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Ecological Niche
In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for example, by growing when resources are abundant, and when predators, parasites and pathogens are scarce) and how it in turn alters those same factors (for example, limiting access to resources by other organisms, acting as a food source for predators and a consumer of prey). "The type and number of variables comprising the dimensions of an environmental niche vary from one species to another ndthe relative importance of particular environmental variables for a species may vary according to the geographic and biotic contexts". See also Chapter 2: Concepts of niches, pp. 7 ''ff'' A Grinnellian niche is determined by the habitat in which a species lives and its accompanying behavioral adaptations. An Eltonian niche emphasizes that a sp ...
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Flightless Dung Beetle Circellium Bachuss, Addo Elephant National Park, South Africa
Flightless birds are birds that through evolution lost the ability to fly. There are over 60 extant species, including the well known ratites (ostriches, emu, cassowaries, rheas, and kiwi) and penguins. The smallest flightless bird is the Inaccessible Island rail (length 12.5 cm, weight 34.7 g). The largest (both heaviest and tallest) flightless bird, which is also the largest living bird, is the ostrich (2.7 m, 156 kg). Many domesticated birds, such as the domestic chicken and domestic duck, have lost the ability to fly for extended periods, although their ancestral species, the red junglefowl and mallard, respectively, are capable of extended flight. A few particularly bred birds, such as the Broad Breasted White turkey, have become totally flightless as a result of selective breeding; the birds were bred to grow massive breast meat that weighs too much for the bird's wings to support in flight. Flightlessness has evolved in many different birds independently, ...
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California Thrasher
The California thrasher (''Toxostoma redivivum'') is a large member of family Mimidae found primarily in chaparral habitat in California and Baja California. It is the only species of ''Toxostoma'' throughout most of its range.Cody, M. L. (2020). California Thrasher (''Toxostoma redivivum''), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.calthr.01 retrieved July 27, 2021 Taxonomy and systematics The California thrasher is closely related to the crissal thrasher (''Toxostoma crissale'') and LeConte's thrasher (''T. lecontei''), and the three may form a superspecies. It has two subspecies, the nominate ''T. r. redivivum'' and ''T. r. sonomae''. Description The California thrasher is about long and weighs up to ; it is the largest thrasher. It has a distinctive long, decurved beak and a long tail. It is generally deep grayish brown above with olive tones on the tail. It has a grayish buff sup ...
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United Kingdom Of Great Britain And Ireland
The United Kingdom of Great Britain and Ireland was a sovereign state in the British Isles that existed between 1801 and 1922, when it included all of Ireland. It was established by the Acts of Union 1800, which merged the Kingdom of Great Britain and the Kingdom of Ireland into a unified state. The establishment of the Irish Free State in 1922 led to the remainder later being renamed the United Kingdom of Great Britain and Northern Ireland in 1927. The United Kingdom, having financed the European coalition that defeated France during the Napoleonic Wars, developed a large Royal Navy that enabled the British Empire to become the foremost world power for the next century. For nearly a century from the final defeat of Napoleon following the Battle of Waterloo to the outbreak of World War I, Britain was almost continuously at peace with Great Powers. The most notable exception was the Crimean War with the Russian Empire, in which actual hostilities were relatively limit ...
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Charles Sutherland Elton
Charles Sutherland Elton (29 March 1900 – 1 May 1991) was an English zoologist and animal ecologist. He is associated with the development of population and community ecology, including studies of invasive organisms. Personal life Charles Sutherland Elton was born in Manchester, a son of the literary scholar Oliver Elton and the children's writer Letitia Maynard Elton (''née'' MacColl). He had an older brother, Geoffrey Elton, who died at 33, and to whom Charles Elton in many of his writings attributes his interest in scientific natural history. Charles Elton married the English poet Edith Joy Scovell in 1937, a first five-year marriage to Rose Montague having ended in amicable divorce. Charles and Joy had two children, Catherine Ingrid Buffonge MBE and Robert Elton. Professional life Charles Elton was educated at Liverpool College and Oxford University, from which he graduated in zoology in 1922, with a first in his field research project and a third in the exams, an ...
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Ecomorph
Ecomorphology or ecological morphology is the study of the relationship between the ecological role of an individual and its morphological adaptations. The term "morphological" here is in the anatomical context. Both the morphology and ecology exhibited by an organism are directly or indirectly influenced by their environment, and ecomorphology aims to identify the differences. Current research places emphasis on linking morphology and ecological niche by measuring the performance of traits (i.e. sprint speed, bite force, etc.) associated behaviours, and fitness outcomes of the relationships. Current ecomorphological research focuses on a functional approach and application to the science. A broadening of this field welcomes further research in the debate regarding differences between both the ecological and morphological makeup of an organism. Development of ecomorphology The roots of ecomorphology date back to the late 19th century.Bock, W. J. 1994. Concepts and methods in ec ...
