Two species of gorillas live in central equatorial Africa. Divergence between the Western gorillas (Gorilla gorilla) and Eastern Gorillas (Gorilla beringei) began between 0.9 and 1.6 million years ago and now the two species live several hundred kilometres apart. An international team of researchers including Olaf Thalmann of the University of Turku in Finland and Linda Vigilant of the Max Planck Institute for Evolutionary Anthropology in Germany found that the divergence of Western lowland gorillas and the Critically Endangered Cross River gorillas (Gorilla gorilla diehli) occurred more recently, about 17,800 years ago, during the Pleistocene era (BMC Evolutionary Biology, April 01, 2011).