A population of birds is blown by a storm to an island off the mainland.
The island has very few trees, and the bird population on the island
develops new nesting behaviors. Mainland birds nest in trees, island birds
nest on the ground. After a long period of time, the island birds are
reunited with the mainland birds, it is observed that the two populations
can no longer interbreed. This is an example of: *
Behavioral isolation
Geographical isolation
Nonrandom mating
All of these