The demise of group selection

48

In the nicest possible way and with great respect, could I make two suggestions to would-be commenters, based on past experience when this topic has come up-

  1. Please pause before offering your own common sense view. There are topics in science, of which this is one, where common sense is not a good guide. If it were, professional biologists would not have been arguing about it for five decades. There is a large back literature in which the likelihood is strong that whatever commonsense view you put forward has already been proposed and exhaustively discussed. As an analogy, common sense is notoriously misleading when we try to understand quantum mechanics. If you could do physics by common sense, we wouldn’t need physicists. To a lesser extent, something like the same thing applies here.

  2. Please note that Homo sapiens is a very peculiar species and probably not the best testbed for the theories under discussion. That is not to say that the theories under discussion will forever be irrelevant to human affairs. But the argument at hand is sufficiently difficult that it is worth trying to understand it and solve it, at least to begin with, without the additional complications that arise with human culture. It’s not a bad idea to think about lions or ants or acorn woodpeckers as your model animal when trying to get to grips with these evolutionary theories.

Richard


The idea that adaptations in organisms result from “group selection” (selection among groups that differentially bud off subgroups, with those having good “group traits” becoming more numerous), rather than from selection among genes themselves, usually within individuals, has undergone a bit of resurgence in popular culture. This is in stark contrast to the views of most evolutionary biologists, who see group selection as a logical possibility, but one that doesn’t easily work in theoretical models and, more important, has explained almost nothing about nature.  In contrast, the gene-centered view of evolution worked out by biologists like W. D. Hamilton, Robert Trivers, and John Maynard Smith, and popularized by Richard Dawkins, has been immensely fruitful.

I’ve posted a lot on the intellectual vacuity of group selection, particularly its failure to explain the evolution of traits like human altruism and cooperation (see, for example, here, here, and here). If you want an elegant and easily digestible explanation of the weaknesses of group selection, Steve Pinker has just published a nice essay on John Brockman’s Edge website, “The false allure of group selection.“  If you’re interested in seeing three smart biologists take group selection apart, there’s an excellent paper by West, Griffin, and Gardner (reference below), which you can download for free here (the paper is not too hard, and the meat extends from pp. 376, beginning at “Error 3: the new”, to p. 379, bottom of Table 2).

There are several reasons why group selection has waned in popularity among evolutionists:

-  Group selection is a fuzzy and nebulous concept that is far less coherent than is gene-level selection (see Pinker’s essay for an explanation)

-  As I said above, when group selection does work in theory, it can be shown to be mathematically equivalent to gene-level selection involving “inclusive fitness.”  But the group-selection scenarios are far more unwieldy, and are often so complex that they can’t be modeled. As West et al. note:

1.  “No group selection model has ever been constructed where the same result cannot be found with kin selection theory”.

2.  “The group selection approach has proved to be less useful than the kin selection approach.”

3.  “The application of group selection theory has led to much confusion and time wasting.” It is, as the authors say, “easy to misapply, leading to incorrect statements about how natural selection operates,” it is “not distinct from kin selection”, and it “often leads to the confusing redefinition of terms and the use of confusing jargon.”

-  There are formidable theoretical problems with many concepts of group selection.  These include the fact that individuals reproduce faster than groups, so that an adaptation that is good for groups (say, pure altruism, in which individuals sacrifice their reproduction through behaviors that bring no benefits to the genes producing such behaviors), won’t spread because the rate of propagation of groups is undermined by the evolutionary disadvantage of altruistic behaviors within groups (non-altruists, or “cheaters,” will replace the altruists since they get the benefits without the costs). In other words, altruistic groups may do better than non-altruistic ones, but that won’t produce species-wide altruism because non-altruists do better than altruists within groups—unless, of course, altruists aren’t “pure” altruists and their genes reap some benefit from the behavior, in which case it’s kin selection.

 

Written By: Jerry Coyne
continue to source article at whyevolutionistrue.wordpress.com

48 COMMENTS

  1. I note that the Guardian has an article on this, and in it, it says:

    [E.O.] Wilson writes, “making such lists is futile. If science depended on rhetoric and polls, we would still be burning objects with phlogiston [a mythical fire-like element] and navigating with geocentric maps.”

