Jellyfish don’t look all that appetizing. They’re also armed to the bell with some of the deadliest chemical weapons on Earth. They don’t even make for a very hearty meal. So it seems unlikely that small, feathery penguins would willingly seek this potentially dangerous prey.

Yet that’s the conclusion of a new paper published this month in Frontiers in Ecology and the Environment. “It is hard to believe that penguins, which are endothermic animals and thus need fair amounts of energy from their food to keep their bodies warm, could find any benefit in eating relatively energy-poor prey like jellyfish, especially in freezing Antarctic waters,” says Jean-Baptiste Thiebot, a postdoctoral fellow with Japan’s National Institute of Polar Research and