Spatial abilities, cognition and the pattern of Neanderthal and modern human dispersals

Neanderthals and anatomically modern humans (AMHs) are very closely related, although their skeletal morphology is distinct enough for them to be classified as separate species. Their physical differences, including the architecture of the skull and post-cranial skeletal proportions, do not explain the extinction of the Neanderthals as a species, however. The post-cranial morphology of the Neanderthals, which is generally believed to reflect an active lifestyle under cold conditions, falls within the range of modern human variation. Their cranial capacities are essentially identical and skull morphology does not convey any obvious adaptive advantage to either species. The existence of other, less easily discernible biological traits that might have contributed to the extinction of the Neanderthals – such as differences in reproductive rates or developmental histories – cannot be ruled out, but are not supported by current data. Behaviourally (culturally) based explanations for the process of replacement of Neanderthal populations by AMHs center on archaeological evidence for more complex patterns of social organisation, associated with the use of symbols and the development of new technologies. This paper explores the link between social complexity, spatial distribution and cognition during the Late Pleistocene, suggesting a mechanism whereby cognitive differences between hominid species may have arisen.