Expanding deserts drove mammals out of Eurasia into Africa

Zagros Mountains on the edge of Mesopotamia (Iran) . The formation of deserts on the Arabian Peninsula had a decisive impact on the migration and evolution of large mammals and our human ancestors over millions of years. That is the conclusion of a new study by an international research team led by Professor Madelaine Böhme of the Senckenberg Centre for Human Evolution and Palaeoenvironment at the University of Tübingen. The researchers reconstructed the climate history of the northern Arabian Peninsula from 12.5 to 2.5 million years ago using aridity-sensitive data obtained from rocks from Mesopotamia. This yielded new clues about the causes of animal migrations. The evolution of today's African savannah fauna took place in relative isolation over the past five million years. This has been known for some time, as has the fact that the ancestors of many savannah animals such as rhinos, giraffes, hyenas and big cats came from Eurasia.