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28-471: It is notable for its unique flora and fauna and species richness. The region is designated a biodiversity hotspot by Conservation International (CI), and one of the outstanding Global 200 ecoregions by the World Wide Fund for Nature (WWF). As defined by CI, the hotspot lies east and north-east of New Guinea and encompasses some 1,600 islands with a land area of nearly 100,000 km, including

56-545: A continent . This hotspot includes a number of ecoregions that make up the northeastern portion of the Australasian realm . 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

84-492: A measure of geodiversity. Because geodiversity has been shown to be correlated with biodiversity, even as species move in response to climate change, protected areas with high geodiversity may continue to protect biodiversity as niches get filled by the influx of species from neighboring areas. Highly geodiverse protected areas may also allow for the movement of species within the area from one land facet or elevation to another. Conservation scientists, however, emphasize that

112-419: A meteor strike, and global, multiyear effects occur. The sweepstake-winning species happens to already be living in a fortunate site, and their environment is rendered even more advantageous, as opposed to the "losing" species, which immediately fails to reproduce. Ecological understanding and geographic identification of climate refugia that remained significant strongholds for plant and animal survival during

140-571: A once more widespread species. This isolation ( allopatry ) can be due to climatic changes, geography, or human activities such as deforestation and overhunting. 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

168-521: A result of rapid deforestation. Other areas include the Tropical Andes, Philippines, Mesoamerica, and Sundaland, which, under the current levels at which deforestation is occurring, will likely lose most of their plant and vertebrate species. Only a small percentage of the total land area within biodiversity hotspots is now protected. Several international organizations are working to conserve biodiversity hotspots. Most biodiversity exists within

196-553: A species inhabits during the period of a glacial/interglacial cycle that represents the species' maximum contraction in geographical range," and "areas where local populations of a species can persist through periods of unfavorable regional climate." In systematic conservation planning , the term refugium has been used to define areas that could be used in protected area development to protect species from climate change . The term has been used alternatively to refer to areas with stable habitats or stable climates. More specifically,

224-658: A temporary state; however, some refugia may be longstanding, thereby having many endemic species , not found elsewhere, which survive as relict populations. The Indo-Pacific Warm Pool has been proposed to be a longstanding refugium, based on the discovery of the "living fossil" of a marine dinoflagellate called Dapsilidinium pastielsii , currently found in the Indo-Pacific Warm Pool only. For plants, anthropogenic climate change propels scientific interest in identifying refugial species that were isolated into small or disjunct ranges during glacial episodes of

252-950: The Bismarck Archipelago (including the Admiralty Islands ), the Santa Cruz Islands , the Solomon Islands Archipelago (including Bougainville Island ), and the Vanuatu Islands . Politically, the hotspot includes the Islands Region of Papua New Guinea (including Bougainville ) and all of Solomon Islands and Vanuatu . The East Melanesian Islands has many plants and some animals whose ancestors arrived from neighboring New Caledonia and New Guinea , but differ from those islands in that they were never joined to

280-552: 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. Beginning in 2010 the concept of geodiversity (a term used previously in efforts to preserve scientifically important geological features) entered into

308-542: The Last Glacial Maximum ) in sparsely wooded areas and dispersed through areas of high primary productivity while avoiding dense forest cover . Glacial refugia, where human populations found refuge during the last glacial period, may have played a crucial role in shaping the emergence and diversification of the language families that exist in the world today. More recently, refugia has been used to refer to areas that could offer relative climate stability in

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336-722: 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 —or by the extinction of coevolved animal dispersers . The concern is that ongoing warming trends will expose them to extirpation or extinction in the decades ahead. In anthropology , refugia often refers specifically to Last Glacial Maximum refugia , where some ancestral human populations may have been forced back to glacial refugia (similar small isolated pockets on

364-411: The southern hemisphere .) Each site becomes a refugium, one as a "cold-surviving refugium" and the other as a "hot-surviving refugium". Canyons with deep hidden areas (the opposite of hillsides, mountains, mesas, etc. or other exposed areas) lead to these separate types of refugia. A concept not often referenced is that of "sweepstakes colonization": when a dramatic ecological event occurs, for example

392-540: The area may have been a refugium. Moreover, the current distribution of species with narrow ecological requirements tend to be associated with the spatial position of glacial refugia. One can provide a simple explanation of refugia involving core temperatures and exposure to sunlight. In the northern hemisphere , north-facing sites on hills or mountains, and places at higher elevations count as cold sites . The reverse are sun- or heat-exposed, lower-elevation, south-facing sites: hot sites . (The opposite directions apply in

