Sharks have been around longer than dinosaurs but are often misunderstood as terrifying monsters. Here’s 39 interesting facts about sharks to help you appreciate them better…
Sharks have survived 5 mass extinctions including the one that killed the dinosaurs.
Today there are more than 450 known species of sharks living in our oceans.
Sadly, nearly one in four of these species are currently threatened with extinction due to human activities like overfishing and shark finning.
Sharks boost local economies through ecotourism. Over the last several decades, public fascination with sharks has developed into a thriving ecotourism industry in places such as the Bahamas, South Africa, and the Galápagos Islands.
Humans kill up to 100 million sharks per year.
Sharks are killed to supply the demand for their fins, which are made into soup and eaten as a status symbol.
You’ve probably eaten shark if you’ve been traveling in Europe and are a fan of fish and chips. Spiny dogfish sharks are popular in the international market.
Shark anatomy has inspired smart design such as watercraft, cars, and water turbines.
Some researchers are now trying to make artificial shark skin that would reduce friction drag and prevent the accumulation of algae and barnacles in the water and even prevent bacterial growth when applied to hospital surfaces.
The world’s biggest shark, the whale shark, can grow as long as 40 feet. Each of the whale shark’s spot patterns are as unique as a human fingerprint.
While whale sharks aren’t as popularized in media as the jagged-toothed great whites, they do have a considerable impact on coastal economies around the world. As very docile fish, whale sharks attract large amounts of dive tourism, amounting to nearly $50 million annually.
Whale sharks have been known to give a ride to hitchhiking swimmers, and cruise through the water atop them.
The megamouth shark was only discovered in 1976, and fewer than 100 of these rare sharks have ever been seen. It grows to an average of 16 feet and siphons plankton out of the water to feed.
Even more recently was the discovery of the pocket shark, a 5-inch shark found in the Gulf of Mexico. It glows under the water to attract prey.
Tiger sharks eat pretty much anything they can get their jaws around. Among the odd object found in their stomach are license plates, video cameras, dog leashes, and bags of money, birth control pills, and other sharks.
Hammerhead sharks’ eyes are on the sides of their heads, so they have nearly a 360-degree sightline. Their panoramic view of the undersea world is inhibited by two blind spots, one in front of the snout and the other directly behind the head.
Sharks’ skeletons are made of pure cartilage and muscle. Since it’s half the density of bone, this makes the shark lighter and more flexible.
Shark teeth are resistant to cavities. They’re covered in fluoride, an enamel known as fluorapatite. This material is resistant to acid created by bacteria.
Sharks also go through several sets of teeth in their lifetimes, shedding and growing new teeth periodically.
Not all sharks have the same type of teeth, mako sharks have very pointed teeth; while white sharks have triangular, serrated teeth – all leaving a unique mark on their prey. The average shark has 40-45 teeth in up to 7 rows, which they tend to lose regularly and can go through an astonishing 30,000 teeth in their lifetime!
Because sharks are constantly losing and replacing teeth, experts say there are trillions of teeth sprinkled on the ocean floor.
Sharks can freely move both their upper and lower jaws.
Sharks exhibit great diversity in their reproductive modes. There are oviparous (egg-laying) species and viviparous (live-bearing) species.
Female sharks can be impregnated by multiple partners at once.
Through a process that has been observed in many animals, sharks can also clone themselves through parthenogenesis, a type of external fertilization. This has been seen in female sharks being kept in captivity.
Sharks are so tough, their embryos are known to attack one another.
Partly because they need to carry shark babies, females tend to be larger in most shark species.
Humans are a far greater danger to sharks than they are to us. There are fewer than 200 shark-human interactions globally every single year.
Great White shark
Sharks have a variety of feeding habits. Many species of sharks are filter feeders that eat small marine life, such as clams, and many are bottom feeders who use suction to gather food. Only some species of sharks are hunters that attack seals, dolphins, and other large sea creatures.
Sharks have the same five senses as human beings plus one more. Sharks have an organ in their snouts, ampullae of Lorenzini that allows them to sense electrical fields in the water emitted by other fish and marine life.
Sharks don’t sleep like humans. Since some species have to continue swimming in order to breathe, instead of falling into a deep sleep, sharks remain semi-conscious.
Most sharks have to keep swimming to pump water over their gills. However some bottom dwelling sharks such as angel sharks and nurse sharks have an extra respiratory organ called ‘sharks spiracle’ which supplies oxygen directly to the sharks eyes and brain – so they are able to breathe while at rest on the seafloor.
Scientists have been using a new method of determining shark age by using a radiocarbon timestamp found in the vertebrae of sharks left over from nuclear bomb testing in the 1950s and 1960s.
While sharks live in all of the world’s oceans, a few species are also known to inhabit freshwater lakes and rivers.
Despite what you may have seen in Walt Disney‘s “Finding Nemo,” sharks definitely can’t talk, even to other fish. Sharks have no vocal cords; therefore, they make no vocal sounds whatsoever. Instead, they communicate through body language.
Great White shark
Large sharks have a bite twice as powerful as that of a lion, and can exert a pressure of up to 40,000 pounds per square inch.
Sharks can only swim forward because their fins are stiff and cannot be controlled by muscles.
They have an amazing sense of hearing. They can hear prey up to 3000 feet away.
Sharks have the thickest skin of any animal species – some sharks even have skin that is 6 inches thick!
Do you know any interesting or fun facts about sharks that we’ve missed? Share them here in the comments section below!