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Habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as Biophysical environment, environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and light intensity. Biotic index, Biotic factors will include the availability of food and the presence or absence of Predation, predators. Every species has particular habitat requirements, with habitat generalist species able to thrive in a wide array of environmental conditions while habitat specialist species requiring a very limited set of factors to survive. The habitat of a species is not necessarily fou ...
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Adaptive Radiation
In evolutionary biology, adaptive radiation is a process in which organisms diversify rapidly from an ancestral species into a multitude of new forms, particularly when a change in the environment makes new resources available, alters biotic interactions or opens new environmental niches. Starting with a single ancestor, this process results in the speciation and phenotypic adaptation of an array of species exhibiting different morphological and physiological traits. The prototypical example of adaptive radiation is finch speciation on the Galapagos ("Darwin's finches"), but examples are known from around the world. Characteristics Four features can be used to identify an adaptive radiation: #A common ancestry of component species: specifically a ''recent'' ancestry. Note that this is not the same as a monophyly in which ''all'' descendants of a common ancestor are included. #A phenotype-environment correlation: a ''significant'' association between environments and the m ...
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Convergent Evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy. The recurrent evolution of flight is a classic example, as flying insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are ''analogous'', whereas '' homologous'' structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions. The opposite of convergence is divergent evolution, where related species evolve different traits. Convergent evolution is similar to para ...
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Greater Antilles
The Greater Antilles ( es, Grandes Antillas or Antillas Mayores; french: Grandes Antilles; ht, Gwo Zantiy; jam, Grieta hAntiliiz) is a grouping of the larger islands in the Caribbean Sea, including Cuba, Hispaniola, Puerto Rico, Jamaica, and the Cayman Islands. Six island states share the region of the Greater Antilles, with Haiti and the Dominican Republic sharing the island of Hispaniola. Together with the Lesser Antilles, they make up the Antilles. While most of the Greater Antilles consists of independent countries, Puerto Rico is an unincorporated territory of the United States, while the Cayman Islands are a British Overseas Territory. The largest island by area is Cuba, which extends to the western end of the island group. Puerto Rico lies on the eastern end, and the island of Hispaniola, the largest island by population, is located in the middle. Jamaica lies to the south of Cuba, while the Cayman Islands are located to the west. The state of Florida is the clos ...
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Anole
Dactyloidae are a family of lizards commonly known as anoles () and native to warmer parts of the Americas, ranging from southeastern United States to Paraguay. Instead of treating it as a family, some authorities prefer to treat it as a subfamily, Dactyloidae, of the family Iguanidae. In the past they were included in the family Polychrotidae together with ''Polychrus'' (bush anoles), but the latter genus is not closely related to the true anoles. Anoles are small to fairly large lizards, typically green or brownish, but their color varies depending on species and many can also change it. In most species at least the male has a dewlap, an often brightly colored flap of skin that extends from the throat/neck and is used in displays. Anoles share several characteristics with geckos, including details of the foot structure (for climbing) and the ability to voluntarily break off the tail (to escape predators), but they are only very distantly related, anoles being part of Iguania. ...
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Euphorbia
''Euphorbia'' is a very large and diverse genus of flowering plants, commonly called spurge, in the family Euphorbiaceae. "Euphorbia" is sometimes used in ordinary English to collectively refer to all members of Euphorbiaceae (in deference to the type genus), not just to members of the genus. Euphorbias range from tiny annual plants to large and long-lived trees. The genus has roughly 2,000 members, making it one of the largest genera of flowering plants. It also has one of the largest ranges of chromosome counts, along with ''Rumex'' and ''Senecio''. '' Euphorbia antiquorum'' is the type species for the genus ''Euphorbia''. It was first described by Carl Linnaeus in 1753 in ''Species Plantarum''. Some euphorbias are widely available commercially, such as poinsettias at Christmas. Some are commonly cultivated as ornamentals, or collected and highly valued for the aesthetic appearance of their unique floral structures, such as the crown of thorns plant ('' Euphorbia milii'' ...
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Cactus
A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Greek word (''káktos''), a name originally used by Theophrastus for a spiny plant whose identity is now not certain. Cacti occur in a wide range of shapes and sizes. Although some species live in quite humid environments, most cacti live in habitats subject to at least some drought. Many live in extremely dry environments, even being found in the Atacama Desert, one of the driest places on Earth. Because of this, cacti show many adaptations to conserve water. For example, almost all cacti are succulents, meaning they have thickened, fleshy parts adapted to store water. Unlike many other succulents, the stem is the only part of most cacti where this vital process takes place. Most species of cacti have lost true leaves, retaining only spin ...
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