Glacier mice are colonies of
mosses
Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta ('' sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and ho ...
found on some
glaciers
A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...
and adjacent ecosystems. They are composed of multiple species of moss
and can also host other species, such as
nematode worms,
springtails
Springtails (class Collembola) form the largest of the three lineages of modern Hexapoda, hexapods that are no longer considered insects. Although the three lineages are sometimes grouped together in a class called Entognatha because they have in ...
, and
water bears. Although what preconditions are necessary for glacier mice to form has yet to be determined, they have been observed in Alaska, Chile, Greenland, Iceland, Svalbard, Uganda and Venezuela, as well as several
Subantarctic islands
The sub-Antarctic zone is a physiographic region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region inc ...
. In at least some cases, glacier mice apparently reproduce
asexually due to the effect of the harsh glacier environment on traditional moss reproduction strategies.
Glacier mice are notable for their movement across the ice, which appears to be non-random, taking the form of herd-like behavior. This movement is as yet unexplained,
and does not appear to be solely the product of wind or the direction of a slope. On average, they move about per day.
The use of
accelerometers
An accelerometer is a device that measures the proper acceleration of an object. Proper acceleration is the acceleration (the rate of change of velocity) of the object relative to an observer who is in free fall (that is, relative to an inertia ...
has demonstrated that glacier mice do in fact rotate and roll, rather than simply sliding across the ice, over time exposing all of their surfaces.
Measurements of glacier mice show that they retain heat and moisture, creating a suitable ecosystem for microorganisms that otherwise could not live on a glacier. Glacier mice are believed to persist for six years or longer.
Glacier mice were first described in 1950 by Icelandic meteorologist
Jón Eyþórsson
Jón Pétur Eyþórsson (27 January 1895 – 6 March 1968) was an Icelandic meteorologist. He is known for his work measuring glaciers and tracking the relationship between glacial movement and weather patterns. Jón also coined the term " gla ...
, who referred to them as , which is
Icelandic for "glacier mice."
References
External links
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* The Natural History Museum, London: {{YouTube, nQMpkgsWdYg, The secret world of glacier mice
Glaciers
Mosses