Some 30 trillion cells make you, you. Along with your many microbes, this cellular orchestra keeps your body humming along—your heart hammering, your guts gurgling, and your muscles firing. As you grow older, your cells divide so new ones can replace the old. But with this turnover of cells, genetic errors are almost inevitable. And these mishaps often translate to cancer.

Statistically speaking then, bigger animals, which have more cells, should have greater occurrences of cancer. By that reasoning, elephants, with hundreds of times more cells than smaller mammals, should suffer from the disease at much higher rates. But that isn’t the case.

Now, a study in the journal Cell Reports offers new clues as to why—and the key