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Are you looking for facts about sharks? In recent decades, researchers have committed to learning about and studying about sharks in more depth, which has yielded some fascinating and fun facts and has cleared up many myths.

Sharks have long been feared and even worshipped by mankind. However, for centuries, little was known about these fascinating creatures. We present you the most interesting and fun facts about sharks.

Shark Fact 1

The smallest shark is the Dwarf Shark, which is approximately the length of the average man's hand.

Shark Fact 2

The largest shark is the Whale Shark, which is about the length of a bus.

Shark Fact 3

Every year, sharks attack approximately 100 people, of which about 10 result in a human fatality. On the other hand, human beings kill 10's of million's of sharks every year for their skin, fins, meat and liver oil. This would imply that humans are far more dangerous than sharks.

Shark Fact 4

There are approximately 350 different species of known sharks.

Shark Fact 5

A large meal may last the shark up to three months without it having to eat again.

Shark Fact 6

Sharks are at the top of the underwater food chain.

Shark Fact 7

More people are killed every year by bee stings, lightening or soda machines falling on them than by sharks.

Shark Fact 8

Sharks attack more men than women.

Shark Fact 9

The Bull Shark can live in fresh water or sea water.

Shark Fact 10

Sharks can hear a fish swimming over one mile away, and can smell one drop of blood in a million drops of water.

Shark Fact 11

The upper and lower jaws of the shark are able to move, unlike humans and most other animals.

Shark Fact 12

By counting the rings on the shark's vertebrae, one is able to gauge the age of the animal.

Shark Fact 13

A shark may lose and grow up to 30 000 teeth in its lifetime.

Shark Fact 14

Two-thirds of the brain of a shark is dedicated to its sense of smell.

Shark Fact 15

Oil in the liver is what keeps the shark from sinking as its density is lower than that of the surrounding water.

Shark Fact 16

In Fiji and the Solomon Islands, people are not allowed to eat the meat of the shark. These animals are believed to possess mighty spirits of dead ancestors.

Shark Fact 17

Even hundreds of years ago, people used shark teeth for the creation of weapons and tools.

Shark Fact 18

Swimmers have a one in 300 million chance of being killed by a shark.

Shark Fact 19

The Oceanic White-tipped Shark is the most dangerous living shark in terms of human attacks as it does not fear divers or swimmers.

Shark Fact 20

The Portuguese Shark can dive more than 1.5 miles, or 2.7 kilometres, below the surface of the ocean.

Shark Fact 21

Females are usually larger than males and have thicker skin to withstand the bites of males wanting to mate with them.

Shark Fact 22

Shark pups begin their hunting and killing before they are even born by consuming their weaker siblings inside their mother's oviduct.

Shark Fact 23

Sharks can detect the electrical impulse emitted by a standard AA battery one mile away.

Shark Fact 24

There are approximately 75 species of shark on the endangered list.

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Are you looking for facts about sharks? In recent decades, researchers have committed to learning about and studying about sharks in more depth, which has yielded some fascinating and fun facts and has cleared up many myths. Sharks have long been feared and even worshipped by mankind.

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Sharks use their gills to filter oxygen from the water. They are a special type of fish known as "elasmobranchs", which translates into fish made of cartilaginous tissues- the clear gristly stuff that your ears and nose tip are made of. This category also includes rays, sawfish, and skates. Their cartilaginous skeletons are much lighter than true bone and their large livers are full of low-density oils, both helping them to be buoyant.

Even though sharks don't have bones, they still can fossilize. As most sharks age, they deposit calcium salts in their skeletal cartilage to strengthen it. The dried jaws of a shark appear and feel heavy and solid; much like bone. These same minerals allow most shark skeletal systems to fossilize quite nicely. The teeth have enamel so they show up in the fossil record too.

Most sharks can see well in dark lighted areas, have fantastic night vision, and can see colors. The back of sharks' eyeballs have a reflective layer of tissue called a tapetum. This helps sharks see extremely well with little light.

Sharks have small black spots near the nose, eyes, and mouth. These spots are the ampullae of Lorenzini - special electroreceptor organs that allow the shark to sense electromagnetic fields and temperature shifts in the ocean.

4. Shark skin feels similar to sandpaper.

Shark skin feels exactly like sandpaper because it is made up of tiny teeth-like structures called placoid scales, also known as dermal denticles. These scales point towards the tail and help reduce friction from surrounding water when the shark swims.

When you flip a shark upside down they go into a trance-like state called tonic immobility. This is the reason why you often see sawfish flipped over when our scientists are working on them in the water.

Based on fossil scales found in Australia and the United States, scientists hypothesize sharks first appeared in the ocean around 455 million years ago.

