Ecotype

In evolutionary ecology, an ecotype,[note 1] sometimes called ecospecies, describes a genetically distinct geographic variety, population or race within a species, which is genotypically adapted to specific environmental conditions.

Typically, though ecotypes exhibit phenotypic differences (such as in morphology or physiology) stemming from environmental heterogeneity, they are capable of interbreeding with other geographically adjacent ecotypes without loss of fertility or vigor. [1][2][3][4][5]

Definition

An ecotype is a variant in which the phenotypic differences are too few or too subtle to warrant being classified as a subspecies. These can occur in the same geographic region where distinct habitats such as meadow, forest, swamp, and sand dunes provide ecological niches. Where similar ecological conditions occur in widely separated places it is possible for a similar ecotype to occur. This is different than a subspecies, which may exist across a number of different habitats. In animals, ecotypes can be regarded as micro-subspecies that owe their differing characteristics to the effects of a very local environment.[6] Therefore, ecotypes have no taxonomic rank.

Terminology

Ecotypes are closely related to morphs. In the context of evolutionary biology, genetic polymorphism is the occurrence in the equilibrium of two or more distinctly different phenotypes within a population of a species, in other words, the occurrence of more than one form or morph. The frequency of these discontinuous forms (even that of the rarest) is too high to be explained by mutation. In order to be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (whose all members can potentially interbreed). Polymorphism is actively and steadily maintained in populations of species by natural selection (most famously sexual dimorphism in humans) in contrast to transient polymorphisms where conditions in a habitat change in such a way that a "form" is being replaced completely by another.

In fact, Begon, Townsend, and Harper assert that

There is not always clear distinction between local ecotypes and genetic polymorphisms.

The notions "form" and "ecotype" may appear to correspond to a static phenomenon, however; this is not always the case. Evolution occurs continuously both in time and space, so that two ecotypes or forms may qualify as distinct species in only a few generations. Begon, Townsend, and Harper use an illuminating analogy on this:

… the origin of a species, whether allopatric or sympatric, is a process, not an event. For the formation of a new species, like the boiling of an egg, there is some freedom to argue about when it is completed.

Thus ecotypes and morphs can be thought of as precursory steps of potential speciation.

Range and distribution

Experiments indicate that sometimes ecotypes manifest only when separated by great spatial distances (of the order of 1,000 km). This is due to hybridization whereby different but adjacent varieties of the same species (or generally of the same taxonomic rank) interbreed, thus overcoming local selection. However other studies reveal that the opposite may happen, i.e., ecotypes revealing at very small scales (of the order of 10 m), within populations, and despite hybridization.[1]

In ecotypes, it is common for continuous, gradual geographic variation to impose analogous phenotypic and genetic variation.[1] This situation is called cline. A well-known example of a cline is the skin color gradation in indigenous human populations worldwide, which is related to latitude and amounts of sunlight.[7] But often the distribution of ecotypes is bimodal or multimodal. This means that ecotypes may display two or more distinct and discontinuous phenotypes even within the same population. Such phenomenon may lead to speciation and can occur if conditions in a local environment change dramatically through space or time.[1]

Examples

Caribou
Rangifer tarandus caribou, a member of the woodland ecotype.
  • Tundra reindeer and woodland reindeer are two ecotypes of reindeer. The first migrate (travelling 5,000 km) annually between the two environments in large numbers whereas the other (who are much fewer) remain in the forest for the summer.[8] In North America, the species Rangifer tarandus (locally known as caribou,[9][9][10] was subdivided into five subspecies[note 2] by Banfield in 1961.[11][12] Caribou are classified by ecotype depending on several behavioural factors – predominant habitat use (northern, tundra, mountain, forest, boreal forest, forest-dwelling), spacing (dispersed or aggregated) and migration (sedentary or migratory).[13][14][15] For example, the subspecies Rangifer tarandus caribou is further distinguished by a number of ecotypes, including boreal woodland caribou, mountain woodland caribou and migratory woodland caribou)—the migratory George River Caribou Herd, for example in the Ungava region of Quebec.
  • Arabis fecunda, a herb endemic to some calcareous soils of Montana, United States, can be divided into two ecotypes. The one "low elevation" group lives near the ground in an arid, warm environment and has thus developed a significantly greater tolerance against drought than the "high elevation" group. The two ecotypes are separated by a horizontal distance of about 100 km.[1]
  • It is commonly accepted that the Tucuxi dolphin has two ecotypes – the riverine ecotype found in some South American rivers and the pelagic ecotype found in the South Atlantic Ocean.[16] Similarly, it is accepted that the common bottlenose dolphin has two ecotypes in the western North Atlantic.[17]
  • The warbler finch and the Cocos Island finch are viewed as separate ecotypes.[18]
  • The Scots pine (Pinus sylvestris) has 20 different ecotypes in an area from Scotland to Siberia, all capable of interbreeding.[19]
  • A very subtle case of ecotype is the following: It has been observed that two populations of the same Helix snail species separated by only a few hundred kilometers prefer not to cross-mate, i.e. they reject one another as mates. This event probably occurs during the process of courtship, which may last for hours.

