Sentences with word «ergaster»

The size of the Ileret footprints is consistent with stature and body mass estimates for Homo ergaster / erectus, and these prints are also morphologically distinct from the 3.75 - million - year - old footprints at Laetoli, Tanzania.

Until the discovery of the first jawbone at Dmanisi 25 years ago, researchers thought that the first hominins to leave Africa were classic H. erectus (also known as H. ergaster in Africa).

Each individual researcher that sees ergaster as a valid taxon sees different specimens as belonging or not belonging to the taxon.

As a general rule of thumb, one can consider most attributed ergaster specimens to be early erectus geographically confined to Africa (however, this is not a hard and fast rule).

Several researchers have tried to define the difference between ergaster and erectus, P. Andrews and B. Wood among the more prominent.

They tend to see ergaster as a direct ancestor of modern humans with erectus being an evolutionary dead - end.

Dmanisi team members, among others, contend that the Georgian fossils belong to a single early population of H. erectus or to a single sub-subspecies, Homo erectus ergaster georgicus.

It is estimated that H. ergaster stood at 1.9 m (6ft3) tall with relatively less sexual dimorphism in comparison to earlier hominins.

Authors David Lordkipanidze, Marcia S. Ponce de León, Ann Margvelashvili, Yoel Rak, G. Philip Rightmire, Abesalom Vekua and Christoph P. E. Zollikofer say significant anatomical features of this skull can be found in earlier fossils assigned to the genus Homo, such as H. habilis, H ergaster and H. rudolfensis, and argue all comprise a single species within the genus Homo, with less variation among them than can be found within contemporary Homo sapiens.

This specimen has been attributed as a male ergaster by some, though most place it in H. erectus, and that is where it will be discussed in detail.

In short, H. ergaster does not show significant promise of lasting as a separate taxon due to several factors.

The taxon ergaster was first described in 1975 by C. Groves and V. Mazak.

P. Andrews defined seven autopomorphies that were characteristic of erectus, but which ergaster supposedly lacked.

At this time, ergaster basically means early H. erectus from Africa.

Other specimens that have been attributed to ergaster include KNM - ER 3733, SK 847, and KNM - ER 3883.

Also, more recent analyses by other researchers seem to indicate that even if ergaster specimens are considered as a different taxon than erectus, the erectus material is still closer to modern humans cladistically.

The size of the Ileret footprints is consistent with stature and body mass estimates for Homo ergaster / erectus...»

It is currently somewhat controversial whether H. ergaster or the later, Asian H. erectus was the direct ancestor of modern humans.

On the whole though, most researchers see too little difference between ergaster and erectus to form the basis of a species of the former, separated from the latter.

From top to bottom: Australopithecus afarensis (4 - 3 million years; ~ 40 kg, 130 cm); Homo ergaster (1.9 - 1.4 million years; 55 - 60 kg; ~ 165 cm); Neanderthal (200.000 - 30.000 years; ~ 70 kg; ~ 163 cm).

This name was chosen due to the discovery of various tools such as hand - axes and cleavers near the skeletal remains of H. ergaster.

H. ergaster may be distinguished from H. erectus by its thinner skull bones and lack of an obvious sulcus.

Homo ergaster («working man») is an extinct hominid species (or subspecies, according to some authorities) which lived throughout eastern and southern Africa between 1.9 to 1.4 million years ago with the advent of the lower Pleistocene and the cooling of the global climate.

(On opening day, a 4 - year - old boy stared at a pair of 1.8 - million - year - old Homo ergaster, protecting their half - butchered antelope from a vulture's attack, and blurted: «They're naked!

Since two million years ago, with the appearance of the species Homo ergaster, the body mass and the brain size of the hominins have risen considerably.

They propose that Homo habilis, Homo rudolfensis, Homo ergaster and other early hominids from the same time were all misnamed and were really just members of the species Homo erectus.

We learn in the February 27 issue of Science that a team working at Illeret, near Lake Turkana in Kenya, or many years the site of fossil finds, has uncovered two trails with footprints estimated to be 1.5 million years old and likely made by individuals assigned to Homo ergaster / erectus.

Judging from his anatomy, scientists believe this Homo ergaster was a tall youth about 13 to 15 years old.

Comparing the shape of the skull and teeth, H. ergaster had a similiar head structure to the Asian Homo erectus.

For example, some erectus do not possess these features, while some ergaster and some habilis do.

This period also witnessed the most dramatic increases in hominin brain size; early representatives of the Homo erectus sensu lato (Homo erectus and H. ergaster) in Africa had a brain that was > 80 % larger than the gracile australopithecine Australopithecus afarensis and ∼ 40 % larger than Homo (Australopithecus) habilis (Figure 1).

The type specimen for ergaster is KNM - ER 992.

Since then, other specimens have been attributed by various authors to ergaster, with most researchers placing the same fossils in erectus.

By 1.8 million years ago, a species called Homo ergaster was about as tall as living humans, with long legs and stiff feet that were only good for walking on the ground.

Homo erectus and H. ergaster were treated as a «super-species» referred to in the Figure key and text as «Homo erectus (sensu lato)», but distinct regional processes in brain size change were identified by separating the specimens by continent in the analyses.

B. Wood lists seven traits that link ergaster with H. sapiens, and that distinguish ergaster from erectus:

H. erectus is most closely related to H. ergaster, known from Africa and is dated to 1.5 - 1.8 million years ago.»

Early members of our own genus, Homo erectus, and its near relative, Homo ergaster, arose in the same region about 2.5 million years ago.

Supporters of the multiregional theory contend that modern human populations developed independently from archaic hominid (Homo erectus or Homo ergaster) populations in Africa, Europe, and Asia.

To these paleoanthropologists, this evidence suggests that the Asian and African sample represent separate species; the name «Homo ergaster» is given to the African fossils to formalize this species - level distinction.