A comparison of a modern human skull, left; a frontal skull fragment from Palau, center; and the Flores skull, right.
Photo credit: Stephen Alvarez/National Geographic

GW researchers recently presented new evidence to support the theory that the fossil species Homo floresiensis, known as the “Hobbit,” represents a unique human lineage that diverged from our own, possibly as long ago as 1.7 million years ago, and strikes another blow against the idea that human evolution occurred in a linear progression. The research appears in Proceedings of the National Academy of Sciences.

GW researchers Adam Gordon, Lisa Nevell, and Bernard Wood developed a novel way to compare the shape of the “Hobbit’s” skull with what the shape of modern human skulls would be like in individuals as small as the “Hobbit.” Using these new methods, they have shown that the “Hobbit’s” skull is shaped nothing like that of a modern human, whether or not size differences are taken into account. More information about the findings is available at the GW News Center.

Femur Fossils Provide the Clues to Human Ancestor's Bipedalism
Credits: (Artwork and Composite) John Gurche; (Photograph) Brian Richmond

Research published recently by another GW faculty member contributes to our knowledge about human evolution. GW Anthropology Professor Brian Richmond and Stony Brook University Professor William Jungers have discovered that humans’ early ancestors were adapted to walking upright on two legs almost six million years ago, settling scientific debate over fossils found in 2000. This finding shows that the fossils belong to very early human ancestors and that upright walking is one of the first human characteristics to appear in our lineage, just after the split between human and chimpanzee lineages.

The research is the first thorough analysis of the Orrorin tugenensis fossil – a fragmentary piece of femur (thigh bone) – which was discovered in Kenya in 2000 by a French research team. Until this analysis, scientists have engaged in debate over the fossil’s significance. The fossil’s age, almost six million years old, falls within the timeline (five to eight million years ago) of when genetic differences indicate that chimpanzees and humans had a common ancestor. The findings are published in the March 21 issue of the journal Science. More information about this research is available on the GW News Center.