There is no need for any species to go extinct for evolutionary pressures to select for adaptations that allow for predation on other species. The population o

There is no need for any species to go extinct for evolutionary pressures to select for adaptations that allow for predation on other species. The population of a predator reaching the carrying capacity of the existing prey base is enough to make it evolutionarily advantageous to develop means of adding new species to the prey base, ceteris paribus.