Sharks and their relatives were the first vertebrate predators, and their prowess, honed over millions of years of evolution, allows them to hunt as top predators and keep ecosystems in balance.īut sharks are in trouble around the world. Wherever they live, sharks play an important role in ocean ecosystems-especially the larger species that are more “scary” to people. They are found in just about every kind of ocean habitat, including the deep sea, open ocean, coral reefs, and under the Arctic ice. They come in a variety of colors (including bubble gum pink), and some feed on tiny plankton while others prefer larger fish and squids. They range in size from the length of a human hand to more than 39 feet (12 meters) long half of all shark species are less than one meter (or about 3 feet) long. That generalization does sharks a huge disservice, as they have far more variety than that. Yet when most people think of these cartilaginous fish, a single image comes to mind: a large, sharp-toothed and scary beast. There are more than 500 species of sharks swimming in the world’s ocean.