See also

Notes

  1. ^ Greek: οίκος = home and τύπος = type, coined by Göte Turesson in 1922
  2. ^ Banfield, who worked with both the Canadian Wildlife Service and the National Museum of Canada, in his often-cited 1961 classification, identified five subspecies of Rangifer tarandus: 1) the largely migratory barren-ground caribou subspecies Rangifer tarandus groenlandicus, which are found mainly in the Canadian territories of Nunavut and the Northwest Territories, along with western Greenland; 2) the subspecies Rangifer tarandus caribou which is divided into ecotypes: boreal woodland caribou, (also known as forest-dwelling, woodland caribou (boreal), mountain woodland caribou and migratory woodland caribou) —the migratory George River Caribou Herd, for example in the Ungava region of Quebec; 3) Rangifer tarandus pearyi (Peary caribou), the smallest of the species, known as Tuktu in Inuktitut, found in the northern islands of Nunavut and the Northwest Territories; 4) Rangifer tarandus granti subspecies Grant’s caribou, which are mainly migratory and live in Alaska and the northern Yukon and 5) the R. t. dawsoni subspecies; † Queen Charlotte Islands caribou from the Queen Charlotte Islands (extinct since 1910)

References

  1. ^ a b c d e Ecology: From individuals to ecosystems by Begon, Townsend, Harper, Blackwell Publishing 4th ed. (2006), p.5,6,7,8
  2. ^ Turesson, Turesson G. (1922). The genotypical response of the plant species to the habitat. Hereditas 3. pp. 211–350.
  3. ^ Molles, Manuel C., Jr. (2005). Ecology: Concepts and Applications (3rd ed.). New York: The McGraw-Hill Companies, Inc. p. 201. ISBN 978-0-07-243969-4.
  4. ^ Environmental Encyclopedia by Bortman, Brimblecombe, Mary Ann Cunningham, William P. Cunningham, Freedman - 3rd ed., p.435, "Ecotype"
  5. ^ "ecotype - Dictionary of botany". botanydictionary.org.
  6. ^ Ernst Mayr (1999). "VIII-Nongeographic speciation". Systematics and the Origin of Species, from the Viewpoint of a Zoologist. Harvard University Press. pp. 194–195. ISBN 9780674862500.
  7. ^ "Race". (2009). Encyclopædia Britannica. Ultimate Reference Suite. Chicago: Encyclopædia Britannica.
  8. ^ "reindeer (Rangifer tarandus)" Encyclopædia Britannica. Ultimate Reference Suite. Chicago: Encyclopædia Britannica, 2009
  9. ^ a b "Designatable Units for Caribou (Rangifer tarandus) in Canada" (PDF), COSEWIC, Ottawa, Ontario: Committee on the Status of Endangered Wildlife in Canada, p. 88, 2011, archived from the original (PDF) on 3 March 2016, retrieved 18 December 2013
  10. ^ COSEWIC 2011:3.
  11. ^ Banfield, Alexander William Francis (1961), "A Revision of the Reindeer and Caribou, Genus Rangifer", Bulletin, Biological Services, National Museum of Canada, 177 (66)
  12. ^ Reindeer
  13. ^ Bergerud, Arthur T. (1996), "Evolving Perspectives on Caribou Population Dynamics, Have We Got it Right Yet?", Rangifer, Special Issue (9): 59–115
  14. ^ Festa-Bianchet, M.; Ray, J.C.; Boutin, S.; Côté, S.D.; Gunn, A.; et al. (2011), "Conservation of Caribou (Rangifer tarandus) in Canada: An Uncertain Future", Canadian Journal of Zoology, 89 (5): 419–434, doi:10.1139/z11-025
  15. ^ Mager, Karen H. (2012), Population Structure and Hybridization of Alaskan Caribou and Reindeer: Integrating Genetics and Local Knowledge (PDF) (PhD dissertation), Fairbanks, Alaska: e University of Alaska Fairbanks, retrieved 27 December 2013
  16. ^ Cunha, H.A; Da Silva, V.M.F; Lailson-Brito, J; Santos, M.C.O; Flores, P.A.C; Martin, A.R; Azevedo, A.F; Fragoso, A.B.L; Zanelatto, R.C; Solé-Cava, A.M (2005). "Riverine and marine ecotypes of Sotalia dolphins are different species". Marine Biology. 148 (2): 449–457. doi:10.1007/s00227-005-0078-2.
  17. ^ Common bottlenose dolphin
  18. ^ Encyclopedia of life sciences, 2007, John Wiley & Sons, "Darwin's Finches"
  19. ^ Introduction to Ecology (1983), J.C. Emberlin, chapter 8
Anolis oculatus

