December 30, 2010

Study of Apidima 2 skull from Mani peninsula

Apidima 2 on the left, Petralona on the right. Apidima is a cave from southern-most Peloponnese, while Petralona is in northern Greece.

On the basis of the available evidence, the authors constrain the age of the skull between 115-105ka. They estimate his cranial capacity at 1,454cc, and note his very narrow face and high orbits.

Comparative analysis with H. sapiens, H. neandertalensis, H. heidelbergensis skulls suggests that the skull has Neandertal affinities. Below is the canonical variates analysis:

Apidima 2 is within the enclosing polygon of Neandertal specimens, being quite close to Guattari from neighboring Italy. It is also striking how close Petralona and Sima de los Huesos (attributed to H. heidelbergensis) are in this analysis, with La Ferassie 1 being particularly close to them.

Of particular interest is the position of Broke Hill (Kabwe/Rhodesian Man). Its relationship with European heidelbergensis is evident in its position along CV1, but I don't see how an especially close relationship with H. sapiens can be inferred. This seems consistent with the finding of H. sapiens beign separated from the heidelbergensis-neanderthalensis lineage, as well as the gist of a recent Tattersall paper which found it difficult to link modern Homo sapiens's derived morphological description to specimens usually called "archaic Homo sapiens". Kabwe is sometimes noted as an archaic H. sapiens representing an intermediate stage in the lineage that culminated in Omo and Herto.

The variability in the Skhul/Qafzeh specimens is also evident: Skhul 5 deviates strongly towards Neandertals/heidelbergensis while Qafzeh 6 is right in the middle of H. sapiens and Qafzeh 9 is intermediate. My own MCLUST analysis has Qafzeh 6 in the Australoid cluster while Skhul 5 is placed in the Neandertal cluster. This seems consistent with this CV analysis.

All in all, the authors of the current paper note the Neandertal affinities of Apidima 2, while noting that:
Contrary to our expectations, Apidima 2 did not show affinities with H. heidelbergensis (s.l.) or with the Petralona cranium in particular, but aligned more closely with our Neanderthal sample despite having been grouped a priori with H. heidelbergensis (s.l.). A brief comparison of the Apidima 2 frontal view to that of Petralona (Fig. 2) confirms several differences between the two specimens, including a more Neanderthal-like, relatively narrower face and higher cranium in Apidima (although the exact position and orientation of the two specimens could not be controlled and is not identical). However, Apidima 2 appears to lack the extremely derived Neanderthal nasal morphology, including the very high and protruding nasal bridge.

Journal of Human Evolution (in press)

Multivariate analysis and classification of the Apidima 2 cranium from Mani, Southern Greece

Katerina Harvati, Chris Stringer, Panagiotis Karkanas



Andrew Oh-Willeke said...

The chart certainly does make a case for Petralona, Sima de los Huesos, La Ferassie 1 and Skhul 5 all forming one cluster that is part of the same line of evolution as the Neanderthal cluster (perhaps with this group and the other Neanderthal cluster forming two subspecies); and for Kabwe to be the only true separate species from Neanderthal in the archaic group; while putting Qafzeh 6 and Qafzeh 9 in the Upper Paleolithic modern human group.

Skhul 5 is really the most striking outlier in the chart. This is well outside the Upper Paleolithic modern human range on both CV1 and CV2 in the chart, is very close to Kabwe in CV1 and is very close to Petralona and Sima de los Huesos and CV2 (in addition to not being too far on CV1).

If Skhul 5 is not Neanderthal or H. heidelbergensis, it must surely be at least a hybrid individual.

T. Kosmatka said...

Yes, certainly interesting that Skhul 5 sits like a bulls-eye between the three groups.