Paranthropus

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Paranthropus
Temporal range: Pliocene-Pleistocene, 2.7–1.2 Ma
Smac Paläolithikum 013.jpg
Skull of Paranthropus boisei
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Family: Hominidae
Subfamily: Homininae
Tribe: Hominini
Subtribe: Australopithecina
Genus: Paranthropus
Broom, 1938
Type species
Paranthropus robustus
Species
Synonyms

Paranthropus (from Greek παρα, para "beside"; άνθρωπος, ánthropos "human") is a genus of extinct hominins that lived between 2.6 and 1.1 million years ago (mya). Also known as robust australopithecines, they were bipedal and probably descended from Australopithecus) 2.7 mya.[1]

The genus is characterised by robust skulls, with a prominent gorilla-like sagittal crests along the midline–which suggest strong chewing muscles–and broad, grinding herbivorous teeth. They likely consumed grasses and tough vegetation.[2]

Taxonomy[edit]

Discovery[edit]

A partial cranium and mandible of Paranthropus robustus was discovered in 1938 by a schoolboy, Gert Terblanche, at Kromdraai B (70 km south west of Pretoria) in South Africa. It was described as a new genus and species by Robert Broom of the Transvaal Museum. The site has been excavated since 1993 by Francis Thackeray of the Transvaal Museum. A date of at least 1.95 million years has been obtained for Kromdraai B.

"Zinjanthropus"[edit]

Cast of OH 5

Paranthropus boisei was discovered by Mary Leakey on July 17, 1959, at Olduvai Gorge, Tanzania (specimen OH 5). Her husband Louis considered naming it Titanohomo mirabilis, but instead decided on Zinjanthropus boisei in his 1959 Nature publication.[3][4] "Zinj" is an ancient Arabic word for the coast of East Africa, and "boisei" referred to Charles Watson Boise, an anthropological benefactor of the Leakeys.[5]

Locations of Paranthropus finds

However, this genus was rejected at Louis's presentation before the 4th Pan-African Congress on Prehistory as it was based on a single specimen, and was subsumed into Paranthropus. Austrian anthropologist Raymond Dart made his now famous remark, "…what would have happened if [the A. africanus specimen] Mrs. Ples had met Dear Boy [OH 5] one dark night."[6]

Validity[edit]

Currently, opinions differ whether Paranthropus is a synonym of Australopithecus. In either case, robust australopithecines are thought to have evolved from gracile Australopithecus.[7][8] In 2004, evolutionary biologist Richard Dawkins noted "perhaps several different species" of robust australopithecines, and "as usual their affinities, and the exact number of species, are hotly disputed."[1]

Phylogeny according to a 2015 study:[9]

Hominini

Outgroup

A. afarensis

A. africanus

Paranthropus

P. robustus

P. aethiopicus

P. boisei

Homo

Description[edit]

Paranthropus boisei reconstruction

Paranthropus had a massively built skull, with a prominent gorilla-like sagittal crest on the midline of the skull which anchored massive temporalis muscles used in chewing.[10] Most species had a brain about 40% the size of that of a modern human.[citation needed]

Paranthropus were bipeds, and their hips, legs, and feet resemble both its ancestor, Australopithecus afarensis, and modern humans.[11] There was some size variation between the different species, but most stood roughly 1.3 to 1.4 m (4 ft 3 in to 4 ft 7 in) tall and were quite well muscled.[citation needed] The pelvis is similar to A. afarensis, but the hip joint are smaller in Paranthropus. The similar hip structure between A. afarensis and Paranthropus implies that they had a similar walking gait.[12] However, their human-like big toe, well developed plantar aponeurosis, and more distal ankle joint show more support to the foot bones,[10] and a human "toe-off" gait cycle.

Paleoecology[edit]

Paranthropus first appeared roughly 2.7 million years ago (mya),[10] and Australopithecus had mostly disappeared by this time.[10] Paranthropus is known to have coexisted with H. habilis, and possibly H. erectus.[10]

Paranthropus had smaller braincases than Homo, yet they had significantly larger braincases than Australopithecus. Paranthropus is associated with stone tools both in southern and eastern Africa, although these tools are generally attributed to early Homo.[13] However, hand fossils from Swartkrans, South Africa, indicate that the hand of P. robustus was adapted for precision grasping, which could indicate and tool use.[14] Most Paranthropus species seem almost certainly not to have used language nor to have controlled fire, although they are directly associated with the latter at Swartkrans.[13]

Paranthropus are thought to have lived in wooded areas rather than the grasslands of Australopithecus.[citation needed] A study looking at carbon isotopes on the tooth enamel of P. boisei found that it heavily subsisted on C4 plants, possibly habitually consuming grasses (graminivore).[15] Another study looking at enamel fractures on their large molars found habitual consumption of tough vegetation (though not hard foods).[2][16]

The left foot of a P. boisei individual seems to have been bitten off by a crocodile,[17] possibly Crocodylus anthropophagus,[18] and another's leg shows evidence of leopard predation.[17]

See also[edit]

References[edit]

