BIOLOGY 1M03 Lecture 17: BIO 1M03 - Hominins
14 Jun 2020
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Hominins: refer to people (homo sapiens) and our upright ancestors, chimps are the outgroup (not included, characterized by: Speci c changes in chewing design: teeth, jaws, and skulls. Upright posture: bipedalism is rare (mammals: kangaroos, kangaroo rats), as far as we know, bipedalism and quadrupedalism are about equally e cient, why did it evolve, for harvesting food in trees, evolved early and retained in humans. Feet to grasp small branches, hands to balance and collect food. Orangutans and chimps sometimes move bipedally in trees. Butl some close ancestors are more monkey-like: for harvesting fruit from small trees. E cient (don"t have to get up and down between trees: for keeping cool. But: bipedality evolved while hominins were in the woods. In mosaic habitats: for carrying things. Gradual evolution: hominins" evolution of upright posture depended on evolutionary history and circumstance. Built on previous adaptations: almost certainly led to further evolutionary change:
