Australopithecine

The term Australopithecine ('australos' for short) refers to any species in the genus Australopithecus or the genus Paranthropus.Wood, B.; Richmond, B. G. (2000). "Human evolution: Taxonomy and paleobiology". Journal of Anatomy. 197 (Pt 1): 19–60. doi:10.1046/j.1469-7580.2000.19710019.x. PMC 1468107. PMID 10999270. These were bipedal hominids that lived in the Pliocene–Pleistocene epochs. 

 Description 
Australopithecines had ape-like and human-like qualities. They were mainly bipedal,Mai, L. L.; Owl, M. Y.; Kersting, M. P. (2005). The Cambridge Dictionary of Human Biology and Evolution. Cambridge & New York: Cambridge University Press. p. 45. ISBN 978-0-521-66486-8. like humans, but could probably climb and live at least partly in trees. Their arms were longer in proportion to their bodies,Wang, Nan; Ma, Jie; Jin, Dan; Yu, Bin (5 April 2024). "A Special Golden Curve in Human Upper Limbs' Length Proportion: A Functional Partition Which Is Different from Anatomy". BioMed Research International. 2017: 1–6. doi:10.1155/2017/4158561. PMC 5292375. PMID 28232941. which is useful when moving above the ground. The efficiency of their walking is difficult to estimate, but they were not so well adapted to bipedalism as humans.

The males were much larger than the females, which suggests a family arrangement with a dominant male and several females, as with modern apes. Nothing is known for certain about their use of tools.Klein R.G. The human career:human & biological cultural origins. 2nd ed, Chicago, chapter 4, p144.Wood B.A. 1994. Evolution of australopithecines. In Jones S. Martin R. & Pilbeam D. (eds) 2004. The Cambridge encyclopedia of human evolution. 8th ed, Cambridge University Press. 

The australopithecines had a brain size not much larger than modern apes. The great increase in brain size of modern man began with the genus Homo: it did not start with the australos. 

The arrangement of their teeth, especially the dental arcade, was similar to humans. They did not have the large canine teeth characteristic of present-day apes.

 Classification 
Australopithecines are in the hominin tribe of African apes that includes humans and all ancestors of Homo sapiens back to our split from the apes.

The australopithecines appeared in the late Miocene epoch:

Australopithecus, about four million years ago (mya)
Paranthropus, about 2.7 mya

When used alone, the term refers to both genera together. Australopithecus is sometimes referred to as the "gracile (slender) australopithecines", while Paranthropus are also called the "robust australopithecines".

 Other genera 
Kenyanthropus (3.5 to 3.2) mya is either a separate genus of australos, or a species of Australopithecus.
Ardipithecus (5.6 and 4.4) mya is a Miocene hominin. It had a grasping big toe, and therefore could live in trees as well as on the ground. The term "facultative biped" is used.
Sahelanthropus, also a Miocene hominin, lived about seven million years ago (mya). The relationships of this species to the australos is unclear.
Orrorin, at 6.1 to 5.7 mya is known from 20 pieces of bone, and its relationships are unclear. Orrorin is both earlier, by almost 3 million years, and more similar to modern humans than is A. afarensis. The main similarity is that the Orrorin femur is morphologically closer to that of H. sapiens than is Lucy's; there is, however, some debate over this point.Pickford, Martin (December 2001). "Martin Pickford answers a few questions about this month's fast breaking paper in field of Geosciences". Essential Science Indicators. 

 Ancestry 
A likely ancestor of the australopithecines is the Ardipithecus genus, which lived in East Africa. The genus Homo (humans) appears about 2.4 million years ago with Homo habilis. 

Australos moved into mixed savannah/woodland habitats as the climate cooled in the later Miocene. This explains their adaptations to walking or walking plus climbing. It also explains the changes to their diet and teeth, though not in detail. 

 List 
The australopithecines according to Briggs & Crowther are:Briggs D.G. & Crowther P.R. (eds) 2008. Palaeobiology II. Wiley, p600. 
Australopithecina 
Australopithecus
A. afarensis
A. africanus
A. anamensis
A. bahrelghazali
A. garhi
Paranthropus
P. robustus
P. boisei
P. aethiopicus
Ardipithecus
A. ramidus
Orrorin
Orrorin tugenensis
Sahelanthropus
Sahelanthropus tchadensis

 References 


Category:Miocene