Australopiths and Pre-Australopiths

Australopiths Best known group of African hominid species Two groups Australopithecus (gracile forms) Paranthropus (robust forms) Lived from 4.2- 1 mya They are all clearly bipedal Relatively small brains They have large teeth, particularly the back teeth, with thick to very thick enamel on molars.

Australopithecus afarensis Donald Johanson and his team (including Tim White) discovered Lucy in the Afar region of Ethiopia Discovered in 1974 First skeleton of an Early hominid until last year

Showed bipedalism preceded encephalization But not completely the same as us Cranial capacity 350cc 3.2 mya Showed bipedalism preceded encephalization

Mary Leakey discovers Laetoli Footprints Shows 54 individuals walking upright Radioactive dating places these footprints at 3.59 to 3.75mya

Paranthropus boisei 2.6 – 1.8 mya Huge jaw Large molars Large sagital crest Cranial capacity 530cc First discovered by anthropologist Mary Leakey on July 17, 1959, at Olduvai Gorge, Tanzania,

Paranthropus (Robust Australopiths) Many different species and fossils from all over Africa Large, deep, lower jaws. Large molars Sagital crest What do think this means?

Paranthropus aethiopicus 2.5 mya Lake Turkana, Kenya Cranial capacity 410cc

Pre-Australopiths (7.0-4.4 mya) Sahelanthropus Found in Chad at Toros-Menalla 2001 Faunal Dating places it around 7 mya Small Braincase no larger than modern chimpanzee Small vertical face is hominid like feature What ape like features do you see?

Ardipithecus ramidus Discovered in 1994 by Tim White (U.C. Berkley) and Lovejoy (Kent State) In 1994 just found portion of jaw and a few teeth Found in Middle Awash of Ethiopia Complete find published in Science October 2009 Mostly complete

Bipedal Wouldn’t be able to run long distances Grasping toe Small brain Small canines Cranial capacity 350-500cc Dated Volcanic Ash above and below fossils 4.4 mya