    This is untrue.  Science does depend on polls, particularly when a matter has been under debate for decades and some people won’t move on.  The way for the non-expert to judge which opinion is likely to be right is to, effectively, take a poll of scientists.  Indeed, to take a poll is the only scientific way for the non-expert to attempt to obtain the best sample of views. 

    Claims by those such as Wilson that they have the right view are pointless, and can be (or at least should be) ignored by the public until he has been proven right.

  2. I don’t understand your post Steve.  When you say that Science depends on polls, you appear to be saying that publication and review are synonymous with taking a poll?

    If so. it is my duty to tell you this is not the case.  When we speak of a consensus of scientific opinion we are describing a situation where there are no dissenting voices to a hypothesis.  But this may only mean that the hypothesis has been studied by too few, that examples of successful predictions remain rare or unqualified, or that data and results remain to be examined or repeated.

    The way for the non-expert to judge which opinion is likely to be right is to, effectively, take a poll of scientists.

    It is a way, certainly.  It is also the way favoured by politicians – who tend to also limit themselves to few sources.

    It is unfortunate that you didn’t provide a link to the Guardian E.O.Wilson column.

    Peace.

  3. When D. S. Wilson and Eliot Sober took Hamilton’s equation ( rB > C ) and removed the coefficient of relatedness  for ” some averaged effect ” I lost all common sense and became incensed. That is all group selection is; a confused rip off of kin selection and, as I have said before, a confusion of groupiness in humans for group selection in humans. 

  4.  “When we speak of a consensus of scientific opinion we are describing a situation where there are no dissenting voices to a hypothesis.”
    No.  What we mean by consensus is consensus, not unanimity.

    “If so. it is my duty to tell you this is not the case.”

    Duty can weigh heavily on the shoulders of those who feel it.  I apologise for having imposed such a burden.

    My point seemed clear.  Let me try and analogy.  For any given area of science in which there is some dissent (which is all of them), get a ping-pong ball to represent each scientist.  Now colour those ping-pong balls that represent the consensus view as, say, black, and those that represent dissenting views as, say, white.

    Now get a great big barrel.  Throw in all the ping-pong balls, and give it a big shake.  Pick out a few ping-pong balls.  What you have done is statistically sampled from scientific opinion.  The view that it is reasonable to take on some matter in which there is dissent is the view which is most represented in your sample.  

    You see, although it is true that science has in the past sometimes been changed by people who have been called silly, those people are hugely outnumbered by the number of people who have been called silly because their views are silly.  Going for the silly is not a good way to find out the truth.

     “It is unfortunate that you didn’t provide a link to the Guardian E.O.Wilson column.”

    I’m new to this new commenting system.  All you need to do is to go to the Guardian website.

  5. The Guardian article is here

    http://www.guardian.co.uk/scie

    If so. it is my duty to tell you this is not the case. When we speak of a consensus of scientific opinion we are describing a situation where there are no dissenting voices to a hypothesis. But this may only mean that the hypothesis has been studied by too few, that examples of successful predictions remain rare or unqualified, or that data and results remain to be examined or repeated.

    I would have thought that when you speak of a “scientific consensus” you mean that the subject has been studied by enough scientists to form a sensible opinion and that the overwhelming majority hold the sam opinion. That opinion is the “scientific consensus”.

    Most scientists will not have an opinion at all if they don’t have enough evidence to form one, data is rare, etc, etc. In that case the scientific consensus is “we don’t know yet”.

    Michael

  6. Moderator might wish to correct the part of the opener that has been duplicated.

    There is a little link at the bottom RHS of the article saying “Report a Problem”. I’ve no idea how long they have been doing this but I just noticed it the other day when  mod pointed it out. 

    I’ve reported the repeat but I forgot to report the font size change.

    Michael

  7. Steve Zara

     

    [E.O.] Wilson writes,… This is untrue.
     Science does depend on polls, particularly when a matter has been under
    debate for decades and some people won’t move on.  The way for the
    non-expert to judge which opinion is likely to be right is to, effectively,
    take a poll of scientists.  Indeed, to take a poll is the only scientific
    way for the non-expert to attempt to obtain the best sample of views.

