Of course. There was a highly contagious and lethal to humans strain of H5N1, avian influenza. The leaders of the time decided to use another virus to counteract it, which was designed to kill the infected birds. Instead of killing the birds, however, it started to change the size of their brains and body structure with each generation. Now, we're a bit shy of the average size a human is, and so far there are only a few species of birds with enough intelligence to even attend school. They're getting there, though. The quails are a much more recent addition to our society, and doves were the first.