To get a picture of how Lucy's species ... Johanson at Hadar in 1973 -- were the parts of a knee joint. Like a human knee, it could "lock," allowing its owner to stand straight-legged.

Learn about our Editorial Policies. Textbooks will tell you that the human body contains 206 bones. But sometimes, there are 208. The fabella, a small bone in a tendon behind the knee, was lost over ...

The knee was much older than the earliest ... Lucy gave us an unprecedented picture of her kind. In 1974, Lucy showed that human ancestors were up and walking around long before the earliest ...