January 16, 2007

New study on Pestera cu Oase cranium from Romania

I don't see the study online yet [it is now online, see below], but here is the EurekAlert release:
Putting a face on the earliest modern Europeans

The earliest modern humans in Europe were not completely "modern" and continued to evolve after they settled on the continent nearly 40,000 years ago, according to new research published this week in the Proceedings of the National Academy of Sciences (PNAS).

An international team of researchers, including Hélene Rougier, Ph.D., post-doctoral fellow, and Erik Trinkaus, Ph.D., professor of anthropology, at Washington University in St. Louis, has been studying a 35,000-year-old cranium discovered in the Pestera cu Oase, in western Romania. The fossil specimen is the earliest largely complete example of an early modern human skull known from Europe.

The modern humans emerged within eastern Africa some 150,000 years ago, spread temporarily into extreme southwest Asia and into southern Africa, and then through northern Africa into Europe around 40,000 years ago. This skull is from the first 5,000 years of the apparent occupation of Europe by modern humans.

The cranium has no expressly Neandertal traits, those of its immediate predecessors in Europe. Yet, its combination of modern and archaic features can be used to reinforce arguments for some degree of mixture of Neandertals and modern humans, inferences that have been made from other early modern European fossils. In addition to its large face and retreating forehead, it has the largest cheek teeth so far known for an otherwise anatomically modern human.

But Rougier and Trinkaus have emphasized that the Oase 2 cranium is particularly important in showing that the earliest modern humans in Europe were not completely "modern." "I think that what this find really shows is the ongoing nature of human evolution," said Trinkaus. "Technically, this skull is a modern human, but humans as we know them today have evolved considerably since then."
Proc. Natl. Acad. Sci. USA, 10.1073/pnas.0610538104

Pestera cu Oase 2 and the cranial morphology of early modern Europeans

Hélène Rougier et al.

Between 2003 and 2005, the Pestera cu Oase, Romania yielded a largely complete early modern human cranium, Oase 2, scattered on the surface of a Late Pleistocene hydraulically displaced bone bed containing principally the remains of Ursus spelaeus. Multiple lines of evidence indicate an age of {approx}40.5 thousand calendar years before the present ({approx}35 ka 14C B.P.). Morphological comparison of the adolescent Oase 2 cranium to relevant Late Pleistocene human samples documents a suite of derived modern human and/or non-Neandertal features, including absence of a supraorbital torus, subrectangular orbits, prominent canine fossae, narrow nasal aperture, level nasal floor, angled and anteriorly oriented zygomatic bones, a high neurocranium with prominent parietal bosses and marked sagittal parietal curvature, superiorly positioned temporal zygomatic root, vertical auditory porous, laterally bulbous mastoid processes, superiorly positioned posterior semicircular canal, absence of a nuchal torus and a suprainiac fossa, and a small occipital bun. However, these features are associated with an exceptionally flat frontal arc, a moderately large juxtamastoid eminence, extremely large molars that become progressively larger distally, complex occlusal morphology of the upper third molar, and relatively anteriorly positioned zygomatic arches. Moreover, the featureless occipital region and small mastoid process are at variance with the large facial skeleton and dentition. This unusual mosaic in Oase 2, some of which is paralleled in the Oase 1 mandible, indicates both complex population dynamics as modern humans dispersed into Europe and significant ongoing human evolution once modern humans were established within Europe.


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