For years, the megalodon has been imagined as a monstrous version of the great white shark. Depictions in movies and documentaries show a stocky, torpedo-shaped predator, built for speed and power.

Megalodon have always been compared to the modern great white shark. Scientists have found a reason why it shouldn't be.

The ocean’s most formidable cold-hearted killer, the long-extinct giant megalodon shark, may have been warm-blooded – which could have caused its disappearance more than three million years ago.