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Kin Selection contradiction?

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General fitness, health and nutrition
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7 June 2004
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Brian Berns
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  1. Jim,

    in article [email hidden], Perplexed in
    Peoria at [email hidden] wrote on 6/23/04 9:06 AM:

    Quoted message said:

    "Guy Hoelzer" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    Jim,

    in article [email hidden], Perplexed
    in Peoria at [email hidden] wrote on 6/22/04
    1:16 PM:

    Quoted message said:

    "Guy Hoelzer" <[email hidden]> wrote in message
    "]news:[email hidden]...
    > in article [email hidden], Perplexed
    > in Peoria at [email hidden] wrote on 6/16/04
    > 10:15 PM: Whatever method is used, the result has to be
    > an "r" with the following property: Randomly choose one
    > of the two genes at any locus in the donor. Suppose
    > that the frequency of this allele in the general
    > population is "p". Now, randomly choose one of the two
    > genes at the same locus in the recipient. It must be
    > the case that the probability that the two randomly
    > selected genes are identical is (r + (1 - r)p). That
    > is, there is a probability r that they are identical
    > IBD, but if not, then there is still a probability p
    > that they are identical for other reasons - because the
    > allele is fairly common in the population.
    >
    > I think there is a big practical problem with applying
    > any models relying on IBD calculations, because our
    > data on genealogical history is virtually always very
    > shallow and incomplete.

    No doubt. I have no idea how field workers go about
    applying the model. Though I would imagine that the
    problems with estimating "b" and "c" are much larger
    than the problems of estimating "r".

    Well, "r" can never be known and can only be estimated
    with an underestimation bias. The degree of the bias
    depends on the amount of unknown inbreeding in the common
    ancestry of two individuals. At least "b" and "c" might
    be estimable without bias. Nevertheless, my biggest
    problem with the kin selection literature has to do with
    the uncritical (even unconscious) acceptance of kin
    selection as THE explanation for altruism-like behaviors
    observed in nature. I think the difficulty associated
    with estimating these parameters has a lot to do with
    giving in to this elegant model.

    I disagree about the effect of unknown inbreeding below.

    I fully agree that most altruism-like behaviors in nature
    (excluding parental care, and perhaps the social insects)
    are based on reciprocity rather than on the unilateral
    altruism covered by the Rule.

    It's good to know that our estimates of reality are close.

    Quoted message said:

    But this conversation began because, IMO, you made some
    false statements about the model - specifically that the
    applicability of rb>c depends upon the frequency of the
    altruistic allele. Or at least that is what you seemed to
    say. I am trying to defend the model against distortion,
    not to defend the importance or applicability of the
    model. You would have to have that discussion with someone
    who knows more "natural history". I am just an amateur OOL
    person who happened to get interested in Hamilton's Rule
    because it seemed to be controversial in this group. So,
    ultimately, I suppose this conversation can be blamed on
    Edser :-)

    Quoted message said:
    Quoted message said:

    > For example, all individual organisms (across all
    > species) are probably genealogically related, but...
    > There is also the problem of genealogical relatedness
    > in the face of mutation (common decent without
    > identity).

    If you believe that these issues are "big practical
    problems", then I suspect that you don't yet understand
    the model. The effect on r of

    Quoted message said:
    Quoted message said:
    Quoted message said:

    population.

    The problem is not just about pushing the estimate of "r"
    back additional generations. If that were the case, then
    I would agree that say 3 generations would be sufficient
    in most cases. Putting aside the fact that we rarely have
    information going back more than one generation, the
    greater issue has to do with inbreeding. The parameter
    "r" can take on any value in the face of inbreeding. For
    example, full sibs actually have 0.5 >= r <= 1. In fact,
    it is very common to have levels of inbreeding that make
    our naïve estimates of "r" significantly lower than they
    actually are. Truth be told, r=1 for every pair of
    individuals (even from different species) if you were to
    consider all the data (and ignore mutation/divergence).
    Do you have a justifiable rule for how ignorant we ought
    to be when we try to estimate "r" in order to make the
    false estimate useful in understanding kin selection in
    nature?

    It is clear that you still don't understand what "r" is.
    The history of the population, and the fact that it may be
    inbred in the recent or distant past is totally
    irrelevant. The only way inbreeding could be relevant
    would be if the population routinely breeds with close
    relatives for reasons other than small population.

    Forget IBD for a moment. Let p be the frequency of the
    altruistic allele in the general population. Let P be the
    frequency of the allele in the recipients. Define r to be
    that value which satisfies the equation P = r + (1-r)p
    That is, r represents, in a mathematically wierd way, the
    degree to which P exceeds p.

    As I said before, I like this way of thinking about the
    model, at least in some ways. I think you have internalized
    Maynard-Smith's version of Hamilton's model. Those two great
    thinkers thought about things in very different ways, IMHO.
    I am not sure that Hamilton ever verified that the Maynard-
    Smith version was consistent with his thinking. IMHO
    Hamilton thought of "r" primarily as a measure of
    genealogical relationship, which is not what it means in
    your equation above. My comment above about "0.5 >= r <= 1"
    was specifically referring to the genealogical "r".
    Nevertheless, I will go with the Maynard-Smith version of
    things for our dialogue.

    Quoted message said:

    This value r can be calculated (within sampling error) in
    the field if you take DNA samples from a random sample of
    the donor-recipient pairs. Of course, you have to
    normalize against the results for random pairs that are
    not donor-recipient. Or, if you have been observing the
    population for a few generations and you know genealogies
    of individuals, you can estimate r by truncated IBD. Or
    use truncated IBD if you are not a fieldworker and you
    just want to understand a reason why P>p might be
    expected.

    If you wish to understand why inbreeding is not important,
    perform the following thought experiment. Imagine a
    population derived from a single breeding pair which has
    grown to a population of 64 with the population doubling
    each generation. But, to make sure that we have variation
    for altruism, make both of the original pair heterozygous.
    Assume that mating is random and monogamous. "p" is 1/2.
    Assume the altruism is directed to full sibs. I think that
    you will find that r is not much larger than .5 and
    certainly less than .6. Or, for variety, start with p =
    3/4 or 1/4. "r" still will be less than .6 AFAICS

    You assumed something like random mating in an exponentially
    growing population, which basically the same as assuming
    that inbreeding is not occurring. It is certainly not
    surprising to conclude that inbreeding does not affect "r"
    when you assume that inbreeding does not occur. To
    illustrate why inbreeding IS important, consider a
    hypothetical population in which sib-sib mating is the norm.
    Such a population quickly loses its heterozygosity and
    becomes constituted by families filled with altruists and
    families lacking altruists. Now P>>p, and your "r" value is
    correspondingly much higher. So "r" is sensitive to
    inbreeding.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    And the chance that a mutation has destroyed an
    altruistic allele within those few generations is also
    small.

    In most cases that is probably true. Of course, we
    haven't even touched on the most common criticism of
    Hamilton's kin selection model, which is that altruistic
    behavior is probably not directly caused by a genetic
    mutation most of the time.

    I assume you mean that it is not caused by a single gene.
    (If you meant something different by "mutation", you will
    have to explain.)

    I use the term "mutation" in a more general sense here. For
    example, a chromosomal inversion might be involved, which
    does not disrupt the function of any particular gene. I am
    not trying to argue for the importance of non-genic
    mutations. I am merely allowing for effects of a broader
    class of mutations that would exhibit Mendelian segregation
    as assumed under Hamilton's model.

    Quoted message said:
    Quoted message said:

    It is probably far more complicated than that, and it is
    not clear to what extent the Hamilton's rule would work
    outside of the genetic framework. Here again is where my
    real problem lies. The vast majority of the empirical
    literature claiming to support Hamilton's model never
    addresses the issue of genetic control over altruism.

    Well, it turns out that non-additive epistasis is not a
    problem in this model, for the usual reasons. If you doubt
    this, just make the penetrance factor "f" below depend on
    both "p" and the frequency of some other gene(s). For a
    derivation of the rule, I think we are justified in
    treating each of these frequencies as a constant. Though
    perhaps we are now adding a weak selection assumption.
    However, pleiotropy turns out, surprisingly, to be more
    problematic. My toy derivation of the Rule, sketched
    below, doesn't handle it, for reasons sketched in my reply
    to Bill Morse. I don't know whether Hamilton [1964]
    handles it.

    I don't think Hamilton ever challenged his model with such
    mechanistic detail. I wasn't specifically implying anything
    about non-additive epistasis in my comment. In fact, I was
    thinking more about non-genetic effects altogether. Still,
    it is nice to know that the model appears robust to non-
    additive epistasis.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> Or, if like McGinn, you have an intuition that
    >> geneological history cannot be causal in this
    >> situation, ignore the IBD above. "r" is simply a
    >> measure of how much more likely than "p" it is that
    >> the two genes are identical for whatever reason. The
    >> key thing is that the formula (r + (1-r)p) gives the
    >> probability that the alleles are "shared".
    >>
    > Hmm. There are some things about this formulation that
    > I like, and some problems I see. Can you please save me
    > a little research time and tell us where you come by
    > the formula (r + (1-r)p)? Is this your interpretation
    > of Hamilton, or has it been published?

