Homo erectus is an extinct species of the genus Homo, which originated in Africa and spread as far as China and Java. Depending on the definition of the species, it is considered to be either a direct ancestor of modern humans, or a separate species which co-existed with the distinct Homo neanderthalensis and a third branch which is a direct ancestor of modern humans. H. erectus originally migrated from Africa during the Early Pleistocene, possibly as a result of the operation of the Saharan pump, around 2.0 million years ago, and dispersed throughout much of the Old World. Fossilized remains 1.8 and 1.0 million years old have been found in Africa and Europe Vietnam, and China