Keel (bird anatomy) keel; and ratites (from "ratis", "raft" — referring to the flatness of the sternum), having a subtle keel structure or lacking one entirely. However, this classification has fallen into disuse as evolutionary studies have shown that many flightless birds have evolved from flighted birds. The current definition of Carinatae now includes all extant birds. Keel (bird anatomy) A keel or carina (plural carinae) in bird anatomy is an extension of the sternum (breastbone) which runs axially along the midline of the sternum and extends outward, perpendicular to the plane of the ribs. The keel provides an anchor to which a
Grey's Anatomy least fascinating to watch. To write it off is to unnecessarily narrow the definition of what good TV can be, to limit what the medium is capable of. TV is at its best when it emotionally connects, and even when it seems to be otherwise merrily hurtling off a cliff, Grey's Anatomy is nothing but emotional connection, which is more than other, more consistently better shows can say." The series placed at No. 66 on "Entertainment Weekly" "New TV Classics" list, and was declared the third highest rated show for the first ten years of the Internet Movie Database (2002–2012).