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Seal PowerPoint Presentation

Seal

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Seal

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  1. Seal

  2. Classification Phocidae (pinnipeds) are earless seals with sleek-bodied and barrel-shaped. Their bodies are well adapted to the aquatic habitat where they spend most of their lives. Their limbs consist of short, wide, flat flippers. Earless seals also called true seals, or phocids, are the most diverse and widespread pinnipeds. They lack external ears, have more streamlined snouts, and are generally more aquatically adapted than otariids. They swim with efficient, undulating whole-body movements using their more-developed rear flippers. The swimming efficiency and an array of other physiological adaptations make them better built for deep and long diving and long distance migration. However these mammals are very clumsy on land, moving by wriggling their front flippers and abdominal muscles. The two back flippers form a tail-like structure which does not aid walking on land. True seals generally communicate by slapping the water and grunting rather than vocalizing. Fur seals have both blubber and a specially adapted fur coat, including outer guard hairs that repel water and a layer of insulating underfur. For this reason they were particularly prized by sealer. Pinnipeds use several strategies to conserve body heat while foraging in cold waters. Most primarily rely on a thick layer of blubber (fat) under their skin, which also provides buoyancy, hydrodynamic shape, and stores energy. Phocid lactation varies from four to 50 days. This reflects the fact that phocid feeding grounds tend to be far off shore, so lactation is associated with maternal fasting. To compensate for the short lactation period, the fat content of phocid milk (45–60% fat) is higher than in any other marine mammal species. After lactation, most females migrate to feeding grounds for intensive foraging to recoup energy reserves. Pinnipeds are carnivorous animals that feed on fish, shellfish, squid, penguins, and other marine creatures. Most are generalist feeders, but some specialize. For example, Ross seals and southern elephant seals mainly feed on squid. Crabeater seals eat mostly krill, and ringed seals almost exclusively consume crustaceans. http://en.wikipedia.org/wiki/Pinniped

  3. Seal phalanges 1. 2. 1.Carpals 2.Metatarsal 3. Proximal phalanges 4. Intermediate phalanges 5. Distal phalanges 3. 4. 5.