.
The focus here on the Neanderthal story is not meant to imply that it is the most important episode in human evolution. It is, instead, the best documented of the interactions between archaic human populations – those derived from the ancientHomo erec- tusmigrations out of Africa – and moderns, those peoples result- ing from the much later speciation event in Africa that produced modernHomo sapiens. The replacement of archaics by moderns occurred elsewhere around the world (excepting the Americas and Antarctica, where archaics were absent), but nowhere else is the physical evidence so extensive and clear.
We yearn to meet ancestors who will tell us where we came from and why – we people our myths with giants and elves, ogres and trolls, beings who are not quite human, and whose imagined existence allows us to hold a mirror up to ourselves, to evaluate what it truly means to be human. The occasional encounter of modern humans with Neanderthals between 45,000 and 27,000 years ago might have carried with it some of that mythic quality, a reckoning with another intelligent species whose common origin in the distant past could have been intu- ited by both species but not understood. Those of us alive today missed the chance for such an encounter by no more than a quarter of the span of time of modern humans, and less than 2%
of the Pleistocene epoch.