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Ecotype
Ecotypes are organisms which belong to the same species but possess different phenotypical features as a result of environmental factors such as elevation, climate and predation. Ecotypes can be seen in wide geographical distributions and may eventually lead to speciation. Definition In evolutionary ecology, an ecotype,Greek: ''οίκος'' = home and ''τύπος'' = type, coined by Göte Turesson in 1922 sometimes called ecospecies, describes a genetically distinct geographic variety, Population biology, population, or Race (biology), race within a species, which is genotypically Adaptation, adapted to specific environmental conditions. Typically, though ecotypes exhibit Phenotype, phenotypic differences (such as in Morphology (biology), morphology or physiology) stemming from environmental heterogeneity, they are capable of interbreeding with other geographically adjacent ecotypes without loss of fertility or vigor.''Ecology: From individuals to ecosystems'' by Begon, Townsen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological properties, and its behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code (its genotype) and the influence of environmental factors. Both factors may interact, further affecting the phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and again in his 1982 book '' The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as caddisfly larva cases and beaver dams ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boreal Woodland Caribou
The boreal woodland caribou (''Rangifer tarandus caribou''; but subject to a recent taxonomic revision. See Reindeer: Taxonomy), also known as Eastern woodland caribou, boreal forest caribou and forest-dwelling caribou, is a North American subspecies of reindeer (or caribou in North America) found primarily in Canada with small populations in the United States. Unlike the Porcupine caribou and barren-ground caribou, boreal woodland caribou are primarily (but not always) sedentary.In their 2012 report entitled "Recovery Strategy for the Woodland Caribou (Rangifer tarandus caribou), Boreal population, in Canada", Environment Canada and SARA refer to the woodland caribou as "boreal caribou". "Woodland Caribou (''Rangifer tarandus caribou''), Boreal population herein referred to as "boreal caribou", assessed in May 2002 as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). The boreal woodland caribou is the third largest of the caribou ecotypes aft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reindeer
The reindeer or caribou (''Rangifer tarandus'') is a species of deer with circumpolar distribution, native to Arctic, subarctic, tundra, taiga, boreal, and mountainous regions of Northern Europe, Siberia, and North America. It is the only representative of the genus ''Rangifer''. More recent studies suggest the splitting of reindeer and caribou into six distinct species over their range. Reindeer occur in both Animal migration, migratory and wiktionary:sedentary#Adjective, sedentary populations, and their herd sizes vary greatly in different regions. The tundra subspecies are adapted for extreme cold, and some are adapted for long-distance migration. Reindeer vary greatly in size and color from the smallest, the Svalbard reindeer (''R.'' (''t.'') ''platyrhynchus''), to the largest, Osborn's caribou (''R. t. osborni''). Although reindeer are quite numerous, some species and subspecies are in decline and considered Vulnerable species, vulnerable. They are unique among deer (Ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caribou
The reindeer or caribou (''Rangifer tarandus'') is a species of deer with circumpolar distribution, native to Arctic, subarctic, tundra, boreal, and mountainous regions of Northern Europe, Siberia, and North America. It is the only representative of the genus ''Rangifer''. More recent studies suggest the splitting of reindeer and caribou into six distinct species over their range. Reindeer occur in both migratory and sedentary populations, and their herd sizes vary greatly in different regions. The tundra subspecies are adapted for extreme cold, and some are adapted for long-distance migration. Reindeer vary greatly in size and color from the smallest, the Svalbard reindeer (''R.'' (''t.'') ''platyrhynchus''), to the largest, Osborn's caribou (''R. t. osborni''). Although reindeer are quite numerous, some species and subspecies are in decline and considered vulnerable. They are unique among deer (Cervidae) in that females may have antlers, although the prevalence of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sympatric Speciation
Sympatric speciation is the evolution of a new species from a surviving Common descent, ancestral species while both continue to inhabit the same geographic region. In evolutionary biology and biogeography, ''sympatric'' and ''sympatry'' are terms referring to organisms whose Range (biology), ranges overlap so that they occur together at least in some places. If these organisms are closely related (e.g. sister species), such a distribution may be the result of sympatric speciation. Etymologically, sympatry is derived . The term was coined by Edward Bagnall Poulton in 1904, who explains the derivation. Sympatric speciation is one of three traditional geographic modes of speciation.Futuyma, D. J. 2001. ''Evolution'' (2nd edition). Sinauer Associates, Inc. Allopatric speciation is the evolution of species caused by the geographic isolation of two or more populations of a species. In this case, divergence is facilitated by the absence of gene flow. Parapatric speciation is the evolut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Race (biology)
