MAMMALIA a goal. Aquatic. Body shape of fish, forelimb and tail fins have become, hind degradation. Hairless skin, no ear shell. Viviparous, breastfeeding, breathing with the lungs, generally feed on fish and plankton. Can be divided into toothed whales and baleen whales suborder.
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No. 2
Cetacea (cetacea) 【Category】 status Eukaryotic domain eukaryota Animals fauna Chordate phylum chordata door Vertebrate subphylum vertebrata Mammalia mammalia; mammals Subclass tberia true beast 【Origin】 From the anatomical point of view, many of the characteristics of whales have shown that for highly adapted to life in the sea, however, anatomical evidence, and not enough to answer many questions about the origin of whales. But from the perspective of biochemistry and genetics, whales closer relationship with the ungulates, and the fossil record (about 50 million years ago) also support the whales by ungulates evolved. The ancestors of whales, most likely produced in North America, Europe and Asia --- terrestrial ungulate animal subjects in the jaw (in animal subjects, mesonychidae). Some members of Xenopus animal in the petite such as dogs, and some are tall as a bear, but many are the evolution of animals from small and large, so whales may be in the jaw by a small animal evolved. Supposedly, the teeth small, in shallow water fishing in the Xenopus animal, by gradually changing the form of amphibious life, and then in the long evolution into a variety of whales and dolphins today. Known, first appeared in the ancient whale whale suborder (archaeocetes) of the original whale Division (protocetidae). Original whale species have all appeared in 50 million years ago, fossil distribution in Asia, Africa and North America. Pakistani scientists are found in today's pakicetus understand more, this life in 5300-5000 million years ago, fossils, is a jet hole (nose) has been moved to the rear, with a narrow ventricle, and still has the hind legs of animals. In the same period found in the Indian rock fossil evidence also shows that, in the early cetaceans, the unimaginable has had high ecological diversity. The more advanced of the ancient whale suborder animals, reptiles have been identified as the armed toothed whales Branch (basilosauridae). About the survival of the animal subjects in 4500-3800 million years ago, although the first geologist in louisiana found the United States, but similar fossils are also widely found in New Zealand and even Antarctica. This findings suggest that the ancient whale suborder 4,000 million years ago had already spread to the southern waters. The more advanced of the ancient whale suborder of the other branch is at least 6 animals of the dorudontinae, they have narrower upper jaw, which may be filter-feeding; or toothed whales, as are most students like to help to construct rapidly caught fish, squid and birds. It was a long evolution, the ancient whale suborder finally Oligocene (oligocene) a way into extinction. But the whale family, the other two branches, the baleen whales suborder (mysticeti) and the toothed whale suborder (odontoceti), but out of the past history, derived from 13 families and nearly 80 species of all kinds of fascinating creatures, enrich our marine vitality. 】 【Morphology Biology Description Like all mammals, whales have lungs, are warm-blooded animals, the pups fed by the breast-feeding, there is little hair. Large lung volume, total ventilation with each breath, the use of oxygen after diving economy, whales can dive to 30 to 70 minutes, or even a long time to come up for air again. Most small whale who is shallow dive, while the number of large whales are able to dive, such as sperm whales can dive 900 to 1134 meters. The formation of fin whales forelimbs, hind limbs completely degraded into a tail fin tail, the head of the upper nostril. Particularly noteworthy is the blue whale. It is the largest animal existing in the world, up to 30 meters in length and weighs 180 tons. Whales were identified as predators. Distribution of their food species to the large fish from a wide range of microorganisms. All mammals, including whales need to sleep, but the whales stay awake to breathe and can make them sleep in a brain hemisphere. So whales are never able to get the required sleep sleep. Whale about a day "sleep" 8 hours. Male sperm whales use the vas deferens into the female body. Complete the fertilization process, sperm and eggs in the female body with whales. Students usually a mother whale calf. Pregnancy basically about a year. Some breast-feeding baby whale may have to one year, raising longer-term, and some whale after birth, and even his mother several years before weaning. Living environment where they will encounter shark predation, so the mother will be established between the very strong relationship. Some whales, late maturity, about to be seven to ten years. Reproductive organs in the swimming whale to avoid resistance and retracted the body. 1 nipple mother whale, the contraction of the muscles around the breast by milk pushed the whale population to feed, Aberdeen cub. Whale's life is about 60 to 70 years. 【Subject】 Cetacea contains about eighty species of large marine life in the placental mammals. Whales are cetaceans, including dolphins whale and small whales. "Whale" itself is vague definitions can contain all the whales, some large, or belonging to a particular Section of whales. But the killer whales and pilot whales belong to dolphins (delphinidae). Cetaceans can be divided into two subheadings: mysticeti - baleen whales - and odontoceti - toothed whales. Extant species of baleen whales can be divided into sub-orders, and toothed whale suborder. Baleen whales suborder mysticeti Baleen whales include the world's largest living animal species. 3 families, 10 species are marine habitat. Whale Branch balaenidae such as: black right whale (black real whale) eubalaena glacialis, Southern Right Whale eubalaena australis, bowhead whales (whale arched) balaena mysticetus, small whales caperea marginata, right whale (Note : Some subjects were divided into small whale neobalaenidae) Section eschrichtiidae such as gray whales: gray whale eschrichtius robustus Baleen whales Division balaenopteridae such as: the blue whale (blue Wen whale, razorback) balaenoptera musculus, minke whales (small Wen whales) balaenoptera acutorostrata, humpback whales (humpback whales and large fin whales) megaptera novaeangliae, fin whale fin whale, a large baleen whales ( Wen whales), Brandt whale (anchovy whale) bryde's whale, whales, small Brandt balaenoptera edeni, sei whales sei whale Great size, the smallest species are also more than 6 meters in length. Mouth without teeth. Each side has the upper 150 to 400 horny baleen. Whalebone color, number and shape varies by species, is an important basis for classification. 