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Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', which is when both biological sexes are phenotypically indistinguishable from each other. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 * 2-tuple, in mathematics and set theory * Ordered pair, 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 communications * Pair programming, an a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argus (bird)
An argus, or argus pheasant, is a member of a clade in the tribe Pavonini of the family Phasianidae, containing two species of bird that are closely related to peafowl. It has hundreds or thousands of tiny white spots on its plumage pattern, and thus its naming might have been in reference to the mythical hundred-eyed giant, Argus Panoptes. Two genera of birds are considered arguses: ''Rheinardia'' and '' Argusianus''. Within these genera there are a total of three recognized species. '' Argusianus'' has also been credited with a mysterious second species that is sometimes thought to have gone extinct, but this is most likely based on a simple genetic aberration in the established species. Both genera are thought to be sister taxa to one another, and are otherwise most closely related to the peafowl (genera '' Pavo'' and '' Afropavo''), and slightly more distantly to the genus '' Tropicoperdix.'' *Genus '' Argusianus'' Rafinesque, 1815 ** Great argus (''Argusianus argus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Sexual Characteristics
Secondary sex characteristics are features that appear during puberty in humans, and at sexual maturity in other animals. These characteristics are particularly evident in the sexually dimorphic phenotypic traits that distinguish the sexes of a species, but unlike the sex organs (primary sex characteristics), are not directly part of the reproductive system. Secondary sex characteristics are believed to be the product of sexual selection for traits which display fitness, giving an organism an advantage over its rivals in courtship and in aggressive interactions. Secondary sex characteristics include, for example, the manes of male lions, the bright facial and rump coloration of male mandrills, and horns in many goats and antelopes. These characteristics are believed to be produced by a positive feedback loop known as the Fisherian runaway produced by the secondary characteristic in one sex and the desire for that characteristic in the other sex. Male birds and fish of many s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aposematism
Aposematism is the Advertising in biology, advertising by an animal to potential predation, predators that it is not worth attacking or eating. This unprofitability may consist of any defences 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 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. A genuine aposematic signal that a species actually ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litoria Lesueuri
Lesueur's frog (''Ranoidea lesueuri'') is a species of ground-dwelling tree frog native to south-eastern Australia, from Sydney, New South Wales, 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 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Foundation Oikos. Since 2011, the editor-in-chief has been Dries Bonte of Ghent University. History The journal was established in 1949 as ''Oikos: Acta Oecologica Scandinavica'', together with the Nordic Foundation 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 1949–1975, a number of supplements were published at irregular intervals. Since 2007, the ''Oikos'' subject editors make nominations for the annual Per Brinck Oikos Award given to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immune Function
The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and 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 virus infections. Other basic immune mechanisms evolved in ancient plants and animals and remain in their modern descendants. These mechanisms include phagocytosis, antimicrobia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultraviolet
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), 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 and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack the energy to ionize atoms, it can cause chemical reactions and causes many substances to glow or fluoresce. Consequently, the chemical and biological effects of UV are greater than simple heating effects, and many practical applications of UV radiation derive from its interactions with organic molecules. Short-wave ultraviolet light damages DNA and sterilizes surfaces with which it comes into contac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as ... 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 o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. Animals derive zeaxanthin from a plant diet. Zeaxanthin is one of the two primary xanthophyll carotenoids contained within the ret ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lutein
Lutein (;"Lutein" . from ''luteus'' meaning "yellow") is a and one of 600 known naturally occurring s. Lutein is synthesized only by plants, and like other xanthophylls is found in high quantities in |
