Neandertal interaction with Cro-Magnons

Neanderthals apparently co-existed with anatomically modern humans beginning some 100,000 years ago. However, about 45,000 years ago, at about the time that stoneworking techniques similar to those of Cro-Magnon people appeared in Europe, Neanderthals began to be displaced. Despite this, populations of Neanderthals held on for thousands of years in regional pockets such as modern-day Croatia and the Iberian and Crimean peninsulas. Cro-Magnon are considered by most authorities to have been behaviorally modern Homo sapiens; they were certainly anatomically modern.

There is considerable debate about whether Cro-Magnon people accelerated the demise of the Neanderthals. Timing suggests that the developing behavior patterns of Cro-Magnon may have had considerable impact on the process. Jared Diamond has compared the likely interaction between Cro-Magnon people and Neanderthals to the genocides suffered by indigenous peoples in recent human history. However, other authors have pointed out that even a slight selective advantage on the part of modern humans could account for Neanderthals' replacement on a timescale short compared with the resolution of the archaeological record, even in the absence of violent physical conflict or an asymmetry of susceptibility to pathogens. Neanderthals were stout and extraordinarily powerful, with cranial capacities as large or larger than Cro-Magnons. Nevertheless one school of thought holds that they were outcompeted by Cro-Magnons because they lacked complex language and therefore the ability to pass on more than rudimentary knowledge to their descendants.¹

In some areas of the Middle East and the Iberian peninsula, Neanderthals did, in fact, co-exist side by side with populations of anatomically modern Homo sapiens for roughly 10,000 years. There is also evidence that it is in these areas where the last of the Neanderthals died out and that during this period the last remnants of this species had begun to adopt — or perhaps independently innovate — some aspects of the Châtelperronian (upper paleolithic) tool case, which is usually exclusively associated with anatomically modern Homo sapiens.

Skeletons apparently sharing Neanderthal and Cro-magnon features have been found in Portugal; it is unclear whether these are in fact hybrids of the two species, or simply extreme individuals of one or the other species. These may suggest the two species did interbreed. However, it has been speculated that these hybrid individuals could have been sterile. It is very difficult to prove as the genetic differences between Neanderthals and Cro-magnons were far more minute than the morphological differences between the two species might seem to indicate. Tests comparing Neanderthal and modern human mitochondrial DNA show too great a dissimilarity for Neanderthals to have contributed to the human mitochondrial genome. The mtDNA indicated a split between Homo sapiens and Neanderthals occurred more than 500,000 years ago. Morphological symmetry and asymmetry often belies genetic truth in the case of these ancient Homo populations. In any case it is possible but highly unlikely that the Neanderthals, with their small sedentary populations, could have been absorbed by the much larger populations of modern Homo sapiens, but without living Neanderthals it cannot be absolutely proven that they could interbreed with anatomically modern Homo sapiens to produce viable offspring. These hybrid remains should not be confused with Homo heidelbergensis, the more ancient common ancestor of both the Neanderthal and modern man.

Although Dr. Jared Diamond and others have specifically mentioned Cro-Magnon diseases as a threat to Neanderthals, this aspect of the analogy with the contacts between colonisers and indigenous peoples in recent history can be misleading. The distinction arises because Cro-Magnons and Neanderthals are both believed to have lived in a way we would now call nomadic, whereas in those genocides of the colonial era in which differential disease susceptibility was most significant, it resulted from the contact between colonists with a long history of agriculture and nomadic hunter-gatherer peoples. Diamond argues that asymmetry in susceptibility to pathogens is a consequence of the difference in lifestyle, which makes it irrelevant in the context of the analogy in which he invokes it.

Both the Neanderthals' place in the human family tree and their relation to modern Europeans has been hotly debated ever since their discovery. They have been classified as a separate species (Homo neanderthalensis) and as a subspecies of Homo sapiens (Homo sapiens neanderthalensis) at different times. The consensus has been, based on ongoing DNA research, that they were a separate branch of the genus Homo, and that modern humans are not descended from them (fitting with the single-origin hypothesis). Some recent genetic research has pointed toward the possibility that the gene responsible for red-hair, freckles, and large noses in modern Europeans had Neanderthal origins (at least partially indicating support for a multiregion origin). In addition to the genetic research, the shapes of the Neanderthal and modern human skulls are significantly different, in ways that make it unlikely that Homo sapiens are descended from Neanderthals.

Dr Myra Shackley has speculated that a surviving population of Neanderthals may be the Almas: a wild man reported in the Caucasus and other regions. This view is generally regarded as speculative and highly unlikely.

Notes

1. The theory that Neanderthals lacked complex language was widespread until 1983, when a Neanderthal hyoid bone was found at the Kebara Cave in Israel. The bone that was found is virtually identical to that of modern humans. The hyoid is a small bone that holds the root of the tongue in place, and its presence seems to imply some ability to speak. Many people believe that even without the hyoid bone evidence, it is obvious that a tool case as advanced as the Mousterian Era, attributed to Neanderthals, could not have been developed without cognitive skills encompassing some form of spoken language.