The sternum or breastbone, in vertebrate anatomy, is a flat bone. In amphibians and reptiles it is normally shaped like a shield, often made of cartilage. It is absent in both turtles and snakes. In birds it more large, and has flight muscles attached to it. Only in mammals does the sternum take on the longer form seen in humans.
References[change | change source]
- Romer, Alfred Sherwood; Parsons, Thomas S. (1977). The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. p. 188. .