Australopithecina

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The division of living beings into systematics is a continuous subject of research. Different systematic classifications exist side by side and one after the other. The taxon treated here has become obsolete due to new research or is not part of the group systematics presented in the German-language Wikipedia.

Australopithecus sediba (original),
head of the holotype

The australopithecine or australopithecines (rarely also: Australopithen ) are an extinct systematic group of Hominini within the family of great apes (hominids). It includes the genus Australopithecus and - if the so-called robust Australopithecus species are split off into a separate genus - the genus Paranthropus . Also belonging is Kenyanthropus platyops ; its status as the (only) member of its own genus is, however, controversial among paleoanthropologists ; in many cases this species is classified as a special form of the genus Australopithecus . From the Australopithecina, Homo rudolfensis and Homo habilis emerged, the earliest representatives of the genus Homo .

After its discovery, the fossils known today as Ardipithecus were initially placed with Australopithecus . The genus is now interpreted together with Sahelanthropus and Orrorin as the temporal forerunners of the Australopithecines ("pre-Australopithecines"), and it is discussed that all three genera could possibly be assigned to a single genus after further finds have been found.

Australopithecus was also used as a synonym for pre-humans , literally translated it means something like "southern monkey". All sites are in Africa .

properties

Curved finger bones by " Ardi "

The Australopithecina existed in the Pleistocene approximately between 3.5 and 1.8 million years ago. During this period, many of the species belonging to this group developed the ability to walk upright . In many species, long arms as well as finger and toe bones that are slightly bent due to frequent shackling and climbing are evidence of a regular stay in trees. In all the species described so far, the shape of the teeth indicates that they were vegetarians, whereby the so-called robust Australopithecus species, as evidenced by their strong lower jaw and strong masticatory muscles, were particularly well adapted to this diet. The body weight of the individuals of all species is estimated at 27 to 45 kg, their height at 100 to 150 cm, whereby the female individuals were significantly smaller than the males.

habitat

All of the australopithecine finds known to date lived in habitats in which gallery forests had formed along watercourses that merged into scrubland and open savannahs . The leaves and fruits of trees and grass were thus available as food; Paranthropus specialized in a hard fiber diet made from grass.

With the help of strontium isotope analysis , clues for gender-specific differences in lifestyle were found. The analysis was based on the fact that the ratio of 87 Sr to 86 Sr in the enamel is a direct consequence of the same ratio in the diet at the time of tooth enamel formation in adolescence and that this in turn largely depends on the ratio in the soil. It is also considered certain that the proportions in the dolomitic soil have not changed fundamentally since the death of the Australopithecines. The 87 Sr / 86 Sr ratio of the examined teeth of Australopithecus africanus and Paranthropus robustus from Sterkfontein and Swartkrans showed that the former owners of the larger teeth had only consumed food within five to six kilometers of the site, while the owners of the smaller teeth had a significantly expanded living space. Since the different tooth sizes are the result of a sexual dimorphism , the large teeth are assigned to the male, the smaller teeth to the female individuals. Accordingly, the male australopithecines were largely localized from birth , while the female migrated from other populations , which was interpreted as an indication of exogamy ; Female exogamy and male local loyalty also exist in the chimpanzees , while in the gorillas male and female individuals migrate equally to other populations after sexual maturity.

Historical

Paranthropus aethiopicus ,
a "robust" australopithecine

Until a few years ago only humans were referred to as Hominidae, the great apes, however, as Pongidae, and both groups were thus considered to be two separate families; the Australopithecina were then considered to be the subfamily Australopithecinae ; The term australopithecines also comes from this classification . Today, however, humans and great apes are grouped together in the Hominidae family. The Australopithecina are also considered a paraphyletic taxon, so they do not include all descendants of their last common ancestor: The representatives of the genus Homo, to which modern humans also belong, arose from the Australopithecines, but are traditionally not included in this group. For this reason, the taxon is not recognized by representatives of a modern form of systematics, cladistics .

See also

Individual evidence

  1. ↑ Donald Johanson : Lucy and Her Children. 2nd updated and expanded edition. Elsevier Verlag, Munich 2000, ISBN 978-3-8274-1670-4 , p. 128.
  2. ↑ Yohannes Haile-Selassie , Gen Suwa, Tim White : Late Miocene Teeth from Middle Awash, Ethopia, and early hominid dental evolution. In: Science . Volume 303, 2004, pp. 1503-1505.
  3. ↑ a b See for example the “Systematic Overview” in: Grzimeks Tierleben. Volume 11 (= mammals 2), dtv, 1979, p. 508. The genus Australopithecus is described here as the "genus Vormensch".
  4. ↑ Margaret J. Schoeninger: In search of the australopithecines. In: Nature . Volume 474, 2011, p. 43, doi: 10.1038 / 474043a
  5. ↑ The description of the properties follows Donald Johanson: Lucy and her children, p. 41.
  6. ↑ Margaret J. Schoeninger: In search of the australopithecines. In: Nature. Volume 474, 2011, p. 43, doi: 10.1038 / 474043a
  7. ↑ Thure E. Cerling et al: Diet of Paranthropus boisei in the early Pleistocene of East Africa. In: PNAS . Tape. 108, No. 23, 2011, pp. 9337-9341, doi: 10.1073 / pnas.1104627108
  8. ↑ Sandi R. Copeland et al: Strontium isotope evidence for landscape use by early hominins. In: Nature . Volume 474, No. 7349, 2011, pp. 76-78, doi: 10.1038 / nature10149
  9. ^ Bernard Wood , Brain G. Richmond: Human evolution: taxonomy and paleobiology. In: Journal of Anatomy , Volume 197, No. 1, 2000, pp. 19-60, doi: 10.1046 / j.1469-7580.2000.19710019.x