Australopithecus boisei. Artists impression of the skull and head of an Australopithecus boisei, a hominid that lived in Africa between about 2.3 to 1.3 million years ago. It had massive teeth, which are thought to have been an adaptation to a diet of tough plant foods. It is thought that its specialisation to such a diet led to its extinction after its environment changed. A. boisei was first discovered by Mary Leakey in the Olduvai Gorge, Tanzania, in 1959, and was named Zinjanthropus boisei. It is a robust australopithecine, and was heavierbuilt than the gracile australopithecines such as A. afarensis from which humans are thought to have evolved. This specimen is 1.8 million years old.