Gorillas live in tropic and sub-tropic environments in the rain forests of Africa. They inhabit both the lowlands and mountains. When living in the lowlands, they live in forests and alongside swamps. The Albertine Rift is home to gorillas living in higher elevations.
Scientists classify African gorillas into three types: western, eastern and mountain. The split in the species occurred because of dramatic climate change during the Ice Age in which rain forests shrank and the vast savannah emerged between them. Rain forests re-emerged over the ages, but by that time the continent became so populated that the farthest gorillas could go were the Ubangi and Congo Rivers. In each area, deforestation caused habitable areas continue to shrink; some forest areas saw complete destruction, forcing gorillas to migrate to other regions. Today, gorillas often live in isolated forest areas and in crowded conditions.
Western, eastern and mountain gorillas have been separated for long enough that they have become genetically different from each other. Eastern gorillas have noticeably longer faces and wider chests than western gorillas. Western gorillas have brown hair on their heads in lieu of traditional black hair. Mountain gorillas have longer hair than either eastern or western gorillas. While they may look physically different, all gorillas share the quadrupedal knuckle walking style and live from 30 to 40 years in the wild.