Anolis oculatus, the Dominican anole or eyed anole, is a species of anole lizard. It is endemic to the Caribbean island of Dominica, where it is found in most environments. It is distributed in four main population groups on the island, which were initially described as subspecies and now are recognized as ecotypes. It has a very diverse morphology between these populations, with a ground color that ranges from pale tan or yellow to deep green or brown. It also has patterned markings that range from light-colored speckling to complex marbled patterns, and some populations also have large black-ringed "eye" spots on their flanks. This diversity is the product of adaptation to different ecological conditions found within Dominica, which has made it the subject of numerous studies.

The Dominican anole spends much of the time in trees but mainly hunts on the ground. Insects make up the bulk of its prey, with soft-bodied invertebrates and small vertebrates hunted less frequently. Long-living and late maturing for anoles, the Dominican anole can usually breed from around two to three months of age. Females lay eggs, and breeding can occur at any time of year. Clutches number one or sometimes two eggs and are laid under rocks or leaves on the ground. Although presently widespread and common on Dominica, it faces competition from the Puerto Rican crested anole, an invasive species which has begun to supplant it in part of its range.

Boreal woodland caribou

The boreal woodland caribou (Rangifer tarandus caribou), also known as woodland caribou, woodland caribou (boreal group) and forest-dwelling caribou, is a North American subspecies of the reindeer (or the caribou in North America) with the vast majority of animals in Canada. Unlike the Porcupine caribou and barren-ground caribou, boreal woodland caribou are primarily, but not always, sedentary.The boreal woodland caribou is the largest of the caribou subspecies and is darker in colour than the barren-ground caribou. Valerius Geist, specialist on large North American mammals, described the "true" woodland caribou as ”the uniformly dark, small-manned type with the frontally emphasized, flat-beamed antlers" which is "scattered thinly along the southern rim of North American caribou distribution.” Geist asserts that ”the true woodland caribou is very rare, in very great difficulties and requires the most urgent of attention”, but suggests that this urgency is compromised by the inclusion of the Newfoundland caribou, the Labrador caribou, and Osborn's caribou in the Rangifer tarandus caribou subspecies. In Geist's opinion, the inclusion of these additional populations obscures the precarious position of the “true” woodland caribou.They prefer lichen-rich mature forests and mainly live in marshes, bogs, lakes and river regions. The historic range of the boreal woodland caribou covered over half of present-day Canada, stretching from Alaska to Newfoundland and Labrador. The national meta-population of this sedentary boreal ecotype spans the boreal forest from the Northwest Territories to Labrador (but not Newfoundland). Their former range stretched south into the United States. There are no longer any boreal woodland caribou in New England, Minnesota, Wisconsin or Michigan and only several dozen in Idaho and Washington.

