Pigeons and doves belong to order Columbiformes and family Columbidae. Within family Columbidae, there are five subfamilies consisting of 42 genera and 308 species. Pigeons and doves are found on every continent except Antarctica, and they live in virtually all types of terrestrial habitats. Columbids tend to be stocky birds with relatively small heads, short beaks, as well as a fleshy cere and a bare ring of skin around the eyes. Columbiforms also tend to have short, squat legs and long keels.