Despite the time frame involved, it still wont be enough time for creative pressures to select the right mutations.
There are no right or wrong mutations, just beneficial and deleterious. And what was once beneficial may become deleterious, and vice versa. You almost seem to be describing a Lamarkian evolution. Evolution is backward looking, it cannot see what the next step is 'supposed' to be if an end result is 'supposed' to a bird. It is only based on passing along genetically what has let a current generation be successful, as screened out by natural selection.
I mean, this is America. Everybody loves seeing lesbians go at it, as long as they are both hot and not in a monogamous, legally sanctioned relationship.