The World Wildlife Fund (WWF) divides the Nearctic into four bioregions, defined as "geographic clusters of ecoregions that may span several habitat types, but have strong biogeographic affinities, particularly at taxonomic levels higher than the species level (genus, family)."
Although North America and South America are presently joined by the Isthmus of Panama, these continents were separated for about 180 million years, and evolved very different plant and animal lineages. When the ancient supercontinent of Pangaea split into two about 180 million years ago, North America remained joined to Eurasia as part of the supercontinent of Laurasia, while South America was part of the supercontinent of Gondwana. North America later split from Eurasia. North America has been joined by land bridges to both Asia and South America since then, which allowed an exchange of plant and animal species between the continents, the Great American Interchange.
A former land bridge across the Bering Strait between Asia and North America allowed many plants and animals to move between these continents, and the Nearctic realm shares many plants and animals with the Palearctic. The two realms are sometimes included in a single Holarctic realm.
Subfamily Tremarctinae (short-faced bears) – including the giant short-faced bear (Arctodus simus). The only surviving member of the group is the spectacled bear (Tremarctos ornatus) of South America.
Flora and fauna endemic to the Nearcticedit
One bird family, the wrentits (Timaliinae), is endemic to the Nearctic region. Two mammal families are endemic to the Nearctic, the pronghorns (Antilocapridae) and the mountain beaver (Aplodontiidae).[2] The Holarctic has four endemic families: divers (Gaviidae), grouse (Tetraoninae), auks (Alcidae), and the waxwings (Bombycillidae). The scarab beetle families Pleocomidae and Diphyllostomatidae (Coleoptera) are also endemic to the Nearctic. The fly species Cynomya cadaverina is also found in high numbers in this area.
Abell, R.A. et al. (2000). Freshwater Ecoregions of North America: A Conservation Assessment Washington, DC: Island Press, Freshwater Ecoregions of North America: A Conservation Assessment.
Flannery, Tim (2001). The Eternal Frontier: an Ecological History of North America and its Peoples. Grove Press, New York.
Ricketts, Taylor H., Eric Dinerstein, David M. Olson, Colby J. Loucks, et al. (1999). Terrestrial Ecoregions of North America: a Conservation Assessment. Island Press, Washington DC., Terrestrial Ecoregions of North America: A Conservation Assessment.
External linksedit
Wikimedia Commons has media related to Nearctic.
Wikivoyage has a travel guide for North American wildlife.
nearctic, realm, thoroughbred, racehorse, nearctic, horse, this, article, includes, list, general, references, lacks, sufficient, corresponding, inline, citations, please, help, improve, this, article, introducing, more, precise, citations, november, 2013, lea. For the thoroughbred racehorse see Nearctic horse This article includes a list of general references but it lacks sufficient corresponding inline citations Please help to improve this article by introducing more precise citations November 2013 Learn how and when to remove this template message The Nearctic realm is one of the eight biogeographic realms constituting the Earth s land surface The Nearctic realmThe Nearctic realm covers most of North America including Greenland Central Florida and the highlands of Mexico The parts of North America that are not in the Nearctic realm include most of coastal Mexico southern Mexico southern Florida coastal central Florida Central America and the Caribbean islands Together with South America these regions are part of the Neotropical realm Contents 1 Major ecological regions 1 1 Canadian Shield 1 2 Eastern North America 1 3 Western North America 1 4 Northern Mexico 2 History 3 Flora and fauna 3 1 Flora and fauna that originated in the Nearctic 3 2 Flora and fauna endemic to the Nearctic 4 Nearctic terrestrial ecoregions 5 See also 6 References 7 External linksMajor ecological regions editThe World Wildlife Fund WWF divides the Nearctic into four bioregions defined as geographic clusters of ecoregions that may span several habitat types but have strong biogeographic affinities particularly at taxonomic levels higher than the species level genus family Canadian Shield edit The Canadian Shield bioregion extends across the northern portion of the continent from the Aleutian Islands to Newfoundland It includes the Nearctic s arctic tundra and boreal forest ecoregions In terms of floristic provinces it is represented by part of the Canadian Province of the Circumboreal Region Eastern North America edit The Eastern North America bioregion includes the temperate broadleaf and mixed forests of the Eastern United States and southeastern Canada the Great Plains temperate grasslands of the central United States and south central Canada the temperate coniferous forests of the southeastern United States including central Florida In terms of floristic provinces it is represented by the North American Atlantic Region and part of the Canadian Province of the Circumboreal Region Western North America edit The Western North America bioregion includes the temperate coniferous forests of the coastal and mountain