altruistic behaviour
Quick Summary
Altruistic behavior in biology refers to actions that benefit others at a cost to oneself. This seemingly counterintuitive behavior can evolve through kin selection, a form of natural selection that considers the genetic fitness of relatives. The concept of inclusive fitness explains this: an individual's genetic success includes not only its own reproduction but also the reproduction of its relatives.
Hamilton's rule quantifies this, stating that altruism evolves when the benefit to the recipient (B), weighted by the genetic relatedness (r) between the altruist and recipient, exceeds the cost to the altruist (C). Essentially, genes promoting altruism can spread if they help copies of themselves in relatives reproduce more successfully than the altruist could on its own. Examples include parental care and alarm calls in social animals.12
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evolutionKin selection and reciprocal altruismThe apparent altruistic behaviour of many animals is, like some manifestations of sexual selection, a trait that at first seems incompatible with the theory of natural selection. Altruism is a form of behaviour that benefits other individuals at the expense of the one that performs the action;…
Read MoreThe apparent altruistic behaviour of many animals is, like some manifestations of sexual selection, a trait that at first seems incompatible with the theory of natural selection. Altruism is a form of behaviour that benefits other individuals at the expense of the one that performs the action;…
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kin selection…role in the evolution of altruism, cooperation, and sociality; however, the term kin selection was coined in 1964 by British evolutionary biologist Maynard Smith.
Read More…role in the evolution of altruism, cooperation, and sociality; however, the term kin selection was coined in 1964 by British evolutionary biologist Maynard Smith.
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- sociobiology
It explains apparently altruistic behaviour in some animal species as actually being genetically selfish, since such behaviours usually benefit closely related individuals whose genes resemble those of the altruistic individual. This insight helps explain why soldier ants sacrifice their lives in order to defend their colony, or why…
Read MoreIt explains apparently altruistic behaviour in some animal species as actually being genetically selfish, since such behaviours usually benefit closely related individuals whose genes resemble those of the altruistic individual. This insight helps explain why soldier ants sacrifice their lives in order to defend their colony, or why…
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E.O. WilsonThus, altruistic behaviour—as when an organism sacrifices itself in order to save other members of its immediate family—would seem incompatible with this process. In Sociobiology Wilson argued that the sacrifice involved in much altruistic behaviour results in saving closely related individuals—i.e., individuals who share many of…
Read MoreThus, altruistic behaviour—as when an organism sacrifices itself in order to save other members of its immediate family—would seem incompatible with this process. In Sociobiology Wilson argued that the sacrifice involved in much altruistic behaviour results in saving closely related individuals—i.e., individuals who share many of…
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animal social behaviorGeneral characteristicsof labor, cooperation, altruism, and a great many individuals aiding the reproduction of a relative few. The most widely recognized forms of social behavior, however, involve interaction within aggregations or groups of individuals. Social behaviors, their adaptive value, and their underlying mechanisms are of primary interest to scientists…
Read Moreof labor, cooperation, altruism, and a great many individuals aiding the reproduction of a relative few. The most widely recognized forms of social behavior, however, involve interaction within aggregations or groups of individuals. Social behaviors, their adaptive value, and their underlying mechanisms are of primary interest to scientists…
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animal social behaviorA historical perspective on the study of social behavior…workers, who believed that such altruism should rarely evolve, Wynne-Edwards’s advocacy of this view prompted a careful reappraisal of the evolutionary basis of social behavior that continues to this day.
Read More…workers, who believed that such altruism should rarely evolve, Wynne-Edwards’s advocacy of this view prompted a careful reappraisal of the evolutionary basis of social behavior that continues to this day.
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animal social behaviorThe ultimate causes of social behavior>altruism (the altruist makes a sacrifice and the recipient benefits), selfishness (the actor benefits at the expense of the recipient), and spite (the actor hurts the recipient and both pay a cost). Mutualistic associations pose no serious evolutionary difficulty since both individuals derive benefits that…
Read More>altruism (the altruist makes a sacrifice and the recipient benefits), selfishness (the actor benefits at the expense of the recipient), and spite (the actor hurts the recipient and both pay a cost). Mutualistic associations pose no serious evolutionary difficulty since both individuals derive benefits that…
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animal social behaviorThe ultimate causes of social behaviorA second solution for how altruism can evolve among unrelated individuals comes from a study in humans. In this study, individuals punished unrelated cheaters (altruistic punishment), even though they received no material benefit for doing so and were unlikely to interact with them in the future. Furthermore, there may be…
Read MoreA second solution for how altruism can evolve among unrelated individuals comes from a study in humans. In this study, individuals punished unrelated cheaters (altruistic punishment), even though they received no material benefit for doing so and were unlikely to interact with them in the future. Furthermore, there may be…
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