Although the cranium, or brain case, of early modern humans dating back 200,000 years isn't much larger than those today, it has a very different form, which suggests that the brain has evolved more rounded over time. The dominant theory holds that behavioral changes, such as the creation of tools and art, led to changes in the form of the Homo sapiens brain, which in turn affected the shape of the skull that protects it. However, there are numerous interrelated factors at work and little fossil evidence.

According to a new PLoS study

Then, 125 examples of contemporary humans were compared to the 3D models of the 50 fossils. The researchers were able to distinguish the function of the brain in the development of the skull by contrasting the brain cases of early modern human children and adults for the first time. While the size and dimensions of H. sapiens children's skulls from 160,000 years ago were broadly identical to children today, the team was astonished to find that the adults appeared radically different from modern adults, with significantly longer faces and more pronounced features.