Mammals Like Dolphins Dominating Entire Aquatic Environment
Mammals are a group of animals with special combination of characteristics that separates them from all other group of animals. Their warm blooded nature helps them to survive in all parts of the world by maintaining a constant temperature internally. If the outside temperature exceeds a limit, their body will emit this excess heat outside, in the form of sweat. If it is so cold outside, the body will keep them warm. Thus a constant temperature for survival is present throughout the lifetime. Most mammals have hair on their body. At the same time there are some without a single hair. Mammals like dolphins come under that category. Marine mammals are those that spend complete or partial part of their lifetime in water bodies. They have almost similar characteristics of land living mammals. Their blood is mostly cold in nature. To keep their body warm, they have a thick layer of fat known as blubber. Marine mammals have the ability to travel through swimming. The presence of stream lined bodies is the main reason for such fast swimming.
Most of such marine mammals stay under water for a long time but they come to the surface for breathing. They store more amount of oxygen in their body muscles and blood, so they rarely come to the surface. There are five marine mammal categories. They are cetaceans, pinnipeds, polar bears, sea otters and sirenians. Seals and walruses come under pinnipeds. Mammals like dolphins and whales come in cetacean category. There are certain confusion regarding the question that, dolphins are mammals or fishes? The answer is mammals. Unlike fish, mammals like dolphins will breathe air through lungs and not through gills. They won’t store much oxygen inside their body. But they come to water surface to breathe. Dolphins give birth to their young ones and feed them. They have tiny amount of hair on their body.