Phasianidae

The Phasianidae  is a family of birds which consists of the pheasants and partridges, including the junglefowl (including chicken), Old World Quail, francolins, monals and peafowl. The family is a large one, and is occasionally broken up into two subfamilies, the Phasianinae, and the Perdicinae. Sometimes additional families and birds are treated as being in this family as well; the American Ornithologists' Union includes Tetraonidae (the grouse), Numididae (guineafowls), and Meleagrididae (turkeys) in Phasianidae as subfamilies.

The earliest fossil records of phasianids date to the late Oligocene epoch, about 30 million years ago.

Distribution
The pheasants and their allies are an Old World family, with a distribution that includes most of Europe and Asia (except the far north), all of Africa except the driest deserts and down into much of eastern Australia and (formerly) New Zealand. The greatest diversity of species is in Southeast Asia and Africa. Amongst the pheasants, with the exception of the Congo Peafowl, the distribution is entirely restricted to Asia; the Perdicinae have a much more widespread distribution. Within their range they occupy almost every available habitat except for boreal forest and tundra.

The family is generally sedentary and resident, although some quails undertake long migrations. Several species in the family have been widely introduced around the world, particularly pheasants which have been introduced to Europe, Australia and the Americas. Captive populations of peacocks and chickens have also escaped and become feral.

Description
Phasianids are terrestrial, ground living species. They are variable in size and ranging from 43 g, in the case of the King Quail, to 6 kg in the case of the Indian Peafowl. There is generally sexual dimorphism in size, with males tending to be larger than females. They are generally plump, with broad relatively short wings and strong legs. Many have a spur on their legs, a feature shared with guineafowl and turkeys but no other galliform birds. The bill is short and generally strong, particularly in species that dig in order to obtain food. Males of the larger species often have brightly coloured plumage as well as facial ornamentations such as wattles or crests.

Behaviour
The pheasants and partridges have a varied diet, with foods taken ranging from purely vegetarian diets of seeds, leaves, fruits, tubers and roots, to small animals including insects, insect grubs and even small reptiles. Most species either specialise in feeding on plant matter or are predatory, although the chicks of most species are insectivorous.

In addition to the variation in diet there is a considerable amount of variation in breeding strategies amongst the Phasianidae. Compared to birds in general there is a large number of species that do not engage in monogamy (the typical breeding system of most birds). The francolins of Africa and some partridges are reportedly monogamous, but polygamy has been reported in the pheasants and junglefowl, some quail, and the breeding displays of peacocks have been compared to those of a lek. Nesting usually occurs on the ground; only the tragopans nest higher up in stumps of bushes. Nests can vary from monds of vegetation to slight scrapes in the ground. As many as 18 eggs can be laid in the nest, although 7-12 is the more usual number, with smaller numbers in tropical species. Incubation is almost always performed by the female only, and last from 14–30 days depending on the species.

Relationship with humans
Several species of pheasant and partridge are extremely important to humans. The Red Junglefowl of Southeast Asia is the wild ancestor of the domesticated chicken, the most important bird in agriculture. Ring-necked Pheasants, several partridge and quail species and some francolins have been widely introduced and managed as game birds for hunting. Several species are threatened by human activities.