Elephants ought to get a lot of cancer. They’re huge animals, weighing as much as eight tons. It takes a lot of cells to make up that much elephant.

All of those cells arose from a single fertilized egg, and each time a cell divides, there’s a chance that it will gain a mutation — one that may lead to cancer.

Strangely, however, elephants aren’t more prone to cancer than smaller animals. Some research even suggests they get less cancer than humans do.

On Tuesday, a team of researchers reported what may be a partial solution to that mystery: Elephants protect themselves with a unique gene that aggressively kills off cells whose DNA has been damaged.