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Varied Carpet Beetle
The varied carpet beetle (''Anthrenus verbasci'') is a 3 mm-long beetle belonging to the family Dermestidae. They are a common species, often considered a pest of domestic houses and, particularly, natural history museums, where the larvae may damage natural fibers and can damage carpets, furniture, clothing, and insect collections. ''A. verbasci'' was also the first insect to be shown to have an annual behavioral rhythm and to date remains a classic example of circannual cycles in animals. Description Adult ''A. verbasci'' range in length from . The body is rounded, almost spherical. The elytra and pronotum are covered in fine scales of different colours, creating an irregular pattern of white, brownish and yellowish patches on these features. The white scales are focussed along the lateral margins of the pronotum and on the elytra, where they form three bright, wavy transverse bands. In addition to these morphological features, their antennae are 11-segmented, with a ...
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Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern Taxonomy (biology), taxonomy". Many of his writings were in Latin; his name is rendered in Latin as and, after his 1761 ennoblement, as . Linnaeus was born in Råshult, the countryside of Småland, in southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his ' in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In ...
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Relative Humidity
Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation, dew, or fog to be present. Humidity depends on the temperature and pressure of the system of interest. The same amount of water vapor results in higher relative humidity in cool air than warm air. A related parameter is the dew point. The amount of water vapor needed to achieve saturation increases as the temperature increases. As the temperature of a parcel of air decreases it will eventually reach the saturation point without adding or losing water mass. The amount of water vapor contained within a parcel of air can vary significantly. For example, a parcel of air near saturation may contain 28 g of water per cubic metre of air at , but only 8 g of water per cubic metre of air at . Three primary measurements of humidity are widely employed: absolute, relative, and specific. A ...
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Zeitgeber
A zeitgeber () is any external or environmental cue that entrains or synchronizes an organism's biological rhythms, usually naturally occurring and serving to entrain to the Earth's 24-hour light/dark and 12-month cycles. History The term ' (; ) was first used by Jürgen Aschoff, one of the founders of the field of chronobiology. His work demonstrated the existence of endogenous (internal) biological clocks, which synchronize biological rhythms. In addition, he found that certain exogenous (external) cues, which he called zeitgeber, influence the timing of these internal clocks. Photic and nonphotic zeitgebers * Light (light is a more important zeitgeber than social interactions). * Atmospheric conditions * Medication * Temperature * Social interactions * Exercise * Eating/drinking patterns Circadian rhythms Any biological process in the body that repeats itself over a period of approximately 24 hours and maintains this rhythm in the absence of external stimuli is considered a ci ...
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Diapause
In animal dormancy, diapause is the delay in development in response to regular and recurring periods of adverse environmental conditions.Tauber, M.J., Tauber, C.A., Masaki, S. (1986) ''Seasonal Adaptations of Insects''. Oxford University Press It is a physiological state with very specific initiating and inhibiting conditions. The mechanism is a means of surviving predictable, unfavorable environmental conditions, such as temperature extremes, drought, or reduced food availability. Diapause is observed in all the life stages of arthropods, especially insects. Embryonic diapause, a somewhat similar phenomenon, occurs in over 130 species of mammals, possibly even in humans, and in the embryos of many of the oviparous species of fish in the order Cyprinodontiformes. Activity levels of diapausing stages can vary considerably among species. Diapause may occur in a completely immobile stage, such as the pupae and eggs, or it may occur in very active stages that undergo extensive mig ...
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Chitin
Chitin ( C8 H13 O5 N)n ( ) is a long-chain polymer of ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is probably the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chitin are produced each year in the biosphere. It is a primary component of cell walls in fungi (especially basidiomycetes and filamentous fungi), the exoskeletons of arthropods such as crustaceans and insects, the radulae, cephalopod beaks and gladii of molluscs and in some nematodes and diatoms. It is also synthesised by at least some fish and lissamphibians. Commercially, chitin is extracted from the shells of crabs, shrimps, shellfishes and lobsters, which are major by-products of the seafood industry. The structure of chitin is comparable to cellulose, forming crystalline nanofibrils or whiskers. It is functionally comparable to the protein keratin. Chitin has proved useful for several medicinal, industrial and biotechnological purpose ...
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Keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, horns, claws, hooves, and the outer layer of skin among vertebrates. Keratin also protects epithelial cells from damage or stress. Keratin is extremely insoluble in water and organic solvents. Keratin monomers assemble into bundles to form intermediate filaments, which are tough and form strong unmineralized epidermal appendages found in reptiles, birds, amphibians, and mammals. Excessive keratinization participate in fortification of certain tissues such as in horns of cattle and rhinos, and armadillos' osteoderm. The only other biological matter known to approximate the toughness of keratinized tissue is chitin. Keratin comes in two types, the primitive, softer forms found in all vertebrates and harder, derived forms found only among saur ...