     

    I’m so glad to see someone besides me making this
    point. Here’s a thing that bugs me about people who deny the scientific consensus
    on something (my main experience of it is with those who claim to fence-sit on
    anthropogenic climate change, or said being dangerous): you explain the
    evidence to them, they say the “against” arguments sounded just as convincing,
    you debunk them, they *still* insist their brains aren’t powerful enough for
    them to see which side makes more sense, but they won’t let you defer them to
    the consensus of smarter experts because they genuinely believe the phrase “argument
    from authority” referring to a fallacy means *all* arguments from authority are
    bad. It’s about whether the authority is spurious. If a celebrity’s diet sounds
    convincing because they say it worked for them, that’s spurious. If a chemist
    warns you it’s dangerous to drop caesium in a shower, that’s not spurious!

     

    Stephen_of_Wimbledon

     

    you appear to be saying that publication and
    review are synonymous with taking a poll?

     

    No, he’s not. Publication and review are how
    scientists make up their minds and a consensus forms, because they’re smart
    enough to do it properly, and reading the relevant material is their full-time
    gig. Lay people, who don’t have the education, time and (usually) intelligence
    for that, can only make up their minds a different way: it should be by looking
    at consensus.

     

    When we speak of a consensus of scientific
    opinion we are describing a situation where there are no dissenting voices to a
    hypothesis.

     

    No we’re not. It needs to be way more than a simple
    majority, to be sure; but asking for no dissenters, even among the relevant
    experts, let alone among the full set of “voices” (is that even limited to
    scientists?), is bull. Some scientists even question evolution, if only because
    creationists deliberately became scientists to make that technically true.
    Nobel Laureates in science are famous for believing utter nonsense, usually
    outside their own field. Ridiculous denial of ACC occurs even among some
    climatologists, if only because they’re in the pockets of fossil fuel
    industries. But none of this refutes any claims of consensuses.

     

    But this may only mean that… examples of
    successful predictions remain rare or unqualified, or that data and results
    remain to be examined or repeated.

     

    You’d have at least a few dissenting voices in that
    case. Or does your definition of dissenters only include those who are sure it’s
    false, rather than simply saying the evidence doesn’t convince them of its
    truth?

     

    It is also the way favoured by politicians -
    who tend to also limit themselves to few sources.

     

    Then don’t limit yourself to a few sources! Which
    means not taking your poll from the list of scientists quoted in that Guardian
    article. Look at the stances of scientific organisations. Look at discussions
    of consensus by some of the experts. Look at polls that have been taken as
    broadly as possible by scientists rather than politicians. Look for
    percentages. Look for it to be about the relevant experts rather than all
    sciences *per se*.

  8. With regard to RD’s statement, there is nothing more to be said on the subject; his is the last word.

    Many moons ago I read “On Agression” and “The Territorial Imperative”, both of which were based on the now defunct “group selection” idea, but I’ve since learnt better, thanks, mainly, to the teaching of one Richard Dawkins; for which I’m most greatful. 

  9. This is in stark contrast to the views of most evolutionary biologists, who see group selection as a logical possibility, but one that doesn’t easily work in theoretical models and, more important, has explained almost nothing about nature.

    I think it would save everyone a lot of time and effort if we all just acknowledged the inherent logical fallacy in “group selection”. Trying to model it is like trying to model “God” or “free will”, it’s a waste of time.

    Group selection is a fuzzy and nebulous concept that is far less coherent than is gene-level selection (see Pinker’s essay for an explanation)

  10.  Good comment, but I’d like to address the “appeal to authority” fallacy
    in a little more detail. The “spurious” criterion might be a little difficult to apply.

    The first thing I like to point out is that appeal to expertise is not a fallacy per se. Authority and expertise are not the same thing. Appealing to expertise is actually valid support for an argument.

    However, there are two parts to appealing to expertise:
    1. That the person has relevant expertise to the topic.
    2. The degree to which the position aligns with the consensus of experts in the field.

