Researchers from Penn State University and Rutgers suggested that a series of rapid environmental change in East Africa, which occurred about 2 million years ago, is the cause of severe human evolution.

Landscapes habitats ancient people several times were replaced by forests, meadows and pastures - about five or six times over 200,000 years. These changes have occurred very rapidly, and each transition takes from several hundred to several thousand years.

Scientists investigated organic material and fossil molecules ancient organisms using spectrometry gas chromatography. The obtained data allowed them to recover the types of vegetation that grew in the area in a very specific intervals.

The results showed that the environment is changing quickly between forests, meadows and pastures. The scientists also found a correlation between changes in the environment and the temperature of the surface of the sea, and that the amount of precipitation was greater when the region grew dense forest.