lec 20

• predation/carnivory • grazing/herbivory • parasitism/disease

• Predicts that population of predator and prey will cycle overtime • When theres Many prey in the population, the predator will eat them and the population of prey will increase • Since the predator ate all the prey, the prey population goes down • Since there’s not much food anymore the predator population also goes down • The prey population will go up since the amount of predator decreased

• If predator and prey are coevolving, the prey evolves a kind of defense for the predator and the predator will evolve a counter adaptation • It wont change their net interactions

Prey are under strong selection to make defenses than predators are to make the counter adaptations

Enemy release hypothesis: in their native environment, their population is kept in check by their enemies but in their new environment, they are free to spread without any enemies

• lays their eggs in other birds nests • By doing this, the bird does not have to care for their offspring • Brood parasites birds have evolved similar egg shape, size, and color to not get caught by their host • Parasites have traits that help them escape detection by host