In 1995, National Geographic Explorer-in-Residence Meave Leakey and her team made a very important discovery at Lake Turkana, Kenya. They found fossils of what turned out to be an Australopithecus anamensis. The discovery indicates that the date of the occurrence of bipedalism needed to be moved back by half a million years, to about 4.2 million years ago. This was not the first major paleoanthropologic discovery at Lake Turkana. In 1972, Bernard Ngenyeo, colleague to Richard and Meave Leakey, discovered the fossil of a Homo habilis, that was about 1.9 million years old. In 1984, the Leakey team found an almost-complete fossilized skeleton that was dated to about 1.5 million years ago. This was a Homo erectus and is famously known as "Turkana Boy."

This clip is an excerpt from the film Bones of Turkana. The film takes place in the area around ancient Lake Turkana. This area is known as a cradle of human life. There is evidence of hominids that lived here 4.2 million years ago. This film depicts the lives of some human ancestors.

This video from Bones of Turkana focuses on significant fossil discoveries made at Lake Turkana.

The video assumes some familiarity with the theory of evolution, the process of how organisms developed from earlier forms of life. Evolution is not a linear process, but a dynamic one. One species does not morph directly into another, but diverges from its ancestors. Evolution takes place throughout a population over a long period of time due to environmental pressures. This video sometimes uses the phrases "more advanced or less advanced" which actually don't apply to evolution. Species evolve to fit the particular environment that they are occupying at a given time, not to "advance" to a different evolutionary stage.