    If the expert is works exactly on the topic at hand and has for decades, and their position represents the unanimous consensus of every expert in that field, that’s pretty good support. That support gets reduced the less relevant the expertise and the less unanimous the agreement on the position in question. One might model such support as Support = R*C*P where R is their relevant expertise (0 = general public, 1 = top scientist in the field), C is the scientific consensus on that position (0 = none, 1 = unanimous), and P is the position that you are seeking to support.

    This gives two parts to the fallacy. Often the person isn’t an expert. For example, claiming a politician says evolution is wrong and therefore it shouldn’t be taught in school is an appeal to authority fallacy because their authority is unrelated to the topic. They have no relevant expertise and so R = 0, hence the argument has no weight.

    The second part of the fallacy is the the degree of consensus on the position put forward. So, for instance, on anthropogenic global warming being real and a problem, the consensus is somewhere in the 90+% of climate scientists. Let’s say 95%. That means appealing to a true expert (R=1) who thinks AGW is wrong only supports that position with about a 5% weight (C = 0.05). So, while valid, if somebody is relying on the fringe beliefs it isn’t a very strong argument to appeal to that fringe expert. The fallacy comes from overstating the support.

    Hence when somebody says you are making an “appeal to authority error” when talking about scientific consensus, that isn’t true. You are appealing to relevant expertise and strong consensus, which is valid. Appealing to somebody with little expertise with on a fringe position is what holds little weight (though not really zero weight).

    Ultimately, I don’t like to use the words “valid” or “fallacy” which imply binary categories. Really the support for or against a position using experts is a form of Bayesian weighting of probabilities based on available information.

  11. It isn’t an inherent logical fallacy. If group selection posits that groups are replicators, then it is in theory possible, but just so unlikely as to be practically impossible. If it treats groups as vehicles, it either entails a violation of Ockham’s razor (adding needless complication when things like kin selection and reciprocal altruism and their offshoots readily do the work at no extra cost) or an impossibility with no evidence to support it.

    On a side note, don’t you think the expert biologists would know better than you whether it’s a logical possibility or not? As RD points out, they have spent the better part of five decades arguing about it.

  12. I’m affraid I have to disagree.

    Any argument from authority is just that……an argument from authority. Whether one re-labels it as ‘expertise’ or not. And the simple fact is that the bulk of expert opinion is no guarantee that a hypothesis is correct. It is facts that decide science……no amount of expert opinion is a substitute.

    It is a sad fact of science that one can quote numerous cases where the experts have, quite simply, been wrong. Well…no….maybe its not sad as that process of fact overiding opinion is esentially what science is all about. One gets there in the end.

    A classic example is gamma ray bursts. All the expert opinion was that this phenomenon could not possibly be coming from outside our galaxy, because the energy required would violate Einstein’s theories. The scientific data ultimately showed the bulk consensus to be wrong…..after some revisions to physics.

    Now the point worth making here is that the experts were wrong precisely because they were experts and knew their current physics models. It was their very ‘expertise’ that caused them to come to a wrong consensus.

    A point well worth beaing in mind. If the science is actually wrong then by definition the bulk of expert opinion will be wrong !

    This and other examples are why ‘the bulk of scientific opinion’ has to be seen as just that….opinion. The reason the opinion matters so much with global warming is because of the consequences. In the case of group selection, I accept the bulk of opinion because those scientists know vastly more about the subject than I do. But as with all opinion it is provisional while awaiting a more substantive ‘fact’ rubber stamping….or ( as with evolution ) a good case that the ‘fact’ level of evidence already exists.

  13. “Please pause before offering your own common sense view. There are
    topics in science, of which this is one, where common sense is not a
    good guide. If it were, professional biologists would not have been
    arguing about it for five decades. There is a large back literature in
    which the likelihood is strong that whatever commonsense view you put
    forward has already been proposed and exhaustively discussed. As an
    analogy, common sense is notoriously misleading when we try to
    understand quantum mechanics. If you could do physics by common sense,
    we wouldn’t need physicists. To a lesser extent, something like the same
    thing applies here.”

    Bloody arrogant. You lost me.

