ARCH 131 Lecture Notes - Lecture 8: Australopithecus Afarensis, Homo Habilis, Australopithecus Africanus
Document Summary
Hip and knee joint are fully bipedal. Hips aren"t sexually dimorphic (indicates no obstetric dilemma ) Tooth development: afarensis grew up faster than humans but slower than chimpanzee. A longer childhood was starting to evolve. Selam"s skeleton tells us about our spines, too. Selam, lucy"s child : 3. 3 million years old. Hominine ancestors (and today"s apes) have 13. Divergent toe similar to ardipithecus but 1mya later!! Dental microwear study on p boisei suggests vegetation and fruit diet. Smaller teeth & jaws than afarensis and paranthropus. Likely gave rise to the lca of genus homo. Smaller face and teeth than a farensis ;jaw still u-shaped. Humanlike pelvis + apelike feet: a hyper-pronating walk - derived unique form of bipedalism. Brain size jumped to 631cc (upper end: 775cc) H habilis is a species of convenience: may be a diverse cluster rather than a single species. Earliest evidence: cut-marked bones at 3. 5mya (dikika, ethiopia)