Calcariidae

Members of Calcariidae range in mass from around (the chestnut-collared longspur) to around (McKay's bunting). Species have brown, grey, and white plumage, with dark brown or black irises. The legs of the snow bunting and McKay's bunting are dark gray or black, while legs of other species in the family range from dull pink to brown. == Taxonomy ==

The birds in Calcariidae were formerly assigned to the family Emberizidae (typically known as buntings in the Old World and sparrows in the New World). They proposed to place them in the tribe Calcariini, Timing with the cytochrome b DNA suggests that the Calcariidae diverged from a common ancestor around 4.2–6.2 million years ago, around the beginning of the Pliocene, possibly soon after spread of grasslands in North America as the climate in the late Miocene became drier and cooler. The Lapland longspur likely diverged from an ornatus/pictus ancestor near the beginning of the Pliocene (4.4–6.2 million years ago) and the snow and McKay's buntings diverged within the last 100,000–125,000 years. Though they differ in appearance, Smith's and the collared longspurs likely only diverged around 1.5–2 million years ago, around the start of the Pleistocene. However, a 2007 study by Maley and Winker found substantial differences in the juvenile plumage between the two groups, supporting a species-level division. Other members of Calcariidae known to hybridize with each other are the thick-billed longspur and the chestnut-collared longspur. ==Distribution and habitat==

in Alaska. This species breeds mainly in the Arctic tundra and winters in northern temperate areas. The range of the family is extensive. Of the six species within the family, the snow bunting and Lapland longspur are found both in both North America and Eurasia; the other four species are found only in North America. Additionally, the snow bunting has been recorded as a vagrant to Algeria and Morocco in North Africa, the Balkans, Greece and Turkey, and Malta. The Lapland longspur's range is similar to that of the snow bunting, breeding in northern Canada, Scandinavia, and Siberia, and coastal Alaska and Greenland and wintering in the northern United States and Canada, and in a band between approximately 45° and 55° latitude across Russia, Kazakhstan, China, and Mongolia to the Sea of Japan. Smith's longspur breeds in Alaska and northern Canada, and winters in the central southern United States. The chestnut-collared longspur's breeding range consists solely of prairie regions in the northern Great Plains and southern Canadian Prairies, while its winter range extends from the southern United States to central Mexico. Members of Calcariidae generally inhabit open areas, including prairies, plains, shores, farmland, and beaches. Parts of the snow bunting's range include mountainous areas. ==Behavior==

The diet of species in this family consists of insects, seeds, and grasses. Species are diurnal, and forage by walking and picking up food from the ground. ==References==