Whales & Dolphins
Evolution: Education and Outreach. Cetaceans whales, dolphins, and porpoises are an order of mammals that originated about 50 million years ago in the Eocene epoch. Even though all modern cetaceans are obligate aquatic mammals, early cetaceans were amphibious, and their ancestors were terrestrial artiodactyls, similar to small deer. The transition from land to water is documented by a series of intermediate fossils, many of which are known from India and Pakistan. We review raoellid artiodactyls, as well as the earliest families of cetaceans: pakicetids, ambulocetids, remingtonocetids, protocetids, and basilosaurids. We focus on the evolution of cetacean organ systems, as these document the transition from land to water in detail.
Whales, Dolphins and Porpoises edited by Annalisa Berta, with a large number of expert contributors, is a comprehensive reference guide to cetaceans designed for the educated audience or an interested student, but not a specialist in the field. Overall the book is well-written, highly accurate, and nicely illustrated with useful tips for the dedicated whale-watcher or nature lover. The book belongs on any serious naturalist cruise ship because it offers good guides for identifying various dolphin and whale species based on their blow, surfacing and diving patterns—in addition to telltale coloration, size, and shape. The volume also details which species even cetacean biologists might easily confuse with each other. It is a comprehensive reference book and a useful starting place for any student interested in learning about cetaceans. Whales, Dolphins and Porpoises is organized into three major sections. This section also provides locations for observing cetaceans and techniques for doing so.
PDF | In the Encyclopedia of Whales, Dolphins and Porpoises, award-winning author and whale researcher Erich Hoyt takes readers into the.
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Porpoises are a group of fully aquatic marine mammals, all of which are classified under the family Phocoenidae , parvorder Odontoceti toothed whales. There are seven extant species of porpoise. They are small toothed whales that are very closely related to oceanic dolphins. The most obvious visible difference between the two groups is that porpoises have shorter beaks and flattened, spade-shaped teeth distinct from the conical teeth of dolphins. Porpoises, and other cetaceans , belong to the clade Cetartiodactyla with even-toed ungulates , and their closest living relatives are the hippopotamuses , having diverged from them about 40 million years ago.
E-mail address: eburgess neaq. John H. Use the link below to share a full-text version of this article with your friends and colleagues. Learn more. Volume 32 , Issue 3. The full text of this article hosted at iucr.