Lucy the Australopithecus is the oldest known human ancestor. When her bones were discovered in a shallow stream in the country of Ethiopia 42 years ago, it was a huge scientific discovery. After all, she is approximately three million years old and is considered the oldest known human ancestor. Since her discovery, anthropologists have been studying her to learn more about early humans and what life might have been like back then. Now, one scientist thinks that he might have pieced together how Lucy died. After studying Lucy’s skeleton and consulting with experts, he believes that Lucy most likely died from falling from somewhere really really high — perhaps a tree, where she might have climbed up trying to protect herself from large animals.