BIOL 005B Lecture Notes - Lecture 9: Marsupial, Eutheria, Carina Round
Document Summary
Tetrapods took advantage of two key features of the lobe-finned fish that allowed them. Limbs for supporting body and moving on land (evolved from muscular pectoral to move onto land fins) Tetrapods are gnathostomes, are osteichthyes, are sarcopterygii, that have limbs. In one lineage of lobe-fins, the fins became progressively more limb-like while. One of the most significant events in vertebrate history was when the fins of some the rest of the body retained adaptations for aquatic life lobe-fins evolved into the limbs and feet of tetrapods. Eggs without shells (eggs will dry out rapidly out of water) Evolution of amniotic egg , which contains membranes that protect the. The extraembryonic membranes are the amnion, chorion, yolk sac, and. Ability to use the rib cage to ventilate the lungs embryo . Allowed total departure from an aquatic/wet environment allantois. Amniotes : reptiles (including birds, dinosaurs, turtles, crocs, etc) and mammals. Reptiles: ectothermic vs. endothermic and the extinct dinosaurs.
