The Komodo dragon is the largest living lizard and a fearsome predator. It’s long been thought that some of its hunting prowess was due to a mouth teeming with bacteria. An attack that didn’t immediately kill the dragon’s victim—often a deer, but sometimes a person—would cause fatal bacterial infections. But a report released May 18th by the Proceedings of the National Academy of Sciences finds a more likely cause of death.

The animal has evolved a “sophisticated combined-arsenal killing apparatus.” First, the animal has razor-sharp serrated teeth—perfect for tearing flesh and causing massive wounds. But, wait, there’s more. When the researchers performed an MRI of a dragon, they found in its jaws what they called the most structurally complex reptile venom gland known. The gland has openings between the lizard’s teeth and releases chemicals that both dilate blood vessels and prevent blood clotting. The inevitable result is massive blood loss. This new information thus helps to clean up the foul-mouthed reputation of the Komodo dragon. But it’s little solace for its unfortunate prey.

—Adam Hinterthuer