New Data on Neandertal Anatomy

Anatomists have reconstructed the rib cage of the Kebara 2 Neandertal to get a better understanding of the trunk of our nearest relatives.  Science Daily has the story:

An international team of scientists has completed the first 3D virtual reconstruction of the ribcage of the most complete Neanderthal skeleton unearthed to date, potentially shedding new light on how this ancient human moved and breathed.

The team, which included researchers from universities in Spain, Israel, and the United States, including the University of Washington, focused on the thorax — the area of the body containing the rib cage and upper spine, which forms a cavity to house the heart and lungs.

What did they find?

The reconstruction of the thorax, coupled with the team’s earlier finding, shows ribs that connect to the spine in an inward direction, forcing the chest cavity outward and allowing the spine to tilt slightly back, with little of the lumbar curve that is part of the modern human skeletal structure. “The differences between a Neanderthal and modern human thorax are striking,” said Markus Bastir, senior research scientist at the Laboratory of Virtual Anthropology at the National Museum of Natural History in Spain.

“The Neanderthal spine is located more inside the thorax, which provides more stability,” said Gomez-Olivencia. “Also, the thorax is wider in its lower part.” This shape of the rib cage suggests a larger diaphragm and thus, greater lung capacity.

In my anthropology class, I teach about the effects of Bergmann’s and Allen’s rules of body morphology. In the case of Neandertals, the adaptations to the cold were shortened distal limb segments, a large, projecting mid-face and a tendency toward barrel-chestedness. The new study reinforces these ideas.

Interestingly, it should be noted that the Kebara Neandertal is found in Israel, not known for its cold climate.  It is hypothesized that the Neandertal population came down from Eastern Europe to escape the cold (the tundra line was at Vienna).  What is peculiar about the Kebara 2 Neandertal is that it consists only of a body.  Whether he died and his head fell in a stream or some animal carried it off, there is no cranium.  Oddly, what we do have is one of the bones that is preserved least in the fossil record: a hyoid.  It is this that has given us the most information about the Neandertal vocal tract.

Fun stuff.