
COLUMBIA, MISSOURI—The 1.9 million-year-old pelvis and femur fossils of an early human ancestor suggest that there was greater diversity in the human family tree than had been thought. “They differed not only in their faces and jaws, but in the rest of their bodies too,” said Carol Ward of the the University of Missouri School of Medicine. “The old depiction of linear evolution from ape to human with single steps in between is proving to be inaccurate. We are finding that evolution seemed to be experimenting with different human physical traits in different species before ending up with Homo sapiens.” The new fossils, which all came from one individual unearthed in Kenya, include a hip joint like other Homo species, but the pelvis and thigh bone are thinner than those of Homo erectus, and may have come from the earlier Homo rudolfensis, or Homo habilis. “This doesn’t necessarily mean that these early human ancestors moved or lived differently, but it does suggest that they were a distinct species that could have been identified not just from looking at their faces and jaws, but by seeing their body shapes as well,” she explained. For more on the evolutionary history of early humans, see "Our Tangled Ancestory."