A population of songbirds breeds in the summer at location A and winters at location B. If half the population begins staying at location B year-round, which of the following is most likely to happen?
A. a population crash among the songbirds that stay at location B year-round
B. a population bottleneck of both populations of songbirds
C. intraspecies competition events between the two populations of songbirds
D. genetic divergence of the two populations of songbirds
