Horns, Tusks, and Flippers: The Evolution of Hoofed Mammals pdf par Robert Schoch
Since the extinction of the dinosaurs, hoofed mammals have been the planet's dominant herbivores. Native to all continents except Australia and Antarctica, they include not only even-toed artiodactyls (pigs, hippos, camels, deer, antelopes, giraffes, sheep, goats, and cattle) and odd-toed perissodactyls (horses and rhinos), but also tethytheres (elephants and their aquatic relatives, manatees and seas cows) and cetaceans (whales and dolphins), which descended from hoofed land mammals. Recent paleontological and biological discoveries have deepened our understanding of their evolution and in some cases have made previous theories obsolete. In Horns, Tusks, and Flippers, Donald R. Prothero and Robert M. Schoch present a compelling new evolutionary history of these remarkable creatures, combining the latest scientific evidence with the most current information about their ecology and behavior.Using an approach based on cladistics, the authors consider both living and extinct ungulates. Included in their discussion are the stories of rhinos, whose ancestors include both dinosaur-sized hornless species and hippo-like river waders; elephants, whose earliest ancestors had neither tusks nor trunks; and whales, whose descent from hoofed mesonychids has never properly been described for the lay audience. Prothero and Schoch also update the evolutionary history of the horse, correcting the frequent errors made in textbooks and popular works, and they make available to the general public new evidence about the evolution of camels, horned antelopes, and cattle. In addition, they raise important conservation issues and relate anecdotes of significant fossil finds.Scientifically accurate and up to date, generously illustrated, and clearly written, Horns, Tusks, and Flippers is a useful and much-needed resource for specialists in the fields of paleontology, zoology, ecology, and evolutionary biology, as well as for general readers interested in learning more about the story of life on earth.