The boreal woodland caribou was designated as threatened in 2002 by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). Environment Canada reported in 2011 that there were approximately 34,000 boreal caribou in 51 ranges remaining in Canada.(Environment Canada, 2011b). In a joint report by Canadian Parks and Wilderness Society (CPAWS) and the David Suzuki Foundation, on the status of boreal woodland caribou, claim that "the biggest risk to caribou is industrial development, which fragments their habitat and exposes them to greater predation. Scientists consider only 30% (17 of 57) of Canada’s boreal woodland caribou populations to be self-sustaining." "They are extremely sensitive to both natural (such as forest fires) and human disturbance, and to habitat damage and fragmentation brought about by resource exploration, road building, and other human activity. New forest growth following destruction of vegetation provides habitat and food for other ungulates, which in turn attracts more predators, putting pressure on woodland caribou."Compared to barren-ground caribou or Alaskan caribou, boreal woodland caribou do not form large aggregations and are more dispersed particularly at calving time. Their seasonal movements are not as extensive. Mallory and Hillis explained how, "In North America populations of the woodland caribou subspecies typically form small isolated herds in winter but are relatively sedentary and migrate only short distances (50 - 150 km) during the rest of the year."The name caribou was probably derived from the Mi'kmaq word xalibu or qalipu meaning "the one who paws".

According to the then-Canadian Wildlife Service Chief Mammalogist, Frank Banfield, the earliest record of Rangifer tarandus caribou in North America is from a 1.6 million year old tooth found in the Yukon Territory. Other early records of caribou include a "45,500-year-old cranial fragment from the Yukon and a 40,600-year-old antler from Quebec."

The ancestral origins of caribou prior to the last glaciation (Wisconsin), which occurred approximately 80,000 to 10,000 years ago, are not well understood, however, during the last glaciation it is known that caribou were abundant and distributed in non-glaciated refugia both north and south of the Laurentide ice sheet.

Brown trout

The brown trout (Salmo trutta) is a European species of salmonid fish that has been widely introduced into suitable environments globally. It includes both purely freshwater populations, referred to as the riverine ecotype, Salmo trutta morpha fario, and a lacustrine ecotype, S. trutta morpha lacustris, also called the lake trout, as well as anadromous forms known as the sea trout, S. trutta morpha trutta. The latter migrates to the oceans for much of its life and returns to fresh water only to spawn. Sea trout in Ireland and Britain have many regional names: sewin in Wales, finnock in Scotland, peal in the West Country, mort in North West England, and white trout in Ireland.

The lacustrine morph of brown trout is most usually potamodromous, migrating from lakes into rivers or streams to spawn, although evidence indicates stocks spawn on wind-swept shorelines of lakes. S. trutta morpha fario forms stream-resident populations, typically in alpine streams, but sometimes in larger rivers. Anadromous and nonanadromous morphs coexisting in the same river appear genetically identical. What determines whether or not they migrate remains unknown.

Cline (biology)

In biology, a cline (from the Greek “klinein”, meaning “to lean”) is a measurable gradient in a single character (or biological trait) of a species across its geographical range. First coined by Julian Huxley in 1938, the “character” of the cline referred to is usually genetic (e.g allele frequency, blood type), or phenotypic (e.g. body size, skin pigmentation). Clines can show smooth, continuous gradation in a character, or they may show more abrupt changes in the trait from one geographic region to the next.A cline refers to a spatial gradient in a specific, singular trait, rather than a gradient in a population as a whole. A single population can therefore theoretically have as many clines as it has traits. Additionally, Huxley recognised that these multiple independent clines may not act in concordance with each other. For example, it has been observed that in Australia, birds generally become smaller the further towards the north of the country they are found. In contrast, the intensity of their plumage colouration follows a different geographical trajectory, being most vibrant where humidity is highest and becoming less vibrant further into the arid centre of the country.

Because of this, clines were defined by Huxley as being an “auxiliary taxonomic principle”; that is, clinal variation in a species is not awarded taxonomic recognition in the way subspecies or species are.While the terms “ecotype” and “cline” are sometimes used interchangeably, they do in fact differ in that “ecotype” refers to a population which differs from other populations in a number of characters, rather than the single character that varies amongst populations in a cline.

Commensalism

Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit from each other, amensalism, where one is harmed while the other is unaffected, and parasitism, where one benefits while the other is harmed. The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected. The commensal relation is often between a larger host and a smaller commensal; the host organism is unmodified, whereas the commensal species may show great structural adaptation consonant with its habits, as in the remoras that ride attached to sharks and other fishes. Remoras feed on their hosts' fecal matter, while pilot fish feed on the leftovers of their hosts' meals. Numerous birds perch on bodies of large mammal herbivores or feed on the insects turned up by grazing mammals.