  14. Exactly. Coyne even says as much in this article: “This is in stark contrast to the views of most evolutionary biologists, who see group selection as a logical possibility, but one that doesn’t easily work in theoretical models and, more important, has explained almost nothing about nature”

  15. Because I have noticed many similarities between the arguments for “group selection” and the arguments for “intelligent design” over the years. I think they are both based on similar flaws in reasoning. Consider how Gaia is almost like “God”.

  16. The reason those people were able to make significant contributions to science, despite their outsider status, was because their ideas were brand new. None of them were trying to wade into a decades old argument from a position of ignorance, which is what Richard is warning against.

  17. Darwin 2.0
     
     
    Darwin’s great insight was much maligned by the well meaning Herbert Spencer when he coined the phrase “Survival of the Fittest.” It conjures up the idea that only the biggest, most muscled, most virile, and most prolific animals will survive and pass on their traits. With this as a frame of reference, it leaves us scratching our heads over what to do with the altruistic, regurgitating vampire bat, the flamboyantly handicapped peacock and the sterile insect drone. The phrase immediately requires the listener to decide for himself what is “fit” and posits a value judgment on the animal in question that is subject to the whims of human bias. For a trait, like altruism, which poorly resonates with our cognitive template of only the fittest, most selfish surviving, we fall back on group selection or some such permutation when the reason for a trait’s evolution eludes our collective imagination in discerning a “just so” Darwinian tale. Even Darwin was not immune to the siren song of group selection.
     
    Group selection arises to explain individually unfit traits like altruism. With Spencer’s catch phrase jangling around in our brain, we are blinded to the idea that certain “malignant” appearing traits are actually beneficial. A cancer gene would certainly seem “unfit” but it also might prevent over crowding and actually benefit one’s offspring. The converse is true as well, that traits which improved survival so much that they would require parents to compete for scarce resources that might be better suited for their own offspring or their offspring’s offspring. It might be better for your next generation if you yourself were not so very fit.
     
    Though it might be absurd to contemplate, imagine an antelope that developed an adaptation in fast muscle twitchiness that allowed him to outrun any predatory species. This adaptation becomes established before the predators have time to catch up, selectively speaking. They begin to outcompete their slower brethren and push the limits of sustainability established heretofore, because fewer are dying from predation. Now along comes a prolonged drought or blight on their food resource. Those faster, more populous antelope are least likely to survive the drought because they will more quickly exhaust the limited food resources, leaving all (or at least a larger number than those without the trait) vulnerable to extinction. Those antelope in other regions that did not expand their population with fast twitched individuals will be more likely to survive the drought. Under some circumstances, less might indeed be more.
     
    Now of course there are holes in this scenario. But there is no doubt that our evolution has been routinely defined by dire calamity. We have had to evolve by and large to survive when our environment was at its least productive. Paradoxical adaptations might be able to flourish in the setting of punctuated abundance followed by extreme dearth in order to keep the gene number at a manageable level.
     
    It seems to me that natural selection works to establish a perfect number or ideal census for a gene’s number in a given environment. Too many copies of a gene, ensconced in too many vehicles ,is just as inefficient for gene propagation as too few, and subject to being out competed by those that are less prolific. While most recognize that selection operates to regulate the number of gene births by regulating estrous cycles, clutch sizes, etc, it is less obvious that natural selection should operate to regulate the number of deaths (or non births in the case of sterile insects) as well to keep the gene number at its most efficient.  This comes back to the idea of inclusive fitness, that an organism can develop traits that directly decrease his own fitness but indirectly improve his genetic fitness by promoting the health of his relatives. We should expect natural selection to reduce the number of genes in a population if it means improved survival of the one’s left behind. When traveling up hill, it is not unusual to take one step back for every two steps forward. Thus we should not be surprised that there are traits that are seemingly antithetical to Darwin’s grand idea and we certainly don’t need group selection to explain them.
     
    Once you come around to the idea that natural selection does not define” fitness “the same way Herbert Spencer (or most inquisitive, well meaning enthusiasts of evolution) does, then it is easier to see why we have evolved seemingly paradoxical traits, without having to fall back on group selection or esoteric mathematical maneuvering, opaque to those like me who are nonetheless curious about evolution and its paradoxes.
     
