When people think of sharks the classic image that comes to mind will most likely be that of the Great White, as made famous by the movie Jaws and numerous media reports of shark attacks on divers and fishing boats. However this is a misleading idea since sharks come in many different shapes and sizes. They live in a variety of different places, behave in a variety of different ways, and even eat a variety of different things, as this article will show.

While there are differences between the shark species, there are also many things that they have in common. For example, in order to be able to swim easily and not sink, sharks have very lightweight and flexible bones made of cartilage, the same material that makes up our noses. Because cartilage is such a lightweight material the sharks also have tesserae, which are reinforced plates of hard calcium salts for protection. They continuously shed their teeth in order to ensure that they never wear down and become useless, something particularly important when you are a top predator in the seas! Some species of sharks are known to shed nearly 1000 teeth every year. Both the upper and lower jaws of the shark’s mouth can move independently of each other, and in order to breathe under water sharks have at least five pairs of vertical gill slits which are mounted on the side of their head. Lastly, all shark species are the product of around 400 million years of evolution, though they haven’t had to evolve much in the last 150 million years.

In order to better illustrate the differences and similarities between different shark species, this article will now look in depth at a few of those species. The first is the Great White Shark, Latin name Carcharadon carcharias, which is one of the most fearsome predators in the sea. Aside from its notoriety gained from movies and the media, the Great White Shark is also identifiable because it has distinctive colouring, black eyes, and ferocious teeth and jaws. It can be found in most of the seas and oceans of the world because it is able to keep its body temperature higher than that of its surroundings, which means that it is able to live in very cold waters, as well as in the more temperate seas that other shark species favour. The Great White is a very curious species of shark and likes to explore new objects in its surroundings by biting them. It is this behaviour that has brought them to the attention of humans, since Great Whites have often bitten humans as part of this exploration and learning process. The main food of the Great White is fish and other species of sharks, as well as seals, dolphins, and sea birds.

The largest shark, and indeed the largest fish currently alive, is the Whale Shark, Latin name Rhincodon typus. Due to its large size the Whale Shark is a dramatic sight in the warm and tropical seas which it inhabits. But despite their huge size Whale Sharks mostly feed on tiny zooplankton, though they do also feed on shoals of small fish and squid. The most distinctive feature of this shark is its huge front set mouth which it uses to suck up its prey before filtering it in their stomach. Whale Sharks differ from other shark species in that they are migratory creatures and travel around the oceans in order to take advantage of seasonal events, such as plankton booms and coral spawning.

The Basking Shark, Latin name Catorhinus maximus, is the second largest shark in the seas. Unlike the Whale Shark, the Basking Shark lives solely on plankton, typically going for invertebrate larvae, small crustaceans and fish eggs. The image which most often comes to mind when people think of the Basking Shark is of it swimming around with its mouth wide open, something it does in order to sieve up the tiny plankton from the water as they swim. Basking sharks are a very docile breed of shark and are very tolerant of humans making them a favourite of eco-tourists. Their tolerance of humans, combined with their large size, has also led them to be severely hunted, and they are now protected under law in most countries to ensure the continuation of their species.

Another well known, and easily recognisable species of shark, is the Hammerhead Shark, Sphyrna zygaena, which is so named because of its hammer shaped head. There are about 10 species of Hammerhead Shark worldwide, and they can grow up to 6 metres in length and, like the Great White shark, have been known to attack humans. This species feeds on fish, crustaceans and cephalopods (marine molluscs), and are found in temperate waters in areas like southern Canada, Chile and New Zealand.

Away from these very well known species of sharks, some lesser known species also inhabit the seas and oceans. One of these is the Megamouth Shark, Latin name Megachasma pelagios, which was discovered in the 1970s. Since then only 22 specimens have even been described, and as a result there is a lot about the life of this shark that is unknown. They are, however, known to eat plankton, small shrimps and jellyfish, and are able to grow to very large sizes like the other two plankton eaters, the Nurse and Whale sharks mentioned above. Its most distinguishing feature is its large and oddly shaped mouth which lent the Megamouth Shark its name.

Lastly, a second lesser known, but very common, species of shark is the Kitefin shark, Latin name Dalatias licha. A short blunt snouted shark of moderate size, the Kitefin Shark is the smallest shark featured in this article, and is found all around the world commonly below a depth 200m, though they are known to venture to depths of 1800m. This is a solitary species of shark with are a grey to dark brown colour, and thick papillose lips which their most distinguishing feature. They feed on fishes, small sharks, cephalopods and crabs.