Homo ergaster: Difference between revisions

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==Description==
==Description==
H. ergaster had a rounded cranium and a prominent browridge. Compared to '''Australopithecus''', Its teeth were significantly smaller. Features that distinguish H. ergaster from H. erectus were thinner bones of the skull and the lack of an obvious ''sulcus'', or depression, immediately posterior of the browridge.<ref name=SI/><ref name=Heslip/><ref name=DmanisiHominids/><ref name=SIER992/>
H. ergaster had a rounded cranium and a prominent browridge. Compared to '''Australopithecus''', its teeth were significantly smaller. Features that distinguish H. ergaster from H. erectus were thinner bones of the skull and the lack of an obvious ''sulcus'', or depression, immediately posterior of the browridge.<ref name=SI/><ref name=Heslip/><ref name=DmanisiHominids/><ref name=SIER992/>


==Taxonomic status==
==Taxonomic status==

Revision as of 18:45, 24 December 2007

Homo ergaster
Fossil range: Pleistocene
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Subfamily: Homininae
Tribe: Hominini
Subtribe: Hominina
Genus: Homo
Species: H. ergaster
Binomial name
Homo ergaster
Colin Groves & Vratja Mazak, 1975

Homo ergaster (Greek derivation: working man), an early hominid (refer also to hominim), may either have been a predecessor of Homo erectus or an early group of Homo erectus. H. ergaster’s presence has been dated variously and may have ranged over a period of 1.9 to 1.5 million years ago. Remains of H. ergaster have been discovered in Kenya and Dmanisi in the Republic of Georgia.[1][2][3][4][5][6]

History of Discovery

Description

H. ergaster had a rounded cranium and a prominent browridge. Compared to Australopithecus, its teeth were significantly smaller. Features that distinguish H. ergaster from H. erectus were thinner bones of the skull and the lack of an obvious sulcus, or depression, immediately posterior of the browridge.[1][2][3][6]

Taxonomic status

Collections

Language in Homo ergaster

Occurrences/Sites

Temporal range

Associated artifacts

Tool making and use

H. ergaster evidently used large cutting tools of stone, primarily hand axes and cleavers. These tools represent an advanced stage of stone tool technology known as the Achulean stone tool industry now believed to have developed after hominid migration out of the region of eastern Africa.[1]

Important fossils

KNM ER 3733 cranium

Discovered by Bernard Ngeneo in Koobi Fora, Kenya in 1975, ER 3733 is a mature female that may have lived about 1.75 million years ago.[7]

KNM ER 3883 cranium

KNM ER 992 mandible

ER 992 was discovered in 1971 by Richard Leakey in Koobi Fora, Kenya. It is dated to about 1.5 million years ago. The ER 992 mandible shows a lighter build and smaller teeth than Homo erectus.[6]

Turkana Boy KNM WT 15000

Notes

  1. 1.0 1.1 1.2 Homo ergaster Department of Anthropology, National Museum of Natural History, Smithsonian Institute
  2. 2.0 2.1 Homo ergaster Steven Heslip, Michigan State University
  3. 3.0 3.1 Dmanisi hominids Dmanisi Site
  4. Doubting Dmanisi Pat Shipman (2000) American Scientist On-Line. Vol. 88: 6 (p. 491). Note: A great deal of the debate around the species found at Dmanisi has focused on the disagreement on characteristics of various species of hominid. One interpretation now has it thatHomo ergaster is shorthand for "the earliest part of the evolving ergaster/erectus lineage."
  5. Earliest Pleistocene hominid cranial remains from Dmanisi, Republic of Georgia: Taxonomy, Geological Setting, and Age L. Gabunia, A. Vekua, D. Lordkipanidze, C.C. Swisher III, R. Ferring, A. Justus, M. Nioradze, M. Tvalrelidze, S.C. Anton, G. Bosinski, O. J`ris, M.A. de Lumley, G. Majsuradzs, and A. Muskhelishvili (2000). Summary of article appearing in Science vol. 288, pages 1019-1025. May 12, 2000
  6. 6.0 6.1 6.2 KNM ER 992 Smithsonian Institute
  7. KNM ER 3733 Smithsonian Institute