- Related Topics:
- natural selection
group selection
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What is biology?
Biology is the study of living things and their vital processes, examining the physicochemical aspects of life.
Group selection is a type of natural selection that acts on all members of a group collectively. In group selection, traits evolve based on the fitness of the group, where fitness means survival and reproductive success. The group typically consists of a small, cohesive social unit where members display altruistic behaviors, such as cooperative hunting, raising young, and warning systems.
Group selection has been a controversial topic since Charles Darwin introduced it in the 19th century. Selfless behaviors can jeopardize an individual's fitness, which lowers their chances of producing offspring. The study of group selection has played a significant role in informing other selection theories and has revealed insights into altruistic behaviors observed in animals and humans.
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What are living organisms?
Living organisms are complex systems capable of functions like metabolism, excretion, growth, reproduction, and response to stimuli. They contain hereditary information coded in nucleic acids and use protein catalysts called enzymes to control chemical reactions.
Group selection, a type of natural selection in biology, acts collectively on a group's members, influencing traits based on the group's fitness. Altruistic behaviors like cooperative hunting, raising young, and warning systems can influence group selection. This concept, though debated, highlights the importance of altruism in animal behavior and multilevel selection, where the most altruistic groups have greater reproductive success, fueling altruism within the population.
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How do organisms grow, develop, and reproduce?
Group selection is a type of natural selection that acts on all members of a given group, where traits evolve based on the fitness of groups, impacting survival and reproductive success.
Typically, the group under selection is a small, cohesive social unit where members interact altruistically, such as cooperative hunting, raising young, and warning systems. Charles Darwin acknowledged that selfless behaviors jeopardize individual fitness, posing a challenge to his theory.
Group selection has been a controversial topic, with various perspectives on its significance compared to individual and gene-level selection. Some argue that individual interests outweigh group interests, while others suggest group selection can explain certain behaviors, especially human moral behavior.
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How do different living things interact with each other and their environment?
Living things interact in communities through relationships ranging from antagonistic to cooperative, impacting the species involved positively, negatively, or neutrally.
Group selection is a type of natural selection that acts collectively on a group's members, where traits evolve based on the group's survival and reproductive success. It considers altruistic interactions, like cooperative hunting, raising young, and predatory warning systems.
Initially controversial, group selection was debated, dismissed, and later reexamined as a factor in multilevel selection, where altruistic groups have greater reproductive success, fueling altruism within the population. The debates around group selection consider if selection occurs at the level of the individual, gene, or group.
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group selection, in biology, a type of natural selection that acts collectively on all members of a given group. Group selection may also be defined as selection in which traits evolve according to the fitness (survival and reproductive success) of groups or, mathematically, as selection in which overall group fitness is higher or lower than the mean of the individual members’ fitness values. Typically the group under selection is a small cohesive social unit, and members’ interactions are of an altruistic nature. Examples of behaviours that appear to influence group selection include cooperative hunting, such as among lions and other social carnivores; cooperative raising of young, such as in elephants; and systems of predatory warning, such as those used by prairie dogs and ground squirrels.
The study of group selection has played an important role in informing other theories of selection and has shed light on the significance of altruistic behaviours observed in animals, including humans. However, it has been controversial since its introduction in the 19th century by British naturalist Charles Darwin. Often, selfless behaviours jeopardize the acting individuals’ fitness, possibly lowering their chances for leaving behind offspring. Darwin realized that this presented a problem for his theory of natural selection, for which the bearing and survival of offspring was a vital determinant of evolutionary success.
In the early 20th century, Darwin’s observations of group behaviour were explored by others in studies that focused on the evolution of certain physical traits and behaviours that appear to benefit social groups. But toward the middle of that century, following the rise of neo-Darwinism, in which Darwin’s theory of natural selection was synthesized with genetics (the modern evolutionary synthesis), the idea that selection acted on groups was largely dismissed. Many evolutionary biologists agreed that adaptation through selection at the level of the individual and the gene was of greater consequence than selection at the group level.
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But in the 1960s, group selection reemerged with the publication of Animal Dispersion in Relation to Social Behaviour (1962), a work by British zoologist V.C. Wynne-Edwards. Wynne-Edwards argued that individual subordination of selfish interests to promote group well-being could not be explained by individual selection. This was particularly so, he believed, for altruistic behaviours such as cooperative breeding, which restricts the dispersal of individual helpers, potentially limiting their reproductive success. According to Wynne-Edwards, this limitation ultimately meant that group selection functioned to keep populations in check, safeguarding them against excessive growth by influencing the evolution of species’ reproductive rates. Wynne-Edwards’s idea, however, contradicted emerging ideas associated with the neo-Darwinian synthesis, and many of his examples were based on individuals or on noncohesive groups. His idea was attacked by various proponents of individual selection and gene selection, including British ornithologist David Lack, American evolutionary biologist George C. Williams, and British evolutionary biologist Richard Dawkins. Several decades later, however, group selection found renewed interest in evolutionary thinking—namely, as a factor in multilevel selection, the idea that the most altruistic groups within a population enjoy the greatest reproductive success and thereby fuel the evolution of altruism within the population.