The taxonomy of birds has always had a few puzzle areas in it, but now, thanks to genetic sequencing, birds now have been classified accurately. www.nflnr.com/photo/content/detay/Birds%20family%20tree.jpg http://www.nflnr.com/science-27/what-happened-to-birds-teeth-recent-genetic-study-solves-150-year-old-mystery-1067.html