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Winner And Loser Effects
The winner and loser effect is an aggression phenomenon in which the winner effect is the increased probability that an animal will win future aggressive interactions after experiencing previous wins, while the loser effect is the increased probability that an animal will lose future aggressive interactions after experiencing previous losses. Overall these effects can either increase or decrease an animal's aggressive behaviour, depending on what effect affects the species of concern. Animals such as ''Agkistrodon contortrix'', Mangrove rivulus, ''Rivulus marmoratus'', and Blue-footed booby, ''Sula nebouxii'' show either both or one of these effects. The outcomes of winner and loser effects help develop and structure Hierarchy, hierarchies in nature and is used to support the game theory model of aggression. Causation A theory underlying the causation of the winner and loser effect deals with an animals perception on its own and other members resource holding potential. Essentia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mangrove Rivulus
The mangrove rivulus or mangrove killifish, ''Kryptolebias marmoratus'' (syn. ''Rivulus marmoratus''), is a species of killifish in the Family (biology), family Rivulidae. It lives in brackish and marine waters (less frequently in fresh water) along the coasts of Florida, through the Antilles, and along the eastern and northern Atlantic coasts of Mexico, Central America and South America (south to Brazil). It has a very wide tolerance of both salinity (0–68 ‰)Bester, CMangrove Rivulus.Florida Museum. Retrieved 6 May 2017. and temperature (),Hill, K Smithsonian Marine Station at Fort Pierce. Retrieved 6 May 2017. can survive for about two months on land, and mostly breeds by self-fertilization. It is typically found in areas with Rhizophora mangle, red mangrove and sometimes lives in burrows of ''Cardisoma guanhumi'' crabs. The mangrove rivulus is up to long, but most individuals are . Overall the mangrove rivulus is widespread and not threatened, but in the United States it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testosterone
Testosterone is the primary male sex hormone and androgen in Male, males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testicles and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of androgenic hair, body hair. It is associated with increased aggression, sex drive, Dominance hierarchy, dominance, courtship display, and a wide range of behavioral characteristics. In addition, testosterone in both sexes is involved in health and well-being, where it has a significant effect on overall mood, cognition, social and sexual behavior, metabolism and energy output, the cardiovascular system, and in the prevention of osteoporosis. Insufficient levels of testosterone in men may lead to abnormalities including frailty, accumulation of adipose fat tissue within the body, anxiety and depression, sexual performance issues, and bone loss. Excessiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winner And Loser Culture
A winner and loser culture is a culture which imagines many activities in society as a competition where one class of people are successful winners and another class are the losers who experience a lifestyle of failure. Characteristics Psychologist Oliver James described in a 1995 book how distribution of wealth results in some young people having more money for fortunate lives among a culture of winners while other young people are poor, surrounded by violence, and live in a culture where media and society describe much of what they do as loser culture. A 1997 socioeconomic study showed that a winner-loser culture encouraged violence in adolescents, with specific sociological emphasis on the role of violence. In part, findings reflected that juvenile violence is perpetrated by the presence of a winner-loser culture, which creates an " us against them" mindset that can lead to physical or verbal altercations. A 2005 sociological study of alcohol advertising examined the lifestyle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sula Nebouxii -Santa Cruz, Galapagos Islands, Ecuador-8 (1)
Sula may refer to: Places Norway * Sula Municipality, a municipality in Møre og Romsdal county * Sula, Møre og Romsdal, an island in Sula municipality, Møre og Romsdal county * Sula, Solund, an island in Solund municipality, Vestland county * Ytre Sula (Solund), an island in Solund municipality, Vestland county * Sula, Trøndelag, an island group in Frøya municipality, Trøndelag county * Indre Sula and Ytre Sula, two mountains in Surnadal municipality, Møre og Romsdal county Other locations * Sula, Iran, a village in Ardabil Province, Iran * Sula, Montana, a census-designated place in the United States * Sula Island, an island in the Philippines * Sula Islands, Indonesia ** Sula Islands Regency * Sula (Dnieper), a tributary of the Dnieper in Ukraine * Sula (Mezen), a tributary of the Mezen in northern Russia * Sula (Pechora), a tributary of the Pechora in northern Russia * Sula Sgeir, an island group in Scotland * San Pedro Sula, a city in Honduras * Sula Valley, a v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha (ethology)
In the zoological field of ethology, a dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social groups interact, creating a ranking system. Different types of interactions can result in dominance depending on the species, including ritualized displays of aggression or direct physical violence. In social living groups, members are likely to compete for access to limited resources and mating opportunities. Rather than fighting each time they meet, individuals of the same sex establish a relative rank, with higher-ranking individuals often gaining more access to resources and mates. Based on repetitive interactions, a social order is created that is subject to change each time a dominant animal is challenged by a subordinate one. Definitions Dominance is an individual's preferential access to resources over another based on coercive capacity based on strength, threat, and intimidation, com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Swordtail
