Dolphins are smaller, toothed whales which mostly live in salt water oceans but some Dolphins live in rivers too .There are two types of Dolphins - Oceanic Dolphins and River Dolphins.The word dolphin means the fish with womb , it originally comes from an ancient Greek word . Dolphins are mammals and they belong to the order Cetacea and are considered very wise intelligent and friendly.
Dolphins breathe air with their nose which is on the top of their head. They have soft and smooth skin with no scales. Dolphins are very social animals and they help each other to fight with their enemies like sharks and other predators. They swim in large group or herd. The large group of dolphins is called a pod or school.They communicate with each other by whistling and clicking.
The male dolphins take care of their young ones (calves) when the mother dolphin has to leave the babies in order to search the food.The male dolphins are called bulls and the female dolphins are called cows.
One very interesting fact about the dolphins is that they have two sides of the brain and when they sleep only one side of their brain sleeps while they keep the one side of brain awake. They also keep their one eye open while sleeping to watch out for their enemies. Sharks are dolphins' biggest enemies, they always are afraid of sharks.
Bottle nose dolphin (in the image above) is the most common and popular dolphin in the world.
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