Vertebrae contain concentric pairs of opaque and translucent bands. Band pairs are counted like rings on a tree and then scientists assign an age to the shark based on the count. Thus, if the vertebrae has 10 band pairs, it is assumed to be 10 years old. Recent studies, however, have shown that this assumption is not always correct. Researchers must therefore study each species and size class to determine how often the band pairs are deposited because the deposition rate may change over time. Determining the actual rate that the bands are deposited is called "validation".

The blue shark displays a brilliant blue color on the upper portion of its body and is normally snowy white beneath. The mako and porbeagle sharks also exhibit a blue coloration, but it is not nearly as brilliant as that of a blue shark. In life, most sharks are brown, olive, or grayish.

Whale sharks are the biggest fish in the ocean. They can grow to 12.2 meters and weigh as much as 40 tons by some estimates! Basking sharks are the world's second largest fish, growing as long as 32 feet and weighing more than five tons.

A shark's spiracle is located just behind the eyes which supplies oxygen directly to the shark's eyes and brain. Bottom dwelling sharks, like angel sharks and nurse sharks, use this extra respiratory organ to breathe while at rest on the seafloor. It is also used for respiration when the shark's mouth is used for eating.

Mako sharks have very pointed teeth, while white sharks have triangular, serrated teeth. Each leave a unique, tell-tale mark on their prey. A sandbar shark will have around 35,000 teeth over the course of its lifetime!

Sharks exhibit a great diversity in their reproductive modes. There are oviparous (egg-laying) species and viviparous (live-bearing) species. Oviparous species lay eggs that develop and hatch outside the mother's body with no parental care after the eggs are laid.

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1. Sharks do not have bones. Sharks use their gills to filter oxygen from the water. They are a special type of fish known as "elasmobranchs", which translates into fish made of cartilaginous tissues-the clear gristly stuff that your ears and nose tip are made of. This category also includes rays, sawfish, and skates.

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By Justin Kovach

Sharks make the news for all the wrong reasons, but there are many other points of interest about this majestic fish that deserve consideration. So let's sink our teeth into some fun facts about this celebrated deep-sea predator:

1. There are over 500 species of shark varying in size, shape, environment and diet. While some are small, others, like the whale shark, can grow up to 40 feet long.

2. Sharks live in every part of the ocean, and some can survive in fresh water. One of the most interesting in appearance is the Mitsukurina Owstoni, or goblin shark, so called for its facial features. It is the oldest living species among lamniform sharks, dating back to about 125 million years ago.

3. The first sharks are believed to have evolved about 400-455 million years ago. But it may have been even longer ago because unlike other fish, sharks have a flexible cartilage skeleton that is rarely preserved the same way typical fish bones are. Although they are considered vertebrates, they have no bones. Their skeletons are made of cartilage, making them cartilaginous fish.

4. All sharks have several rows of teeth, which they lose regularly, only to be replaced by new ones. Shark teeth from millions of years ago have been preserved at the bottom of the ocean. Sandy sediment that covered the shark teeth protected them from oxygen and bacteria, allowing them to fossilize over the course of 10,000 years.

5. Sharks eat fish, crustaceans, mollusks, plankton, marine mammals, and even other sharks. Their strong sense of smell allows them to detect blood in the water miles away.

6. Most sharks are cold-blooded. But some sharks, such as the great white shark, are warm-blooded, which enables them to grow and swim faster. But they need to eat up to 10 times more than their cold-blooded cousins.

7. Some etymologists believe the word shark derives from earlier German and Dutch words for a shifty character, while others suggest it comes from Xoc (pronounced "shoke"), which means "great fish" in the Mayan language of Yucatec.

8. The largest known species was the megalodon, which grew longer than 50 feet. But you're safe from that behemoth, as it went extinct around 2.6 million years ago.

9. The notion that sharks can't develop cancer is a myth. They do, as we've known since at least 1908. Researchers in Australia found a tumor protruding from the mouth of a great white shark in 2013.

10. Humans perceive sharks as a threat, yet the fishing industry kills up to 100 million sharks a year just for their dorsal fins. The slaughtered far outnumber the few shark attacks that are reported each year. So even though they can be aggressive, remember that when you're swimming in the ocean, you're swimming in their home. It is best to be not only cautious but also appreciative of this diverse and ancient species that is an integral part of a vast and magnificent ecosystem.

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By Justin Kovach Sharks make the news for all the wrong reasons, but there are many other points of interest about this majestic fish that deserve consideration. So let's sink our teeth into some fun facts about this celebrated deep-sea predator: There are over 500 species of shark varying in size, shape, environment and diet.

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shark, any of numerous species of cartilaginous fishes of predatory habit that constitute the order Selachii (class Chondrichthyes).

