Growing up Neandertal
They were not us. That is, Neandertals were probably not members of our own species, judging from recent analyses of mitochondrial DNA (described in the November-December 2003 issue). Nonetheless, Neandertals were clearly built on a human-like plan (or vice versa) with some crucial modifications.
A glance at the fossil remains of these hominids shows that Neandertal bones are much more robust than those of modern Homo sapiens. The skulls of the two species also show several striking differences. One of the most noticeable Neandertal features is the unmistakably large, bony browridges that stick out over the eyes. Below the orbits, the face is more prognathic—the nose and jaw protrude farther in front of the braincase—than a human face. The prominent nasal bones in Neandertal skulls top wide nasal openings, suggesting that they sported large, aquiline noses. Unlike the smoother, rounded contour of the human skull, the back of the Neandertal skull has a distinctive bulge, often referred to as a chignon or bun. Overall, the Neandertal skull resembles what you might expect if someone took a human skull made of rubber, grabbed it by the face and back of the head, and pulled.
These comparisons attracted the attention of scientists who study the interactions between evolution and development from birth to adulthood—so-called "evo-devo." Put simply, they wanted to know: How do you grow up Neandertal?