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Cetaceans Of Europe
Cetacea (; , ) is an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel themselves through the water with powerful up-and-down movement of their tail which ends in a paddle-like fluke, using their flipper-shaped forelimbs to maneuver. While the majority of cetaceans live in marine environments, a small number exclusively reside in brackish water or fresh water. Having a cosmopolitan distribution, they can be found in some rivers and all of Earth's oceans, and many species inhabit vast ranges where they migrate with the changing of the seasons. Cetaceans are famous for their high intelligence and complex social behaviour as well as for the enormous size of some of the group's members, such as the blue whale which reaches a maximum confirmed length of 29.9 meters (98 feet) and a weight of 173 tonnes (190 short to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