    It is a straightforward interpretation of the verbal
    explanation given in Maynard Smith's "Evolutionary
    Genetics" (2nd ed. p169)

    Now we can picture the genome of the recipient as
    consisting of two parts:
    1. a fraction r containing genes IBD to genes in the
    actor; and
    2. a fraction (1-r) consisting of genes that are a
    random sample of genes in the population.

    This is a very familiar modeling trick. The same thing is
    done when modeling inbreeding for other purposes. It is,
    however, just a trick that makes the math work out
    easily. The flaw becomes clear when you recognize that
    any random sample of the gene pool will potentially
    contain gene copies that are IBD with the target, so the
    fractions are not mutually exclusive. Given your
    definition of "r", "(1-r)" must be the fraction of the
    recipient's genome containing genes that are NOT IBD,
    which is different from "a random sample of genes in the
    population."

    I think that my argument above including the phrase
    "forget about IBD for a moment" addresses this concern.

    I agree that this second way in which you defined your
    parameters is more logical. However, that does not validate
    the way you defined them at first, which I still argue had a
    logical flaw. In fact, I think these two definition sets are
    inconsistent with one another, so you should decide which
    one you want to use and stick with it.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    As a "proof" that this is the correct interpretation,
    you can derive "rb>c" from this formula.
    1. Assume b and c are the benefits and costs of a single
    altruistic action.
    2. Assume a "penetrance factor" f (which may depend on
    r!) gives the number of times an allele causes
    altruism during its organism's lifetime. Assume that
    homozygous altruists share the cost between alleles.
    The factor f allows us to ignore whether the allele
    is dominant or recessive. For example, if the allele
    is recessive, then f will be small when p is small.
    But if the allele is dominant, then f will start
    large and then fall to half the original value, due
    to "sharing the credit" between homozygous gene
    instances.
    3. Calculate the total benefit received by recipients.
    Divide this up between carriers and non-carriers,
    with the benefit split in heterozygotes. Now
    calculate the "per capita" benefit to each haploid
    genome of the two types.
    4. Calculate the total and per capita costs of altruism.
    5. Compare the per capita benefit for non-carriers to
    the per capita (benefit - cost) for carriers. You
    will notice that the variable factor f cancels out,
    as does the allele frequency
    p. You are left with the fact that carriers receive
    enough extra altruism to compensate for the costs
    of acting altruistically when rb>c. Try it. As I
    wrote:

    This is very clever. Given my logical analysis above,
    your "proof" would seem to reveal cryptic ambiguities in
    Hamilton's original thesis. BTW, have you agreed in the
    past that all of this goes out the window for
    deterministic reasons when there is only one copy of the
    allele around, because then altruism only costs the
    allele fitness points?

    I understand what you are saying. Clearly, the only
    altruist in the population cannot also be a recipient,
    and hence can't be more fit than the rest of the
    population. (I could point out that you are assuming that
    the allele is dominant, but that is not my real objection
    to your point.)

    Frankly, I consider this a minor quibble - not much more
    forceful than if you had pointed out that a rabbit's speed
    is simply a drain on its metabolism if it never encounters
    a fox. But, I admit that what you say is true. I'm not
    going to try to convince you of the validity of my earlier
    response to your point.

    So I guess that you concede that the validity of Hamilton's
    rule depends "p", at least at this singular point. I suspect
    you would even concede that the effect of "p" would be
    observed at very low values of "p" when there is more than
    one copy of the altruism allele around. So, we only disagree
    about how far this effect will reach as you increase the
    value of "p", which I have been arguing depends strongly on
    population structure (and I would add population size).

    Quoted message said:
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    >> Why is that particular formula so important? Well,
    >> when you do the math, you will see that the average
    >> fitness of allele carriers will be greater than non-
    >> carriers, as long as the carriers direct their
    >> altruism to recipients of relatedness "r". That is,
    >> average fitness of carriers will be higher as long as
    >> rb>c. And the parameter "p" nicely cancels out of the
    >> equations. Hamilton's rule is independent of p. As
    >> long as "r" has the meaning above.
    >>
    > My criticism here is the same as one that I have been
    > posting earlier in this thread. Your conclusion is
    > sensitive to the implicit assumption that the
    > population is large (effectively infinite) and well
    > mixed. This combination does not generally exist in
    > nature, because the larger a system is the harder it is
    > to mix up.

    Not my conclusion. Hamilton's. But I think you exagerate
    the sensitivity.

    Like you, I would say "just try it." If you do a simple-
    minded model of agents interacting in space I think you
    will quickly see the sensitivity.

    Quoted message said:

    I think that all that is required is that the "well-
    mixed" or effectively random mating breeding population
    is larger than the local socially-interacting clique of
    each individual.

    Interesting. I would like to see the argument to this
    conclusion; or is this your "gut feeling" at this point.
    [BTW, I do not intent to impune "gut feelings." I admire
    people that are in touch with their guts.]

    Assume that the population is divided into "states",
    within which mating is random (well mixed). Assume that
    states are subdivided into "zip-codes", within which
    organisms interact. A state can have one zip-code, or
    several. Let "p" vary between states, but be constant
    within a state. Perform the derivation of the Rule
    separately for each state. Since p is constant within a
    state, the derivation still works in each case. Note that
    this would no longer be valid if a single zip-code covered
    two different states with different "p" values.

    I'm beginning to lose the thread of our argument, but I
    think the assumption of constant "p" values within
    subpopulations subverts the problem I was pointing to.
    Indeed, that assumption is inconsistent with Hamilton's
    model, which is about predicting changes in "p". If you
    loosen up your model a little to allow for dynamic "p"
    values, then each of your subpopulations can evolve
    deterministically in different directions under their own
    versions of Hamilton's rule. What would this mean for the
    evolution of the whole system? I don't think that Hamilton's
    rule would be a very precise guide at the global scale.

    Quoted message said:
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    And that "r" is pretty much the same everywhere.

    As I have indicated before, I think this is a very
    unrealistic assumption if you mean that "r" is the same
    everywhere for any particular individual. If you mean
    that the distribution of "r" is the same in the
    neighborhood of every individual, then this may be a
    reasonable approximation for some systems.

    The altruistic gene "directs the altruism" toward kin or
    neighbors. I am assuming that the gene produces the same
    biased effects everywhere, and, as you say, that
    neighborhoods are similar in their kinship structure
    everywhere.

    Quoted message said:
    Quoted message said:

    It is not important whether "p" is pretty much the same
    everywhere.

    What if I moved the pieces on the board of life so that
    each copy of the altruism allele is surrounded by a sea
    of purely selfish individuals? Note that this can only be
    done when "p" is small.

    But this means you have just set "r" to zero (or
    actually, to a small negative number)! Everywhere. So the
    Rule still works.

    Sorry. I forgot about your definition of "r". I was still
    using it in the genealogical sense of KIN selection.

    Quoted message said:
    Quoted message said:

    If "p" is large, then I could still change the balance of
    Hamilton's rule when "rb" is only slightly larger than
    "c" by isolating many copies of the altruism allele in
    local seas of selfishness.

    Your thought experiments strike me as artificial, and
    hence not particularly relevant. Maybe you are trying to
    tease out hidden assumptions. I think that the assumption
    that you are attacking here is an explicit one - that "r"
    is constant. In this case, you are still changing "r".

    So your "r" is critically dependent upon population
    structure. Right? Didn't you once argue that Hamilton's rule
    did not depend upon population structure?

    Quoted message said:
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    Quoted message said:

    > It also gets harder and harder to effectively mix the
    > finite population when "p" is either very small or very
    > large, because in either case there are very few quanta
    > of the rare allele.

    True enough, but now you are criticizing how
    deterministic Hamilton's rule is, rather than claiming
    that it is incorrect (biased) at extreme frequencies.

    Note my arguments above about bias when "p" is small
    and/or unevenly distributed.

    Noted. I am discounting your small p argument, and
    accepting your uneven distribution argument only if you
    have interactors that, for some reason, don't interbreed.
    Perhaps modern human India, Bosnia, or Northern Ireland
    fit your requirements. Hmmm. Now that I think about it,
    perhaps my zip-code analysis is extraneous.

    What do you think of my "flipside" argument above regarding
    systems constrained to sib-sib mating?

