Symbiosis in plankton

These protists belong to both the vegetal and animal kingdoms. They live in symbiosis with micro-algae.

In this episode

  • DinoflagellatePyrocystis elegans
  • Centric diatom
  • AcantharianLithoptera mulleri
  • RadiolarianAulacantha scolymantha
  • RadiolarianCollozum inerme


Unlike their land relatives, many marine organisms do not belong to either the plant or animal kingdom. They’re both at the same time! These hybrid cells are the result of symbiosis between algae and animals both being single-celled protists. Like all plants, algae produce organic matter using sunlight.

Through photosynthesis, they supply food for their animal host. The host, in turn, nurses its algae by providing optimal conditions: nutrients, exposure to sunlight as well as protection from predators.

Symbiosis is widespread among unicellular organisms, but is important for multi-cellular creatures too: Certain jellyfish or velellas form alliances with algae. Harmonious cooperation helps them survive in the plankton jungle!

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Original Idea
Christian Sardet

Noé Sardet

Scientific consultant
Johan Decelle, Colomban de Vargas

Christian Sardet

Christian Sardet, Sharif Mirshak, Noé Sardet

Noé Sardet

Bernard Dubreuil

Sound Engineer
Noé Sardet

Bernard Dubreuil (chants de gorge)

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