Coregonus trybomi

Coregonus trybomi is a freshwater whitefish in the Salmonidae family. It is a spring-spawning type of cisco, which probably has evolved from sympatric vendace (Coregonus albula) independently in a number of Swedish lakes. Only one of those populations survives, and it is therefore considered Critically Endangered by the IUCN Red List. The status of Coregonus trybomi as a distinct species is however questionable. By Swedish authorities it is treated as a morphotype or ecotype, not an independent species. It was listed as "Data Deficient" in 2010 but excluded from the national red list in 2015.

Coregonus widegreni

Coregonus widegreni, also called the Valaam whitefish, is putative species of freshwater whitefish, a part of the common whitefish complex (Coregonus lavaretus sensu lato) from Northern Europe. It is a demersal form of freshwater whitefish that feeds on benthic invertebrates. It spawns in late autumn, and can reach a length of 55 cm maximum. It is characterized by a low gill raker density.In the strict sense the name C. widegreni refers to a population of whitefish that inhabits relatively deep waters (50–150 m) of Lake Ladoga in Northwest Russia. More often the range is thought to comprise coastal areas of the Baltic Sea (except southern section of the Swedish coast) and several larger lakes in Sweden (e.g. Vänern, Vättern) and Northwest Russia (Onega). It is one of several types of whitefish co-distributed in Northern Europe and exhibiting different breeding and feeding habits. In the Northern Baltic, C. [lavaretus] widegreni has referred to bottom-feeding whitefish that spawn in the sea ("lesser sparsely-rakered whitefish", in contrast to migratory anadromous whitefish referred to as C. lavaretus lavaretus.In contemporary Nordic usage, C. widegreni is not recognised as a distinct species, but at most as an ecotype or morphotype of Coregonus lavaretus or of Coregonus maraena.

Dwarf killer whale

The familiar killer whale (Orcinus orca) is a cosmopolitan species, found in all oceans of the world. Despite being the most widespread mammal in the world, only one species is currently recognized. Oceanic Science journals have long hinted at the existence of a complex breed of miniature killer whales since the 1950s. The dwarf killer whale is a type of killer whale found in Antarctic waters believed by some scientists to be a distinct species from the larger killer whales found throughout the world's oceans. Since Soviet researchers proposed new species in the 1980s, the differences in killer whales have been studied more closely in order to gain more credible knowledge on possible subspecies of the killer whale. There are several ecotypes that have been established in regards to the whales physical appearances and body length by Pitman and colleagues. A recent study proposed by Pitman et al. (2007) used aerial photogrammetry to determine the size of numerous Type C killer whales, supporting early Soviet research which suggested that one or possibly two distinct species of killer whale exist in the Southern Ocean. Therefore, scientific evidence is starting to make the connection between ecotype C and the dwarf killer whale.

Eastern wolf

The eastern wolf (Canis lupus lycaon) is a subspecies of gray wolf native to the Great Lakes region and southeastern Canada. The subspecies is the product of ancient genetic admixture between the gray wolf and the coyote, however it is regarded as unique and therefore worthy of conservation. There are two forms, the larger being referred to as the Great Lakes wolf and the smaller being the Algonquin wolf. The eastern wolf's morphology is midway between that of the northwestern wolf and the coyote. The fur is typically of a grizzled grayish-brown color mixed with cinnamon. The nape, shoulder and tail region are a mix of black and gray, with the flanks and chest being rufous or creamy. It primarily preys on white-tailed deer, but may occasionally attack moose and beavers.In the third edition of Mammal Species of the World published in 2005, the mammalogist W. Christopher Wozencraft listed the eastern wolf as a gray wolf subspecies, which supports its earlier classification based on morphology in three studies. This taxonomic classification has since been debated, with proposals based on DNA analyses that includes a gray wolf ecotype, a gray wolf with genetic introgression from the coyote, a gray wolf/coyote hybrid, a gray wolf/red wolf hybrid, the same species as the red wolf, or a separate species Canis lycaon. Commencing in 2016, two studies using whole genome sequencing indicate that North American gray wolves and wolf-like canids were the result of ancient and complex gray wolf and coyote mixing, with the Great Lakes wolf possessing 25% coyote ancestry and the Algonquin wolf possessing 40% coyote ancestry.In the US, a bill is before Congress to remove protections under the Endangered Species Act of 1973 for the gray wolf populations located in the western Great Lakes region. In Canada, the eastern wolf is listed as Canis lupus lycaon under the Species At Risk Act 2002, Schedule 1 - List of Wildlife at Risk. In 2015, the Committee on the Status of Endangered Wildlife in Canada recognized the eastern wolf as Canis cf. lycaon (Canis species believed to be lycaon) and a threatened species worthy of conservation. The main threat to this wolf is human hunting and trapping outside of the protected areas, which leads to genetic introgression with the Eastern coyote due to a lack of mates. Further human development immediately outside of the protected areas and the negative public perception of wolves are expected to inhibit any further expansion of their range. In 2016, the Committee on the Status of Species at Risk in Ontario recognized the Algonquin wolf as a Canis sp. (Canis species) differentiated from the hybrid Great Lakes wolves and was the result of "hybridization and backcrossing among Eastern Wolf (Canis lycaon) (aka C. lupus lycaon), Gray Wolf (C. lupus), and Coyote (C. latrans)".

