Arctic-alpine
Encyclopedia
An arctic-alpine taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...

 is one whose natural distribution
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...

 includes the Arctic
Arctic
The Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost...

 and more southerly mountain ranges, particularly the Alps
Alps
The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....

. The presence of identical or similar taxa in both the tundra
Tundra
In physical geography, tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands," "treeless mountain tract." There are three types of tundra: Arctic tundra, alpine...

 of the far north, and high mountain range
Mountain range
A mountain range is a single, large mass consisting of a succession of mountains or narrowly spaced mountain ridges, with or without peaks, closely related in position, direction, formation, and age; a component part of a mountain system or of a mountain chain...

s much further south is testament to the similar environmental conditions found in the two locations.

It is often assumed that an organism which currently has an arctic-alpine distribution was, during colder periods of the Earth's history
History of Earth
The history of the Earth describes the most important events and fundamental stages in the development of the planet Earth from its formation 4.578 billion years ago to the present day. Nearly all branches of natural science have contributed to the understanding of the main events of the Earth's...

 (such as during the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

 glaciations), widespread across the area between the arctic and the Alps. This is known from pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...

 records to be true for Dryas octopetala
Dryas octopetala
Dryas octopetala is an arctic-alpine flowering plant in the family Rosaceae. It is a small prostrate evergreen subshrub forming large colonies, and is a popular flower in rock gardens...

, for instance. In other cases, the disjunct distribution may be the result of long-distance dispersal.

Examples

Examples of arctic-alpine plants include:
  • Dryas octopetala
    Dryas octopetala
    Dryas octopetala is an arctic-alpine flowering plant in the family Rosaceae. It is a small prostrate evergreen subshrub forming large colonies, and is a popular flower in rock gardens...

  • Linnaea borealis
    Twinflower
    Linnaea is a plant genus in the family Caprifoliaceae . The genus includes a single, generally boreal to subarctic woodland subshrub species, Linnaea borealis, commonly known as Twinflower .This plant was a favorite of Carl Linnaeus, founder of the modern system of biological nomenclature, for...

  • Lloydia serotina
    Lloydia serotina
    Lloydia serotina is an arctic-alpine flowering plant of the lily family. It is the only member of the genus Lloydia to live outside central and eastern Asia, and is widespread across western North America, from Alaska to New Mexico, and in Europe is found in the Alps and Carpathians, as well as in...

  • Loiseleuria procumbens
    Loiseleuria procumbens
    The Loiseleuria procumbens, alpine azalea, are dwarf shrubs of high mountain regions of Northern hemisphere that usually grow no more than 10cm. It shares the history of a family Kalmiopsis leachiana...

  • Saxifraga oppositifolia
    Purple Saxifrage
    Saxifraga oppositifolia, the purple saxifrage or purple mountain saxifrage, is a species of edible plant that is very common all over the high Arctic and also some high mountainous areas further south, including northern Britain, the Alps and the Rocky Mountains...

  • Saxifraga stellaris
    Saxifraga stellaris
    Saxifraga stellaris, the starry saxifrage or hairy kidney-wort, is an Arctic-alpine species of saxifrage. It produces panicles of 5–10 white flowers on a stem up to tall, rising from a basal leaf rosette...

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