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8 Algae
A plant at the base of ecosystems and the food chain
Ar bezhin e diazez an ekosistemoù ha chadenn ar magañ
Algae supply half of all the organic matter of plant origin on our planet, and they lie at the base of the food chain in the oceans.
It is phytoplankton — the microscopic form of algae — that feeds the zooplankton, which is then eaten by other marine animals.
Macroalgae provide food for grazing animals such as abalone and winkles, which are eaten in their turn by carnivores and omnivores.
Who eats whom?
A marine food chain follows a precise order. Could you put it back together?
Seaweed → shrimp → abalone → crab → seal.
Every link depends on the one before it: take away the seaweed, and the whole structure collapses.