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
Scientific socialism Scientific socialism Scientific socialism is a term coined in 1840 by Pierre-Joseph Proudhon in his "What is Property?" to mean a society ruled by a scientific government, i.e. one whose sovereignity rests upon reason, rather than sheer will: Thus, in a given society, the authority of man over man is inversely proportional to the stage of intellectual development which that society has reached; and the probable duration of that authority can be calculated from the more or less general desire for a true government, — that is, for a scientific government. And just as the right of force and the