Sharks are one of the most iconic animals on Earth. But what about those species that aren’t known for being ferocious predators? There are some truly bizarre shark species that live in incredible environments, eat strange food, and even look like they belong in another world. Here are seven types of sharks you might not know existed.
1. Sandbar Shark
The sandbar shark is actually a relative of rays, such as stingrays, and skates, according to the American Museum of Natural History. They spend much of their lives buried in the sand, camouflaged by their brownish coloration. And while they don’t typically hunt down prey, they can use their long snouts to pick up fish and crustaceans from the ocean floor.
2. Pygmy Seahorse
These tiny creatures are found off the coast of Australia and New Zealand, where they live in shallow waters near coral reefs. Scientists believe they swim around using echolocation, emitting high-pitched sounds that bounce off objects nearby. This allows them to navigate without relying on sight.
3. Humphead Wrasse
Humphead wrasses are native to tropical oceans, including the Indian Ocean, the Pacific Ocean, and the Atlantic Ocean. These fish are often seen swimming alone, though sometimes they travel in groups. Their unusual name comes from the humpbacked appearance of their heads. The fish has also been known to climb onto land to escape danger.
4. Giant Isopod
Giant isopods are related to shrimp, lobsters, and crabs, which means they have ten legs, two antennae, and one big clawed foot. That single claw contains between 50 and 100 individual joints. They’re basically an alien life form that lived inside the ocean until 15 years ago. In 2002, scientists discovered giant isopods living in methane gas bubbles located under the seafloor.
5. Sea Dragon
Also known as elasmobranchs or chimaeras, sea dragons are a group of marine reptiles that includes sharks, skates, and rays. They are believed to be the first vertebrates to make it to the water, possibly as early as 500 million years ago. Some species have become extinct, but others survive today. The sea dragon pictured here doesn’t have any natural predators, so it will probably end up on your plate if you happen to catch it.
6. Ghost Shark
Ghost sharks are a group of sharks that includes dogs, cats, and alligators, as well as other mysterious creatures. They live in warm, deep coastal waters around the world, and are more commonly spotted at night than during the day. Although ghost sharks are good swimmers, they rarely leave the safety of deeper waters.
7. Flying Fish
Flying fish are dolphins that can lift themselves out of the water, propel themselves through the air with electric pulses, and then dive back into the depths of the ocean. Species abound throughout the world, but many are threatened due to overfishing.
Lemon sharks: Fishy friends
The researchers used underwater cameras to track the animals’ movements over several days. They found that the sharks spent most of their time hanging around other sharks they already knew.
When they did venture off on their own, they swam close to each other, even though there wasn’t much else around.
Whale sharks: Gentle giants
The giant fish known as whale sharks are gentle giants. They rarely attack humans, even though some people think they do. They generally ignore divers unless they bump into one accidentally. And they’re usually pretty curious about what you’re doing underwater.
But don’t worry: These whales are mostly slurping up little shrimp like plankton about the size of a few grains of sand, according to National Geographic Explorer-in-Residence Dr. Robert Hueter. “They filter it through their gills,” he explains. “And they swallow it whole.”
Hueter points out that the biggest threats to whale sharks are boats and nets used by commercial fishermen. He adds that they’re often caught unintentionally while trying to eat jellyfish.
Chain catsharks: Green glowers
The world’s largest predatory shark, the great white, is known for its viciousness toward humans. But one species of shark takes a different approach to hunting prey. Scientists recently discovered that some sharks have a secret weapon: glowing skin.
These sharks live in the deepest parts of the oceans, where sunlight barely penetrates. So how do they see in the dark? By reflecting light off their bodies. And because the color of the reflected light depends on whether the shark is male or female, scientists believe the sharks use this feature to communicate with each other.
Scientists know about this phenomenon thanks to a unique experiment conducted in 2008. At night, researchers lowered cameras into the waters near South Africa to watch what happened down there. They found that the sharks had a distinct pattern of glowing spots on their backs. This pattern changed depending on the sex of the animal, suggesting that the sharks could use the glowing marks to identify each other.
Researchers later confirmed this theory through genetic analysis. In 2016, they collected samples of DNA from seven different populations of great whites, including four populations that live close together. When they ran the DNA through a computer program designed to analyze the data, they saw that the animals from the same population shared the same glowing spot patterns.
But why did the sharks develop this trait? Researchers don’t know. One possibility is that the sharks developed this behavior millions of years ago, long before humans came along to hunt them. Another possibility is that the sharks evolved this behavior to avoid predators.