    Altruism, if it truly is maladaptive for the individual, may be an adaptation that keeps a gene at its ideal number for efficient offspring survival. Natural selection can curtail an individual’s lifespan or reproductive potential and still be effective at efficiently disseminating genes. (Another way of defining “inclusive fitness”)
     
    Perhaps the law of unintended consequences is in play. The trait that appears malevolent may just be misunderstood. We certainly don’t have to fall back on group or multi-level selection just because we don’t have the mental faculty or population statistics to come up with an answer for why a trait might be advantageous. It might be more fitting to replace “the survival of the fittest” with “the survival of one’s offspring to fecundity who are most fit, up to a point, and most serendipitous.”
     
    But you just can’t sink your teeth into that, now can you? Guess I won’t be anyone’s bulldog with that drivel. Dawkins’ yapping Bichon Frise maybe. Anyone?
     

  18. Reading the Pinker piece that Coyne refers to one point screamed out at me, and eventually Pinker pretty much said it.  We are not adapted to do what the group wants us to do.  But I, as a group member, am extraordinarily well adapted to put all kinds of social pressure on everyone else to do what is best for my group.  

    I know that I have just broken both of Richard’s commandments in 1 sentence.  I’ll pretend that it was a) to show how common sense ideas can cut both ways, and b) the danger in using Home Sapiens for case studies.

  19.  

    … don’t limit yourself to a few sources!

    I don’t.  Politicians do – the intelligent ones (no, really, there are some) would call it ‘expedient’.

    … does your definition of dissenters only include those who are sure it’s
    false, rather than simply saying the evidence doesn’t convince them of its
    truth?

    Demanding that consensus = unanimity of interpretation of all evidence used to support an hypothesis.  Wouldn’t that be setting the bar a bit … high?

    I’m still looking for the article – I’m a little time constrained.

    In the meantime: You appear to be falling into the same trap as Steve.  Lay people (non-scientists) need to approach the gathering of opinion on science by avoiding polls, because all polls are dependent on the question posed, and the people polled.

    Perhaps our use(s) of the word poll is confusing?

    In addition, understanding science means understanding the scientific method.  Consensus on a hypothesis is only reached when enough evidence (data) is gathered to support it.  Some can be persuaded by the initial data set, others when complementary or matching data is found and still others by the emergence of hypotheses based on the original.

    Relying on polls sets the results at a remove from the evidence – and this is certainly the case with the leading ‘authorities’ in group selection who appear to be intent on arguing from authority.

    Peace.

  20. Duty can weigh heavily on the shoulders of those who feel it.  I apologise for having imposed such a burden.

    Ah me (sigh).

    Ping pong balls – sort of … reading round the subject?

    I’m new to this new commenting system.

    Me too.  Not as easy as the last one.

    Peace.

  21. In this article Coyne says “This is in stark contrast to the views of most evolutionary biologists, who see group selection as a logical possibility, but one that doesn’t easily work in theoretical models” that seems to me to support what I and others have been saying in response to your point. It IS a Logical possibility, not something inherently contradictory the way God or dualism are. It’s just that when you work out the details of the models they either don’t work or they reduce to individual or kin selection.

  22.  Hi Steve,

    Found the Guardian article – understand the context now.

    If I may be allowed a teensy-weensy criticism; your use of the word poll set me off down the wrong track.

    You’re right, of course (how could I ever have doubted you!), science proceeds by consensus and the best way for the laity to understand the science position on any subject is to seek out that consensus.

    The key, of course, is that consensus is built on evidence.  Wilson, et al, are claiming that insects (mostly) provide the evidence for Group Selection.

    Compared to the evidence for kin selection within gene-centered evolution (and that the evidence they have can be interpreted via gene-centered evolution and kin selection) seems to me to leave Wilson’s argument holding no water – but I’m no expert.

    Wilson’s comment is typical of many experts; attempting to argue from authority.  It is important to recognise, however, that while arguing from the consensus is subtly different it is, also, an argument from authority – and this is what Wilson is trying to say.

    What Wilson misses out, a little disingenuously perhaps, is that the subtle difference makes all the difference.  In science more voices means more people studying more evidence.

