Paranthropus is a genus of extinct hominin which contains two widely accepted species: P. robustus and P. boisei. However, the validity of Paranthropus is contested, and it is sometimes considered to be synonymous with Australopithecus. They are also referred to as the robust australopithecines. They lived between approximately 2.6 and 0.6 million years ago (mya) from the end of the Pliocene to the Middle Pleistocene.
Paranthropus is characterised by robust skulls, with a prominent gorilla-like sagittal crest along the midline—which suggest strong chewing muscles—and broad, herbivorous teeth used for grinding. However, they likely preferred soft food over tough and hard food. Paranthropus species were generalist feeders, but P. robustus was likely an omnivore, whereas P. boisei was likely herbivorous and mainly ate bulbotubers. They were bipeds. Despite their robust heads, they had comparatively small bodies. Average weight and height are estimated to be 40 kg (88 lb) at 132 cm (4 ft) for P. robustus males, 50 kg (110 lb) at 137 cm (4 ft 6 in) for P. boisei males, 32 kg (71 lb) at 110 cm (3 ft 7 in) for P. robustus females, and 34 kg (75 lb) at 124 cm (4 ft 1 in) for P. boisei females.
They were possibly polygamous and patrilocal, but there are no modern analogues for australopithecine societies. They are associated with bone tools and contested as the earliest evidence of fire usage. They typically inhabited woodlands, and coexisted with some early human species, namely A. africanus, H. habilis and H. erectus. They were preyed upon by the large carnivores of the time, specifically crocodiles, leopards, sabertoothed cats and hyenas.
The genus Paranthropus was first erected by Scottish-South African palaeontologist Robert Broom in 1938, with the type species P. robustus.[1] "Paranthropus" derives from Ancient Greek παρα para beside or alongside; and άνθρωπος ánthropos man.[2] The type specimen, a male braincase, TM 1517, was discovered by schoolboy Gert Terblanche at the Kromdraai fossil site, about 70 km (43 mi) southwest of Pretoria, South Africa.[1] By 1988, at least six individuals were unearthed in around the same area, now known as the Cradle of Humankind.[3]
In 1948, at Swartkrans Cave, in about the same vicinity as Kromdraai, Broom and South African palaeontologist John Talbot Robinson described P. crassidens based on a subadult jaw, SK 6. He believed later Paranthropus were morphologically distinct from earlier Paranthropus in the cave—that is, the Swartkrans Paranthropus were reproductively isolated from Kromdraai Paranthropus and the former eventually speciated.[4] By 1988, several specimens from Swartkrans had been placed into P. crassidens. However, this has since been synonymised with P. robustus as the two populations do not seem to be very distinct.[3]
In 1959, P. boisei was discovered by Mary Leakey at Olduvai Gorge, Tanzania (specimen OH 5). Her husband Louis named it Zinjanthropus boisei because he believed it differed greatly from Paranthropus and Australopithecus. The name derives from "Zinj", an ancient Arabic word for the coast of East Africa, and "boisei", referring to their financial benefactor Charles Watson Boise.[5] However, this genus was rejected at Mr. Leakey's presentation before the 4th Pan-African Congress on Prehistory, as it was based on a single specimen.[6] The discovery of the Peninj Mandible made the Leakey's reclassify their species as Australopithecus (Zinjanthropus) boisei in 1964,[7] but in 1967, South African palaeoanthropologist Phillip V. Tobias subsumed it into Australopithecus as A. boisei. However, as more specimens were found, the combination Paranthropus boisei became more popular.[8]