Question

Which is most likely to happen to a population that becomes anatomically isolated from the rest of its species?
The entire species will become extinct.
The population will become a separate species over time.
The population will breed with a different species nearby.
The entire species will continue to have viable offspring together.

Answer 1

The population will become a separate species over time.

Reason: Anatomical (geographic) isolation prevents gene flow, so separated populations accumulate different mutations, natural selection and genetic drift act independently, and reproductive isolation can evolve — leading to speciation.