A glacial relict is a
population
Population typically refers to the number of people in a single area, whether it be a city or town, region, country, continent, or the world. Governments typically quantify the size of the resident population within their jurisdiction using a ...
of a cold-adapted species that has been left behind as the range of the species changed after an
ice age
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gree ...
ended. Glacial relicts are usually found in enclaves "under relatively benign conditions".
Examples:
*The
biogeography
Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, ...
of various aquatic species deemed glacial relicts that are found in
Lake Sommen is likely related to a different geography during the early history of the lake. One theory claims that aquatic species were transferred from the
Baltic Ice Lake
The Baltic Ice Lake is a name given by geologists to a freshwater lake that evolved in the Baltic Sea basin as glaciers retreated from that region at the end of the last ice age. The lake existed between 12,600 and 10,300 years Before Present ...
through a natural
lock system in connection with a temporary advance of the ice-front during the Younger Dryas.
On land, the unusual occurrence of
dwarf birch
''Betula nana'', the dwarf birch, is a species of birch in the family Betulaceae, found mainly in the tundra of the Arctic region.
Description
It is a monoecious, deciduous shrub growing up to high. The bark is non-peeling and shiny red-copper ...
near
Sund is also judged to be a leftover from a cold geological past.
See also
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Biodiversity hotspot
A biodiversity hotspot is a biogeographic region with significant levels of biodiversity that is threatened by human habitation. Norman Myers wrote about the concept in two articles in ''The Environmentalist'' in 1988 and 1990, after which the co ...
*
Last Glacial Maximum refugia
Last Glacial Maximum refugia were places ('' refugia'') in which humans and other species survived during the Last Glacial Period in the Northern Hemisphere, around 25,000 to 20,000 years ago.
Sub-Saharan Africa and Australia were not affected ...
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Nunatak hypothesis In biogeography, particularly phytogeography, the nunatak hypothesis about the origin of a biota in formerly glaciated areas is the idea that some or many species have survived the inhospitable period on icefree land such as nunataks. Its antithes ...
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Rapoport's rule
Rapoport's rule is an ecogeographical rule that states that latitudinal ranges of plants and animals are generally smaller at lower latitudes than at higher latitudes.
Background
Stevens (1989) named the rule after Eduardo H. Rapoport, who had e ...
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Relict (biology)
In biogeography and paleontology, a relict is a population or taxon of organisms that was more widespread or more diverse in the past. A relictual population is a population currently inhabiting a restricted area whose range was far wider during a ...
References
{{Glaciology-stub
Phytogeography
Biogeography
Ice ages
Prehistory of the Arctic
pl:Relikt glacjalny