Homo ergaster

Homo ergaster (meaning "working man") or African Homo erectus is an extinct chronospecies of the genus Homo that lived in eastern and southern Africa during the early Pleistocene, that is, between 1.9 million and 1.4 million years ago. It is one of the earliest hominins, which are those hominids that comprise the original members and species of the human clade after splitting from the line of the chimpanzees. (And Homo ergaster is variously thought to be ancestral to, or as sharing a common ancestor with, or as being the same species as, Homo erectus).

Interpreting Homo ergaster inevitably leads to Homo erectus, particularly regarding the taxonomy issues that persist within the scientific community of classifying the two species and separating their two lineages—if indeed they represent two separate lineages rather than one. Some palaeoanthropologists consider H. ergaster to be a variety of H. erectus, that is, the so-called African Homo erectus. Others call H. ergaster the direct ancestor of H. erectus, which then emigrated out of Africa into Eurasia and branched into a distinct species. Still others dispense with the specific epithet ergaster and make no such distinctions among fossils assigned to erectus.