    Regards,

    Guy

  2. "Guy Hoelzer" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    in article [email hidden], Perplexed
    in Peoria at [email hidden] wrote on 6/23/04
    9:06 AM:

    Quoted message said:

    "Guy Hoelzer" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    in article [email hidden], Perplexed
    in Peoria at [email hidden] wrote on 6/22/04
    1:16 PM:
    > "Guy Hoelzer" <[email hidden]> wrote in message
    > "]news:[email hidden]...
    >> in article [email hidden],
    >> Perplexed in Peoria at [email hidden] wrote
    >> on 6/16/04 10:15 PM: Whatever method is used, the
    >> result has to be an "r" with the following property:


    Randomly

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> choose one of the two genes at any locus in the
    >> donor. Suppose that


    the

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> frequency of this allele in the general population is
    >> "p". Now,


    randomly

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> choose one of the two genes at the same locus in the
    >> recipient. It


    must be

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> the case that the probability that the two randomly
    >> selected genes


    are

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> identical is (r + (1 - r)p). That is, there is a
    >> probability r that


    they

    Quoted message said:
    Quoted message said:
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    >> are identical IBD, but if not, then there is still a
    >> probability p


    that

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> they are identical for other reasons - because the
    >> allele is fairly


    common

    Quoted message said:
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    Quoted message said:

    >> in the population. [snip]
    Well, "r" can never be known and can only be estimated
    with an underestimation bias. The degree of the bias
    depends on the amount of unknown inbreeding in the
    common ancestry of two individuals.


    [snip]

    Quoted message said:

    Putting aside the fact that we rarely have information
    going back more than one generation, the


    greater

    Quoted message said:
    Quoted message said:
    Quoted message said:

    issue has to do with inbreeding. The parameter "r" can
    take on any


    value in

    Quoted message said:
    Quoted message said:
    Quoted message said:

    the face of inbreeding. For example, full sibs actually
    have 0.5 >= r


    <= 1.

    Quoted message said:
    Quoted message said:
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    In fact, it is very common to have levels of inbreeding
    that make our


    naïve

    Quoted message said:
    Quoted message said:
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    estimates of "r" significantly lower than they actually
    are. Truth be


    told,

    Quoted message said:
    Quoted message said:
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    r=1 for every pair of individuals (even from different
    species) if you


    were

    Quoted message said:
    Quoted message said:
    Quoted message said:

    to consider all the data (and ignore
    mutation/divergence). Do you have


    a

    Quoted message said:
    Quoted message said:
    Quoted message said:

    justifiable rule for how ignorant we ought to be when
    we try to


    estimate "r"

    Quoted message said:
    Quoted message said:
    Quoted message said:

    in order to make the false estimate useful in
    understanding kin


    selection in

    Quoted message said:
    Quoted message said:
    Quoted message said:

    nature?

    It is clear that you still don't understand what "r" is.
    The history of


    the

    Quoted message said:
    Quoted message said:

    population, and the fact that it may be inbred in the
    recent or distant past is totally irrelevant. The only
    way inbreeding could be relevant


    would

    Quoted message said:
    Quoted message said:

    be if the population routinely breeds with close
    relatives for reasons


    other

    Quoted message said:
    Quoted message said:

    than small population.

    Forget IBD for a moment. Let p be the frequency of the
    altruistic


    allele

    Quoted message said:
    Quoted message said:

    in the general population. Let P be the frequency of the
    allele in the recipients. Define r to be that value
    which satisfies the equation P = r + (1-r)p That is, r
    represents, in a mathematically wierd way, the degree to


    which

    Quoted message said:
    Quoted message said:

    P exceeds p.

    As I said before, I like this way of thinking about the
    model, at least in some ways. I think you have
    internalized Maynard-Smith's version of Hamilton's model.
    Those two great thinkers thought about things in very
    different ways, IMHO. I am not sure that Hamilton ever
    verified that the Maynard-Smith version was consistent
    with his thinking. IMHO Hamilton thought of "r" primarily
    as a measure of genealogical relationship, which


    is

    Quoted message said:

    not what it means in your equation above.

    I'm not sure how Hamilton thought of "r". But someone else
    on this thread seemed pretty convinced that WDH thought it
    was a regression coefficient. If I understand things
    correctly, that is exactly what the "r" in my formula
    is.

    Quoted message said:
    Quoted message said:

    If you wish to understand why inbreeding is not
    important, perform the following thought experiment.
    Imagine a population derived from a single breeding pair
    which has grown to a population of 64 with the
    population doubling each generation. But, to make sure
    that we have variation for altruism, make both of the
    original pair heterozygous. Assume that mating is random
    and monogamous. "p" is 1/2. Assume the altruism is
    directed to full sibs. I think that you will find that r
    is not much larger than .5 and certainly less than .6.
    Or, for variety, start with p = 3/4 or 1/4. "r" still
    will be less than .6 AFAICS

    You assumed something like random mating in an
    exponentially growing population, which basically the same
    as assuming that inbreeding is not occurring.

    Inbreeding is not occurring now, though it did in the F1 and
    F2 generations.

    Yes, I am trying to show that in an inbred population, which
    is now mating randomly, the fact of the past inbreeding
    makes little difference in whether "r" calculated by IBD
    matches "r" calculated by my formula. I thought that I was
    responding to what you wrote above. Apparently, I
    misinterpreted what (still) seems to be a clear claim that
    the degree to which the population is inbred must be taken
    into account before assuming that a truncated IBD
    calculation is a good estimator of "r".

    Quoted message said:

    It is certainly not surprising to conclude that inbreeding
    does not affect "r" when you assume that inbreeding does
    not occur. To illustrate why inbreeding IS important,
    consider a hypothetical population in which sib-sib mating
    is the norm. Such a population quickly loses its
    heterozygosity and becomes constituted by families filled
    with altruists


    and

    Quoted message said:

    families lacking altruists. Now P>>p, and your "r"
    value is


    correspondingly

    Quoted message said:

    much higher. So "r" is sensitive to inbreeding.

    I never said it wasn't. To quote myself a few lines above:
    "The only way inbreeding could be relevant would be if the
    population routinely breeds with close relatives for reasons
    other than small population."

    I'm still not sure I understand the differences between
    Malecot's IBD and Wright's coefficient of relationship in
    populations with recent inbreeding. I also don't know
    which is the best estimator of "r". However, I am not yet
    convinced that one of these genealogical parameters, even
    if truncated after N generations, say, doesn't still give
    an estimate of "r" that is valid to within 1 / 2^N. You
    are welcome to try to convince me. Obviously, the true IBD
    "r" for full sibs will be greater than 1/2 in your
    incestuous population, as will the truncated IBD "r" and
    the real (my formula) "r". But I don't quite know how to
    calculate any of them.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >>> [snip] Or, if like McGinn, you have an intuition
    >>> that geneological history


    cannot

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >>> be causal in this situation, ignore the IBD above.
    >>> "r" is simply a measure of how much more likely than
    >>> "p" it is that the two genes


    are

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >>> identical for whatever reason. The key thing is that
    >>> the formula (r


    +

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >>> (1-r)p) gives the probability that the alleles are
    >>> "shared".
    >>>
    >> Hmm. There are some things about this formulation
    >> that I like, and


    some

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> problems I see. Can you please save me a little
    >> research time and


    tell us

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> where you come by the formula (r + (1-r)p)? Is this
    >> your


    interpretation of

    Quoted message said:
    Quoted message said:
    Quoted message said:

    >> Hamilton, or has it been published?
    >
    > It is a straightforward interpretation of the verbal
    > explanation given


    in

    Quoted message said:
    Quoted message said:
    Quoted message said:

    > Maynard Smith's "Evolutionary Genetics" (2nd ed. p169)
    >
    > Now we can picture the genome of the recipient as
    > consisting of two parts:
    > 1. a fraction r containing genes IBD to genes in the
    > actor; and
    > 2. a fraction (1-r) consisting of genes that are a
    > random sample of genes in the population.

    This is a very familiar modeling trick. The same thing
    is done when


    modeling

    Quoted message said:
    Quoted message said:
    Quoted message said:

    inbreeding for other purposes. It is, however, just a
    trick that makes


    the

    Quoted message said:
    Quoted message said:
    Quoted message said:

    math work out easily. The flaw becomes clear when you
    recognize that


    any

    Quoted message said:
    Quoted message said:
    Quoted message said:

    random sample of the gene pool will potentially contain
    gene copies


    that are

    Quoted message said:
    Quoted message said:
    Quoted message said:

    IBD with the target, so the fractions are not mutually
    exclusive. Given


    your

    Quoted message said:
    Quoted message said:
    Quoted message said:

    definition of "r", "(1-r)" must be the fraction of the
    recipient's


    genome

    Quoted message said:
    Quoted message said:
    Quoted message said:

    containing genes that are NOT IBD, which is different
    from "a random


    sample

    Quoted message said:
    Quoted message said:
    Quoted message said:

    of genes in the population."

    I think that my argument above including the phrase
    "forget about IBD for a moment" addresses this concern.

    I agree that this second way in which you defined your
    parameters is more logical. However, that does not
    validate the way you defined them at


    first,

    Quoted message said:

    which I still argue had a logical flaw. In fact, I think
    these two definition sets are inconsistent with one
    another, so you should decide which one you want to use
    and stick with it.