420-432: The biodiversity hotspots approach has resulted in some criticism. Papers such as Kareiva & Marvier (2003) have pointed out that biodiversity hotspots (and many other priority region sets) do not address the concept of cost, and do not consider phylogenetic diversity . Refugium (population biology) In biology, a refugium (plural: refugia ) is a location which supports an isolated or relict population of

448-614: The coast are predicted to experience overall less warming than areas toward the interior of the US State of Washington . 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. The same study found that such effects in the Pacific Northwest would create important refugia for bird species. A review of refugia-focused conservation strategy in

476-424: The concept was revised following thorough analysis by Myers and others into "Hotspots: Earth's Biologically Richest and Most Endangered Terrestrial Ecoregions" and a paper published in the journal Nature , both in 2000. To qualify as a biodiversity hotspot on Myers' 2000 edition of the hotspot map, a region must meet two strict criteria: it must contain at least 1,500 species of vascular plants (more than 0.5% of

504-597: The extremes of past cooling and warming episodes largely pertain to the Quaternary glaciation cycles during the past several million years, especially in the Northern Hemisphere . A number of defining characteristics of past refugia are prevalent, including "an area where distinct genetic lineages have persisted through a series of Tertiary or Quaternary climate fluctuations owing to special, buffering environmental characteristics", "a geographical region that

532-483: The face of modern climate change . As an example of a locale refugia study, Jürgen Haffer first proposed the concept of refugia to explain the biological diversity of bird populations in the Amazonian river basin . Haffer suggested that climatic change in the late Pleistocene led to reduced reservoirs of habitable forests in which populations become allopatric. Over time, that led to speciation : populations of

560-659: The face of the continental ice sheets ) during the last glacial period . 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 . Archaeological and genetic data suggest that the source populations of Paleolithic humans survived the glacial maxima (including

588-660: The infertile ground has previously dissuaded human populations. The conservation of OCBILs within biodiversity hotspots has started to garner attention because current theories believe these sites provide not only high levels of biodiversity, but they have relatively stable lineages and the potential for high levels of speciation in the future. Because these sites are relatively stable, they can be classified as refugia . North and Central America The Caribbean South America Europe Africa Central Asia South Asia Southeast Asia and Asia-Pacific East Asia West Asia The high profile of

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616-409: The late 1990s and early 2000s. The most recent efforts have used the idea of land facets (also referred to as geophysical settings , enduring features , or geophysical stages ), which are unique combinations of topographical features (such as slope steepness, slope direction, and elevation ) and soil composition, to quantify physical features. The density of these facets, in turn, is used as

644-659: 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. While the language to describe this mode of conservation planning hadn't fully developed until recently, the use of geophysical diversity in conservation planning goes back at least as far as the work by Hunter and others in 1988, and Richard Cowling and his colleagues in South Africa also used "spatial features" as surrogates for ecological processes in establishing conservation areas in

672-425: The planet's surface. Ten hotspots were originally identified by Myer; the current 36 used to cover more than 15.7% of all the land but have lost around 85% of their area. This loss of habitat is why approximately 60% of the world's terrestrial life lives on only 2.4% of the land surface area. Caribbean Islands like Haiti and Jamaica are facing serious pressures on the populations of endemic plants and vertebrates as

700-643: The same species that found themselves in different refugia evolved differently, creating parapatric sister-species . As the Pleistocene ended, the arid conditions gave way to the present humid rainforest environment, reconnecting the refugia. 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 . Theoretically, current biogeographical patterns can be used to infer past refugia: if several unrelated species follow concurrent range patterns,

728-495: The term in situ refugium is used to refer to areas that will allow species that exist in an area to remain there even as conditions change, whereas ex situ refugium refers to an area into which species distributions can move to in response to climate change. Sites that offer in situ refugia are also called resilient sites in which species will continue to have what they need to survive even as climate changes. One study found with downscaled climate models that areas near

756-449: The tropics; likewise, most hotspots are tropical. Of the 36 biodiversity hotspots, 15 are classified as old, climatically-buffered, infertile landscapes (OCBILs). These areas have been historically isolated from interactions with other climate zones, but recent human interaction and encroachment have put these historically safe hotspots at risk. OCBILs have mainly been threatened by the relocation of indigenous groups and military actions, as

784-491: The world's total) as endemics , and it has to have lost at least 70% of its primary vegetation. Globally, 36 zones qualify under this definition. These sites support nearly 60% of the world's plant, bird, mammal, reptile, and amphibian species , with a high share of those species as endemics. Some of these hotspots support up to 15,000 endemic plant species, and some have lost up to 95% of their natural habitat. Biodiversity hotspots host their diverse ecosystems on just 2.4% of

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