On land, plants make their own food by photosynthesis and animals live by eating. However, in the microscopic world in the oceans, it is not that simple. Many microscopic so-called plants (phytoplankton) can also eat like animals and many microscopic so-called animals (microzooplankton) can also photosynthesize like plants! More amazingly, some of these microzooplankton eat tiny phytoplankton and continue to live off photosynthesis from those ingested phytoplankton. These organisms acting like both plants and animals
are called mixotrophs because they mix (combine) different ways of getting nutrition. These fascinating creatures are not rare freaks of nature, but are very common. Some mixotrophs are good food for fish, while others make poisons that can get into our seafood and even kill fish. Some are increasing in coastal waters due to pollution. We are learning just how important mixotrophs are to ocean ecosystems.