    I wish you had given that advise to Hamilton. ;-)

    Even in Maynard Smith's formulation, there is not the
    logical flaw that you claim. The fraction "r" does not
    contain ALL of the IBD genes. Only enough of them that the
    "1-r" fraction looks like the general population in ITS
    content of IBD genes.

    Another way of looking at this is that the fraction "r"
    contains approximately all of the genes that are recently
    IBD, and those genes that are IBD due to events in the
    distant past (a history you share with the general
    population) are in the (1-r) fraction. Of course, this fuzzy
    language cannot be part of the definition, it is part of a
    fuzzy "empirical" observation.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    [snip] BTW, have you agreed in the past that all of
    this goes out the window for


    deterministic

    Quoted message said:
    Quoted message said:
    Quoted message said:

    reasons when there is only one copy of the allele
    around, because then altruism only costs the allele
    fitness points?

    I understand what you are saying. Clearly, the only
    altruist in the population cannot also be a recipient,
    and hence can't be more fit than


    the

    Quoted message said:
    Quoted message said:

    rest of the population. [snip]

    Quoted message said:

    So I guess that you concede that the validity of
    Hamilton's rule depends "p", at least at this singular
    point. I suspect you would even concede


    that

    Quoted message said:

    the effect of "p" would be observed at very low values of
    "p" when there


    is

    Quoted message said:

    more than one copy of the altruism allele around. [snip]

    Actually, if "r" is calculated by my formula, I don't need
    to concede anything. My formula gives the value of "r" as
    zero (or actually -1/N) when there is only one carrier of
    the allele. So Hamilton's rule still works.

    What you are actually proving is that the assumption that
    r is independent of p is an impossible assumption to
    actually carry out when Dr Hoelzer is busy constructing
    counter-examples.

    Quoted message said:

    [snip] I think the assumption of constant "p" values
    within subpopulations subverts the problem I was pointing
    to. Indeed, that assumption is inconsistent with
    Hamilton's


    model,

    Quoted message said:

    which is about predicting changes in "p".

    My understanding of the jargon of pop gen is that an
    assumption that "p" is constant in a model which attempts to
    predict changes in "p" is known as a "weak selection
    assumption". It is, IIUIC, pretty standard.

    Quoted message said:

    [snip] So your "r" is critically dependent upon population
    structure. Right?

    Of course. It is very dependent on it if the altruism is
    dispersed indiscriminately to neighbors. It is less
    dependent if the altruism is based on kin recognition, but
    even here, it is hard to be nice to your kin if an ecologist
    hostile to Hamilton has rearranged the population so that
    you can't find your kin. :-)

    Quoted message said:

    Didn't you once argue that Hamilton's rule did not depend
    upon population structure?

    I don't recall doing so. I would be extremely reluctant to
    do so now, given your creativity in postulating structures.
    However, I will note that having "r" dependent on the
    population structure is a different matter than having the
    Rule dependent.

    Quoted message said:

    [snip] What do you think of my "flipside" argument above
    regarding systems constrained to sib-sib mating?

    You want to know what I *honestly* think of it? ;-)

    I can't offer an opinion until someone clears up the
    Wright/Malecot confusion for me. But I strongly suspect
    that it makes absolutely no difference to the
    applicability of the Rule when "r" is calculated using my
    formula. It may make a difference as to whether IBD is a
    good estimator of "r".

  3. "John Edser" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:


    JM:- I fully agree that most altruism-like behaviors in
    nature (excluding parental care, and perhaps the social
    insects) are based on reciprocity rather than on the
    unilateral altruism covered by the Rule.

    JE:- Proposition: Reciprocity is only stable if Darwinian
    fitness gains are mutualised.

    JM:- I have no problem agreeing with this statement. In
    fact, as I have said, I believe that even Hamilton's
    unilateral altruism without hope of reciprocation is favored
    by natural selection and by Hamilton's Rule, only if the
    Darwinian fitness gains are mutualized on average.

    I think that Hamilton realized this. I think that many,
    though perhaps not all, of the defenders of Hamilton in this
    newsgroup realize it.

    However, Hamilton's rule is not dispensible. It is the
    simple way to determine whether or not unilateral altruism
    directed toward kin does turn out to be effectively
    mutualized. It will be mutualized if and only if the
    recipients of your genetically directed altruism are enough
    like you genetically that they are genetically directed to
    be altruistic to you. If rb>c, then the fitness gains are
    mutualized. If rb<c, then an altruist is a net loser (as
    compared to non-altruists).

    JE:-

    Quoted message said:

    The most basic absolute assumption of evolutionary theory
    is Darwinian fitness which is a finite total.
    ______________________________________________________-
    ________
    Darwinian fitness is EXACTLY: The _total_ number of
    _fertile_ forms reproduced by _one_ parent within _one_
    population.
    ______________________________________________________-
    ________

    JM:- I am still unclear about what an "absolute assumption"
    is, but I would definitely agree that Darwinian fitness, as
    you have defined it, is central to evolutionary theory. As
    you will recall, Hamilton said so too, in 1964.

    JE:-

    Quoted message said:

    When an altruistic gene only relatively increases in freq
    at just one point in time because it increased more than
    the wildtype gene did, but the _total_ number of both
    genes _decreases_, then Hamilton et al cannot validly
    claim that the altruistic gene has spread because both
    genes are now heading for extinction.

    JM:- Here, you are arguing against the habit within
    population genetics of working with relative fitnesses
    rather than absolute fitnesses. But this habit is
    independent of Hamilton's kin selection theory - you can
    derive Hamilton's rule, AFAICS, regardless of whether "b"
    and "c" are taken to be increments to an absolute fitness or
    increments to a relative fitness. (Or, for that matter,
    increments to a selection coefficient).

    In any case, Hamilton's rule simply cannot favor spiteful
    behaviors that tend to drive the population to extinction
    unless r < 0. Hamilton did indeed consider this possibility
    in 1970, but it has not been encountered in the real world,
    AFAIK. Altruism could drive the population to extinction
    only if r>1, and that is impossible. Of course, selfishness
    can drive a population toward extinction under either
    Hamilton's rule or "Darwin's rule" - "0 > c". The reason is
    that NS is not Kantian - it never asks the question: "What
    if everyone did this?"

    JE:-

    Quoted message said:

    Likewise, if the total number of wildtype genes increases
    more than the total number of altruistic genes does
    because both totals have increased, then no altruism is
    evident even as the "altruistic gene" decreases relatively
    to the wildtype.

    JM:- I'm not sure I understand what you are saying here with
    "no altruism is evident".

    JE:-

    Quoted message said:

    Hamilton's relative measure of gene freq. change was never
    enough to substantiate his argument, which entirely
    dominates evolutionary theory even today, that a TESTABLE
    altruistic in fitness gene can spread.

    Without a fully testable definition of Darwinian
    fitness ...

    JM:- John, I'm not going to respond to this part about
    "testable". However, you will be happy to hear that
    Amazon has just today delivered to me a copy of "The
    Logic of Scientific Discovery", along with Miller's
    "Critical Rationalism". So, I may be re-engaging with you
    regarding epistemology in a few weeks when I have had
    time to read them.

    Quoted message said:

    JM:- [snip] I am just an amateur OOL person who happened
    to get interested in Hamilton's Rule because it seemed to
    be controversial in this group. So, ultimately, I suppose
    this conversation can be blamed on Edser :-)

    JE:- Don't shoot me I'm just a messenger who plays
    trombone for a living, shoot Hamilton et al who are paid
    to do this stuff...

    JM:- I hope to have my intellectual guns loaded in the near
    future. Only then will I begin the search for targets. ;-)

    Until then, have a nice day.

  4. William Morse said:
    Quoted message said:

    JM:- I fully agree that most altruism-like behaviors in
    nature (excluding parental care, and perhaps the social
    insects) are based on reciprocity rather than on the
    unilateral altruism covered by the Rule.

    Quoted message said:

    GH:- It's good to know that our estimates of reality
    are close.

    WM:- I disagree with both of your estimates of reality. I
    thought Hamilton originally suggested his rule to answer the
    question of how a feature like the toxicity of monarch
    butterflies could evolve. This feature has nothing to do
    with reciprocity. It might not be considered altruism by
    most, but in fact is, since being toxic doesn't help an
    individual at first - the individual will still be killed by
    the predator.

    JE:- If the sacrificed individual was just an infertile form
    then it only had zero Darwinian fitness so no Darwinian
    fitness altruism re: that individual, results from its
    death. The genes within infertile forms can only be selected
    within their _fertile_ parents, i.e. from whence they came
    because all genes within infertile forms cannot be passed
    on. Thus it is logically possible to argue that the parents
    of a predated species that had some of their infertile forms
    taken by predators, allowing the predator species to learn
    the prey type it was eating was toxic raised more and not
    less infertile forms to fertile adulthood. Note that if the
    toxicity to the predator species also reduced that predators
    Darwinian fitness then selection was reciprocal to prey and
    predator. Without predator toxicity, i.e. the prey species
    just tastes awful, this argument remains non reciprocal
    because it depends on selection acting unilaterally on prey
    within one population.

