Scientists have discovered a new species of worm they say has three different sexes – among other unusual traits.

Called ‘Nematodes’, the worms live in California’s Mono Lake, a body of water that contains so much salt and arsenic that almost nothing lives there. In fact, researchers say the worms can survive a dose of arsenic 500 times greater than it would take to kill a human.

If that wasn’t odd enough, Nematodes also carry their young in a pouch, like a kangaroo.

Scientists say nematodes could represent an important breakthrough in understanding how toxins affect human beings.