  1. ^ a b Dawkins, Richard (2004). The Ancestor's Tale: A Pilgrimage To the Dawn of Life. London: Weidenfeld & Nicolson. p. 77. ISBN 978-0-297-82503-6.
  2. ^ a b Towle, Ian; Irish, Joel D.; Groote, Isabelle De (2017). "Behavioral inferences from the high levels of dental chipping in Homo naledi" (PDF). American Journal of Physical Anthropology. 164 (1): 184–192. doi:10.1002/ajpa.23250. ISSN 1096-8644. PMID 28542710.
  3. ^ Morell, Virginia (2011). Ancestral Passions: The Leakey Family and the Quest for Humankind's Beginnings. Simon & Schuster. pp. 180–184. ISBN 9781439143872.
  4. ^ Morell, Virginia (2011). Ancestral Passions: The Leakey Family and the Quest for Humankind's Beginnings. Simon & Schuster. p. 185. ISBN 9781439143872.
  5. ^ Morell, Virginia (2011). Ancestral Passions: The Leakey Family and the Quest for Humankind's Beginnings. Simon & Schuster. p. 186. ISBN 9781439143872.
  6. ^ Morell, Virginia. "Ancestral Passions: The Leakey Family and the Quest for Humankind's Beginnings". Touchstone, 2011. p. 193
  7. ^ Pilbeam, D.R (1988). "Hominid evolution". In Harrison, G.A., Tanner, J.M., Pilbeam, D.R., & Baker, P.T. (eds.). Human Biology: An introduction to human evolution, variation, growth, and adaptability. Oxford University Press. pp. 104–143. ISBN 978-0-19-854144-8.CS1 maint: uses editors parameter (link)
  8. ^ Wood, B.A. (1994). "Evolution of australopithecines". In Steve Jones, Robert Martin & David Pilbeam (eds.). The Cambridge Encyclopedia of Human Evolution. Cambridge University Press. pp. 231–240. ISBN 978-0-521-32370-3.CS1 maint: uses editors parameter (link)
  9. ^ Saylor, Beverly Z.; Scott, Gary; Levin, Naomi E.; Deino, Alan; Alene, Mulugeta; Ryan, Timothy M.; Melillo, Stephanie M.; Gibert, Luis; Haile-Selassie, Yohannes (2015). "New species from Ethiopia further expands Middle Pliocene hominin diversity". Nature. 521 (7553): 483–488. doi:10.1038/nature14448. ISSN 1476-4687. PMID 26017448.
  10. ^ a b c d e Wood, B. & Strait, D. (2004). "Patterns of resource use in early Homo and Paranthropus". Journal of Human Evolution. 46 (2): 119–162. doi:10.1016/j.jhevol.2003.11.004. PMID 14871560.
  11. ^ Wood B, Richmond BG (July 2000). "Human evolution: taxonomy and paleobiology". Journal of Anatomy. 197 (1): 19–60. doi:10.1046/j.1469-7580.2000.19710019.x. PMC 1468107. PMID 10999270.
  12. ^ Macchiarelli R, Bondioli L, Galichon V, Tobias PV (February 1999). "Hip bone trabecular architecture shows uniquely distinctive locomotor behaviour in South African australopithecines". Journal of Human Evolution. 36 (2): 211–32. doi:10.1006/jhev.1998.0267. PMID 10068067.
  13. ^ a b Klein, R. (1999). The Human Career. University of Chicago Press.[page needed]
  14. ^ Susman RL (May 1988). "Hand of Paranthropus robustus from Member 1, Swartkrans: fossil evidence for tool behavior". Science. 240 (4853): 781–4. doi:10.1126/science.3129783. PMID 3129783.
  15. ^ Cerling TE, Mbua E, Kirera FM, et al. (June 2011). "Diet of Paranthropus boisei in the early Pleistocene of East Africa". Proceedings of the National Academy of Sciences of the United States of America. 108 (23): 9337–41. doi:10.1073/pnas.1104627108. PMC 3111323. PMID 21536914.
  16. ^ Sponheimer, Matt; Lee-Thorp, Julia; De Ruiter, Darryl; Codron, Daryl; Codron, Jacqui; Baugh, Alexander T.; Thackeray, Francis (2005-03-01). "Hominins, sedges, and termites: new carbon isotope data from the Sterkfontein valley and Kruger National Park". Journal of Human Evolution. 48 (3): 301–312. CiteSeerX 10.1.1.421.8468. doi:10.1016/j.jhevol.2004.11.008. ISSN 0047-2484. PMID 15737395.
  17. ^ a b Njau, J. K.; Blumenschine, R. J. (2012). "Crocodylian and mammalian carnivore feeding traces on hominid fossils from FLK 22 and FLK NN 3, Plio-Pleistocene, Olduvai Gorge, Tanzania". Journal of Human Evolution. 63 (2): 408–417. doi:10.1016/j.jhevol.2011.05.008.
  18. ^ Christopher A. Brochu, Jackson Njau, Robert J. Blumenschine and Llewellyn D. Densmore (2010). "A New Horned Crocodile from the Plio-Pleistocene Hominid Sites at Olduvai Gorge, Tanzania". PLoS ONE. 5 (2): e9333. Bibcode:2010PLoSO...5.9333B. doi:10.1371/journal.pone.0009333. PMC 2827537. PMID 20195356.CS1 maint: uses authors parameter (link)

External links[edit]