We have now published a study of the endocranial morphology of Maba, a Chinese fossil specimen dated approximately to the end of the Middle Pleistocene. The available portions of the upper face strongly resemble European Neandertals, like Saccopastore 1, found in Italy and supposed to have the same chronology of Maba, or Krapina 3, from Croatia. Also the spatial arrangement and the structural organization between face and braincase in Maba is reminescent of Neandertals. However, the frontal and parietal bones suggest an archaic endocranial morphology, more comparable with Homo heidelbergensis. So we have here an archaic brain form assembled onto a derived facial block. A similar situation (Neandertal traits in the face and archaic features in the vault) was also described for the sample from Sima de los Huesos (Atapuerca, Spain). If such affinity is a matter of phylogeny, the range of the paleospecies H. heidelbergensis – H. neanderthalensis should be revised, and extended to China. Otherwise, the facial Neandertal traits in this Chinese populations can be but a consequence of parallelism and analogy, and the specimen can therefore represent an archaic Asian taxon. Curiously, at the same time in Africa we have the opposite combination: Jebel Irhoud, a modern face with a Neandertal braincase! Definitely puzzling …
Posts Tagged 'frontal bone'
Tags: Atapuerca, China, frontal bone, Homo heildelbergensis, Krapina, parietal bone, Saccopastore
Tags: frontal bone, human genus, Sheela Athreya
Modern humans are supposed to have a bulging frontal squama, but little quantitative evidence is available on this topic. Most analyses included the browridge, the rest of the vault, or the whole skull, possibly confounding factors associated with the spatial relationships of the frontal bone with the other cranial elements. After the analyses of the frontal width and of the parietal curve in the human genus, here’s a quantitative approach to the curvature of the frontal squama (Am J Phys Anthropol 2013). Modern humans do actually have a more bulging frontal bone, independently upon orientation or position of the squama. Nonetheless, there is some overlapping between modern and extinct variation, suggesting caution when dealing with single specimens. Early modern humans display the same degree of frontal curvature than living modern humans.
See also this recent paper:
Athreya S. 2013. The frontal bone in the genus Homo: a survey of functional and phylogenetic sources of variation. J. Anthropol. Sci. 90:59-80. [pdf]