regions of southern Alaska western Canada and the western United States from the Pacific Coast and Northern California to the Rocky Mountains known as the Cascadian bioregion as well as the cold winter intermountain deserts and xeric shrublands and temperate grasslands and shrublands of the Western United States In terms of floristic provinces it is represented by the Rocky Mountain region Northern Mexico edit The Northern Mexico bioregion includes the mild winter to cold winter deserts and xeric shrublands warm temperate and subtropical pine and pine oak forests and Mediterranean climate ecoregions of the Mexican Plateau Baja California peninsula and the southwestern United States bordered to the south by the Neotropical Trans Mexican Volcanic Belt 1 This region also includes the only subtropical dry broadleaf forest in the Nearctic realm the Sonoran Sinaloan transition subtropical dry forest In terms of floristic provinces it is represented by the Madrean Region History editAlthough North America and South America are presently joined by the Isthmus of Panama these continents were separated for about 180 million years and evolved very different plant and animal lineages When the ancient supercontinent of Pangaea split into two about 180 million years ago North America remained joined to Eurasia as part of the supercontinent of Laurasia while South America was part of the supercontinent of Gondwana North America later split from Eurasia North America has been joined by land bridges to both Asia and South America since then which allowed an exchange of plant and animal species between the continents the Great American Interchange A former land bridge across the Bering Strait between Asia and North America allowed many plants and animals to move between these continents and the Nearctic realm shares many plants and animals with the Palearctic The two realms are sometimes included in a single Holarctic realm Many large animals or megafauna including horses camels tapirs mammoths mastodons ground sloths sabre tooth cats Smilodon short faced bears and the American cheetah became extinct in North America at the end of the Pleistocene epoch ice ages in what is called the Quaternary extinction event Flora and fauna editFlora and fauna that originated in the Nearctic edit Mammals originally unique to the Nearctic include Order Primates the first primate proto primate Purgatorius originated in the Early Paleocene of the Nearctic Family Canidae dogs wolves foxes and coyotes Family Camelidae camels and their South American relatives including the llama Now extinct in the Nearctic Family Equidae horses donkeys and their relatives Now only found in the Nearctic as feral horses Family Tapiridae tapirs now extinct in the Nearctic Family Antilocapridae last survivor of which is the pronghorn Subfamily Tremarctinae short faced bears including the giant short faced bear Arctodus simus The only surviving member of the group is the spectacled bear Tremarctos ornatus of South America Flora and fauna endemic to the Nearctic edit One bird family the wrentits Timaliinae is endemic to the Nearctic region Two mammal families are endemic to the Nearctic the pronghorns Antilocapridae and the mountain beaver Aplodontiidae 2 The Holarctic has four endemic families divers Gaviidae grouse Tetraoninae auks Alcidae and the waxwings Bombycillidae The scarab beetle families Pleocomidae and Diphyllostomatidae Coleoptera are also endemic to the Nearctic The fly species Cynomya cadaverina is also found in high numbers in this area Plant families endemic or nearly endemic to the Nearctic include the Crossosomataceae Simmondsiaceae and Limnanthaceae Nearctic terrestrial ecoregions editNearctic tropical and subtropical dry broadleaf forests ecoregionsvteSonoran Sinaloan transition subtropical dry forest MexicoNearctic tropical and subtropical coniferous forests ecoregionsvteBermuda subtropical conifer forests BermudaNearctic temperate broadleaf and mixed forests ecoregionsvteAllegheny Highlands forests United StatesAppalachian mixed mesophytic forests United StatesAppalachian Blue Ridge forests United StatesCentral U S hardwood forests United StatesEast Central Texas forests United StatesEastern forest boreal transition Canada United StatesEastern Great Lakes lowland forests Canada United StatesGulf of St Lawrence lowland forests CanadaMiddle Atlantic coastal forests United StatesMississippi lowland forests United StatesNew England Acadian forests Canada United StatesNortheastern coastal forests United StatesOzark Mountain forests United StatesSierra Madre Occidental pine oak forests Mexico United StatesSierra Madre Oriental pine oak forests Mexico United StatesSoutheastern mixed forests United StatesSouthern Great Lakes forests Canada United StatesUpper Midwest forest savanna transition United StatesWestern Great Lakes forests Canada United StatesWillamette Valley forests United StatesNearctic temperate coniferous forestsAlberta Mountain forests CanadaAlberta British Columbia foothills forests CanadaArizona Mountains forests United StatesAtlantic coastal pine barrens United StatesBlue Mountains forests United StatesBritish Columbia mainland coastal forests Canada United StatesCascade Mountains leeward forests Canada United StatesCentral and Southern Cascades forests United