Rangifer granti is a representative of the Barren Ground group of Caribou, which includes R. arcticus of the Arctic Coast and R. granlandicus of Greenland. It is not closely related to R. stonei of the Kenai Peninsula, from which it differs not only in its very much smaller size, but in important cranial characters and in coloration. ...The external and cranial differences between R. granti and the various forms of the Woodland Caribou are so great in almost every respect that no detailed comparison is necessary. ...According to Mr. Stone, Rangifer granti inhabits the " barren land of Alaska Peninsula, ranging well up into the mountains in summer, but descending to the lower levels in winter, generally feeding on the low flat lands near the coast and in the foothills...As regards cranial characters no comparison is necessary with R. montanus or with any of the woodland forms." Life in the tundra is hard, but reindeer have it easy-ish thanks to their amazing evolutionary enhancements. Their noses are specially adapted to warm the air they breathe before it enters their lungs and to condense water in the air, which keeps their mucous membranes moist. Their fur traps air, which not only helps provide them with excellent insulation, but also keeps them buoyant in water, which is important for traveling across massive rivers and lakes during migration.

sex: How to enhance sex, stamina, and libido Best food for sex: How to enhance sex, stamina, and libido

Historically, the Eurasian reindeer and American caribou were considered to be different species, but they are actually one and the same: Rangifer tarandus. There are two major groups of reindeer, the tundra and the woodland, which are divided according to the type of habitat the animal lives in, not their global location. The animals are further divided into nine to 13 subspecies, depending on who is doing the classification. One subspecies, the Arctic reindeer of eastern Greenland, is extinct. 2. Reindeer have several names. However, since 1991, many genetic studies have revealed deep divergence between modern tundra reindeer and woodland caribou. [74] [5] [75] [76] [11] Geist (2007) and others continued arguing that the woodland caribou was incorrectly classified, noting that "true woodland caribou, the uniformly dark, small-maned type with the frontally emphasized, flat-beamed antlers", is "scattered thinly along the southern rim of North American caribou distribution". He affirms that the "true woodland caribou is very rare, in very great difficulties and requires the most urgent of attention." [77] The reindeer is the only successfully semi-domesticated deer on a large scale in the world. Reindeer in northern Fennoscandia (northern Norway, Sweden and Finland) as well in the Kola Peninsula and Yakutia in Russia, are mostly semi-domesticated reindeer, ear-marked by their owners. Some reindeer in the area are truly domesticated, mostly used as draught animals (nowadays commonly for tourist entertainment and races, traditionally important for the nomadic Sámi). Domestic reindeer have also been used for milk, e.g., in Norway. While overall widespread and numerous, some reindeer species and subspecies are rare and three subspecies have already become extinct. [28] [29] As of 2015, the IUCN has classified the reindeer as Vulnerable due to an observed population decline of 40% over the last +25 years. [2] According to IUCN, Rangifer tarandus as a species is not endangered because of its overall large population and its widespread range. [2] a b c d e f g h i j k l m Grubb, P. (2005). Wilson, D. E.; Reeder, D. M. (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rded.). Baltimore, MD: Johns Hopkins University Press. ISBN 0-8018-8221-4. OCLC 62265494.The reindeer or caribou [a] ( Rangifer tarandus) [5] is a species of deer with circumpolar distribution, native to Arctic, subarctic, tundra, boreal, and mountainous regions of Northern Europe, Siberia, and North America. [2] This includes both sedentary and migratory populations. It is the only representative of the genus Rangifer. Herd size varies greatly in different geographic regions. More recent studies suggest the splitting of reindeer and caribou into six distinct species over their range. A 2022 study of ancient environmental DNA from the Early Pleistocene (2 million years ago) Kap Kobenhavn Formation of northern Greenland identified preserved DNA fragments of Rangifer, identified as basal but potentially ancestral to modern reindeer. This suggests that reindeer have inhabited Greenland since at least the Early Pleistocene. Around this time, northern Greenland was 11–19 °C warmer than the Holocene, with a boreal forest hosting a species assemblage with no modern analogue. These are among the oldest DNA fragments ever sequenced. [65] [66] Taxonomy [ edit ] In traditional United States Christmas legend, Santa Claus's reindeer pull a sleigh through the night sky to help Santa Claus deliver gifts to good children on Christmas Eve. Also, researchers found that people who ate avocados had a reduced risk of metabolic syndrome, which is a risk factor for ED.

Reindeer - Wikipedia Reindeer - Wikipedia

A R. t. pearyi-sized caribou occupied Greenland before and after the LGM and persisted in a relict enclave in northeastern Greenland until it went extinct about 1900 (see discussion of R. t. eogroenlandicus below). Archaeological excavations showed that larger barren-ground-sized caribou appeared in western Greenland about 4,000 years ago. [59]

In most cervid species, only males grow antlers; the reindeer is the only cervid species in which females also grow them normally. [114] Androgens play an essential role in the antler formation of cervids. The antlerogenic genes in reindeer have more sensitivity to androgens in comparison with other cervids. [115] [116] Cassidy, A., Franz, M., & Rimm, E. B. (2016, February 1). Dietary flavonoid intake and incidence of erectile dysfunction. The American Journal of Clinical Nutrition, 103(2), 534–541 Although most taxonomic authorities over the years recognized "Greenland Caribou" as a distinct subspecies, several gave the name as a subspecies of Cervus [Rangifer] tarandus for North American barren-ground caribou, groenlandicus having priority over other names. The name dates from George Edwards (1743), [91] who claimed to have seen a male specimen (“head of perfect horns...”) from Greenland and said that a Captain Craycott had brought a live pair from Greenland to England in 1738.