SHARK GUARDIAN
TOP 100 SHARK FACTS
Shark fossil By James St. John
Raggie shark research
Shark history and evolution facts:
-
Sharks have prowled Earth’s oceans for over 400 million years, predating the dinosaurs by 200 million years.
-
Sharks have survived five major extinction events, including the one that wiped out the dinosaurs 65 million years ago.
-
Some species, like the Sevengill Cow shark, have remained virtually unchanged for more than 150–190 million years.
-
Early sharks looked very different, with strange body shapes, long spines, and no modern teeth.
-
Sharks have evolved into over 500 species today, each adapted to different ocean environments and roles.
Cladoselache shark
Raggie shark research
Prehistoric and extinct shark facts:
-
One of the earliest sharks, Cladoselache, lived over 400 million years ago and reached about 1.2 m in length.
-
During the Devonian period, at least 10 shark families evolved, giving rise to the diversity we see today.
-
Megalodon sharks became extinct around 1.2 million years ago.
-
The Carboniferous period is known as the “Golden Age of Sharks”, when they were the dominant predators of the seas.
-
Fossilized shark teeth are among the most common marine fossils, helping scientists trace shark evolution over millions of years.
Megalodon shark facts:
-
Megalodon was the one of the largest shark in history, growing up to 16 meters long. The Whale shark is the largest known shark.
-
Its massive teeth could reach over 18 cm (7 inches) – bigger than a human hand.
-
It preyed on whales, dolphins, and large fish, using powerful jaws to crush bones.
-
Megalodon lived between 23 and 1.2 million years ago, during the Miocene and Pliocene epochs.
-
Megalodon is extinct, and no evidence suggests it still exists today.
Sharks and the ocean facts:
-
Sharks keep ocean food chains in balance by controlling populations of other marine animals.
-
Healthy shark populations help protect coral reefs and seagrass beds by maintaining ecosystem balance.
-
Sharks often remove sick or weak animals, helping keep fish populations strong and healthy.
-
Sharks support biodiversity by regulating species below them in the food web, allowing many others to thrive.
-
Shark presence influences the behavior of prey, preventing overgrazing and helping habitats recover naturally.
Shark senses facts:
-
Smell: Sharks can detect a single drop of blood in water from hundreds of meters away.
-
Hearing: Sharks hear low-frequency sounds and can detect struggling prey from long distances.
-
Electroreception: Sharks sense electrical signals given off by muscles and hearts of other animals.
-
Lateral Line: A special organ along their body lets sharks feel vibrations and movement in the water.
-
Vision: Many sharks have excellent night vision and can see well in low-light or murky water.
-
Magnetic Sensing: Some sharks may use Earth’s magnetic fields to navigate across oceans.
-
Directional Smell: Sharks use their nostrils independently to locate where smells are coming from.
-
Scent Memory: Sharks can remember and return to feeding areas based on scent trails.
-
360° Awareness: Some species, like hammerheads, have wide-set eyes for nearly panoramic vision.
-
Sensitivity: A shark's senses are so refined, they can detect prey hiding under sand or behind rocks.
Raggie shark research
Shark anatomy facts:
-
Sharks have no bones – their skeletons are made of flexible cartilage.
-
They have multiple rows of teeth that fall out and grow back throughout their lives.
-
Shark skin feels like sandpaper, covered in tiny tooth-like scales called dermal denticles.
-
Sharks have large livers filled with oil to help them float.
-
Their streamlined bodies and strong muscles make them powerful, fast swimmers.
Shark reproduction and birth facts:
-
Sharks reproduce slowly, with some taking over 10 years to reach maturity.
-
Baby sharks are called pups, and they are born fully developed and ready to survive on their own.
-
Sharks give birth in 3 ways: laying eggs (oviparous), live birth with a placenta (viviparous), or live birth without a placenta (ovoviviparous).
-
Some egg-laying sharks produce tough, leathery egg cases called “mermaid’s purses.”
-
In some species, pups may eat their siblings in the womb – a behavior known as intrauterine cannibalism.
Whale shark
Raggie shark research
Shark record holder facts:
-
Whale shark – the largest shark and fish on Earth, growing up to 18 meters, feeding mostly on plankton.
-
Basking shark – the second largest shark, reaching 12 meters and weighing up to 7,000 kg.
-
Greenland shark – the longest-living vertebrate, living over 390 years in icy deep waters.
-
Great hammerhead – the biggest hammerhead species, reaching 6 meters, now critically endangered.
-
Shortfin mako shark – the fastest shark, swimming up to 70 km/h in short bursts.
-
Dwarf Lantern shark – the smallest known shark, only about 20 cm long and glowing in the dark!
-
Megalodon (extinct) – the largest predatory shark in history, with teeth over 18 cm long.
-
Bull shark – the most versatile, able to swim in fresh and salt water, even rivers and lakes.
-
Thresher shark – has the longest tail, used like a whip to stun prey.
-
Blue shark – one of the most widespread shark species, found in nearly all oceans around the world.
Rarest-living shark facts:
-
Goblin shark – A deep-sea “living fossil” with a long, flattened snout and extendable jaws; rarely seen alive.
