Sharks
There are over 400 species of shark in the oceans today. Historically, there were many more: sharks first evolved 400 million years ago. Since the days of the megalodon, a vast array of species have evolved, from the hammerhead to the speedy mako and the famous great white. At an average of 10 metres long, the whale shark is the largest species of fish in the world. Sharks' skeletons are made of cartilage instead of bone, like their cousins, the rays.
Megalodons were warm-blooded, and it may have led to their demise
The amount of energy the giant sharks needed to maintain their body temperature in cold waters may have led to their extinction.
Megalodons may have been driven to extinction by hungry great whites scoffing all their food
Analysis of fossil teeth suggests ancient great whites outcompeted their outsized cousins.
The Suicide Squad | King Shark would be 'screwed' in real-life, explains marine biologist
Scientist Dr Lauren Smith explains why Sylvester Stallone's dunderheaded supervillain would struggle with shrivelling eyes in the real world – and would have no desire to munch on humans.
Young great white sharks use ‘training grounds’ to learn to hunt
Researchers say their work could help prevent the species from becoming extinct.
Megalodon: Amazing facts about the extinct apex shark
You'll be on first-name terms with the Meg after reading this.
Megalodon sharks ate their siblings in the womb, new study suggests
And you thought your family had issues.
Megalodon shark was an absolute unit, scientists confirm
The predator was unusually big for its time.
The world’s biggest fish are female
Female whale sharks rule the oceans, reaching average lengths of 14 metres.
Sharks may have evolved bones and lost them again
A 410-million-year-old fossil may force a rethink of how sharks evolved.
Prehistoric megalodon was a mega-shark that had 'fins as large as an entire adult human'
A 16-metre megalodon was thought to have had a head 4.65 metres long, a dorsal fin approximately 1.62 metres tall and a tail around 3.85 metres high.
Great white shark stomach study shows surprising supper source
A fin above water probably doesn't mean a shark is on the hunt.
Cold War radiation helps scientists to calculate whale sharks' ages
Researchers measured carbon-14 levels in the growth rings of two long-dead whale sharks.
Light shed on secrets of glow-in-the-dark sharks
While we know how corals and jellyfish can fluoresce, researchers haven’t figured out exactly how sharks can do it – until now.
Killer whales' taste for shark liver sends great whites fleeing in terror
Who's afraid of the big bad orca?
First ever omnivorous sharks identified
Bonnethead sharks get the nutrition they require through a diet of vegetation and meat.
Beautiful winners from the Underwater Photographer of the Year 2018 competition
The winning photos from UPY2018 have been announced, with stunning images from around the world of the waters below.
Cannibal animals: 10 gruesome examples of animals eating each other
The animal kingdom is a dangerous place, but it’s not always the obvious predators you should watch out for - sometimes you have to look over your shoulder at your own species.
28 myths of modern life exposed
Do mice really love cheese? Does sugar make kids hyperactive? Do you actually need your five-a-day? We put common beliefs under the microscope to sort the fact from the fantasy
Beautiful images from the Underwater Photographer of the Year 2016 contest
The winners of the UPY2016 contest have been announced featuring a breath-taking array of underwater photos – see the winners and a few more of our favourites.
Are these animals cute or ugly? We just can't decide!
Sometimes there's not much between being a cute animal or a hideous beast, so we found five that tread, fly, swim and hop the fine line between the two. Help us decide whether they're cute as a kitten or winners at the ugly bug ball.
How powerful is a great white shark's jaw?
Though the great white shark can really get its teeth stuck in, it's nowhere near the most forceful bite in the animal kingdom, and it doesn't need to be.
Why have hammerhead sharks evolved their distinctive heads?
We're still some way off from hitting the nail on the head when it comes to these unusually-shaped sharks.