Like the largest fish today, the whale sharks and basking sharks, "Leedsichthys problematicus" derived its nutrition as a suspension feeder, using an array of specialised gill rakers lining its gill basket to extract zooplankton, small animals, from the water passing through its mouth and across its gills. It is less clear whether also phytoplankton, algae, were part of the diet. "Leedsichthys" could have been a ram feeder, making the water pass through its gills by swimming, but could also have actively pumped the water through the gill basket. In 2010, Liston suggested that fossilised furrows discovered in ancient sea floors in Switzerland and attributed to the activity of plesiosaurs, had in fact been made by "Leedsichthys" spouting water through its mouth to disturb and eat the benthos, the animals dwelling in the sea floor mud.