Group Selection

Applied to Evolving to Extinction by Ruben Bloom 4y ago
Applied to Group selection update by Ruben Bloom 4y ago

People who are unfamiliar with evolutionary theory sometimes proposeGroup Selection posits that a featurenatural selection might not operate at the level of genes in individuals, and instead also operate at genes in groups of individuals, i.e. selecting for genes for the group even at the expense of the organism is there for the good of the group - forindividual. For example, you might posit that human religion is an adaptation to make human groups more cohesive, since religious groups outfight nonreligious groups.

Postulating group selection is guaranteed to make professional evolutionary biologists roll up their eyes and sigh.See also:Evolution, Alienness of evolution

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Created by Eliezer Yudkowsky at 4y

Added by Phil Goetz: In contrast to what is written above, I note that:

  • The arguments presented above only argue against genetic group selection for altruism; and yet they are then used to dismiss cultural group selection for non-altruistic properties (for example, religion).
  • Species selection for altruistic-like traits has been found to occur in nature; see "Group selection update" below.
  • And yet, species selection is a kind of group selection; and most of the arguments against group selection apply against species selection.
  • The mathematical model cited above does not allow groups to be selected against, therefore it does not test group selection.
  • The historical record is full of examples of group-level cultural adaptation and selection in humans.
  • The arguments presented above only argue against genetic group selection for altruism; and yet they are then used to dismiss cultural group selection for non-altruistic properties (for example, religion).
  • Species selection for altruistic-like traits has been found to occur in nature; see "Group selection update" below.
  • And yet, species selection is a kind of group selection; and allmost of the arguments against group selection apply against species selection.
  • The mathematical model cited above does not allow groups to be selected against, therefore it does not test group selection.
  • The historical record is full of examples of group-level cultural adaptation and selection in humans.
  • The arguments presented above only argue against genetic group selection for altruism; and yet they are then used to dismiss cultural group selection for non-altruistic properties (for example, religion).
  • Species selection for altruistic-like traits has been found to occur in nature; see "Group selection update" below.
  • And yet, species selection is a kind of group selection; and all of the arguments against group selection apply against species selection.
  • The mathematical model cited above does not allow groups to be selected against, therefore it does not test group selection.
  • The historical record is full of examples of group-level cultural adaptation and selection in humans.

Added by Phil Goetz: In contrast to what is written above, I note that:

  • The arguments presented above only argue against group selection for altruism; and yet they are then used to dismiss group selection for non-altruistic properties (for example, religion).
  • Species selection for altruistic-like traits has been found to occur in nature; see "Group selection update" below.
  • And yet, species selection is a kind of group selection; and all of the arguments against group selection apply against species selection.
  • The mathematical model cited above does not allow groups to be selected against, therefore it does not test group selection.
  • The historical record is full of examples of group-level cultural adaptation and selection in humans.

The historical fiasco of group selectionism is relied on as a clear-cut(clear-cut) case in point of the dangers of anthropomorphism.

Yudkowsky usesThe historical fiasco of group selectionism asis a clear-cut case in point of the dangers of anthropomorphism.

People who are unfamiliar with evolutionary theory sometimes propose that a feature of the organism is there for the good of the group - for example, that human religion is an adaptation to make human groups more cohesive, and it survives becausecohesive, since religious groups outfight nonreligious groups.

To the best of mythis editor's knowledge, no definite example of a group-level adaptation has ever been observed in a mammalian species. Ever.

It seems to be extremely popular among a certain sort of amateur evolutionary theorist, though - there's a certain sort of person who, if they don't know about the incredible mathematical difficulty, will fall in love with speculationsfind it very satisfying to speculate about adaptations for the good of the group.

Yudkowsky uses group selectionism as a case in point of the dangers of anthropomorphism.

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People who are unfamiliar with evolutionary theory sometimes propose that a feature of the organism is there *forfor the good of the group*group - for example, that human religion is an adaptation to make human groups more cohesive, and it survives because religious groups outfight nonreligious groups.

People who are unfamiliar with evolutionary theory sometimes propose that a feature of the organism is there *for the good of the group* - for example, that human religion is an adaptation to make human groups more cohesive, and it survives because religious groups outfight nonreligious groups.

Postulating group selection is guaranteed to make professional evolutionary biologists roll up their eyes and sigh.

Consider two groups on different sides of a mountain: in group A, each mother gives birth to 2 males and 2 females; in group B, each mother gives birth to 3 females and 1 male. Group A and group B will have the same number of children, but group B will have 50% more grandchildren and 125% more great-grandchildren.

But consider: The rarer males become, the more reproductively valuable they become - not to the group, but to the individual parent. If all the females are doing what's good for the group and birthing 1 male per 10 females, then you can make a genetic killing by birthing all males, each of whom will have (on average) ten times as many grandchildren as their female cousins.

So while group selection ought to favor more girls, individual selection favors equal investment in male and female offspring. Just by looking at the statistics of a maternity ward, you can see that the quantitative balance between group selection forces and individual selection forces is overwhelmingly tilted in favor of individual selection in Homo sapiens.

Group selection is extremely hard to make work mathematically. In this simulation, for example, the cost to altruists is 3% of fitness, pure altruist groups have a fitness twice as great as pure selfish groups, the subpopulation size is 25, and 20% of all deaths are replaced with messengers from another group. The result is polymorphic for selfishness and altruism. If the subpopulation size is doubled to 50, selfishness is fixed. If the cost to altruists is increased to 6%, selfishness is fixed. If the altruistic benefit is decreased by half, selfishness is fixed or in large majority. Neighborhood-groups must be very small, with only around 5 members, for group selection to operate when the cost of altruism exceeds 10%.

To the best of my knowledge, no definite example of a group-level adaptation has ever been observed in a mammalian species. Ever.

Hence, postulating group selection in any species - let alone in humans - is guaranteed to make professional evolutionary biologists roll their eyes.

It seems to be extremely popular among a certain sort of amateur evolutionary theorist, though - there's a certain sort of person who, if they don't know about the incredible mathematical difficulty, will fall in love with speculations about adaptations for the good of the group.

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