Phasianinae

The Phasianinae (Horsfield, 1821) are a subfamily under the family Phasianidae of the order Galliformes. This subfamily notably includes the true pheasants, tragopans, tetraonids, Coturnicini, Pavonini, amongst other members.^[1]

Although this placement was once considered monophyletic and separate from the partridges, francolins and Old World quail (now-defunct Perdicinae) until the early 1990s,^[1][2] molecular phylogenies have shown that this subfamily is paraphyletic. For instance, certain genera like Lophophorus and Meleagris, as well as members of the genus Perdix, are cladistically more closely related to grouse and true pheasants, whereas other genera like Tetraogallus, Coturnix, and members in the genus Alectoris, share a much closer kinship to peafowl and junglefowl.^[3][4] There are two clades in this subfamily: the erectile clade and the non-erectile clade, referring to erectile tissue in the bare, non-feathered parts of the face. Both clades are believed to have diverged during the early Oligocene, about 30 million years ago.^[5]

The Phasianinae are characterized by strong sexual dimorphism, with males being highly ornate not limited to distinct coloration and patterning, as well as adornments such as combs, wattles, air sacs, tufts, crests, and long modified uppertail coverts (trains) and rectrices. Males are typically larger and heavier than females. Males play little to no part in rearing their offspring except a few species like the willow ptarmigan.^[6]

Their diet generally consists of seeds, grains, greens, and some invertebrates, with several being seasonally-specialized herbivores like grouse.^[7]