    Wilson thinks he is on to something and, lest we forget, all science is held to be provisional.  But, as Dawkins points out, there is a hole in the theory of Group Selection big enough to drive a double-decker bus through: What is it that Group Selection works on:

    Do groups have phenotypes, which might qualify them to count as gene vehicles? Convincing examples are vanishingly hard to find.

  23. but they won’t let you defer them to the consensus of smarter experts because they genuinely believe the phrase “argument from authority” referring to a fallacy means *all* arguments from authority are bad

    “Argument from authority” is an extremely misused term.  It’s almost always used as support for a libertarian view of the facts – that one person’s views are as good as another because attempting to quote anyone else in support is a fallacy. 

    That’s not the fallacy. The fallacy is using authority inappropriately.  An example is saying that you are justified in believing in climate change because you can quote the work of an individual scientist on the matter.  The appropriate authority is not one expert, but the consensus of experts. 

    I think the ‘Argument from Authority’ should be scrapped, as it is so widely misunderstood and abused.

  24. If you subscribe to a group selection view to explain biological diversity, then you believe there is some inherent property of a molecule that can assess the value of a resource.  Hopefully such is not the belief of rising students of evolution biology.

  25. ZenDruid.

    “Group selection is social Darwinism.” I think you could be right; at least it can be argued that it was used as an excuse for the distortion which was/is SD, but whether that abuse was politically motivated, or simply stemmed out of ignorance I don’t know; six of one and half a dozen of the other perhaps?

  26. Just because scientists have been treating “group selection” as a logical possibility, or to be more precise as an ontological possibility, does not mean that “group selection” is in fact a logical possibility.

  27. @OP:disqus
    blockquote – @OP – Richard  - Please note that Homo sapiens is a very peculiar species and probably not the best testbed for the theories under discussion.

      Indeed! – As was demonstrated on the earlier related discussion, it leads to many complications which cloud key issues.

  28. “Nature red in tooth and claw” more accurately describes what we really see, your warm and fuzzy group selection is not only inherently flawed, but, more importantly, it is not evident.

  29. I agree.  I reject group selection because it doesn’t actually make ontological sense. Group selection is little more than a semantic fudging of levels. I’m all for ‘top down’ type ontological arguments where there’s a case to be made for them…..but I just don’t see the point of group selection. As the OP says….there isn’t a single ‘outcome’ of group selection that cannot also be explained as an outcome of kin selection.

  30. Jumping into the lion’s den …

    Allow me to propose my version of group selection, which may be the common sense version Richard cautioned against.  If someone can truly convince me that it is illogical, I won’t say another word.  I’m not a biologist, so admittedly it’s audacious to open my trap here.  But I’m serious, and I ask that you read my proposal carefully and not dismiss it out of hand.

    Jerry’s definition of group selection – “selection among groups that differentially bud off subgroups, with those having good “group traits” becoming more numerous” – isn’t mine.  If it were, I’d agree that it can’t work.  Mine is something like, “Changes
    in frequency of certain alleles in the general population because of
    differential survival among groups, related to traits controlled by those alleles.”

    The qualities in question for humans are empathy and what it leads to – altruism, cooperation, group identification, and a moral sense.  The time when this occurred was when we were becoming fully human – probably in Africa around 100,000 years ago – when survival was difficult.  As hunter-gatherers, the groups would be large enough to repel predators and fight successfully against other groups, but not so large that the environment wouldn’t provide enough food.  Each group would consist of one or several families, plus friends, and others allowed to join.

    By chance, obviously, some of these groups would be more empathic and cooperative and altruistic than others.  To say it another way, the alleles which favored those qualities would be more numerous.  Obviously, cooperation in a group would help in providing food and shelter, fighting predators, and warring against other human groups - and would therefore aid survival of the group.  Groups with a greater percentage of selfish non-cooperators would be more likely to perish.

    Here’s how this version of group selection would alter the species.  No new genes would be created, but the percentage within the general population of those existing alleles which control empathy and the other qualities I mentioned would change.  In the groups which died out because of poor cooperation, the DNA of those individuals would be lost.  In the groups which survived – the better cooperators – those with a higher percentage of alleles favoring cooperation – their DNA would go forth.  The net result would be a shift in the Bell curve of the population as a whole of cooperative tendencies, because of a greater percentage in the population as a whole of those alleles favoring cooperation.