2 external nostrils, located in the head. The first great, and some kinds of body length of up to 1 / 3. Only 1 to 2 ribs connected with the small sternum, no collarbone, 4 refers to the general flippers. With the cecum. They use the baleen to filter plankton from sea water. Krill and cephalopods as food, and some also eat small fish and benthic shellfish. Toothed whale suborder odontoceti Toothed whales born only a few types of fresh water, most are produced in the ocean. A total of more than 80 species including 7 families. (Note: The toothed whale suborder scoring subjects have some different views can be roughly divided into dolphins, beaked whales and sperm whales are great differences in the three groups, each group is divided up to Division One.) Freshwater puffer fish, also known as dolphin Section Division platanistidae. Such as: the baiji (white grouper dolphin) lipotes vexillifer, India puffer platanista indi, Platanistidae platanista gangetica, Boto inia geoffrensis, Madeira puffer inia boliviensis, La Plata dolphins pontoporia blainvillei. Dolphin Division delphinidae such as: dolphin delphinus delphis, short-beaked dolphins delphinus delphis linnaeus, long-beaked dolphin delphinus capensis gray, bottlenose dolphins tursiops truncatus, Amazon dolphins sotalia fluviatilis, orcas (killer whales, killer whales) orcinus orca , dolphin, dolphins, pilot whales (pilot whales, black round whale) globicephala melaena, big kiss pilot whales, pilot whales long limbs, short limbs pilot whales, melon head whales, killer whales, the Arctic, false killer whales pseudorca crassidens, Night at the killer whale. (Note: some pilot whales are divided into Division globiphlidae) Porpoises Division phocaenidae such as: finless porpoise neophocaena phocaenoides Narwhal Division monodontidae such as: narwhal (unicorn, corner whale) monodon monoceros, the white whale delphinapterus leucas, (Note: Sometimes the Irrawaddy dolphin (short dolphin) orcaella brevirostris also included in this Section.) Section hyperoodontidae beaked whales such as: long-beaked whale mesoplodon densirostris Brandt Section phy_set_eridae such as sperm whales: sperm whales phy_set_er catodon Pygmy sperm whales Division kogiidae such as: small sperm whales kogia breviceps, Japanese sperm whales kogiasimus Body sizes. Mouth with teeth, with only one external nostril. 5 refers to the general flippers. In addition to Platanistidae, but no cecum. This animal has a unique perception of the environment through echolocation ability. Mainly on squid, squid, crustaceans, fish for food. 】 【Economic value China's abundant whales, whaling has a long history. Economic value of large, edible meat, skin can be leather, spermaceti oil can be refined industrial oil and fat can be produced machine oil, soap, candles, bone can be made of bone, organs can be used for vitamin preparations. 】 【Protection Since a large number of environmental degradation and human hunting, whale members, especially members of the economic value of large widely hunted high, and many whales are endangered. International Whaling Commission (iwc) is responsible for the management of whaling and whale protection of international organizations. Commercial whaling in the lead after the sharp drop in the number of whales, iwc decided to take action to protect whales. Including a temporary ban from the 1986 commercial whaling in 1979 and 1994 respectively, established the Indian Ocean and Southern Ocean whale whales protected area protected areas. However, since 1986, as Japan, Norway, the resolution advantage of the loopholes iwc, the name of "scientific whaling" on the cover has killed more than 25,000 whales. Current whaling countries, Norway, Iceland and Japan, and Siberia, Alaska and northern Canada, a number of indigenous tribes.
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Cetacea (fossil)
jing mu (huashi) Cetacea (fossil) Whales (Cetacea) is divided into three sub-orders, of which the ancient whale suborder (Ar-chaeoceti) are all fossils, no extant species. Ancient whale suborder from the Eocene and Oligocene toothed whale armed Branch (Branch Whale ancient lizards, Basilosauridae), spear toothed whales Branch (Dorudontidea) and the original Whale Branch (Protocetidae) 3 Section. Most scholars believe that ancient vertebrates, with the beast of ancient whales Branch (Mesonychidae) a closer relationship. As in recent years, the ankle in the animal subjects included in the program, therefore, is generally believed that cetaceans originated in the ankle section of class. The earliest fossils of ancient whales found in North Africa and North America in the Eocene strata. In recent years, a number of ancient vertebrate scientists in Pakistan and India in the Eocene marine sediments, also found fossils of ancient whales. Baleen whales suborder (Mysticeti) is the vertebrate body is greatest. Is to be a primitive whale with teeth of whales evolved. Whale first appeared to be in the early Oligocene. In this suborder includes four sections: whales, animal subjects (Cetotheridae), began the Oligocene, Miocene very busy, some species have been living the late Pliocene; □ Whale Branch (Baleanopte-ridae), the earliest in the late Miocene, Pliocene and Pleistocene very prosperous, had been living to the modern; Whale Branch (Baleanidae), first appeared in the early Miocene, Pliocene, when the very prosperous, had been living to modern; Gray Whale Branch (Eschrichtidae or Rhachianectidae), all of the modern species. Toothed whale suborder (Odontoceti) is a more primitive toothed whales. This suborder is the most numerous species of whales in a suborder, including the majority of living whales. Toothed whale first appeared in the late Eocene, Miocene, the most prosperous time. China, except Tibet, Taiwan, the lack of Cenozoic marine sedimentary strata. Whale fossil found in small, coastal areas in Taiwan and sporadic late Cenozoic strata found. Early Tertiary strata in the Guangxi white dolphin has been found fossils. (Wang Jingwen)
Mysticeti