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Cosmopolitan Distribution
In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The extreme opposite of a cosmopolitan species is an endemic one, being found only in a single geographical location. Qualification The caveat “in appropriate habitat” is used to qualify the term "cosmopolitan distribution", excluding in most instances polar regions, extreme altitudes, oceans, deserts, or small, isolated islands. For example, the housefly is highly cosmopolitan, yet is neither oceanic nor polar in its distribution. Related terms and concepts The term pandemism also is in use, but not all authors are consistent in the sense in which they use the term; some speak of pandemism mainly in referring to diseases and pandemics, and some as a term intermediate between endemism and cosmopolitanism, in effect regarding pandemism as su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orcinus Orca
The orca or killer whale (''Orcinus orca'') is a toothed whale belonging to the oceanic dolphin family, of which it is the largest member. It is the only extant species in the genus ''Orcinus'' and is recognizable by its black-and-white patterned body. A cosmopolitan species, orcas can be found in all of the world's oceans in a variety of marine environments, from Arctic and Antarctic regions to tropical seas. Orcas have a diverse diet, although individual populations often specialize in particular types of prey. Some feed exclusively on fish, while others hunt marine mammals such as seals and other species of dolphin. They have been known to attack baleen whale calves, and even adult whales. Orcas are apex predators, as they have no natural predators. They are highly social; some populations are composed of very stable matrilineal family groups (pods) which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviours, which are of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beekeeping
Beekeeping (or apiculture) is the maintenance of bee colonies, commonly in man-made beehives. Honey bees in the genus ''Apis (insect), Apis'' are the most-commonly-kept species but other honey-producing bees such as ''Melipona'' stingless bees are also kept. Beekeepers (or apiarists) keep bees to collect honey and other products of the hive: beeswax, propolis, bee pollen, and royal jelly. Pollination of crops, raising Queen bee, queens, and production of package bees for sale are other sources of beekeeping income. Bee hives are kept in an apiary or "bee yard". The keeping of bees by humans, primarily for honey production, began around 10,000 years ago. Georgia (country), Georgia is known as the "cradle of beekeeping" and the oldest honey ever found comes from that country. The 5,500-year-old honey was unearthed from the grave of a noblewoman during archaeological excavations in 2003 near the town Borjomi. Ceramic jars found in the grave contained several types of honey, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cline (biology)
In biology, a cline (from the Greek κλίνειν ''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 collection of traits; a single population can therefore have as many clines as it has traits, at least in principle. 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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larus
''Larus'' is a large genus of gulls with worldwide distribution (by far the greatest species diversity is in the Northern Hemisphere). Many of its species are abundant and well-known birds in their ranges. Until about 2005–2007, most gulls were placed in this genus, but this arrangement is now known to be polyphyletic, leading to the resurrection of the genera ''Ichthyaetus'', ''Chroicocephalus'', ''Leucophaeus'', and '' Hydrocoloeus'' (this last had been recognized more often than the other genera) for several species traditionally included in ''Larus''. They are in general medium to large birds, typically grey or white, often with black markings on their heads or wings. They have stout, longish bills and webbed feet. The taxonomy of the large gulls in the herring and lesser black-backed complex is very complicated, with different authorities recognising between two and eight species. Taxonomy The genus ''Larus'' was introduced in 1758 by the Swedish naturalist Carl L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ring Species
In biology, a ring species is a connected series of neighbouring populations, each of which interbreeds with closely sited related populations, but for which there exist at least two "end" populations in the series, which are too distantly related to interbreed, though there is a potential gene flow between each "linked" population and the next. Such non-breeding, though genetically connected, "end" populations may co-exist in the same region ( sympatry) thus closing a "ring". The German term , meaning a circle of races, is also used. Ring species represent speciation and have been cited as evidence of evolution. They illustrate what happens over time as populations genetically diverge, specifically because they represent, in living populations, what normally happens over time between long-deceased ancestor populations and living populations, in which the intermediates have become extinct. The evolutionary biologist Richard Dawkins remarks that ring species "are only showing us i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Tern
The Arctic tern (''Sterna paradisaea'') is a tern in the family Laridae. This bird has a circumpolar breeding distribution covering the Arctic and sub-Arctic regions of Europe (as far south as Brittany), Asia, and North America (as far south as Massachusetts). The species is strongly migratory, seeing two summers each year as it migrates along a convoluted route from its northern breeding grounds to the Antarctic coast for the southern summer and back again about six months later. Recent studies have shown average annual round-trip lengths of about for birds nesting in Iceland and Greenland and about for birds nesting in the Netherlands. These are by far the longest migrations known in the animal kingdom. The Arctic tern nests once every one to three years (depending on its mating cycle). Arctic terns are medium-sized birds. They have a length of and a wingspan of . They are mainly grey and white plumaged, with a red/orange beak and feet, white forehead, a black nape and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
