All sharks are carnivores. From the sunny surface waters to the darkest depths, every selachian species lives by feeding on other animals. Of course, the great whites, tigers, and the ones that get lots of basic cable screen time – the macropredators – are the most famous, but the largest sharks of all feed on some of the smallest organisms in the ocean. These sharks are planktivores, and paleontologists have rediscovered two ancient sharks that pioneered a diet based on the very very tiny.

The Cretaceous sharks took a circuitous course to discovery. Back in 2007, Kenshu Shimada – a professor at DePaul University and research associate at Kansas’ Sternberg Museum of Natural History – described the plankton-feeding, megamouth shark Megachasma