Dear Student,
Prey and predators have a interspecific interaction, where prey is an animal which is being hunted for food and predator is an animal which hunts prey for food.
Predator have a control over sudden increase or decrease in prey population.
Along with this predator maintains diversity in prey population.
Two or more species in prey population tends towards co-existence so that they can protect themselves from predator attack.
This mechanism of co-existence reduces competition among prey population.
And more than one or two species are co-existing together in a population means eventually biodiversity is increased.
Thus predator has dual role- reducing competition and maintaining diversity in prey population.
Regards.