Eared Seals History

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There are two points of view of the evolutionary history of the seal, the first view is the eared seals came from a bear like ancestor and the earless seal came from a otter like ancestor due to some similar function of the internal and external organs . The second view is that seals came from the monophyletic group and in a certain point they share a common ancestor. There was an animal called the enaliarctos and it was the last common ancestor of the seals. This animals spent more time on land than in the water than any other pinnipeds. The enaliarctos swim in the water while using both the foreflippers and hind flippers. In modern seals they do not use the foreflippers, they use their tails for steering in the water and the hind flippers …show more content…

as otariidae group which contains fur seals and eared seals. The other group is phocidae which contains true seals. Their class within the animal kingdom is mammalia and their is 35 species of seals. . Their order is carnivores and their phylum is chordata. True seals are also known as earless seals because they lack of external parts of the ears. They still have functional ears but its inner and not external like other seals. Thier hairs are short and have a dense undercoat, they can have a variety of colors. For example they come in light gray with silver dark spots, black , red , dark gray, or brown with white rings. They are mostly covered in spots and it comes in all sizes big or small. When they are pups their colors are usually in solid light gray, black, red , dark gray, or brown. True seals habitats are Northeastern Atlantic ocean , Western Atlantic ocean, Arctic ocean, Eastern pacific , and western pacific. Eared seals habitats are Northern Pacific between Asia and North America. They are also found off the coast of Southwestern Africa, Southern Austria , South America , and …show more content…

The PNS contains somatic nervous system and the autonomic nervous system. The autonomic nervous system controls the function of internal organs like your heart, stomach, cardiac muscle, and your glands. The autonomic nervous system has an effect on the organs, muscles, and glands are all done voluntary. The autonomic nervous system can change the body temperture, send extra blood to a particular area, slow your heartbeat, and pull the stomach secretion. The somatic nervous system is made up of sensory organs and nerves that connects to the skin, also that connects to all the skeleton muscles. The Somatic nervous system has two neutrons. Those two neutrons are sensory neurons and motor neurons. The sensory neurons job is to carry information to the central nervous system. The motor neurons job is to carry information from the brain and spinal cord to the muscle fibers throughout the