    Within any one group not everyone would be equally cooperative, of course.  The more cooperative groups overall would probably still contain selfish individuals, and those individuals might well score more food and women and thus have a somewhat better chance of surviving and reproducing than their more cooperative groupmates.  But the point is that overall, the percentage of cooperation-favoring alleles in the general population would increase.  We have plenty of sociopaths today, they didn’t disappear, but overall we’re fairly cooperative and concerned about each other.

    After the above instance of group selection, the group doesn’t bud off subgroups.  People move from group to group.  Rebellious teenagers leave one and join another, and so on.  The players are shuffled, new groups form, some by chance more cooperative than others, and the above process repeats itself, each iteration increasing cooperative tendencies within the species, for as long as the groups remain relatively isolated from each other, and competitive, and the increases in cooperation and altruism are helpful. 

    To me this seems obvious.  I look forward to learning where i’ve gone wrong.  I prefer reading logical objections to these concepts; please don’t simply tell me that they’ve been disproved by the experts, tell me how they were disproved.

  31. Since you seem to have considered all hypothesis about group selection, and you have either ruled them out or found them mistaken as kin selection, I would like to ask you if there is any formal mathematical model which analyzes the possibility that group selection has evolved not only through a process of multilevel NATURAL selection but also through a process of individual SEXUAL selection which could have fostered a set of gene-based “groupish” instincts such as altruism or a tendency towards male heroic acts under certain circumstances (specially when we are watched), punishment tendencies and so forth.

    I am talking about a kind of Fisher´s runaway process like the one that Geoffrey Miller uses to explain the uniqueness of human mind. Peacock tails can´t be explained only in terms of natural selection. Perhaps neither can group selection. What if the cost to survival that the individual takes when he behaves altruistically is out-balanced by a benefit for reproduction, as a consequence of becoming more atractive to females (and also more prestigious to males)?…
    For example, just think of certain human female tendencies: Why women get excited by men in certain uniforms? Why women fell in love with men that do heroic feats (apparently altruistic)? Why women prefer to get involved in a monogamous relationship with men who are empathetic and generous? and so forth…

    A little introspection make things even more clear. Would be we human males be equally motivated to do a heroic feat if we knew nobody is watching and nobody would ever know about it?…

    In my opinion sexual selection might be the key to explain instincts and “groupish” ( in Haidt´s terms) gene-based tendencies that seem to go againts the individual fitness. If these instincts and tendencies make individuals more atractive and prestigious, group benefits could easily align with individual benefits.

    Again, I ask you for for the papers or links where this hypothesis has been thoroughly discussed and formally presented.

  32. Interesting idea, Juan.  The classic explanation for men’s tendency to screw anything that moves is that his genetic seed is spread best by spreading widely and almost indiscriminately.  The classic explanation for women’s greater preference for monogamy is that they were programmed by evolution to select as a mate someone steady and reliable, so that they have help in raising children.  An empathic male would be a better long-term husband, although a heroic risk taker – soldier or fighter – wouldn’t.  One possible objection to your theory is that women today don’t seem to gravitate to men who are altruistic or group-oriented.  They’re more likely to go – at least short term – for rock stars or sports heroes or charismatic personalities – bad boys – than a quiet, empathic, unselfish good citizen.  Might have been different then, I suppose, when life was so much harsher and tenuous.  Certainly as you say war heroes in those days would have done very well with the ladies – but some war heroes act out of altruism, and some out of the opposite – a selfish desire for glory.  I do wonder how much power those early women had in choosing who to have sex with; a selfish individual would be more likely to take them by force.  I wouldn’t be surprised if sexual selection had played some role in evolution’s crafting of personality tendencies, but in which direction is unclear to me.

  33. @Juan. Exactly, Miller’s theory is enlightening as far as I can judge it, but I would really appreciate Richard’s thoughts on it. The only thing I have heard him say about it is a short description, but no deeper discussion.

Leave a Reply