Predator–prey reversal is a biological interaction where an organism that is typically prey in the predation interaction instead acts as the predator. A variety of interactions are considered a role reversal.One type is where the prey confronts its predator and the interaction ends with no feeding. Two competing predators may interact and the larger predator will prey on the smaller. Smaller organisms may prey on larger organisms. Changing population densities may trigger a role reversal. In addition, adult prey may attack juvenile predators.