These birds vary in size from small to large, but they are typically stoutly built and have short thick bills primarily adapted for seed-eating or the consumption of other plant material such as heather shoots. The young birds will also take insects.
- Family: Megapodidae, mound-builders
- Family: Cracidae, chachalacas, guans and curassows
- Family: Tetraonidae, grouse
- Family: Phasianidae, partridges, pheasants, quail, and allies.
- Family: Odontophoridae, New World quail
- Family: Numididae, guineafowl
- Family: Meleagrididae, turkeys
- Family: Mesitornithidae, mesites