Sharks, together with rays and skates, make up the subclass Elasmobranchii of the Chondrichthyes. Sharks differ from other elasmobranchs, however, and resemble ordinary fishes, in the fusiform shape of their body and in the location of their gill clefts on each side of the head. Though there are exceptions, sharks typically have a tough skin that is dull gray in colour and is roughened by toothlike scales. They also usually have a muscular, asymmetrical, upturned tail; pointed fins; and a pointed snout extending forward and over a crescentic mouth set with sharp triangular teeth. Sharks have no swim bladder and must swim perpetually to keep from sinking to the bottom.

There are more than 400 living species of sharks, taxonomically grouped into 14-30 families, according to different authorities. Several larger species can be dangerous to humans. The largest predatory sharks, such as the white shark and tiger shark, are often considered to be the apex predators (meaning without a natural predator or enemy) of their marine environments. Numerous sharks are fished commercially. However, overfishing in the late 20th and early 21st centuries substantially reduced the populations of some shark species.

Description and habits

Shark species are nondescript in colour, varying from gray to cream, brown, yellow, slate, or blue and often patterned with spots, bands, marblings, or protuberances. The oddest-looking sharks are the hammerheads ( Sphyrna), whose heads resemble double-headed hammers and have an eye on each stalk, and the wobbegongs (family Orectolobidae), whose skin flaps and protective coloration closely resemble the seafloor. The vernacular of shark names indicate colours in living species, such as the blue ( Prionace glauca), the white ( Carcharodon carcharias; also known as the great white shark), and the lemon ( Negaprion brevirostris) shark.

The whale shark ( Rhincodon typus) and the basking shark ( Cetorhinus maximus), both of which may weigh several tons, are harmless giants that subsist on plankton strained from the sea through modified gill rakers. Whale sharks may grow up to 18 metres (59 feet) in length, whereas basking sharks may reach 14 metres (46 feet) fully grown. All other sharks prey on smaller sharks, fish, squid, octopuses, shellfish, other invertebrates, and, in some species, trash. The largest among the more predatory species is the voracious 6-metre (20-foot) white shark, which attacks seals, dolphins, sea turtles, large fish, and occasionally people. The more sluggish Greenland shark ( Somniosus microcephalus) of cold deep waters feeds on seals, large fish, and even swimming reindeer; they may also scavenge whale carcasses.

Normally, sharks feed on fish, often attacking in schools. Open-ocean species such as the mackerel ( Lamna), mako ( Isurus), and thresher ( Alopias) sharks frequently feed near the surface and are much sought after with rod and reel for sport. Beautifully streamlined and powerful swimmers, those open-ocean sharks are adept at feeding on fast tuna, marlin, and the like. Bottom-feeding species of sharks are stout, blunt-headed forms that tend to have more-sluggish habits. The shellfish eaters among them have coarse, pavementlike, crushing teeth.

Fertilization in sharks is internal. The male introduces sperm into the female by using special copulatory organs (claspers) derived from the pelvic fins. The young in many species hatch from eggs within the female and are born alive. Other species may lay eggs or nurture their young in the uterus with a placental attachment to the mother, like humans. Some species may even consume their siblings before they are born.

The origin of sharks is obscure, but their geologic record goes back at least to the Devonian Period (419.2 million to 358.9 million years ago). Fossil sharklike fish appeared in the Middle Devonian Epoch and became the dominant vertebrates of the Carboniferous Period (358.9 million to 298.9 million years ago). Modern sharks appeared in the Early Jurassic Epoch (201.3 million to 174.1 million years ago) and by the Cretaceous Period (145 million to 66 million years ago) had expanded into the present-day families. Overall, evolution has modified shark morphology very little except to improve their feeding and swimming mechanisms. Shark teeth are highly diagnostic of species, both fossil and modern.

Sharks' geographic ranges are not well known. Their extensive movements are related to reproductive or feeding activities or to seasonal environmental changes. Tagging returns from large sharks on the east coast of the United States indicate regular movements between New Jersey and Florida, and blue sharks have been recovered after crossing the southern Atlantic Ocean. A tagged spiny dogfish ( Squalus acanthias) was recovered after traveling about 1,600 km (1,000 miles) in 129 days. Advances in tracking technologies include the use of satellite tags that continuously beam a signal to orbiting satellites whenever the shark surfaces and in that manner reveal north-south movements, transoceanic movements, and roaming and migratory patterns that are beginning to be understood for many species.

Some members of the Carcharhinus genus-most notably the bull shark ( C. leucas)-enter fresh waters. Riverine sharks are small to medium-sized and are exceptionally voracious and bold.

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Shark, any of numerous species of cartilaginous fishes that make up the order Selachii (class Chondrichthyes). Most species have a tough skin that is dull gray in color and roughened by toothlike scales. The mouth contains sharp triangular teeth. Sharks lack a swim bladder and must swim to keep from sinking.