Most mammals, including humans, have a constantly dwindling supply of eggs, becoming less fertile with age. But naked mole rats can reproduce for their entire lives—and researchers may have uncovered the fascinating reason how.

Along with having an exceptionally large reserve of healthy egg cells in their ovaries, naked mole rats create new eggs after being born, according to a new study published in the journal Nature Communications. Humans, on the other hand, are likely born with all the eggs we will ever have.

Native to East Africa, naked mole rats have baffled scientists for decades. These wrinkly, communal-living rodents can live up to 37 years, handle extremely low-oxygen conditions, and do not get cancer,