To get a picture of how Lucy's species, Australopithecus afarensis, moved, scientists compare fossils to the bones of modern humans, as well as to the anatomy of "knuckle-walking" primates like ...

Body size is estimated from weight-bearing bones, including those in the hips. In Lucy's species, Australopithecus afarensis, the average adult male weighed near 110 pounds and stood around 4 feet ...

The bones that make up Ardi's feet suggest that humans and chimpanzees evolved separately. Lucy is also a female human-like fossilised skeleton, and dates from 3.2 million years ago. Lucy's bones ...