GEOL 107 Lecture Notes - Lecture 24: Feathered Dinosaur, Deinonychus, Maniraptora
Document Summary
Geol 107 / geoe 207 -- history of life. In previous lectures, we have seen that insects evolved flight in the carboniferous, and that gliding reptiles first appear in the permian. Modern gliding tetrapods include frogs, snakes, lizards, and 65 species of mammals. Only three tetrapod groups have ever evolved flapping flight: pterosaurs, birds, and bats: pterosaurs (diorama #25) are an archosaur sister-group to the dinosaurs. Pterosaurs were the first tetrapods to fly, and include the largest animals to have ever flown. Pterosaur wings were supported on a highly modified elongate 4th finger. Evolutionary history mirrors the dinosaurs; first appeared in the late triassic and went extinct at the end of the cretaceous. Very well discussed in your textbook (cowen, 2013, p. 169-173: origin of birds. The origin of birds used to be one of the great controversies in paleobiology. In 1870 thomas huxley (darwin"s chief advocate) proposed that birds evolved from dinosaurs.