What Is a Megalodon Shark?

Megalodon, which likely grew to lengths of upwards of 50 feet, is regarded as one of the largest vertebrate predators ever to live. Its wide-ranging distribution in ancient oceans likely had a profound impact on the composition of marine ecosystems. The precise reason for megalodon's extinction is unknown, though it was likely a combination of cool oceans, a decline in food supply and increased competition from other large animals, primarily carnivorous whales.