Lecture 8 The evolution of primates and hominids Geologic Time Scale Overview of the skeleton Fossil Primates Adapids 45 mil BP Lemur-like Omomids 45 mil BP Tarsier-like Aegyptopithecus Fayum, Egypt 32 mil BP Ancestral to catarrhines Proconsul Kenya 20 mil BP Dental ape Dryopithecus Europe 13 mil BP Full ape Sivapithecus India 14-8 mil BP Ancestral to orangutans Gigantopithecus China 9-1 mil BP Largest primate ever What is a hominid?- Traits cited as to why humans are distinctive. Large brains Language Culture, religion Tool Use Bipedalism Piltdown found english gravel quarry associated w/ extinct animals 1911 found, 1912 published- Charles Dawson Eoanthropus dawsoni Large brain, ape-like jaw w/ human wear pattern on teeth 1915 more pieces found Other fossils found didn’t fit; Neandertal, Erectus, later on Australopithecines 1950 tests done proved fraud; human skull, orang jaw w/ filed teeth recent origin Why accepted? Fit hypothesis- large brain made us human, came first Was British fossil- dearer to British scientists than other finds Bipedalism Characteristics Foramen magnum Spinal-curve Bowl-like pelvis Angled knee joint In-line big toe and arched foot Origins- What’s it good for? Carry things See over grass Tool-use Throwing Long-distance movement Heat stress Food gathering The earliest homonids Ardipithecus ramidus Where found; regions and principle sites Hadar, Ethiopia; 1992 Tim White Distinguishing characteristics Foramen magnum more forward Bipedal? Large canines w/ vertical root, thin enamel Time ranges 4.4 MYA Cranial capacity Unknown- prob chimp sized ~400cc Diet, habitat, & tool use forest, fruit?, no tools Australopithecus anamensis Where found; regions and principle sites Lake Turkana, Kenya; 1995 Maeve Leakey & Allen Walker Distinguishing characteristics Bipedal Large canines w/ vertical root, thick enamel Time ranges 4.2-3.9 MYA Cranial capacity Unknown- prob chimp sized ~400cc Diet, habitat, & tool use Forest, more omniverous?, no tools Lucy’s species Australopithecus afarensis Where found; regions and principle sites Hadar, Ethiopia; 1973-5; Don Johanson Laetoli, Tanzania; 1974-77; Mary Leakey Distinguishing characteristics Bipedal; w/long arms, curved fingers & toes, conical ribcage Large canines but tooth row more human-like (parabolic) Large amount of sexual dimorphism; 3 to 5 ft tall Very prognathic (lower face sticks out) Time ranges 4-3 MYA Cranial capacity 380-500 cc, avg 440cc Diet, habitat, & tool use Mixed forest & savanna, prob fairly omniverous, no tools The original Australopithecine Australopithecus africanus Where found; regions and principle sites Taung, S. Africa; 1924; Raymond Dart Sterkfontein, S. Africa; 1936; Robert Broom Distinguishing characteristics Bipedal, w/ similar proportions to A. afarensis Smaller canines and parabolic tooth row Less prognathic than earlier forms Time ranges 3-2.3 MYA Cranial capacity 435-530 cc, avg 450 cc Diet, habitat, & tool use Fruits & leaves, mixed forest & savanna, no tools