A whale is a marine mammal in the order Cetacea, which also includes dolphins and porpoises. Technically, the term could be used to refer to any animal in this biological order, but by convention, it is reserved for particularly large representatives of the order. Whales can be found in all the oceans of the world, migrating to different regions for breeding and feeding, and the animals hold a popular mystique with humans, due to their impressive size and striking behaviors.
There are two basic types of whale. Toothed whales have massive jaws and teeth for eating a varied diet of marine animals. Baleen whales are filter feeders, eating plankton and other small organisms. Baleen resembles a comb, and is made from keratin, the same tough fiber which makes up human hair and nails. Both whale types have horizontal split flukes, or tails, and front flippers. In addition, a whale has a blowhole to breathe through at the top of its head.
Unlike most animals, a whale decides when it should breathe. Some whales are capable of remaining submerged for up to an hour before needing to resurface for fresh air. Whales expel water from the surface of their blowholes when they are preparing to breathe, leading to distinctive whale “spouts” which are used to spot whales. Each whale species has a distinctive spout, allowing people to determine what type of whale they are looking at.
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