Explain how a change in the environment could cause a population crash

Rutherford's experiment indicated that matter was not as uniform as it appears what part of his experimental results implied this idea

Monkeys and bats have similar bone structure in their forelimbs. however, monkeys have longer forelimbs to use for climbing and swinging in trees. bats have shorter forelimbs to use for flight. which term best describes how monkey and bat forelimbs are related to each other? a. homologous b. embryonic c. analogous d. vestigial

Is this a single replacement reaction or there is no