BIO206H5 Lecture Notes - Lecture 11: Australopithecus Anamensis, Bipedalism, Australopithecine
Document Summary
What differentiates our hominin ancestors: large brain size (encephalization, dentition, tool making behavior standardized, habitual bipedal locomotion e. g. eoanthropus dawsoni (piltdown man) Disadvantages of bipedalism: more visible to predators, expose underbelly, limits ability to change direction, reduces speed, lower backaches, leg & foot injury. Ape like from waist up longer arms relative to legs; curved flexible fingers and toes: still tree climbing forward thrust of the face, large flaring cheek bones ape like human like from the waist down bipedal: s spine; forward foramen magnum; basin shaped pelvis. The black skull; wt 17000 broad face: massive projection of the upper face very large palate large area back teeth primitive traits, cranial capacity 410 cc compound crest prognathic (long snout ) round dental arcade. Cranial anatomy/ brain heavy and massive skull cheek bones flare out to the sides: sagittal & nuchal crest prominent brow ridges postorbital constriction (behind the eyes) cranial capacity 500 530 cc.
