Sexual Dimorphism
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Sexual Dimorphism
Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, dioecious species, which consist of most animals and some plants. Differences may include secondary sex characteristics, size, weight, color, markings, or behavioral or cognitive traits. Male-male reproductive competition has evolved a diverse array of sexually dimorphic traits. Aggressive utility traits such as "battle" teeth and blunt heads reinforced as battering rams are used as weapons in aggressive interactions between rivals. Passive displays such as ornamental feathering or song-calling have also evolved mainly through sexual selection. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', when both biological sexes are phenotype, ...
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Pair Of Mandarin Ducks
Pair or PAIR or Pairing may refer to: Government and politics * Pair (parliamentary convention), matching of members unable to attend, so as not to change the voting margin * ''Pair'', a member of the Prussian House of Lords * ''Pair'', the French equivalent of peer, holder of a French Pairie, a French high title roughly equivalent to a member of the British peerage Mathematics * 2 (number), two of something, a pair * Unordered pair, or pair set, in mathematics and set theory * Ordered pair, or 2-tuple, in mathematics and set theory * Pairing, in mathematics, an R-bilinear map of modules, where R is the underlying ring * Pair type, in programming languages and type theory, a product type with two component types * Topological pair, an inclusion of topological spaces Science and technology * Couple (app), formerly Pair, a mobile application for two people * PAIR (puncture-aspiration-injection-reaspiration), in medicine * Pairing, a handshaking process in Bluetooth communication ...
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Bird-of-paradise
The birds-of-paradise are members of the Family (biology), family Paradisaeidae of the order Passeriformes. The majority of species are found in eastern Indonesia, Papua New Guinea, and eastern Australia. The family has 45 species in 17 genera. The members of this family are perhaps best known for the plumage of the males of the species, the majority of which are sexually dimorphic. The males of these species tend to have very long, elaborate feathers extending from the beak, wings, tail, or head. For the most part, they are confined to dense rainforest habitats. The diet of all species is dominated by fruit and to a lesser extent arthropods. The birds-of-paradise have a variety of breeding systems, ranging from Monogamy in animals, monogamy to Lek (mating arena), lek-type Animal sexual behaviour#Polygamy, polygamy. A number of species are threatened by hunting and habitat loss. Taxonomy The family Paradisaeidae is introduced (as Paradiseidae) in 1825 with ''Paradisaea'' as the t ...
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Aposematism
Aposematism is the Advertising in biology, advertising by an animal, whether terrestrial or marine, to potential predation, predators that it is not worth attacking or eating. This unprofitability may consist of any defenses which make the prey difficult to kill and eat, such as toxicity, venom, foul taste or smell, sharp spines, or aggressive nature. These advertising signals may take the form of conspicuous animal coloration, coloration, sounds, odours, or other perception, perceivable characteristics. Aposematic Signalling theory, signals are beneficial for both predator and prey, since both avoid potential harm. The term was coined in 1877 by Edward Bagnall Poulton for Alfred Russel Wallace's concept of warning coloration. Aposematism is exploited in Müllerian mimicry, where species with strong defences evolve to resemble one another. By mimicking similarly coloured species, the warning signal to predators is shared, causing them to learn more quickly at less of a cost. ...
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Hyperolius Ocellatus
''Hyperolius ocellatus'' is a species of tropical West African frog in the family Hyperoliidae, that is split into the subspecies ''H. o. ocellatus'' and ''H. o. purpurescens''. It is found in Angola, Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Equatorial Guinea, Gabon, Nigeria, Uganda, and possibly Rwanda. Its natural habitats are subtropical or tropical moist lowland forests, rivers, intermittent freshwater marshes, freshwater springs, rural gardens, heavily degraded former forest, ponds, and canals and ditches. Distribution and habitat ''Hyperolius ocellatus ocellatus'' is from areas west of the Sanaga River in Cameroon, and ''H. o. purpurescens'' is found south and east of the river. Due to the high population of the species and the extended area in which it can be found, the International Union for Conservation of Nature have classed ''Hyperolius ocellatus'' as Least Concern, as its population is thought to be stable. It is u ...
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Litoria Lesueuri
Lesueur's frog (''Ranoidea lesueuri'') is a species of ground-dwelling tree frog native to south-eastern Australia, from Sydney, to eastern Victoria. Etymology The specific name, ''lesueuri'', is in honor of French naturalist Charles Alexandre Lesueur.Beoelens B, Watkins M, Grayson M. 2013. ''The Eponym Dictionary of Amphibians''. Exeter, England: Pelagic Publishing Ltd. xiii + 262 pp. . ("Lesueur", p. 124). Description Lesueur's frog is a moderately large frog; females of this species reach 7 cm (2.8 in), while males reach about 4.5 cm (1.8 in). It ranges from pale to dark brown above, but males in the breeding season become bright yellow. Often, darker patches occur on the back. A dark stripe runs from the snout to the shoulder. The backs of the legs are blue with black spots, which helps distinguish this species from the very similar stony creek frog. The top half of the iris is pale and the bottom half dark. The toe discs are small and the belly is whi ...