In Taxonomy (biology), biological taxonomy, race is an informal group (taxonomy), informal Taxonomic rank, rank in the taxonomic hierarchy for which various definitions exist. Sometimes it is used to denote a level below that of subspecies, while at other times it is used as a synonym for subspecies. It has been used as a higher rank than Strain (biology), strain, with several strains making up one race. Races may be Genetics, genetically distinct populations of individuals within the same species, Republished without known revision several times since 1999, and originally published as: or they may be defined in other ways, e.g. geographically, or physiologically. Genetic isolate, Genetic isolation between races is not complete, but genetic differences may have accumulated that are not (yet) sufficient to separate species. The term is recognized by some, but not governed by any of Nomenclature code, the formal codes of biological nomenclature. Taxonomic units below the level o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bimodal Distribution
In statistics, a multimodal distribution is a probability distribution with more than one mode (i.e., more than one local peak of the distribution). These appear as distinct peaks (local maxima) in the probability density function, as shown in Figures 1 and 2. Categorical, continuous, and discrete data can all form multimodal distributions. Among univariate analyses, multimodal distributions are commonly bimodal. Terminology When the two modes are unequal the larger mode is known as the major mode and the other as the minor mode. The least frequent value between the modes is known as the antimode. The difference between the major and minor modes is known as the amplitude. In time series the major mode is called the acrophase and the antimode the batiphase. Galtung's classification Galtung introduced a classification system (AJUS) for distributions: *A: unimodal distribution – peak in the middle *J: unimodal – peak at either end *U: bimodal – peaks at both ends ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Littorina Saxatilis
''Littorina saxatilis'', common name the rough periwinkle, is a species of small sea snail, a marine (ocean), marine gastropod mollusc in the family Littorinidae, the winkles or periwinkles. First identified in the 1700s, it has been misidentified as a new species 112 times. Distribution This species is native to the shores of the North Atlantic Ocean, including Hudson Bay, Baffin Island, Greenland, and the Barents Sea, south along the American East Coast to Chesapeake Bay, and along the European coast to the Straits of Gibraltar. Only one population of this intertidal species occurred in the Mediterranean basin i.e., Venice lagoon. The Venice population represents the earliest confirmed introduction of an exotic species in the Mediterranean Sea. Abiotic environmental features such as salinity and water temperature have influenced the past and current distributions of this snail and limited its invasion of the Mediterranean Sea. This species has also been introduced to San Franci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tundra
In physical geography, a tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: #Arctic, Arctic, Alpine tundra, Alpine, and #Antarctic, Antarctic. Tundra vegetation is composed of dwarf shrubs, Cyperaceae, sedges, Poaceae, grasses, mosses, and lichens. Scattered trees grow in some tundra regions. The ecotone (or ecological boundary region) between the tundra and the forest is known as the tree line or timberline. The tundra soil is rich in nitrogen and phosphorus. The soil also contains large amounts of biomass and decomposed biomass that has been stored as methane and carbon dioxide in the permafrost, making the tundra soil a carbon sink. As global warming heats the ecosystem and causes soil thawing, the permafrost carbon cycle accelerates and releases much of these soil-contained greenhouse gases into the atmosphere, creating Climate change feedback, a feedback cycle t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Museum Of Canada
The national museums of Canada () are the nine museums in Canada designated under the federal ''Museums Act'' and operated by the Government of Canada. The national museums are responsible for "preserving and promoting the heritage of Canada and all its peoples" and serving as "a source of inspiration, research, learning and entertainment... in official bilingualism in Canada, both official languages." There are many other museums owned and operated by the Canadian federal government that are not considered national museums. The Bank of Canada Museum in Ottawa, Correctional Service of Canada Museum in Kingston, and the National Historic Sites of Canada operated by Parks Canada across the country are all examples of museums administered by federal agencies but outside the national museums system. History Origins The concept of a "National Museum" in Canada had its beginnings on 16 May 1856, when the government of the Province of Canada authorized the Geological Survey of Canada to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian Wildlife Service
The Canadian Wildlife Service or CWS (), is a Branch of the Department of Environment and Climate Change Canada, a department of the Government of Canada. Founded in 1947 as Dominion Wildlife Service, it is Canada's national wildlife agency responsible for the protection and management of migratory birds, endangered species and nationally important wildlife habitats. November 1, 2012 marked the 65th anniversary of the founding of Service (originally known as the Dominion Wildlife Service). CWS conducts scientific research and monitoring, develops policies and regulations, manages permits, and provides financial and technical support for conservation programs. It manages 54 national wildlife areas and 92 migratory bird sanctuaries across Canada and plays a key role in implementing federal legislation, such as the Migratory Birds Convention Act, the Endangered Species Act and the Canada Wildlife Act. The service works with provincial, territorial and indigenous governments as wel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a different organism is called a chimera. Hybrids are not always intermediates between their parents such as in blending inheritance (a now discredited theory in modern genetics by particulate inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridization, which include genetic and morph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