    The Darwinian selectee reciprocal argument between prey
    individuals, that excludes the predator, suggests that when
    fertile parents that contain the toxicity gene have a risk x
    of being taken but increase their Darwinian fitness by y
    amount because the risk is small enough such that y>x in its
    effect on the average Darwinian fitness of selectees, then
    the gene can spread. Note that most species are serial
    reproducers so that one Darwinian fitness total requires a
    finite time frame to complete. While incomplete, altruism
    can be _falsely_ diagnosed using Hamilton's rule because it
    did not provide a time frame within which to conclude
    altruism was the only possible explanation for +c. Measuring
    just a relative fitness difference over only one moment in
    time makes it impossible to conclude that any cost +c
    remained fitness altruistic for a serially reproducing
    species. At the end of the time frame +c may become -c in
    absolute terms.

    Note that the larger the population sharing the risk that a
    particular selectee (fertile form) will be eaten over the
    predator species learning curve, the smaller the risk each
    prey member has to take. This is due to risk reduction
    selected by organism fitness mutualism (OFM) between prey
    which uses the same logic as an insurance policy: the
    premium in risk < gain. Hamiltonian organism fitness
    altruism (OFA) is not required for either the reciprocal or
    non reciprocal argument, if and only if, Darwinian fitness
    remains _correctly_ identified which for Hamilton et al, has
    never been the case. It remains impossible to raise this
    issue within sbe because most Neo Darwinists that post here
    refuse to admit that they did not know what Darwinian
    fitness was.

    Because Darwinian fitness was not understood by Hamilton et
    al, no term for Darwinian fitness could be included within
    the rule so the rule cannot diagnose OFA as Hamilton
    suggested he could: all cases of +c. The rule cannot
    distinguish between -c (mutualism) and a reduced +c (reduced
    altruism). OFA can only be proven when Darwinian fitness is
    selected within nature to be lowered,
    i.e. the total number of fertile forms reproduced by one
    parent within one population is selected to be reduced.
    Because the rule only measures a relative difference at
    just a single point in time and not an absolute
    reduction/increase, the rule cannot distinguish between
    OFA and OFM which stand as total contradictions to each
    other. This means the rule remains unintelligible.

    Darwinian fitness is:-
    _________________________________________________
    The total number of _fertile_ forms reproduced by each
    parent within one population
    __________________________________________________

    Until a general term representing Darwinian fitness is
    appended to Hamilton's rule, the rule must remain
    biologically unintelligible.

    Quoted message said:

    snip<

    Regards,

    John Edser Independent Researcher

    PO Box 266 Church Pt NSW 2105

    [email hidden]

  5. Quoted message said:
    Quoted message said:
    Quoted message said:

    JM:- I fully agree that most altruism-like behaviors in
    nature (excluding parental care, and perhaps the social
    insects) are based on reciprocity rather than on the
    unilateral altruism covered by the Rule.

    Quoted message said:
    Quoted message said:

    JE:- Proposition: Reciprocity is only stable if Darwinian
    fitness gains are mutualised.

    Quoted message said:

    JM:- I have no problem agreeing with this statement. In
    fact, as I have said, I believe that even Hamilton's
    unilateral altruism without hope of reciprocation is
    favored by natural selection and by Hamilton's Rule, only
    if the Darwinian fitness gains are mutualized on average.

    JE:- Please note that everything of importance can remain
    hidden within an average,
    e.g. selective events acting at an _individualised_ level,
    unless you invoke group selection.

    Quoted message said:

    JM:- I think that Hamilton realized this. I think that
    many, though perhaps not all, of the defenders of Hamilton
    in this newsgroup realize it.

    JE:- The missing bit of Hamilton's model is the largest bit:
    any objective_ definition of Darwinian fitness to allow an
    UNAMBIGUOUS definition as to when organism fitness altruism
    (OFA) exists within the rule. This was highlighted within a
    previous exchange between Dr Bob O'Hara and myself: --------------quote----------------------

    1) 22/01/2004:

    JE:- What is the difference between a reduced positive c and
    a negative c? If c was an abolute measure of fitness then
    yes, a real difference exists. However c is only a relative
    fitness cost and not an absolute fitness cost, so what is
    the difference?

    BOH:-

    As far as the rule is concerned, none.

    ----------- end quote --------------------

    I have also requested Prof. J. Felsenstein a senior in this
    field who does post to sbe to answer some questions about
    this quote. So far he refused my request.

    In the quote above the rule is proven not to be able to
    distinguish between reduced altruism (any reduced positive
    c) and mutualism (any negative c) when organism fitness
    altruism (OFA) and organism fitness mutualism (OFM) stand in
    total contradiction to each other. This means the rule
    remains biologically _unintelligible_.

    Hamilton et al have no hope of claiming that (OFA) exists,
    even within just a vastly over simplified model of nature
    (let alone within nature itself) unless they know what
    Darwinian fitness was and can _measure_ a selectee's
    _reduction_ of it within the rule. This requires a general
    expression for Darwinian fitness to be explicitly
    represented within the rule. At the moment, no such
    expression exists.

    OFA has to prove that the actor has _reduced_ its Darwinian
    fitness because of the donation b to recipients related r
    (the number of recipients must be > 1 unless the recipient
    was a clone) and did not increase it, where Darwinian
    fitness can be proven to be:

    ____________________________________________________
    box 1 The total number of fertile forms reproduced into one
    population by one parent.
    ____________________________________________________

    The proof of the above definition that I provided is
    entirely experimental. When the Darwinian fitness of all
    Darwinian selectees (fertile forms) are held artificially
    equal within one natural population then all Darwinian
    natural selection must cease. You have to ask yourself why
    only a single Neo Darwinist who posts here (Dr Guy Hoelzer),
    has responded to:

    2) The definition of Darwinian fitness in box 1.
    3) Its experimental proof.
    4) The fact that Darwinian fitness and nothing else must be
    proven to reduced within Hamilton's rule in order to
    prove OFA.

    The fact that the same experiment proves that Dr Moran et al
    have not done their Darwinian (or epistemological) homework
    because they incorrectly suggest that Darwinian selection
    cannot be halted within one population as a control to
    varify that random sampling error or any other defined
    random process can cause "evolution". This fact alone,
    highlights a consistent misuse of mathematical models within
    Neo Darwinism let alone the deletion of Darwinian fitness
    within Hamilton's model!

    I have snipped your argument re: Hamilton's rule works no
    matter if absolute or relative fitness measures are
    employed. I will argue this view fundamentally flawed and
    hope to have in place a detailed reply quite soon

    Many Regards,

    John Edser Independent Researcher

    PO Box 266 Church Pt NSW 2105 Australia

    [email hidden]

  6. "Perplexed in Peoria" <[email hidden]> wrote in message news:<[email hidden]>...

    <snip>

    Quoted message said:

    I'm not sure how Hamilton thought of "r". But someone else
    on this thread seemed pretty convinced that WDH thought it
    was a regression coefficient. If I understand things
    correctly, that is exactly what the "r" in my formula
    is.

    That "someone else" is me. Hamilton agreed. And you are
    absolutely correct that your r (which is Hamilton's r) is a
    regression coefficient. This view of r is agreed upon by the
    majority of experts in the field of social evolution theory.

    <snip>

    Quoted message said:

    I'm still not sure I understand the differences between
    Malecot's IBD and Wright's coefficient of relationship in
    populations with recent inbreeding.

    The two concepts are not rigorously related to eachother in
    a general way. Wright was not entirely happy with Malecot's
    formalism because of this lack of rigour. But, if we adopt
    the standard approach whereby the components of Wright's r
    are expressed in terms of prob i.b.d., then even without
    inbreeding we get r equal to *twice* the prob i.b.d. between
    individuals, so they are not even nearly equivalent.

    <snip>

    Quoted message said:

    Actually, if "r" is calculated by my formula, I don't need
    to concede anything. My formula gives the value of "r" as
    zero (or actually -1/N) when there is only one carrier of
    the allele. So Hamilton's rule still works.

    You seem to be on the right track (i.e. your thinking does
    seem to be consistent with conventional thought on the
    mathematics of kin selection), however, if i understand what
    you are trying to do above, -1/N should be -1/(N-1).

    1/N + ((N-1)/N)*r = 0

    => r = -1/(N-1)

    I think the problem might be that you had not included the
    focal individual's allele frequency within the population
    allele frequency
    p. Although, as I said, I might have misunderstood what you
    were doing.

  7. William Morse <[email hidden]> wrote or quoted:

    Quoted message said:

    I thought Hamilton originally suggested his rule to answer
    the question of how a feature like the toxicity of monarch
    butterflies could evolve.