Göte Turesson

Göte Wilhelm Turesson (6 April 1892 – 30 December 1970) was a Swedish evolutionary botanist who made significant contributions to ecological genetics, and coined the terms ecotype and agamospecies. He conducted extensive work to demonstrate that there is a genetic basis to the differentiation of plant populations. This work stood in sharp contrast to most researchers at the time, who believed that the differentiation of plant populations was due to phenotypic plasticity. Further, Turesson came to the conclusion that differentiation of plant populations was largely driven by natural selection. His work on locally adapted plant populations led him to coin the term "ecotype" in 1922.

Henry M. Jackson Wilderness

The Henry M. Jackson Wilderness is a 103,297-acre (41,803 ha) designated wilderness area in the state of Washington, United States. The area lies adjacent to the southwest corner of the Glacier Peak Wilderness, northwest of Stevens Pass on U.S. Highway 2 and northeast of the town of Skykomish, Washington. Wild Sky Wilderness is located immediately southwest of the Henry M. Jackson Wilderness. While the wilderness straddles the Cascade Mountain Range, most of it is in the westside ecotype. The wilderness lies in parts of Snoqualmie, Mount Baker, and Wenatchee national forests.

Liriodendron tulipifera

Liriodendron tulipifera—known as the tulip tree, American tulip tree, tulipwood, tuliptree, tulip poplar, whitewood, fiddletree, and yellow-poplar—is the North American representative of the two-species genus Liriodendron (the other member is Liriodendron chinense), and the tallest eastern hardwood. It is native to eastern North America from Southern Ontario and Illinois eastward to southeastern Massachusetts and Rhode Island, and south to central Florida and Louisiana. It can grow to more than 50 m (160 ft) in virgin cove forests of the Appalachian Mountains, often with no limbs until it reaches 25–30 m (80–100 ft) in height, making it a very valuable timber tree.

It is fast-growing, without the common problems of weak wood strength and short lifespan often seen in fast-growing species. April marks the start of the flowering period in the Southern United States (except as noted below); trees at the northern limit of cultivation begin to flower in June. The flowers are pale green or yellow (rarely white), with an orange band on the tepals; they yield large quantities of nectar. The tulip tree is the state tree of Indiana, Kentucky, and Tennessee.

List of water buffalo breeds

This is a list of domestic water buffalo breeds and their uses.

