Homo ergaster

Homo ergaster
Temporal range: 1.9–1.4 Ma Early Pleistocene
Homo ergaster.jpg
KNM-ER 3733 (1.6 Million years ago, discovered 1975 at Koobi Fora, Kenya)
Scientific classification edit
Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Primates
Suborder:Haplorhini
Infraorder:Simiiformes
Family:Hominidae
Subfamily:Homininae
Tribe:Hominini
Genus:Homo
Species:
H. ergaster
Binomial name
Homo ergaster
Groves and Mazák, 1975[1]

Homo ergaster, also Homo erectus ergaster[2] or African Homo erectus is an extinct chronospecies of the genus Homo that lived in eastern and southern Africa during the early Pleistocene, between about 1.9 million and 1.4 million years ago.

Originally proposed as a separate species, H. ergaster is now mostly considered either an early form, or an African variety, of H. erectus.[3][4][5]

The binomial name was published in 1975 by Groves and Mazák.[1] The specific epithet, "ergaster", is derived from the Ancient Greek ἐργαστήρ ergastḗr - "workman", in reference to the advanced lithic technology developed by the species, thereby introducing the Acheulean industry.

KNM-ER 2598, a "H. erectus-like" occipital bone stands as the earliest evidence for H. erectus in Africa at approximately 1.9 million years ago (contemporary with Homo rudolfensis).[6] There is a fossil gap between 1.9 and 1.6 million years ago, KNM-ER 3733 is the oldest known H. ergaster skull dated to about 1.6 million years ago.[7] Its survival past 1.4 million years ago is uncertain, again due to a fossil gap, the next available African fossils allowing reliable morphological analysis are those of Homo rhodesiensis (African H. heidelbergensis), at 0.6 million years ago.

Discovery and representative fossils

South African palaeontologist John T. Robinson discovered in 1949 a mandible of a new hominin in southern Africa, which he named Telanthropus capensis and which today is classified as Homo ergaster.[8] That taxon was first applied to a mandible found near Lake Rudolf (now Lake Turkana), Kenya, by Colin Groves and Vratislav Mazák in 1975; dubbed KNM-ER 992, it became the type-specimen of the species. A near-complete skeleton of H. ergaster, KNM-WT 15000, or "Turkana Boy", was discovered in 1984 at Lake Turkana by Kamoya Kimeu and Alan Walker. It is dated to 1.6 million years ago (mya) and is one of the most complete early hominin fossils found to date.