Whales And Dolphins

Whales

Whales are large, intelligent, aquatic mammals. They breathe air through blowhole into lungs (unlike fish who breathe using gills). Whales have sleek, streamlined bodies that move easilythrough the water. They are the only mammals, other than manatees (seacoast) that live their entire lives in the water, and the only mammals that have adapted to life in the open oceans
Like allammals:
* Whales breathe air into lungs,
* Whales have hair (although they have a lot less than land mammals, and have almost none as adults),
* Whales are warm-blooded (they maintain a highbody temperature),
* Whales have mammary glands with which they nourish their young,
* Whales have a four-chambered heart.Many cetaceans, especially baleen whales, migrate over very long distances each year. They travel, sometimes in groups (pods), fromcold-water feeding grounds to warm-water breeding grounds.
Cetaceans give birth to live young who are nourished with milk from their mothers - they don't lay eggs. Cetaceans breed seasonally, usually in warmtropical waters, and females usually have one calf every 1-3 years. The gestation times range from 9-18 months. Whale calves can swim at or soon after birth. Mother whales care for their young for anextended period of time, usually at least a year, feeding them milk and protecting them.
There are many species of whales that are in danger of going extinct. Most baleen whales (the huge whalestargeted by commercial whalers) are listed as endangered or protected species. Most other whale species are doing well and are not endangered.
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THE DOLPHINS
Dolphins are marine mammals closelyrelated to whales and porpoises. There are almost forty species of dolphin in 17 genera. They vary in size from 1.2 m (4 ft) and 40 kg (90 lb) (Maui's dolphin), up to 9.5 m (30 ft) and 10 tones (9.8...