Morphology And Evolution Of Turtles PDF Download

How did flying birds evolve from running dinosaurs, terrestrial trotting tetrapods from swimming fish, and whales return to swim in the sea? These are some of the great transformations in the history of life; events that have captured the imagination of scientists and the general public alike. At first glance, these major evolutionary events seem utterly impossible. The before and after look so fundamentally different that the great transformations of the history of life not only seem impossible, but unknowable. The 500 million year history of vertebrates is filled with change and, as a consequence, every living species contains within its structure, DNA, and fossil record, a narrative of them. A battery of new techniques and approaches, from diverse fields of inquiry, are now being marshaled to explore classic questions of evolution. These approaches span multiple levels of biological organization, from DNA sequences, to organs, to the physiology and ecology of whole organisms. Analysis of developmental systems reveals deep homologies of the mechanisms that pattern organs as different as bird wings and fish fins. Whales with legs are one of a number of creatures that tell us of the great transformations in the history of life. Expeditions have discovered worms with a kind of head, fishes with elbows, wrists, and necks; feathered dinosaurs, and human precursors to name only a few. Indeed, in the last 20 years, paleontologists have discovered more creatures informative of evolutionary transitions than in the previous millennium. "The Great Transformations "captures the excitement of these new discoveries by bringing diverse teams of renowned scientists together to attack particular transformations, and to do so in a contents organized by body part--head, neck, fins, limbs, and then the entire bauplan. It is a work that will transform evolutionary biology and paleontology."