OCEAN

From sunlit reefs to crushing trenches, the ocean is Earth's biggest and least-explored neighborhood.

50 facts

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The frilled shark looks like a living prehistoric snake.

The frilled shark looks like a living prehistoric snake.

This deep-sea shark has 300 needle teeth and a body design unchanged for 80 million years.

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MORE OCEAN FACTS

49 facts

Giant isopods are deep-sea cousins of pill bugs - and can live 5 years without food.

DID YOU KNOW? Giant isopods are deep-sea cousins of pill bugs - and can live 5 years without food. They look like dinner-plate-sized rolypolys, drifting on the cold deep seafloor. 2 min read

The ocean is salty because rivers keep washing salt into it.

DID YOU KNOW? The ocean is salty because rivers keep washing salt into it. For billions of years, water has run off the land carrying minerals - and salt has nowhere to go. 2 min read

A tsunami can cross the entire Pacific in less than a day.

DID YOU KNOW? A tsunami can cross the entire Pacific in less than a day. In deep water it travels 500 mph - as fast as a jet plane. 2 min read

The Moon pulls the ocean toward it - which is what causes tides.

DID YOU KNOW? The Moon pulls the ocean toward it - which is what causes tides. Twice a day the sea rises and falls because Moon gravity is tugging on the water. 2 min read

Half the oxygen you breathe comes from the ocean.

DID YOU KNOW? Half the oxygen you breathe comes from the ocean. Tiny floating plants called phytoplankton produce it - more than all the world's forests combined. 2 min read

Most of Earth's volcanoes are hidden under the ocean.

DID YOU KNOW? Most of Earth's volcanoes are hidden under the ocean. For every volcano on land, there are thousands more we never see. 2 min read

The longest mountain range on Earth is underwater.

DID YOU KNOW? The longest mountain range on Earth is underwater. The Mid-Atlantic Ridge runs 65,000 km - and almost nobody has seen it. 2 min read

The Mariana Trench is deeper than Mount Everest is tall.

DID YOU KNOW? The Mariana Trench is deeper than Mount Everest is tall. Drop Everest in. You'd still need to swim a mile down to touch it. 2 min read

We've explored less than 5% of the world's oceans.

DID YOU KNOW? We've explored less than 5% of the world's oceans. Whole mountain ranges, undiscovered species and lost wrecks are still hidden down there. 2 min read

The ocean covers 71% of Earth's surface.

DID YOU KNOW? The ocean covers 71% of Earth's surface. Looking down from space, our planet is more "Ocean" than "Earth." 2 min read

Tiger sharks have eaten license plates, tires, and a chicken coop.

DID YOU KNOW? Tiger sharks have eaten license plates, tires, and a chicken coop. They're nicknamed the "garbage cans of the sea" because they swallow basically anything. 2 min read

Some sharks have to keep swimming - or they can't breathe.

DID YOU KNOW? Some sharks have to keep swimming - or they can't breathe. Their gills only work when water flows through them. 2 min read

Sharks see electricity through pores on their faces.

DID YOU KNOW? Sharks see electricity through pores on their faces. Tiny gel-filled holes pick up the electric heartbeat of every living thing nearby. 2 min read

Shark skin is made of millions of tiny teeth.

DID YOU KNOW? Shark skin is made of millions of tiny teeth. That's why it feels like sandpaper - and why sharks swim so silently. 2 min read

Bull sharks can swim hundreds of miles up rivers.

DID YOU KNOW? Bull sharks can swim hundreds of miles up rivers. They've been found in the Mississippi, the Amazon, and even Lake Nicaragua. 2 min read

There's a small shark that bites round chunks out of whales.

DID YOU KNOW? There's a small shark that bites round chunks out of whales. The cookiecutter shark takes perfect cookie-shaped scoops - and swims off. 2 min read

Megalodon had teeth the size of dinner plates.

DID YOU KNOW? Megalodon had teeth the size of dinner plates. It was the biggest shark that ever lived - and its bite could crush a small whale. 2 min read

A hammerhead shark sees in nearly 360 degrees.

DID YOU KNOW? A hammerhead shark sees in nearly 360 degrees. The wide flat head puts its eyes far apart - giving it almost a full panoramic view. 2 min read

The whale shark is the biggest fish in the ocean - and it only eats plankton.

DID YOU KNOW? The whale shark is the biggest fish in the ocean - and it only eats plankton. It grows to 40 feet but its throat is no wider than a baseball. 2 min read

Whales sleep with half their brain awake at a time.

DID YOU KNOW? Whales sleep with half their brain awake at a time. One half rests while the other keeps swimming, breathing, and watching. 2 min read

Killer whales are the biggest members of the dolphin family.

DID YOU KNOW? Killer whales are the biggest members of the dolphin family. They hunt in family groups, teach their kids, and each pod has its own dialect. 2 min read

A dead whale on the seafloor feeds a whole ecosystem for decades.

DID YOU KNOW? A dead whale on the seafloor feeds a whole ecosystem for decades. It's called a "whale fall" - and life crowds around it for 50+ years. 2 min read

A narwhal's "horn" is actually a giant tooth - with 10 million nerve endings.

DID YOU KNOW? A narwhal's "horn" is actually a giant tooth - with 10 million nerve endings. It can sense water temperature, pressure, and saltiness. 2 min read

Beluga whales can mimic human speech.

DID YOU KNOW? Beluga whales can mimic human speech. One captive beluga learned to "say" words clearly enough that humans understood. 2 min read

Whales evolved from four-legged mammals that walked on land.

