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Lives of Whales and Dolphins
The Lives of Whales and Dolphins By Aaron Schwartz
Cetaceans are likely to have come from some predatory animals that are close to ancestors of dogs. But there is also an assumption that cetaceans came from insectivorous. But nevertheless it is known that they appeared about 70 million years ago, and now all their connections with land were lost long ago. Their adaptability to life in the sea is expressed much better than adaptability of all other water mammals.
The nature transformed cetaceans??forefeet into flippers, their hind legs disappeared at all. Their body looks like fish?™s one, but caudal fin is set horizontally, but not vertically as fish?™s fin.
Dolphins belong to a group of mammals called cetaceans. Modern cetaceans are divided into two subclasses: toothed and whiskered whales. The Dolphins are representatives of toothed whales.
But what are dolphins? Almost everyone knows the answer. These are the animals that teach people to live in harmony with each other, to love each other, to live in peace. They are really wonderful, beautiful, fascinating animals.
Looking at their eyes we can see their life, love and freedom! These feelings are not alien to dolphins, because like each of us they are mammals. Like all of us they have teeth, blood, heart, they nurse their little children and take care of them.
These magic creatures stagger by their kindness, intelligence, by their desire to communicate with people, be close to them. These animals are loved and adored in many countries through out the world by people of various cultures, nationalities and religion.
Let?™s speak about these wonderful animals - dolphins!
Natural history.
Dolphins are considered to be a specimen of the highest adaptation to marine elements. To demonstrate it let?™s describe dolphins itself. Dolphins vary greatly in their appearance, size and color.
Usually dolphins have long slender and very powerful bodies. Birth length of their body varies from 70-130 cm, their adult length - 190-390 cm. The biggest dolphin is the killer whale. Killer whale?™s length at birth 2.44 meters, and can reach over 6.1 meters long. Bottlenose dolphins are about 1.1 meters at birth and grow to 2.8 meters.
Dolphins??usual birth weight is about 5 ??30 kg, and their adult is in average 150 ??650 kg.
Color of dolphins??body is very variable. Some, for instance the killer whale, are strikingly white and black. Other ??like the false killer whale ??are only black. The color of the bottlenose dolphins has different shades of gray. Their body is of dark gray color with white and pink bellies.
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