    This feature has nothing to do with reciprocity. It might
    not be considered altruism by most, but in fact is, since
    being toxic doesn't help an individual at first - the
    individual will still be killed by the predator.The
    predator is likely thereafter to avoid the species - so it
    is only after the toxicity gene has spread that it
    provides any advantage to the bearer. The initial benefit
    has to be to other individuals who are likely to share the
    gene - i.e. kin. Note here that the benefit does not have
    to be only to kin - in the monarch butterfly example the
    benefit would be to all monarch butterflies - the benefit
    to kin only has to exceed the cost to the individual.

    Conventionally (i.e. if you avoid species level selection),
    then spatialisation is important.

    I.e. it would really matter that a predator who had a toxic
    monarch for breakfast would be likely to be avoiding
    relatives for lunch and dinner - by virtue of the fact
    that they are in the same vicinity.

    Without spatialisation, benefit would accrue equally to all
    monarchs - and the costs would be paid only by those with
    the gene - a result which is bound to be a net loss for them
    in the competiton between them.

    If you permit species-level or group level explanations,
    toxic monarchs are no puzzle at all, of course.
    --
    __________
    |im |yler timtyler.orgtimtyler.org [email hidden] Remove
    lock to reply.

  8. Guy Hoelzer <[email hidden]> wrote in message news:<[email hidden]>...

    Quoted message said:

    in article [email hidden], William
    Morse at [email hidden] wrote on 6/26/04 10:00 PM:

    Quoted message said:

    It might not be considered altruism by most, but in fact
    is, since being toxic doesn't help an individual at
    first - the individual will still be killed by the
    predator.The predator is likely thereafter to avoid the
    species - so it is only after the toxicity gene has
    spread that it provides any advantage to the bearer. The
    initial benefit has to be to other individuals who are
    likely to share the gene - i.e. kin. Note here that the
    benefit does not have to be only to kin - in the monarch
    butterfly example the benefit would be to all monarch
    butterflies - the benefit to kin only has to exceed the
    cost to the individual.

    I agree that this accurately represents the kin
    selection model.

    I do not. If the gene benefitted all monarch butteflies
    equally, and carries any personal cost, then the gene is
    relatively unfit, and will decrease in frequency.

  9. "Name And Address Supplied" <[email hidden]> wrote in
    message "]news:[email hidden]...

    Quoted message said:

    "Perplexed in Peoria" <[email hidden]> wrote
    in message


    news:<[email hidden]>...

    Quoted message said:
    Quoted message said:

    Actually, if "r" is calculated by my formula, I don't
    need to concede anything. My formula gives the value of
    "r" as zero (or actually -1/N) when there is only one
    carrier of the allele. So Hamilton's rule still works.

    You seem to be on the right track (i.e. your thinking does
    seem to be consistent with conventional thought on the
    mathematics of kin selection), however, if i understand
    what you are trying to do above, -1/N should be -1/(N-1).

    1/N + ((N-1)/N)*r = 0

    => r = -1/(N-1)

    I think the problem might be that you had not included the
    focal individual's allele frequency within the population
    allele frequency
    p. Although, as I said, I might have misunderstood what
    you were doing.

    You have indeed understood what I was doing. I accept your
    correction. Silly mistake for me to have made, given the
    current thread on HW. And thanks for confirming that I am on
    the right track in my understanding of Hamilton. It is
    amazing how many philosophical and mathematical subtleties
    go into that simple result "rb>c".

  10. "Name And Address Supplied" <[email hidden]> wrote in
    message "]news:[email hidden]...

    Quoted message said:

    Guy Hoelzer <[email hidden]> wrote in message


    news:<[email hidden]>...

    Quoted message said:
    Quoted message said:

    in article [email hidden], William
    Morse at [email hidden] wrote on 6/26/04 10:00 PM:

    Quoted message said:

    It might not be considered altruism by most, but in
    fact is, since being toxic doesn't help an individual
    at first - the individual will still be killed by the
    predator.The predator is likely thereafter to avoid
    the species - so


    it is

    Quoted message said:
    Quoted message said:
    Quoted message said:

    only after the toxicity gene has spread that it
    provides any advantage


    to

    Quoted message said:
    Quoted message said:
    Quoted message said:

    the bearer. The initial benefit has to be to other
    individuals who are likely to share the gene - i.e.
    kin. Note here that the benefit does


    not

    Quoted message said:
    Quoted message said:
    Quoted message said:

    have to be only to kin - in the monarch butterfly
    example the benefit


    would

    Quoted message said:
    Quoted message said:
    Quoted message said:

    be to all monarch butterflies - the benefit to kin
    only has to exceed


    the

    Quoted message said:
    Quoted message said:
    Quoted message said:

    cost to the individual.

    I agree that this accurately represents the kin
    selection model.

    I do not. If the gene benefitted all monarch butteflies
    equally, and carries any personal cost, then the gene is
    relatively unfit, and will decrease in frequency.

    I agree with NAS's quibble, though, as Tyler points out, the
    butterfly "altruism" can be shoehorned into Hamilton if
    there is spatial structure and the gene benefits local
    monarchs more than it benefits all monarchs. Local monarchs
    are disproportionately likely to be kin.

    However, the sheer weakness of the resulting bias toward kin
    is the reason why I don't believe that Hamilton has solved
    this puzzle.

  11. in article [email hidden], Name And Address Supplied at
    [email hidden] wrote on 6/30/04 8:35 AM:

    Quoted message said:

    Guy Hoelzer <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:

    in article [email hidden], William
    Morse at [email hidden] wrote on 6/26/04 10:00 PM:

    Quoted message said:

    It might not be considered altruism by most, but in fact
    is, since being toxic doesn't help an individual at
    first - the individual will still be killed by the
    predator.The predator is likely thereafter to avoid the
    species - so it is only after the toxicity gene has
    spread that it provides any advantage to the bearer. The
    initial benefit has to be to other individuals who are
    likely to share the gene - i.e. kin. Note here that the
    benefit does not have to be only to kin - in the monarch
    butterfly example the benefit would be to all monarch
    butterflies - the benefit to kin only has to exceed the
    cost to the individual.

    I agree that this accurately represents the kin
    selection model.

    I do not. If the gene benefitted all monarch butteflies
    equally, and carries any personal cost, then the gene is
    relatively unfit, and will decrease in frequency.

    I should have stated an assumption I always make that I am
    convinced is always true. That is that every population is
    embedded in space and exhibits isolation by distance. So,
    close relatives are generally closer in space than randomly
    selected members of a species, and the prey-avoidance
    lesson learned by the predator who tasted the toxic
    butterfly is more likely to live in the same neighborhood
    as the dead butterfly's close relatives than a randomly
    chosen butterfly individual. In a viscous population the
    kin selection model can work even when altruists practice
    random acts of kindness.

    Cheers,

    Guy

  12. [email hidden] (Name And Address Supplied) wrote
    in :"]news:[email hidden]:

    Quoted message said:

    Guy Hoelzer <[email hidden]> wrote in message
    news:<[email hidden]>...

    Quoted message said:

    in article [email hidden], William
    Morse at [email hidden] wrote on 6/26/04 10:00 PM:

    Quoted message said:

    It might not be considered altruism by most, but in
    fact is, since being toxic doesn't help an individual
    at first - the individual will still be killed by the
    predator.The predator is likely thereafter to avoid the
    species - so it is only after the toxicity gene has
    spread that it provides any advantage to the bearer.
    The initial benefit has to be to other individuals who
    are likely to share the gene - i.e. kin. Note here that
    the benefit does not have to be only to kin - in the
    monarch butterfly example the benefit would be to all
    monarch butterflies - the benefit to kin only has to
    exceed the cost to the individual.

    Quoted message said:
    Quoted message said:

    I agree that this accurately represents the kin
    selection model.

    Quoted message said:

    I do not. If the gene benefitted all monarch butteflies
    equally, and carries any personal cost, then the gene is
    relatively unfit, and will decrease in frequency.

    Note that I did _not_ state that the gene would benefit all
    monarch butterflies equally - only that the benefit does not
    have to be _only_ to kin. Now it may well be the case that
    once the gene becomes widespread in a population it will be
    fixed by drift, but that is not the point. Up until
    fixation,in most real populations the gene will still
    benefit kin more than non-kin simply because of the
    proximity effect. Presumably your argument against equal
    benefit is based on the idea that otherwise those who do not
    have the gene will gain the benefit without incurring the
    cost. Regarding this point,it is interesting to note that in
    the real world there are mimicking species, but I am unaware
    of significant polymorphism in toxicity occurring for
    populations ( this may simply not have been studied).
    Perhaps one of the factors that accounts for this is that an
    individual who is freeloading will tend to prosper in
    relation to nearby individuals, so that there will then be a
    local population which does not have the gene. But if a
    predator "learns" that monarch butterflies are no longer
    toxic, it will tend to demolish precisely the local
    population (since the predator will feed in one locale).This
    will tend to hasten the fixation of the toxicity gene.