Migratory woodland caribou

The migratory woodland caribou refers to two herds of Rangifer tarandus (known as caribou in North America) that are included in the migratory woodland ecotype of the subspecies Rangifer tarandus caribou or woodland caribou that live in Nunavik, Québec, and Labrador: the Leaf River caribou herd (LRCH) and the George River caribou herd (GRCH) south of Ungava Bay. Rangifer tarandus caribou is further divided into three ecotypes: the migratory barren-ground ecotype, the mountain ecotype or woodland (montane) and the forest-dwelling ecotype (boreal woodland caribou). According to researchers, the "George River herd which morphologically and genetically belong to the woodland caribou subspecies, at one time represented the largest caribou herd in the world and migrating thousands of kilometres from boreal forest to open tundra, where most females calve within a three-week period. This behaviour is more like barren-ground caribou subspecies." They argued that "understanding ecotype in relation to existing ecological constraints and releases may be more important than the taxonomic relationships between populations." The migratory George River caribou herd travel thousands of kilometres moving from wintering grounds to calving grounds near the Inuit hamlet of Kangiqsualujjuaq, Nunavik (also known as George River hamlet). In Nunavik and Labrador, the caribou population varies considerably with their numbers peaking in the later decades of each of the 18th, 19th and 20th centuries. In 1984, about 10,000 caribou of the George River herd drowned during their bi-annual crossing of the Caniapiscau River during the James Bay Hydro Project flooding operation. The most recent decline at the turn of the 20th century caused much hardship for the Inuit and Cree communities of Nunavik, who hunt them for subsistence.While the woodland caribou, Rangifer tarandus caribou (boreal population), boreal woodland caribou or boreal caribou, which is mainly sedentary, was assessed in May 2002 as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), not all herds and populations are endangered. For example, the Gros Morne National Park sedentary herd in insular Newfoundland is not endangered.

Neal Smith National Wildlife Refuge

The Neal Smith National Wildlife Refuge is a federal national wildlife refuge located in Jasper County, Iowa, United States. The refuge, formerly known as Walnut Creek, is named after Congressman Neal Edward Smith, who championed its creation. It seeks to restore the tallgrass prairie and oak savanna ecosystems that once covered most of Iowa. It has a herd of approximately 50 buffalo (bison) and 20 elk.

The core of the Neal Smith refuge was a 3,600-acre (1,500 ha) block of land originally acquired by Iowa Power and Light (now part of MidAmerican Energy) for a nuclear power plant. The Fish and Wildlife Service was able to acquire this land in 1990. Today the U.S. Fish and Wildlife Service has acquired about 6,000 acres much more of the allocated 11,865 acres (4,802 ha).

Although the Neal Smith refuge includes a patchwork of small and seriously degraded native prairies, most of the refuge is the result of prairie restoration or reconstruction efforts. The restoration work has been done with local ecotype seed harvested from nearby native prairie remnants or from other restoration efforts that have used acceptable local ecotype seed.

Pomodorino di Manduria

Pomodorino di Manduria (Little Tomato of Manduria) is an ecotype of tomato typical of Manduria, a city in the province of Taranto. In the local dialect, it is also called Pummitori paisano.

Timema

Timema is a genus of relatively short-bodied, stout stick insects native to the far western United States. The genus was first described in 1895 by Samuel Hubbard Scudder, based on observations of the species Timema californicum.Compared to other stick insects (order Phasmatodea), the genus Timema is considered basal; that is, the earliest "branch" to diverge from the phylogenetic tree that includes all Phasmatodea. To emphasize this outgroup status, all stick insects not included in Timema are sometimes described as "Euphasmatodea."

Five of the twenty-one species of Timema are parthenogenetic, including two species that have not engaged in sexual reproduction for one million years, the longest known asexual period for any insect.

Tyge W. Böcher

Tyge Wittrock Böcher (25 October 1909 – 15 March 1983) was a Danish botanist, evolutionary biologist, plant ecologist and phytogeographer.

He was born in Copenhagen to physician Einar Böcher and wife Cathinca née Andersen. Steen B. Böcher, professor of geography, was his brother.

Tyge Böcher was professor of botany at the University of Copenhagen from 1954 to 1979. He was a prolific scientific writer, leaving some 250 scholarly books and articles. His scientific research covered as diverse phylogenetic lineages as vascular plants, bryophytes, lichens and algae and a broad set of disciplines from anatomy, ecology and evolution of plant species to the ecology of plant populations and plant communities. He was particularly interested in chromosomal and ecological races of plant species. He did field work in Greenland, Denmark, various European mountain regions and in Argentina. His investigation of the Greenland flora were particularly ground-breaking.

He was a co-founder of Flora Europaea and he authored the Flora of Greenland (1968).

The genus Boechera Á.Löve & D.Löve is named after him.

Wood bison

The wood bison (Bison bison athabascae) or mountain bison (often called the wood buffalo or mountain buffalo), is a distinct northern subspecies or ecotype of the American bison. Its original range included much of the boreal forest regions of Alaska, Yukon, western Northwest Territories, northeastern British Columbia, northern Alberta, and northwestern Saskatchewan.

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