-
Ganges shark – A critically endangered freshwater shark found only in parts of India, with very few sightings.
-
Pondicherry shark – Thought extinct for decades, this rare shark was rediscovered in 2019 and is still barely documented.
-
Pocket shark – A tiny, glowing deep-sea shark with light-producing glands near its fins; only two specimens have ever been found.
-
Northern river shark – A very rare species found in a few freshwater rivers in northern Australia and Papua New Guinea.
Deepest-living shark facts:
-
Goblin shark – Found as deep as 1,300 meters, known for its creepy extendable jaws and ancient lineage.
-
Frilled shark – A deep-sea predator that looks like a sea serpent, found at depths over 1,500 meters.
-
Greenland shark – Lives in the cold, deep waters of the Arctic, often found between 200–1,200 meters, but can go deeper.
-
Portuguese dogfish – One of the deepest-dwelling sharks, recorded at depths up to 3,700 meters.
-
Cookiecutter shark – Found in deep tropical waters, this small shark makes circular bites and can live down to 3,500 meters.
Behavioral shark facts:
-
Some sharks, like Scalloped hammerheads, form large schools, especially during the day.
-
Sharks can show curiosity and intelligence, often investigating new objects or divers.
-
Great white sharks use a behavior called "spy hopping", lifting their heads above water to look around.
-
Sharks communicate through body language, like arching their backs or lowering fins.
-
Sharks are opportunistic hunters, always looking for easy prey that gives the most energy with the least effort.
Shark migration and travel facts:
-
Some sharks migrate thousands of kilometers each year between feeding and breeding grounds.
-
Whale sharks are known to cross entire oceans following plankton blooms.
-
Tagged Great White sharks have been tracked from California to Hawaii and back.
-
Blue sharks are one of the most widely distributed shark species in the world.
-
Oceanic whitetips often travel alone across vast open waters.
Shark facts vs fiction:
-
Myth: Sharks are man-eating monsters.
Truth: Most sharks are shy and avoid humans – attacks are extremely rare. -
Myth: Sharks attack humans on purpose.
Truth: Most bites are mistakes – sharks often confuse people with prey like seals. -
Myth: All sharks are dangerous.
Truth: Out of 500+ species, only a few pose any threat to humans. -
Myth: Sharks are mindless killers.
Truth: Sharks are intelligent, curious, and use strategy when hunting. -
Myth: Shark attacks are common.
Truth: You’re more likely to be struck by lightning or injured by a toaster than bitten by a shark. -
Myth: Sharks will attack anyone in the water.
Truth: Sharks don’t “patrol” for humans – they’re usually hunting fish or moving through their habitat. -
Myth: If you see a shark, it will attack.
Truth: In most encounters, sharks simply pass by or investigate without aggression. -
Myth: Sharks "infest" the ocean.
Truth: Sharks live in the ocean – it’s their home, not ours to label. -
Myth: Killing sharks makes beaches safer.
Truth: Removing sharks disrupts ecosystems and does not reduce attack risk. -
Myth: All sharks must keep swimming or they die.
Truth: Some sharks can rest on the sea floor and breathe using special muscles.
Sharks and culture facts:
-
In many cultures, sharks are respected as symbols of strength, protection, and wisdom.
-
Ancient Hawaiians viewed sharks as ancestral gods or 'aumakua'.
-
Sharks appear in Aboriginal Australian creation stories and rock art.
-
The modern fear of sharks largely stems from media and movies like Jaws.
-
Shark-based tourism is worth over $300 million USD annually worldwide.
Sharks conservation facts:
-
Nearly one-third of all shark and ray species are now listed as threatened or endangered by the IUCN.
-
Species like the great hammerhead, scalloped hammerhead, oceanic whitetip, basking shark, and whale shark are critically endangered.
-
In the South Pacific, endangered mako and blue sharks face severe threats from bycatch in longline fisheries.
-
Over 100 million sharks are killed every year, mainly for their fins, meat, and bycatch in commercial fishing.
-
Many shark species are slow to reproduce, making it extremely difficult for their populations to recover once depleted.
How you can help sharks:
-
Learn & Share Shark Facts – Help bust myths by spreading real shark knowledge. Share this page and check out our resources page.
-
Book a Shark Guardian Presentation – Invite us to your school, group, or dive center. Shark Guardian Presentation Request Form
-
Join Our Campaigns – Support shark protection laws and petitions worldwide. Shark Guardian shark petitions
-
Buy Shark Guardian Merch – Every purchase funds shark education and outreach. Shark Guardian Online Shop
-
Follow & Share on Social Media – Help raise awareness with a like, share, or post.
-
Join a Shark Expedition – Dive with sharks and support eco-tourism that protects them. Shark Guardian Expeditions.
-
Contribute to Citizen Science – Log your shark sightings to help with research and data collection. Visit Shark Guardian Research
-
Donate – Support ongoing education programs, campaigns, and shark conservation efforts. Donate here
-
Fundraise – Support Shark Guardian while shopping online at for FREE! Visit Shark Guardian Fundraising.
-
Become a Shark Guardian Member – A fun and educational way for to get involved for kids and adults. Shark Guardian Membership