Discuss evolution reading group

Trinkaus and Neandertal difference

Introduction by John Wilkins: This paper garnered a lot of media interest, but most of it was wrongly phrased (in terms of "genetics", not morphology). This paper asks the question whether modern humans are more derived than Neandertals and if we have over-focussed on Neandertal "deviation" from the "evolutionary norm". It raises what I think are some basic questions about the nature of phylogenetic classification and the role of morphology in evolutionary investigations. The paper is relatively short if you do not spend much time on the tables, and there are a number of useful critical comments by others at the end.

Abstract: Considerations of morphological variation among later Pleistocene human groups have focused principally on the distinctiveness of the Neandertals of western Eurasia relative to their predecessors and to penecontemporaneous and recent modern humans. In this discussion, there has been a dearth of attention of the degree to which modern humans are derived relative to earlier members of the genus Homo. Of 75 cranial, mandibular, dental, axial, and appendicular traits in which the Neandertals and/or modern humans are derived relative to Early and Middle Pleistocene Homo, approximately one-quarter are shared among Neandertals and modern humans, a similar percentage largely unique to the Neandertals, and about half largely unique to modern humans. The results are similar whether the Neandertals are compared with the earliest modern humans or with their Late Pleistocene and more recent modern human successors. Even though these figures could shift modestly through variation in trait selection and/or as a result of a more complete earlier Pleistocene Homo fossil record, it is apparent that modern humans are morphologically more derived than the Neandertals. Our focus should therefore be at least as much on the evolutionary biology of early and recent modern humans as on that of the Neandertals.

The paper can be downloaded from here.

posted by John S. Wilkins @ 1:44 PM