Predation

In ecology, predation describes a biological interaction where a predator (an organism that is hunting) feeds on its prey, the organism that is attacked.

Evolution of predation
Predation appears to have become a major selection pressure shortly before the Cambrian period—around 550 Ma—as evidenced by the almost simultaneous development of calcification in animals and algae, and predation-avoiding burrowing. However, predators had been grazing on micro-organisms since at least 1000 Ma.