In 1974, a very old skeleton was found in Africa. The bones were those of young female, approximately 20 years old when she died. Scientists named this "young lady" Lucy. About 3 million years ago, when Lucy was alive, she was rather short, about 4 feet tall, and probably weighed about 50 pounds. Her brain was about the size of an orange. Her bones showed she probably walked erect, although she still had the ability to climb trees easily. There were no signs of broken bones or teeth marks that might show why she died. Scientists suspect that she probably fell into a lake or river and drowned. Scientists are like detectives. They can tell a great deal from a skeleton, even when it is 3 million years old!