Sometimes, very different organisms get together and form a successful consortium. Lichens, for instance are a symbiotic consortium between and algae and a fungus. In the plankton we have similar relationships. For instance, a ciliate and an alga, once in a while stop being grazer and prey and work together for a better success. This is the case of the ciliate Eutintinnus sp. and the diatom Chaetoceros (usually Chaetoceros tetrastichon or C. dadayi). The ciliate gets protected by the long spines of the Chaetoceros and this, at its turn, gets to travel for free. It is very rare to find both species alone.
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Plankton Ocean 