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
System anatomy models. One of the key features of the system anatomy is its simplicity. That, of course, means that the anatomy cannot replace other models or design tools. It is only another way of describing the design, in SW tools, on paper or in the heads of the system engineers. The system anatomy can be used as a starting point when creating an integration anatomy (aka project anatomy) that has more use as a project management tool. The following example is a simplified example of a system anatomy for an issue management system. "This anatomy is drawn with the most basic