The green swordtail (''Xiphophorus hellerii'') is a species of freshwater/brackish fish in family Poeciliidae of order Cyprinodontiformes. A live-bearer, it is closely related to the southern platyfish or 'platy' (''X. maculatus'') and can crossbreed with it. It is native to an area of North and Central America stretching from Veracruz, Mexico, to northwestern Honduras. Description The male green swordtail grows to a maximum overall length of and the female to . The name 'swordtail' is derived from the elongated lower lobe of the male's caudal fin (tailfin). Sexual dimorphism is moderate, with the female being larger than the male, but lacking the 'sword'. The wild form is olive green in color, with a red or brown lateral stripe and speckles on the dorsal and, sometimes, caudal fins. The male's 'sword' is yellow, edged in black below. Captive breeding has produced many color varieties, including black, red, and many patterns thereof, for the aquarium hobby. All varietie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xiphophorus Helleri 03
''Xiphophorus'' is a genus of euryhaline and freshwater fishes in the family Poeciliidae of order Cyprinodontiformes, native to Mexico and northern Central America. ''Xiphophorus'' species can be divided into three groups based on their evolutionary relationships: platyfish (or platies), northern swordtails, and southern swordtails. Platyfish formerly were classified in another genus, ''Platypoecilus'', which is now obsolete. The type species is ''X. hellerii,'' the green swordtail. Like most other new world Poeciliids, platies and swordtails are live-bearers that use internal fertilization and give birth to live young instead of laying eggs like the bulk of the world's fishes. The name ''Xiphophorus'' derives from the Greek words ξίφος (dagger) and φόρος (bearer), referring to the gonopodium on the males. All are relatively small fishes, which reach a maximum length of depending on the exact species involved. Distribution and conservation status The various ''Xi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corticosterone
Corticosterone, also known as 17-deoxycortisol and 11β,21-dihydroxyprogesterone, is a 21-carbon steroid hormone of the corticosteroid type produced in the cortex of the adrenal glands. In the very rare case of congenital adrenal hyperplasia due to 17α-hydroxylase deficiency cortisol production is blocked. Roles In many species, including amphibians, reptiles, rodents and birds, corticosterone is a main glucocorticoid, involved in regulation of energy, immune reactions, and stress responses. However, in humans, cortisol is the primary glucocorticoid that is produced primarily in the zona fasciculata of the adrenal cortex. Corticosterone has only weak glucocorticoid and mineralocorticoid potencies in humans and is important mainly as an intermediate in the steroidogenic pathway from pregnenolone to aldosterone. Corticosterone is converted to aldosterone by aldosterone synthase, found only in the mitochondria of glomerulosa cells. Glomerulosa cells are found in the zon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agkistrodon Contortrix
The eastern copperhead (''Agkistrodon contortrix''), also known simply as the copperhead, is a widespread species of venomous snake, a pit viper, endemic to eastern North America; it is a member of the subfamily Crotalinae in the Family (biology), family Viperidae. The eastern copperhead has distinctive, dark brown, hourglass-shaped markings, overlaid on a light reddish brown or brown/gray background. The body type is heavy, rather than slender. Neonates are born with green or yellow tail tips, which progress to a darker brown or black within one year. Adults grow to a typical length (including tail) of . In most of North America, the eastern copperhead favors Deciduous, deciduous forest and mixed woodlands. It may occupy rock outcroppings and ledges, but is also found in low-lying, swampy regions. During the winter, it hibernates in dens or limestone crevices, often together with timber rattlesnakes and black rat snakes. The eastern copperhead is known to feed on a wide variety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionarily Stable Strategy
An evolutionarily stable strategy (ESS) is a strategy (or set of strategies) that is ''impermeable'' when adopted by a population in adaptation to a specific environment, that is to say it cannot be displaced by an alternative strategy (or set of strategies) which may be novel or initially rare. Introduced by John Maynard Smith and George R. Price in 1972/3, it is an important concept in behavioural ecology, evolutionary psychology, mathematical game theory and economics, with applications in other fields such as anthropology, philosophy and political science. In game-theoretical terms, an ESS is an equilibrium refinement of the Nash equilibrium, being a Nash equilibrium that is also "evolutionarily stable." Thus, once fixed in a population, natural selection alone is sufficient to prevent alternative ( mutant) strategies from replacing it (although this does not preclude the possibility that a better strategy, or set of strategies, will emerge in response to selective press ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fitness (biology)
Fitness (often denoted w or ω in population genetics models) is a quantitative representation of individual reproductive success. It is also equal to the average contribution to the gene pool of the next generation, made by the same individuals of the specified genotype or phenotype. Fitness can be defined either with respect to a genotype or to a phenotype in a given environment or time. The fitness of a genotype is manifested through its phenotype, which is also affected by the developmental environment. The fitness of a given phenotype can also be different in different selective environments. With asexual reproduction, it is sufficient to assign fitnesses to genotypes. With sexual reproduction, recombination scrambles alleles into different genotypes every generation; in this case, fitness values can be assigned to alleles by averaging over possible genetic backgrounds. Natural selection tends to make alleles with higher fitness more common over time, resulting in Darwini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