StatesCentral British Columbia Mountain forests CanadaCentral Pacific coastal forests Canada United StatesColorado Rockies forests United StatesEastern Cascades forests Canada United StatesFraser Plateau and Basin complex CanadaFlorida scrub United StatesGreat Basin montane forests United StatesHaida Gwaii CanadaKlamath Siskiyou forests United StatesMiddle Atlantic coastal forests United StatesNorth Central Rockies forests Canada United StatesNorthern California coastal forests United StatesNorthern Pacific coastal forests Canada United StatesNorthern transitional alpine forests CanadaOkanagan dry forests Canada United StatesPiney Woods forests United StatesPuget lowland forests Canada United StatesSierra Juarez and San Pedro Martir pine oak forests MexicoSierra Nevada forests United StatesSouth Central Rockies forests United StatesSoutheastern conifer forests United StatesWasatch and Uinta montane forests United StatesNearctic boreal forests taiga ecoregionsvteAlaska Peninsula montane taiga United StatesCentral Canadian Shield forests CanadaCook Inlet taiga United StatesCopper Plateau taiga United StatesEastern Canadian forests CanadaEastern Canadian Shield taiga CanadaInterior Alaska Yukon lowland taiga Canada United StatesMid Continental Canadian forests CanadaMidwestern Canadian Shield forests CanadaMuskwa Slave Lake forests CanadaNewfoundland Highland forests CanadaNorthern Canadian Shield taiga CanadaNorthern Cordillera forests CanadaNorthwest Territories taiga CanadaSouth Avalon Burin oceanic barrens Canada France Saint Pierre and Miquelon Southern Appalachian spruce fir forest United StatesSouthern Hudson Bay taiga CanadaYukon Interior dry forests CanadaNearctic tropical and subtropical grasslands savannas and shrublands ecoregionsvteWestern Gulf coastal grasslands Mexico United StatesNearctic temperate grasslands savannas and shrublands ecoregionsvteCalifornia Central Valley grasslands United StatesCanadian aspen forests and parklands Canada United StatesCentral and Southern mixed grasslands United StatesCentral forest grasslands transition United StatesCentral tall grasslands United StatesColumbia Plateau United StatesEdwards Plateau savanna United StatesFlint Hills tall grasslands United StatesMontana valley and foothill grasslands United StatesNebraska Sand Hills mixed grasslands United StatesNorthern mixed grasslands Canada United StatesNorthern short grasslands Canada United StatesNorthern tall grasslands Canada United StatesPalouse grasslands United StatesTexas blackland prairies United StatesWestern short grasslands United StatesNearctic tundra ecoregionsvteAlaska St Elias Range tundra Canada United StatesAleutian Islands tundra United StatesArctic coastal tundra Canada United StatesArctic foothills tundra Canada United StatesBaffin coastal tundra CanadaBeringia lowland tundra United StatesBeringia upland tundra United StatesBrooks British Range tundra Canada United StatesDavis Highlands tundra CanadaHigh Arctic tundra CanadaInterior Yukon Alaska alpine tundra Canada United StatesKalaallit Nunaat high arctic tundra GreenlandKalaallit Nunaat low arctic tundra GreenlandLow Arctic tundra CanadaMiddle Arctic tundra CanadaOgilvie MacKenzie alpine tundra Canada United StatesPacific Coastal Mountain icefields and tundra Canada United StatesTorngat Mountain tundra CanadaNearctic Mediterranean forests woodlands and scrub ecoregionsvteCalifornia coastal sage and chaparral Mexico United StatesCalifornia interior chaparral and woodlands United StatesCalifornia montane chaparral and woodlands United StatesNearctic deserts and xeric shrublands ecoregionsvteBaja California desert MexicoCentral Mexican matorral MexicoChihuahuan desert Mexico United StatesColorado Plateau shrublands United StatesColumbia Plateau shrublands Canada United StatesGreat Basin shrub steppe United StatesGulf of California xeric scrub MexicoMeseta Central matorral MexicoMojave Desert United StatesSnake Columbia shrub steppe United StatesSonoran Desert Mexico United StatesTamaulipan matorral MexicoTamaulipan mezquital Mexico United StatesWyoming Basin shrub steppe United StatesNearctic mangroves ecoregionsvteNorthwest Mexican Coast mangroves MexicoSee also editList of ecoregions in Canada WWF List of ecoregions in Mexico WWF List of ecoregions in the United States WWF References edit Ecoregions 2017 c ecoregions appspot com Retrieved 2023 01 25 Nearctic Mammals 22 July 2021 Abell R A et al 2000 Freshwater Ecoregions of North America A Conservation Assessment Washington DC Island Press Freshwater Ecoregions of North America A Conservation Assessment Flannery Tim 2001 The Eternal Frontier an Ecological History of North America and its Peoples Grove Press New York Ricketts Taylor H Eric Dinerstein David M Olson Colby J Loucks et al 1999 Terrestrial Ecoregions of North America a Conservation Assessment Island Press Washington DC Terrestrial Ecoregions of North America A Conservation Assessment External links edit nbsp Wikimedia Commons has media related to Nearctic nbsp Wikivoyage has a travel guide for North American wildlife Map of the ecozones Nearctica The Natural World of North America Nearctic Region New International Encyclopedia 1905 Retrieved from https en wikipedia org w index php title Nearctic realm amp oldid 1184109928, wikipedia, wiki, book, books, library,
