BSC 116 Lecture Notes - Lecture 13: Australopithecus Afarensis, Homo Ergaster, Middle Ear

• School: University of Alabama
• Department: Biological Sciences
• Course: BSC 116
• Professor: Phillip Harris

Document Summary

Skin less permeable to water/gas: use ribs (rather than throat) to breathe. Living amniotes are represented by two major clades: reptiles, parareptiles (extinct, diapsids, archosaurs- dinosaurs (+ birds) and crocs, extinct lineages: pterosaurs,,, ichthyosaurs, plesiosaurs. Lepidosaurs- lizards and snakes: turtles, synapsids: mammals, reptiles are really a paraphyletic group, arose around 320 my, things like tuataras, lizards, snakes turtles, and crocodiles, body with hard, keratin scales: protection, generally oviparous: lay shelled eggs on land. Some species viviparous: embryo retained in mother (no shell: ectothermic- body heated by environment vs. endothermic- use higher metabolism to generate heat, birds and mammals evolved from reptile ancestors, reptilian characters ancestral rather than derived. reptiles recognized by what they are not: non-bird, non-mammal amniotes: tuataras, lizards, and snakes (lepidosaurs); turtles are something else, three extant lineages of lepidosaurs, tuataras- 2 species on islands around new zealand. From 230-65 my: represented by dinosaurs: two major lineages of dinosaurs, ornithischian- bird-hipped