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Oikos (journal)
''Oikos'' is a monthly peer-reviewed scientific journal covering research in the field of ecology. It is published by Wiley-Blackwell on behalf of the Nordic Society Oikos. History The journal was established in 1949 as ''Oikos: Acta Oecologica Scandinavica'', together with the Nordic Society Oikos, to provide a vehicle for publishing in the growing field of ecology. The journal content would have no preference with regard to taxonomic group. In the 1970s, the scope was narrowed to studies with relevance to the progress of theory in ecology. From 1949 to 1977, the journal appeared in one volume of three issues per year. From 1977 to 1987, two volumes per year were produced, and three volumes from 1987. In addition, from 1949 to 1975, a number of supplements were published at irregular intervals. Per Brinck Oikos Award Between 2007 and 2014, the subject editors made nominations for an annual award given to a world-leading ecologist. The following persons have received this award ...
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Immune Function
The immune system is a network of biological systems that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to bacteria, as well as cancer cells, parasitic worms, and also objects such as wood splinters, distinguishing them from the organism's own healthy tissue. Many species have two major subsystems of the immune system. The innate immune system provides a preconfigured response to broad groups of situations and stimuli. The adaptive immune system provides a tailored response to each stimulus by learning to recognize molecules it has previously encountered. Both use molecules and cells to perform their functions. Nearly all organisms have some kind of immune system. Bacteria have a rudimentary immune system in the form of enzymes that protect against viral infections. Other basic immune mechanisms evolved in ancient plants and animals and remain in their modern descendants. These mechanisms include phagocytosis, antim ...
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Ultraviolet
Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs, Cherenkov radiation, and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. The photons of ultraviolet have greater energy than those of visible light, from about 3.1 to 12  electron volts, around the minimum energy required to ionize atoms. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack sufficient energy, it can induce chemical reactions and cause many substances to glow or fluoresce. Many practical applications, including chemical and biological effects, are derived from the way that UV radiation can interact with organic molecules. The ...
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Journal Of Zoology
The ''Journal of Zoology'' is a scientific journal concerning zoology, the study of animals. It was founded in 1830 by the Zoological Society of London and is published by Wiley-Blackwell. It carries original research papers, which are targeted towards general readers. Some of the articles are available via open access, depending on the author's wishes. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 2.322, ranking it 36th out of 175 journals in the category "Zoology". From around 1833, it was known as the ''Proceedings of the Zoological Society of London'' (). From 1965 to 1984, it was known as the ''Journal of Zoology: Proceedings of the Zoological Society of London'' (). See also * List ...
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Zeaxanthin
Zeaxanthin is one of the most common carotenoids in nature, and is used in the xanthophyll cycle. Synthesized in plants and some micro-organisms, it is the pigment that gives paprika (made from bell peppers), corn, saffron, goji ( wolfberries), and many other plants and microbes their characteristic color. The name (pronounced ''zee-uh-zan'-thin'') is derived from ''Zea mays'' (common yellow maize corn, in which zeaxanthin provides the primary yellow pigment), plus ''xanthos'', the Greek word for "yellow" (see xanthophyll). Xanthophylls such as zeaxanthin are found in highest quantity in the leaves of most green plants, where they act to modulate light energy and perhaps serve as a non-photochemical quenching agent to deal with triplet chlorophyll (an excited form of chlorophyll) which is overproduced at high light levels during photosynthesis. Zeaxanthin in guard cells acts as a blue light photoreceptor which mediates the stomatal opening. Animals derive zeaxanthin from ...
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Lutein
Lutein (;"Lutein"
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from ''luteus'' meaning "yellow") is a xanthophyll and one of 600 known naturally occurring carotenoids. Lutein is synthesized only by plants, and like other xanthophylls is found in high quantities in green le ...
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Carotenoid
Carotenoids () are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, canaries, flamingos, salmon, lobster, shrimp, and daffodils. Over 1,100 identified carotenoids can be further categorized into two classes xanthophylls (which contain oxygen) and carotenes (which are purely hydrocarbons and contain no oxygen). All are derivatives of tetraterpenes, meaning that they are produced from 8 isoprene units and contain 40 carbon atoms. In general, carotenoids absorb wavelengths ranging from 400 to 550 nanometers (violet to green light). This causes the compounds to be deeply colored yellow, orange, or red. Carotenoids are the dominant pigment in autumn leaf coloration of about 15-30% of tree species, but many plant colors, especially reds and purples, are due to polyphenols. Carotenoids serve two key roles in p ...
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