The birds might populate from island A to island B because their may be less competition there with other birds, I’m not definite on this answer but I hope it helps
The answer is ‘behavioral isolation’. It is a form of
sympatric speciation - which occurs even when
species live in the same habitat. In this case,
the individuals in the population are isolated by differences in mating and probably different mating rituals.
The change in the environment affected how the organism would evolve to be so that it could survive. the term for that is survival of the fittest, and only the fittest would be able to survive the conditions of its surrounding environment. hope this answered your question. :)
