Keel (bird anatomy) 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 bird's wing muscles attach, thereby providing adequate leverage for flight. Keels do not exist on all birds; in particular, some flightless birds lack a keel structure. Historically, the presence or absence of a pronounced keel structure was used as a broad classification of birds into two orders: Carinatae (from "carina", "keel"), having a pronounced
The Anatomy of Revolution personal habits come to naught. The revolutions' "results look rather petty as measured by the brotherhood of man and the achievement of justice on this earth. The blood of the martyrs seems hardly necessary to establish decimal coinage" (p. 259). Brinton concludes that despite their ambitions, the political revolutions he studied brought much less lasting social changes than the disruptions and changes of "what is loosely called the Industrial Revolution", and the top-down reforms of Mustapha Kemal's reforms in Turkey, and the Meiji Restoration or post-World War II MacArthur era in Japan (p. 246). The Anatomy of Revolution The Anatomy