House Sparrow
The house sparrow (''Passer domesticus'') is a bird of the Old World sparrow, sparrow family Passeridae, found in most parts of the world. It is a small bird that has a typical length of and a mass of . Females and young birds are coloured pale brown and grey, and males have brighter black, white, and brown markings. One of about 25 species in the genus ''Passer'', the house sparrow is native to most of Europe, the Mediterranean Basin, and a large part of Asia. Its intentional or accidental introduced species, introductions to many regions, including parts of Australasia, Africa, and the Americas, make it the most widely distributed wild bird. The house sparrow is strongly associated with human habitation, and can live in urban or rural settings. Though found in widely varied habitats and climates, it typically avoids extensive woodlands, grasslands, and deserts away from human development. It feeds mostly on the seeds of grains and weeds, but it is an opportunistic eater a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osprey
The osprey (''Pandion haliaetus''), , also called sea hawk, river hawk, and fish hawk, is a diurnal, fish-eating bird of prey with a cosmopolitan range. It is a large raptor reaching more than in length and across the wings. It is brown on the upperparts and predominantly greyish on the head and underparts. The osprey tolerates a wide variety of habitats, nesting in any location near a body of water providing an adequate food supply. It is found on all continents except Antarctica, although in South America it occurs only as a non-breeding migrant. As its other common names suggest, the osprey's diet consists almost exclusively of fish. It possesses specialised physical characteristics and exhibits unique behaviour to assist in hunting and catching prey. As a result of these unique characteristics, it has been given its own taxonomic genus, ''Pandion'', and family, Pandionidae. Taxonomy The osprey was described by Carl Linnaeus under the name ''Falco haliaeetus'' in hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
African Bee
The East African lowland honey bee (''Apis mellifera scutellata'') is a subspecies of the western honey bee. It is native to central, southern and eastern Africa, though at the southern extreme it is replaced by the Cape honey bee (''Apis mellifera capensis''). This subspecies has been determined to constitute one part of the ancestry of the Africanized bees (also known as "killer bees") spreading through North and South America. The introduction of the Cape honey bee into northern South Africa poses a threat to East African lowland honey bees. If a female worker from a Cape honey bee colony enters an East African lowland honey bee nest, she is not attacked, partly due to her resemblance to the East African lowland honey bee queen. As she is capable of parthenogenetic reproduction, she may begin laying eggs which hatch as "clones" of herself, which will also lay eggs, causing the parasitic ''A. m. capensis'' workers to increase in number. The death of the host colony results fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africanized Bee
The Africanized bee, also known as the Africanized honey bee and known colloquially as the "killer bee", is a hybrid of the western honey bee (''Apis mellifera''), produced originally by crossbreeding of the East African lowland honey bee (''A. m. scutellata'') with various European honey bee subspecies such as the Italian honey bee ('' A. m. ligustica'') and the Iberian honey bee ('' A. m. iberiensis''). The East African lowland honey bee was first introduced to Brazil in 1956 in an effort to increase honey production, but 26 swarms escaped quarantine in 1957. Since then, the hybrid has spread throughout South America and arrived in North America in 1985. Hives were found in south Texas in the United States in 1990. Africanized honey bees are typically much more defensive than other varieties of honey bees, and react to disturbances faster than European honey bees. They can chase a person a quarter of a mile (400 m); they have killed so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism (biology)
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative ''phenotypes'', in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Ford E.B. 1965. ''Genetic polymorphism''. Faber & Faber, London. Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variety (botany)
In botanical nomenclature, variety (abbreviated var.; in la, varietas) is a taxonomic rank below that of species and subspecies, but above that of form. As such, it gets a three-part infraspecific name. It is sometimes recommended that the subspecies rank should be used to recognize geographic distinctiveness, whereas the variety rank is appropriate if the taxon is seen throughout the geographic range of the species. Example The pincushion cactus, '' Escobaria vivipara'' (Nutt.) Buxb., is a wide-ranging variable species occurring from Canada to Mexico, and found throughout New Mexico below about . Nine varieties have been described. Where the varieties of the pincushion cactus meet, they intergrade. The variety ''Escobaria vivipara'' var. ''arizonica'' is from Arizona, while ''Escobaria vivipara'' var. ''neo-mexicana'' is from New Mexico. See also ''Capsicum annuum var. glabriusculum'' Definitions The term is defined in different ways by different authors. However, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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