    Yours,

    Bill Morse

  13. Guy Hoelzer <[email hidden]> wrote in
    :"]news:[email hidden]:

    Quoted message said:

    in article [email hidden], Perplexed
    in Peoria at [email hidden] wrote on 6/23/04
    9:06 AM:

    Quoted message said:

    I fully agree that most altruism-like behaviors in nature
    (excluding parental care, and perhaps the social insects)
    are based on reciprocity rather than on the unilateral
    altruism covered by the Rule.

    Quoted message said:

    It's good to know that our estimates of reality are close.

    I disagree with both of your estimates of reality. I thought
    Hamilton originally suggested his rule to answer the
    question of how a feature like the toxicity of monarch
    butterflies could evolve.

    This feature has nothing to do with reciprocity. It might
    not be considered altruism by most, but in fact is, since
    being toxic doesn't help an individual at first - the
    individual will still be killed by the predator.The predator
    is likely thereafter to avoid the species - so it is only
    after the toxicity gene has spread that it provides any
    advantage to the bearer. The initial benefit has to be to
    other individuals who are likely to share the gene - i.e.
    kin. Note here that the benefit does not have to be only to
    kin - in the monarch butterfly example the benefit would be
    to all monarch butterflies - the benefit to kin only has to
    exceed the cost to the individual.

    Yours,

    Bill Morse

  14. "William Morse" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    Guy Hoelzer <[email hidden]> wrote in
    :"]news:[email hidden]:

    Quoted message said:

    in article [email hidden], Perplexed
    in Peoria at [email hidden] wrote on 6/23/04
    9:06 AM:

    Quoted message said:

    I fully agree that most altruism-like behaviors in
    nature (excluding parental care, and perhaps the social
    insects) are based on reciprocity rather than on the
    unilateral altruism covered by the Rule.

    Quoted message said:

    It's good to know that our estimates of reality are
    close.

    I disagree with both of your estimates of reality. I
    thought Hamilton originally suggested his rule to answer
    the question of how a feature like the toxicity of monarch
    butterflies could evolve.

    This feature has nothing to do with reciprocity. It
    might not be


    considered

    Quoted message said:

    altruism by most, but in fact is, since being toxic
    doesn't help an individual at first - the individual will
    still be killed by the predator.The predator is likely
    thereafter to avoid the species - so it is only after the
    toxicity gene has spread that it provides any advantage to
    the bearer. The initial benefit has to be to other
    individuals who are likely to share the gene - i.e. kin.
    Note here that the benefit does not have to be only to kin
    - in the monarch butterfly example the benefit


    would

    Quoted message said:

    be to all monarch butterflies - the benefit to kin only
    has to exceed the cost to the individual.

    I think you are correct that Hamilton's model was intended
    to cover this. However, I don't think it succeeds.

    There is certainly an odd kind of intraspecific unilateral
    altruism involved here. But the situation is complicated by
    being interwoven with an even odder kind of interspecific
    reciprocity. The butterfly informs the bird that it is
    distasteful by its markings. The bird "reciprocates" by not
    eating the butterfly. Within the butterfly species, it is
    altruistic to be honest with the bird - this maintains the
    bird-butterfly bond of trust which is beneficial to all
    butterflies.

    I have an unpublished model not involving kin selection to
    explain this situation. The reciprocity with the bird is
    essential for my mechanism to work.

  15. Bill,

    in article [email hidden], William Morse
    at [email hidden] wrote on 6/26/04 10:00 PM:

    Quoted message said:

    Guy Hoelzer <[email hidden]> wrote in
    :"]news:[email hidden]:

    Quoted message said:

    in article [email hidden], Perplexed
    in Peoria at [email hidden] wrote on 6/23/04
    9:06 AM:

    Quoted message said:

    I fully agree that most altruism-like behaviors in
    nature (excluding parental care, and perhaps the social
    insects) are based on reciprocity rather than on the
    unilateral altruism covered by the Rule.

    Quoted message said:

    It's good to know that our estimates of reality are
    close.

    I disagree with both of your estimates of reality.

    ;-(

    Quoted message said:

    I thought Hamilton originally suggested his rule to answer
    the question of how a feature like the toxicity of monarch
    butterflies could evolve.

    I think his mind was certainly open enough to include this
    sort of phenomenon. I personally see his primary motivation
    as one to come up with a plausible model for the evolution
    of individual altruism given the crumbling of Wynne-Edwards
    style group selection that was happening at the time. The
    discrediting (right or wrong) of "for the good of the
    species" thinking re-introduced altruistic phenomena as a
    big problem begging a Darwin-istic explanation. Hamilton met
    this daunting challenge by subtly shifting the target of
    selection below (and some argue above) the level of the
    individual, although his implicit use of alternative levels
    of selection was rather cryptic in his own writings.
    However, the success of the theory of kin selection paved
    the way for David Sloan Wilson and others to develop
    multilevel selection theory as a more general expression of
    Hamilton's ideas.

    Quoted message said:

    This feature has nothing to do with reciprocity.

    I don't want to quibble, but I am not so sure about this
    claim. After all, if we are both toxic to predators, then I
    benefit by being near you and you benefit by being near me.
    I think that reciprocity is fundamentally about positive
    feedback whether or not social interaction is involved.

    Quoted message said:

    It might not be considered altruism by most, but in fact
    is, since being toxic doesn't help an individual at first
    - the individual will still be killed by the predator.The
    predator is likely thereafter to avoid the species - so it
    is only after the toxicity gene has spread that it
    provides any advantage to the bearer. The initial benefit
    has to be to other individuals who are likely to share the
    gene - i.e. kin. Note here that the benefit does not have
    to be only to kin - in the monarch butterfly example the
    benefit would be to all monarch butterflies - the benefit
    to kin only has to exceed the cost to the individual.

    I agree that this accurately represents the kin
    selection model.

    Cheers,

    Guy

  16. "Guy Hoelzer" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    in article [email hidden], William
    Morse at [email hidden] wrote on 6/26/04 10:00 PM:

    Quoted message said:

    I thought Hamilton originally suggested his rule to
    answer the question of how a feature like the toxicity
    of monarch butterflies could evolve.

    [snip GH opinions regarding history which are debatable,
    but not worth debating]

    Quoted message said:
    Quoted message said:

    This feature has nothing to do with reciprocity.

    I don't want to quibble, but I am not so sure about this
    claim. After all, if we are both toxic to predators, then
    I benefit by being near you and you benefit by being near
    me. I think that reciprocity is fundamentally about
    positive feedback whether or not social interaction is
    involved.

    I agree that "reciprocity is fundamentally about positive
    feedback", but I strongly disagree that "I benefit by being
    near you and you benefit by being near me" constitutes
    feedback. For feedback, you require something like "I
    benefit *because* you benefit". Or, to look at it in another
    way, the distinguishing feature of a feedback *loop* is that
    it can be broken. If I cease to provide benefit to you, then
    thru some chain of causality, this must result in you
    ceasing to provide benefit to me.

    You don't have feedback just because you have causal
    "arrows" pointed in both directions. Those arrows have to be
    connected.

  17. In Guy Hoelzer said:

    phenomenon. I personally see his primary motivation as one
    to come up with a plausible model for the evolution of
    individual altruism given the crumbling of Wynne-Edwards
    style group selection that was happening at the time. The
    discrediting (right or wrong) of "for the good of the
    species" thinking re-introduced altruistic phenomena as a
    big problem begging a Darwin-istic explanation. Hamilton
    met this daunting challenge by subtly shifting the target
    of selection below (and some argue above) the level of the
    individual, although his implicit use of alternative levels
    of selection was rather cryptic in his own writings.

    I saw an interesting paper showing how kin selection can
    be modeled mathematically with Price's Theorem in terms
    of group selection. I also recall a paper by Maynard-
    Smith showing how to model kin selection in terms of
    individual selection. But I can't remember the titles --
    can anybody help?

    As to level at which selection is _really_ occuring, I liked
    Sean Rice's essay, pantheon.yale.edugroup.html

    I noticed an article by H. Allen Orr in the New York Review
    of Books, in which he implies that kin selection requires
    selection at the level of the gene. I was surprised that he
    would make that statement. Sober addressed this belief on
    pages 335 to 355 of his book, "The Nature of Selection."
    Hamilton wrote that the classical models "admit no
    possibility of the evolution of any characters which are on
    average to the disadvantage of the individuals possessing
    them," and Dawkins wrote that Hamilton got biologists to
    stop focusing on organisms and start focusing on genes, but
    both these statements are misleading. Population genetics
    models had always paid attention to individual genes, and
    they show how characters that are to the disadvantage of
    individuals can evolve. Sober argues that inclusive fitness
    is not a substitute for Darwinian fitness; instead, it is a
    rule of thumb that approximates fitness. The fitness of a
    trait is commonly defined as the average fitness of the
    organisms possessing them. Sober writes, "Hamilton's insight
    was that there are many ways for a gene to be advantageous
    on average...Classical models of selection show how a
    phenotype can be selected against without being
    eliminated...On the other hand, this and other standard
    models of selection do imply that a gene that is on average
    deleterious must be eliminated, if selection is the only
    force at work. Kin selection does not alter this fundamental
    fact. Indeed, the greater average fitness of a gene is an
    absolute criterion for increase under selection, regardless
    of the level at which selection occurs." Hamilton simply
    showed how the mean fitness of a gene or a trait can be
    caused by interesting interactions among kin. Presenting
    inclusive fitness as a new definition of fitness or as
    evidence that all selection is genic selection obscures the
    basic point.

