‘100 Facts You should Know: Whales and Dolphins’ (I)
‘100 Facts You should Know: Whales and Dolphins’ by Steve Parker
1. Whales, dolphins and porpoises are a group of marine animals known as cetaceans. They have warm blood and breathe air. Almost all kinds live in the sea, apart from a few species of dolphin that live in freshwater rivers and lakes.
2. The blue whale is the largest animal. It can grow up to 30m in length and reaches up to 150 tons in weight.
3. The sperm whale is the biggest predator on Earth. It grows up to 20m in length and 50 tons in weight.
4. Whales breathe air, just like humans. They must hold their breath as they dive underwater to feed. A few of them can stay underwater for more than one hour.
5. The whale group is divided into two main types: baleen whales and toothed whales.
6. Baleen whales are often called great whales. The sei whale, for example, is about 16m long. Baleen whales catch food with long strips in their mouths called baleen, or whalebone.
7. Toothed whales catch prey with their sharp teeth. This subgroup include sperm whales, beaked whales and pilot whales. Beluga, or white whale, is one of the noisiest whales, making clicks, squeaks and trills.
8. Most mammals have hair or fur. Whales, dolphins, and porpoises are unusual because they have smooth, hairless skin to make them streamlined. Only a few hairs, mainly bristles, can be found around the eyes, nose and mouth.
