For decades, the accepted scientific view has been that the single-celled microscopic plankton can be divided broadly into two types. Food producing “phytoplankton” (also known as microalgae) act rather like tiny marine plants. Animal-like single-celled plankton “protozooplankton”, on the other hand, eat the phytoplankton, and are in turn eaten by bigger organisms going up the food chain all the way to fish and whales. This division of these microscopic plankton is thus akin to the plant-animal split in terrestrial food webs. However, we now know that this division is wrong. It transpires that many of the “plant-like phytoplankton”, and half the “animal-like protozooplankton” are mixoplankton!