Predatory red animals use their color to attract curious unsuspecting prey. Regarding the smaller animals, their color serves as a form of aposematic coloration, warning predictors of imminent toxicity.
Their red color warns predators that they are foul to eat. If that doesn’t deter predators, they can play dead and secret a foul-smelling alkaloid from their limbs. They are dependent on aphids for food and help control the aphid population.
This fish inhabits the deepest and lowest parts of the ocean, where their laterally compressed body and red colors help them blend in with the coral reefs. Cardinal scorpion fish are highly poisonous.
These organisms can reproduce sexually by releasing sperm and egg into the ocean, fertilizing them. Or by asexual reproduction, where a limb is broken off and regenerated into a separate individual.