Refugium (population biology)

Present examples of refugial animal species are the mountain gorilla, isolated to specific mountains in central Africa, and the Australian sea lion, isolated to specific breeding beaches along the south-west coast of Australia, due to humans taking so many of their number as game.

This resulting isolation, in many cases, can be seen as only a temporary state; however, some refugia may be longstanding, thereby having many endemic species, not found elsewhere, which survive as relict populations.

[1] For plants, anthropogenic climate change propels scientific interest in identifying refugial species that were isolated into small or disjunct ranges during glacial episodes of the Pleistocene, yet whose ability to expand their ranges during the warmth of interglacial periods (such as the Holocene) was apparently limited or precluded by topographic, streamflow, or habitat barriers[2][3][4]—or by the extinction of coevolved animal dispersers.

Going from west to east, suggested examples include the Franco-Cantabrian region (in northern Iberia), the Italian and Balkan peninsulas, the Ukrainian LGM refuge, and the Bering Land Bridge.

Haffer suggested that climatic change in the late Pleistocene led to reduced reservoirs of habitable forests in which populations become allopatric.

Scholars have since expanded the idea of this mode of speciation and used it to explain population patterns in other areas of the world, such as Africa, Eurasia, and North America.

[17] Other research has found that old-growth forests are particularly insulated from climatic changes due to evaporative cooling effects from evapotranspiration and their ability to retain moisture.

A review of refugia-focused conservation strategy in the Klamath-Siskiyou Ecoregion found that, in addition to old-growth forest, the northern aspects of hillslopes and deep gorges would provide relatively cool areas for wildlife and seeps or bogs surrounded by mature and old-growth forests would continue to supply moisture even as water availability decreases.

[19] Beginning in 2010 the concept of geodiversity (a term used previously in efforts to preserve scientifically important geological features) entered into the literature of conservation biologists as a potential way to identify climate change refugia and as a surrogate (in other words, a proxy used when planning for protected areas) for biodiversity.