C.S. Holling defined three functional responses of this phenomenon in a paper analysing its effect on the European sawfly. The tendency for models of this phenomenon to destabilise in response to an increase in resource availability is called the paradox of enrichment. Selfish-herd theory, the confusion effect and the dilution effect are hypotheses based on this activity which try to explain why organisms benefit from living in (*) groups. This activity can cause periodic population fluctuations, which are often compared to the stable limit cycles in the Lotka-Volterra model (-5[1])of this activity. (10[1]-5[1])Organisms may use Müllerian mimicry, Batesian mimicry or crypsis to defend themselves against this activity. (10[1])For 10 points, name this activity, in which organisms catch, kill and eat other (10[1])organisms, known as prey. ■END■