Either way, the discovery of this behavior suggests that we might discover even stranger behaviors among sharks in the future.
Great white sharks: Picky eaters
Sharks are one of nature’s most fearsome creatures. They’re known to attack humans, and some species even kill entire schools of fish to feed themselves. So what do we know about these apex predators? Well, aside from the fact that they’ve been around since the age of dinosaurs, there isn’t much else. Great white sharks are among the largest predatory fishes in the world, reaching lengths of over 20 feet and weighing up to 2,000 pounds. They live in warm oceans around the globe, including Australia, South Africa, Japan, Indonesia, and the United States. Though they don’t hunt very often, they prefer to feast on large marine mammals such as whales, seals, and sea turtles. When they do go hunting, however, they’ll take down prey much larger than themselves. A shark’s mouth contains rows of sharp, pointed teeth, each of which is capable of tearing into flesh. These teeth are arranged in three rows along the upper jaw, and each tooth in the middle row is longer than those above and below. This allows the shark to tear apart the meat of its meals without having to move its head too far forward. Some scientists theorize that the arrangement of the teeth also helps the shark detect the vibrations made by prey swimming nearby.
The great white shark has an average lifespan of 30-40 years, but it can grow to be older than 100. The oldest recorded great white was caught in 1938 off the coast of New Zealand. It measured more than 16 feet long and weighed nearly 1,500 pounds.
Bonnethead sharks: Salad snackers
Scientists say it might be a case of mistaken identity. Bonnethead sharks are known to gobble up everything from fish to sea turtles. But scientists think some of those sharks could be getting confused about what they’re actually eating. They’ve found evidence that bonnetheads are leafy-green snacking machines. And unlike most other sharks, which are primarily carnivorous and don’t eat plants like seaweed, bonnetheads have developed a unique digestive tract that allows them to absorb nutrients from green leaves.
Spinner sharks: Airborne acrobats
Most sharks are bottom dwellers, swimming slowly along the ocean floor hunting for food. Spinner sharks, however, are different. They’re air-born gliders.
The sharks glide beneath a school of fish, looking for easy pickings among the group. Once spotted, the shark bursts out of the water and lunges forward, snatching up a fish.
But wait—there’s more. The shark isn’t finished there. It needs to make sure it gets what it came for. So it keeps circling around the school, waiting for another chance to strike.
This aerial maneuver, known as “spinning,” helps the shark catch its next meal.
FUN FACTS ABOUT SHARKS
Sharks are fish related to rays and skates. They spend most of their lives near the bottom of the ocean where they eat small animals like crabs and shrimp. A few sharks live above water, including great whites, hammerheads, and tiger sharks. Great white sharks can grow up to 18 feet long and weigh over 3,500 pounds. Hammerhead sharks are smaller, growing up to 12 feet long and weighing around 2,200 pounds. Tiger sharks can reach up to 15 feet long and weigh up to 4,000 pounds.
• There are about 5,700 species of sharks.
• Sharks have existed since prehistoric times. Scientists believe sharks evolved from ancient lobe-finned fishes.
• In the United States, there are seven kinds of sharks that swim in our waters: sandbar sharks, blacktip reef sharks, nurse sharks, lemon sharks, bull sharks, tiger sharks, and gray reef sharks.
• The average person spends five minutes looking at a shark.
• The world’s largest living shark is the whale shark, which grows to be 40 feet long.
• Shark attacks happen mostly in warm seas and tropical areas. Most shark bites occur during dusk and dawn hours when people are swimming in shallow water.
• Sharks use their teeth to tear flesh and break bones. Their jaws contain hundreds of tiny, razor-sharp teeth.
• Sharks’ eyesight is poor because light reflects back into their eyes. Instead of having one big eye on top of their head, sharks have three rows of small eyes.
• Sharks have no eyelids or eyebrows.
• Sharks do not sweat. Sweat glands help keep sharks cool by evaporating moisture from their bodies.
• Sharks cannot taste with their mouths; instead, they smell with their noses.
• Sharks have two hearts. One heart pumps blood through the body while the second pumps oxygenated blood to the gills.
• Sharks breathe through gill slits located behind their heads. When a shark breathes, water moves in and out of these slits.
• Sharks have scales made of keratin, the same material as human fingernails. These scales protect sharks from injury and help them move smoothly through the water.
• Sharks have been known to attack humans, but this happens very rarely. Only six fatal shark attacks have occurred in U.S. waters since 1900.