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 message The Nearctic realm is one of the eight biogeographic realms constituting the Earth s land surface The Nearctic realm The 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 ecoregionsvte Sonoran Sinaloan transition subtropical dry forest Mexico Nearctic tropical and subtropical coniferous forests ecoregionsvte Bermuda subtropical conifer forests Bermuda Nearctic temperate broadleaf and mixed forests ecoregionsvte Allegheny Highlands forests United States Appalachian mixed mesophytic forests United States Appalachian Blue Ridge forests United States Central U S hardwood forests United States East Central Texas forests United States Eastern forest boreal transition Canada United States Eastern Great Lakes lowland forests Canada United States Gulf of St Lawrence lowland forests Canada Middle Atlantic coastal forests United States Mississippi lowland forests United States New England Acadian forests Canada United States Northeastern coastal forests United States Ozark Mountain forests United States Sierra Madre Occidental pine oak forests Mexico United States Sierra Madre Oriental pine oak forests Mexico United States Southeastern mixed forests United States Southern Great Lakes forests Canada United States Upper Midwest forest savanna transition United States Western Great Lakes forests Canada United States Willamette Valley forests United States Nearctic temperate coniferous forests Alberta Mountain forests Canada Alberta British Columbia foothills forests Canada Arizona Mountains forests United States Atlantic coastal pine barrens United States Blue Mountains forests United States British Columbia mainland coastal forests Canada United States Cascade Mountains leeward forests Canada United States Central and Southern Cascades forests United States Central British Columbia Mountain forests Canada Central Pacific coastal forests Canada United States Colorado Rockies forests United States Eastern Cascades forests Canada United States Fraser Plateau and Basin complex Canada Florida scrub United States Great Basin montane forests United States Haida Gwaii Canada Klamath Siskiyou forests United States Middle Atlantic coastal forests United States North Central Rockies forests Canada United States Northern California coastal forests United States Northern Pacific coastal forests Canada United States Northern transitional alpine forests Canada Okanagan dry forests Canada United States Piney Woods forests United States Puget lowland forests Canada United States Sierra Juarez and San Pedro Martir pine oak forests Mexico Sierra Nevada forests United States South Central Rockies forests United States Southeastern conifer forests United States Wasatch and Uinta montane forests United States Nearctic boreal forests taiga ecoregionsvte Alaska Peninsula montane taiga United States Central Canadian Shield forests Canada Cook Inlet taiga United States Copper Plateau taiga United States Eastern Canadian forests Canada Eastern Canadian Shield taiga Canada Interior Alaska Yukon lowland taiga Canada United States Mid Continental Canadian forests Canada Midwestern Canadian Shield forests Canada Muskwa Slave Lake forests Canada Newfoundland Highland forests Canada Northern Canadian Shield taiga Canada Northern Cordillera forests Canada Northwest Territories taiga Canada South Avalon Burin oceanic barrens Canada France Saint Pierre and Miquelon Southern Appalachian spruce fir forest United States Southern Hudson Bay taiga Canada Yukon Interior dry forests Canada Nearctic tropical and subtropical grasslands savannas and shrublands ecoregionsvte Western Gulf coastal grasslands Mexico United States Nearctic temperate grasslands savannas and shrublands ecoregionsvte California Central Valley grasslands United States Canadian aspen forests and parklands Canada United States Central and Southern mixed grasslands United States Central forest grasslands transition United States Central tall grasslands United States Columbia Plateau United States Edwards Plateau savanna United States Flint Hills tall grasslands United States Montana valley and foothill grasslands United States Nebraska Sand Hills mixed grasslands United States Northern mixed grasslands Canada United States Northern short grasslands Canada United States Northern tall grasslands Canada United States Palouse grasslands United States Texas blackland prairies United States Western short grasslands United States Nearctic tundra ecoregionsvte Alaska St Elias Range tundra Canada United States Aleutian Islands tundra United States Arctic coastal tundra Canada United States Arctic foothills tundra Canada United States Baffin coastal tundra Canada Beringia lowland tundra United States Beringia upland tundra United States Brooks British Range tundra Canada United States Davis Highlands tundra Canada High Arctic tundra Canada Interior Yukon Alaska alpine tundra Canada United States Kalaallit Nunaat high arctic tundra Greenland Kalaallit Nunaat low arctic tundra Greenland Low Arctic tundra Canada Middle Arctic tundra Canada Ogilvie MacKenzie alpine tundra Canada United States Pacific Coastal Mountain icefields and tundra Canada United States Torngat Mountain tundra Canada Nearctic Mediterranean forests woodlands and scrub ecoregionsvte California coastal sage and chaparral Mexico United States California interior chaparral and woodlands United States California montane chaparral and woodlands United States Nearctic deserts and xeric shrublands ecoregionsvte Baja California desert Mexico Central Mexican matorral Mexico Chihuahuan desert Mexico United States Colorado Plateau shrublands United States Columbia Plateau shrublands Canada United States Great Basin shrub steppe United States Gulf of California xeric scrub Mexico Meseta Central matorral Mexico Mojave Desert United States Snake Columbia shrub steppe United States Sonoran Desert Mexico United States Tamaulipan matorral Mexico Tamaulipan mezquital Mexico United States Wyoming Basin shrub steppe United States Nearctic mangroves ecoregionsvte Northwest 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,
