Whale Essay Research Paper Whale weighs as — страница 2

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estuarine forms. The remaining three families are the sperm whales (Physeteridae), the beaked whales and bottlenosed whales (Ziphiidae), and the white whales and narwhal (Monodontidae). Evolution Recent studies based on genetic sequences have confirmed that all cetaceans were derived from a single ancestral stock and are closely related to the hoofed mammals in the order Artiodactyla, made up of the even-toed mammals, such as cattle, deer, and camels. Nevertheless, the evolutionary origin of whales remains controversial among zoologists. The oldest fossils clearly recognizable as primitive whales were discovered in the Eocene epoch excavation layer of sites in Nigeria and Egypt. These early forms are placed in an extinct suborder (Archaeoceti) known as zeuglodonts. Whether they

are the ancestors of either modern suborder is a matter of conjecture. The largest archaeocete was Basiolsaurus, a whale from the late Eocene epoch that reached a length of almost 70 feet (20 meters). History of Whaling Archaeological evidence suggests that primitive whaling, by Inuit and others in the North Atlantic and North Pacific, was practiced by 3000 BC and has continued in remote cultures to the present. The primitive quarry were small, easily beached whales or larger specimens that came close to shore during seasonal migrations from polar feeding grounds to breed in sheltered bays. The Japanese used nets, and the Aleuts used poisoned spears. The Inuit successfully hunted large whales from skin boats, employing toggle-headed harpoons attached by hide ropes to inflated

sealskin boats. In Europe, the Nordic people hunted small whales, and Icelandic laws dealt with whaling in the 13th century. Conclusion In 1946 the International Whaling Commission (IWC) was established to set up the guidelines followed by whaling nations today. The sizes, kinds, locations, and seasons of catches are controlled. However, strong international politics came into play, and some nations steadfastly voted against, or even ignored, restrictions that were not economically advantageous. The limitations were passed almost too late for the blue whale, which had already declined to dangerously low numbers in all oceans. The once large populations of blue whales in the eastern North Atlantic were almost brought to extinction. Today, fewer than 500, and possibly as few as

100, are found there. In 1971 the United States declared all commercially exploited whales endangered species and made it illegal to import any whale products. The United States lists the blue, bowhead, finback, gray, humpback, right, sei, and sperm whales as endangered species. Therefore, we should take goof care of whale. Works Cited Cousteau, Jacques, and Paccalet, Yves. Whales (W.H. Allen, 1998). Tinker, S.W. Whales of the World (Bess Press, 1997). Day, David. The Whale War (Sierra Club Books, 1997).