DID YOU KNOW? Whales evolved from four-legged mammals that walked on land. Their closest living cousin is the hippo - and they have leg bones inside their bodies to prove it. 2 min read

The sperm whale has the biggest brain of any animal that ever lived.

DID YOU KNOW? The sperm whale has the biggest brain of any animal that ever lived. It weighs 18 pounds - six times bigger than a human brain. 2 min read

Some deep-sea water is 400°C - without boiling.

DID YOU KNOW? Some deep-sea water is 400°C - without boiling. The pressure is so crushing that the water can't even become steam. 2 min read

3 in 4 deep-sea animals make their own light.

DID YOU KNOW? 3 in 4 deep-sea animals make their own light. In the dark deep ocean, glowing is the default - not the exception. 2 min read

The goblin shark's jaws shoot out of its head when it eats.

DID YOU KNOW? The goblin shark's jaws shoot out of its head when it eats. They look like a horror movie prop - and they really work. 2 min read

The deepest known fish lives 8 kilometers down.

DID YOU KNOW? The deepest known fish lives 8 kilometers down. The Mariana snailfish swims under crushing pressure - and looks like a translucent jelly. 2 min read

There's an octopus that "flies" through deep water with ear-like flaps.

DID YOU KNOW? There's an octopus that "flies" through deep water with ear-like flaps. The dumbo octopus has two big ear-shaped fins it uses like wings. 2 min read

Yeti crabs farm bacteria on their own fuzzy arms.

DID YOU KNOW? Yeti crabs farm bacteria on their own fuzzy arms. They wave their hairy claws over deep-sea vents to grow food in their fur. 2 min read

The vampire squid turns itself inside out to scare off predators.

DID YOU KNOW? The vampire squid turns itself inside out to scare off predators. It pulls its arms up over its head like a spiky umbrella full of teeth. 2 min read

Giant tube worms live without a mouth, gut, or stomach.

DID YOU KNOW? Giant tube worms live without a mouth, gut, or stomach. They grow 6 feet tall and farm bacteria inside their bodies for food. 2 min read

Deep-sea vents host whole ecosystems with no sunlight.

DID YOU KNOW? Deep-sea vents host whole ecosystems with no sunlight. At "black smokers," life thrives on chemicals instead of sun - even in 400°C water. 2 min read

A mantis shrimp's eyes have 12 colour receptors.

DID YOU KNOW? A mantis shrimp's eyes have 12 colour receptors - but see colour worse than us. Humans see with 3 receptors. Mantis shrimp use 12. Surprisingly, scientists found they tell colours apart less precisely than we do. 2 min read

A starfish with 21 arms can destroy entire reefs.

DID YOU KNOW? A starfish with 21 arms can destroy entire reefs. Crown-of-thorns starfish eat coral - and when they swarm, the reef goes white. 2 min read

Sea turtles return to the exact beach they hatched on - using Earth's magnetic field.

DID YOU KNOW? Sea turtles return to the exact beach they hatched on - using Earth's magnetic field. Decades after leaving, a female crosses oceans to lay her own eggs on the same sand. 2 min read

Sea cucumbers throw their own guts at predators.

DID YOU KNOW? Sea cucumbers throw their own guts at predators. When threatened, they fire their organs out their backsides - and grow new ones. 2 min read

Nudibranchs are tiny rainbow sea slugs that steal weapons from their food.

DID YOU KNOW? Nudibranchs are tiny rainbow sea slugs that steal weapons from their food. They eat stinging jellyfish - and recycle the stingers into their own skin. 2 min read

Moray eels have a second set of jaws - hidden in their throat.

DID YOU KNOW? Moray eels have a second set of jaws - hidden in their throat. They shoot the inner jaws forward like the alien from Alien. 2 min read

The stonefish is the most venomous fish in the world.

DID YOU KNOW? The stonefish is the most venomous fish in the world. It sits camouflaged as a rock - and one step on it can kill an adult. 2 min read

Lionfish look beautiful - and have 18 venomous spines hidden in their feathers.

DID YOU KNOW? Lionfish look beautiful - and have 18 venomous spines hidden in their feathers. They're a peaceful-looking predator that's invaded oceans far from home. 2 min read

Some fish run "cleaning stations" - and even sharks visit politely.

DID YOU KNOW? Some fish run "cleaning stations" - and even sharks visit politely. A cleaner wrasse takes parasites off bigger fish. The bigger fish queue up and wait their turn. 2 min read

That white sand beach? A parrotfish probably pooped it.

DID YOU KNOW? That white sand beach? A parrotfish probably pooped it. Parrotfish bite chunks off coral reefs, grind them up, and poop out fine white sand. 2 min read

Clownfish live inside the stinging arms of anemones - on purpose.

DID YOU KNOW? Clownfish live inside the stinging arms of anemones - on purpose. They're the only fish that can swim through anemone tentacles without getting stung. 2 min read

Clownfish are all born male - and the boss becomes female.

DID YOU KNOW? Clownfish are all born male - and the boss becomes female. When the lead female dies, the dominant male simply switches sex to replace her. 2 min read

A blue whale's heart is the size of a small car.

DID YOU KNOW? A blue whale's heart is the size of a small car. The blue whale's heart is so big a small child could crawl through its arteries. 1 min read

We have better maps of Mars than of our own ocean floor.

DID YOU KNOW? We have better maps of Mars than of our own ocean floor. We have better maps of Mars than of our own ocean floor. 1 min read

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