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Neotropical Realm
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone. Definition In biogeography, the Neotropic or Neotropical realm is one of the eight terrestrial realms. This realm includes South America, Central America, the Caribbean islands, and southern North America. In Mexico, the Yucatán Peninsula and southern lowlands, and most of the east and west coastlines, including the southern tip of the Baja California Peninsula are Neotropical. In the United States southern Florida and coastal Central Florida are considered Neotropical. The realm also includes temperate southern South America. In contrast, the Neotropical Floristic Kingdom excludes southernmost South America, which instead is placed in the Antarctic kingdom. The Neotropic is delimited by similarities in fauna or flora. Its fauna and flora are distinct f ...
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North Asia
North Asia or Northern Asia, also referred to as Siberia, is the northern region of Asia, which is defined in geographical terms and is coextensive with the Asian part of Russia, and consists of three Russian regions east of the Ural Mountains: Ural, Siberia, and the Russian Far East. North Asia is bordered by the Arctic Ocean to its north; by Eastern Europe to its west; by Central and East Asia to its south; and by the Pacific Ocean and North America to its east. It covers an area of , or 8.8% of Earth's total land area; and is the largest subregion of Asia by area, but is also the least populated, with a population of around 33 million, accounting for merely 0.74% of Asia's population. Topographically, the region is dominated by the Eurasian Plate, except for its eastern part, which lies on the North American, Amurian, and Okhotsk Plates. It is divided by three major plains: the West Siberian Plain, Central Siberian Plateau, and Verhoyansk-Chukotka collision zone. The ...
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North Africa
North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in the west, to Egypt's Suez Canal. Varying sources limit it to the countries of Algeria, Libya, Morocco, and Tunisia, a region that was known by the French during colonial times as "''Afrique du Nord''" and is known by Arabs as the Maghreb ("West", ''The western part of Arab World''). The United Nations definition includes Morocco, Algeria, Tunisia, Libya, Egypt, Sudan, and the Western Sahara, the territory disputed between Morocco and the Sahrawi Republic. The African Union definition includes the Western Sahara and Mauritania but not Sudan. When used in the term Middle East and North Africa (MENA), it often refers only to the countries of the Maghreb. North Africa includes the Spanish cities of Ceuta and Melilla, and plazas de so ...
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Nearctic Realm
The Nearctic realm is one of the eight biogeographic realms constituting the Earth's land surface. 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 are Eastern Mexico, Southern Florida, coastal Central Florida, Central America, and the Caribbean islands, which, together with South America, are part of the Neotropical realm. Major ecological regions 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)." Canadian Shield 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 fl ...
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Near East
The ''Near East''; he, המזרח הקרוב; arc, ܕܢܚܐ ܩܪܒ; fa, خاور نزدیک, Xāvar-e nazdik; tr, Yakın Doğu is a geographical term which roughly encompasses a transcontinental region in Western Asia, that was once the historical Fertile Crescent, and later the Levant region. It also comprises Turkey (both Anatolia and East Thrace) and Egypt (mostly located in North Africa, with the Sinai Peninsula being in Asia). Despite having varying definitions within different academic circles, the term was originally applied to the maximum extent of the Ottoman Empire. According to the National Geographic Society, the terms ''Near East'' and ''Middle East'' denote the same territories and are "generally accepted as comprising the countries of the Arabian Peninsula, Cyprus, Egypt, Iraq, Iran, Israel, Jordan, Lebanon, Palestinian territories, Syria, and Turkey". In 1997, the Food and Agriculture Organization (FAO) of the United Nations defined the region similarly, bu ...
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Palearctic Realm
The Palearctic or Palaearctic is the largest of the eight biogeographic realms of the Earth. It stretches across all of Eurasia north of the foothills of the Himalayas, and North Africa. The realm consists of several bioregions: the Euro-Siberian region; the Mediterranean Basin; the Sahara and Arabian Deserts; and Western, Central and East Asia. The Palaearctic realm also has numerous rivers and lakes, forming several freshwater ecoregions. The term 'Palearctic' was first used in the 19th century, and is still in use as the basis for zoogeographic classification. History In an 1858 paper for the ''Proceedings of the Linnean Society'', British zoologist Philip Sclater first identified six terrestrial zoogeographic realms of the world: Palaearctic, Aethiopian/Afrotropic, Indian/Indomalayan, Australasian, Nearctic, and Neotropical. The six indicated general groupings of fauna, based on shared biogeography and large-scale geographic barriers to migration. Alfred Wall ...
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