ANT 131 Lecture Notes - Lecture 13: Brain Size, Paranthropus Aethiopicus, Homo Erectus
Document Summary
Changes in major structural features facilitating efficient bipedal locomotion. Changes were required for maintaining a stable, center of balance. Hominins move bipedally as standard and most efficient mode of locomotion. Committed to this and cannot locomote efficiently otherwise. Pelvis is shorter/broader, extends around the side (basin shape) Stabilizes weight transmission from lower back to hip. Toe is enlarged and brought in toward other toes. Head is more/less balanced on spine, requires less neck muscles to keep upright. Large muscular attachments long arms and fingers, curved fingers and toes. Probably a climber who was well adapted to walking on fours mostly arboreal. Savannach begins to emerge wide, open forest areas (new niches) Change in environment, cooling trend, makes landscape patchy. Encephalization widest part of cranial anatomy moves up to account for bigger brain. Australopiths (4. 2 3. 0 mya) more anatomically primitive/ancestral. Australopiths (2. 5 2. 0 mya) more changes in physical structure. Homo) v 9 species total v pronounced sexual.