    Paul

  18. in article [email hidden], Perplexed in Peoria at
    [email hidden] wrote on 6/30/04 8:35 AM:

    Quoted message said:

    "Guy Hoelzer" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    in article [email hidden], William
    Morse at [email hidden] wrote on 6/26/04 10:00 PM:

    Quoted message said:

    I thought Hamilton originally suggested his rule to
    answer the question of how a feature like the toxicity
    of monarch butterflies could evolve.

    [snip GH opinions regarding history which are debatable,
    but not worth debating]

    Quoted message said:
    Quoted message said:

    This feature has nothing to do with reciprocity.

    I don't want to quibble, but I am not so sure about this
    claim. After all, if we are both toxic to predators, then
    I benefit by being near you and you benefit by being near
    me. I think that reciprocity is fundamentally about
    positive feedback whether or not social interaction is
    involved.

    I agree that "reciprocity is fundamentally about positive
    feedback", but I strongly disagree that "I benefit by
    being near you and you benefit by being near me"
    constitutes feedback. For feedback, you require something
    like "I benefit *because* you benefit". Or, to look at it
    in another way, the distinguishing feature of a feedback
    *loop* is that it can be broken. If I cease to provide
    benefit to you, then thru some chain of causality, this
    must result in you ceasing to provide benefit to me.

    You don't have feedback just because you have causal
    "arrows" pointed in both directions. Those arrows have to
    be connected.

    Good point. So it may be more accurate to describe this
    model, let's call it the "proximity=mutual benefit" model,
    as something more like quantum entanglement than positive
    feedback. I agree that this models lacks what we might call
    reciprocity, but don't you think that the symmetry of
    positive effect alone is sufficient to drive the reciprocal
    altruism model?

    I was actually going to say something about symmetry, rather
    than "positive feedback" originally, but I wasn't sure that
    I could express myself well enough in that framework to find
    a resonance with this audience.

    Regards,

    Guy

  19. "Paul Gallagher" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:

    In <[email hidden]> Guy Hoelzer
    <[email hidden]> writes:

    Quoted message said:

    I saw an interesting paper showing how kin selection can
    be modeled mathematically with Price's Theorem in terms of
    group selection. ... But I can't remember the titles --
    can anybody help?

    There have been many. If you're the kind of person who wants
    original sources, you want Selfish and Spiteful Behavior in
    an Evolutionary Model
    W. D. Hamilton, Nature 228, 1218-20 (1970) But also see
    what Hamilton says about this paper in retrospect in
    Chapters 5, 6, and 8 of Narrow Roads. And follow the
    paper's reference to Price's paper in Nature.

    My favorite paper on the topic is a big one: "A geometric
    view of relatedness", Alan Grafen, 1985
    users.ox.ac.ukoseb.pdf

    Also good is: "The Price Equation, Fisher's fundamental
    theorem, kin selection, and causal analysis", Steve Frank,
    1997 stevefrank.org97Evol Causal
    R.html

    Quoted message said:

    I also recall a paper by Maynard-Smith showing how to
    model kin selection in terms of individual selection.

    I also would be interested in seeing a reference for
    that paper.

    Quoted message said:

    As to level at which selection is _really_ occuring, I
    liked Sean Rice's essay,
    pantheon.yale.edugroup.html

    I liked it less well. See my reply to Edser on the thread
    "Hamilton's Rule: light at the end of a LONG tunnel?" Also,
    notice what Frank and Grafen say about the dynamic
    insufficiency of Price's equation. This means that a group
    selection interpretation of kin selection needs to make some
    auxiliary assumptions about the breeding structure, so as to
    restore the variance within groups that gets discharged by
    selection. It is difficult to do so in a way that also
    maintains the variance between groups.

  20. "Guy Hoelzer" <[email hidden]> wrote in message "]news:[email hidden]...

    Quoted message said:

    in article [email hidden], Perplexed
    in Peoria at [email hidden] wrote on 6/30/04
    8:35 AM:

    Quoted message said:

    "Guy Hoelzer" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    After all, if we are both toxic to predators, then I
    benefit by being near you and you benefit by being near
    me. I think that reciprocity is fundamentally about
    positive feedback whether or not social interaction is
    involved.

    I agree that "reciprocity is fundamentally about
    positive feedback", but I strongly disagree that "I
    benefit by being near you and you benefit by being near
    me" constitutes feedback. For feedback, you require
    something like "I benefit *because* you benefit". Or, to
    look at it in another way, the distinguishing feature of
    a feedback *loop* is that it can be broken. If I cease
    to provide benefit to you, then thru some chain of
    causality, this must result in you ceasing to provide
    benefit to me.

    You don't have feedback just because you have causal
    "arrows" pointed in both directions. Those arrows have
    to be connected.

    Good point. So it may be more accurate to describe this
    model, let's call it the "proximity=mutual benefit" model,
    as something more like quantum entanglement than positive
    feedback.

    A very evocative analogy! I share what it evoked in me
    below. But first...

    Quoted message said:

    I agree that this models lacks what we might call
    reciprocity, but don't you think that the symmetry of
    positive effect alone is sufficient to drive the
    reciprocal altruism model?

    Symmetry of positive effect, along with some other
    conditions, may well be enough to lead to the increase in
    altruism in an evolutionary model. It does so in Hamilton's
    model. My main concern here was to defend the received
    meaning of "reciprocal". In both common usage and in
    Trivers' model, the word assumes a causal linkage in the
    feedback. It also assumes that the feedback is directed to
    an individual. A reciprocator is not "repaying a debt to
    society". He is repaying a "debt" to an individual. In
    Hamilton's kin selection model, by contrast, there is
    symmetry of positive effect, but not "reciprocity".

    "Reciprocity" need not involve intentionality, however. I
    think that the interchange of materials between cytoplasm
    and mitochondria is reciprocal, in that the various antiport
    machinery constrains the cytoplasm to stoichiometrically
    supply food to the organelle to the extent that it extracts
    energy. That is perfectly good reciprocity, by my
    definition. In operation, it is not even teleonomic - merely
    teleomatic, if that.

    Quoted message said:

    I was actually going to say something about symmetry,
    rather than "positive feedback" originally, but I wasn't
    sure that I could express myself well enough in that
    framework to find a resonance with this audience.

    One of the first things they teach you in an applied
    statistics text is that "correlation" is not the same thing
    as "causation". And one of the canonical examples of how you
    can have a correlation without direct causation is when the
    two things that are correlated are both results of the same
    fundamental cause.

    However, in spite of this warning, we continue the practice
    in mathematical science of reasoning by writing down
    equations in which the two sides are joined by the symmetric
    equal sign. One cannot tell by inspection which side of the
    equation is causal of the other. And, in fact, in our
    mathematical reasoning, the direction of the causality is
    not important. Models can still work, and can be
    explanatory, even though they may involve what looks like
    causal nonsense.

    A prime example of this is Hamilton's kin selection. It is
    essential to that model that there be genetic correlation
    between the donor and the recipient. In the case of
    siblings, or cousins, neither the donor nor the recipient is
    the cause of the genetics of the other. However, there is a
    correlation between them, caused by a shared fundamental
    cause - namely the genetics of a shared ancestor. It was
    Hamilton's genius to recognize that correlation is enough,
    that you don't need causality, or rather that the math still
    works if some of the causal arrows must be traced backward.
    Edser doesn't seem to accept this. Similarly, in physics
    Bohr recognized that correlation is enough, that you don't
    need conventional causality. But Einstein, along with
    Podolsky and Rosen, couldn't seem to accept this. (I don't
    know whether the stroking implicit in this analogy will
    soften or harden John's position. Time will tell ;-)

    All of this tends to weaken my claim that "causality",
    rather than "symmetry" is important in the meaning of
    "feedback" or of "reciprocity". I guess that it is not
    absolutely essential that an explanatory model have all of
    the causal arrows connected and pointing in the same
    direction. But still, I would like to reserve the words
    "feedback" and "reciprocity" for those (most common) cases
    in which the arrows DO all connect properly.

    One final observation, or perhaps speculation: The reason
    why science so rarely needs to consider explanations in
    which causal arrows run in the wrong direction is that such
    explanations usually don't work. Something else, not yet
    considered here, is needed before backward causality - the
    future determining the past - can actually be effective. It
    is evocative, for me at least, that physicists sometimes
    refer to this "something else" as a "selection rule".
    Wilkins is perhaps wise in trying to rein in my use of
    teleological language before I say something really
    dangerous. ;-)

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