This site is not maintained. Click here for the new website of Richard Dawkins.

← A misguided attack on kin selection

A misguided attack on kin selection - Comments

hfaber's Avatar Comment 1 by hfaber

rB > C. It seems so simple but Hamilton must have been a genious. I still wonder: what are the correct dimensions for B and C? Energy? Or the number of offspring?

Mon, 30 Aug 2010 19:32:50 UTC | #508148

God fearing Atheist's Avatar Comment 2 by God fearing Atheist

Why are Coyne and Dawkins pontificating in the blogsphere with the hoi polloi? Argumentum ad populum?

Write a letter/paper and send it to Nature.

EDIT: Its to help us hold the breach in the walls from the hoard of IDiots that are about to exploit the opportunity, until such time as they can publish a paper in Nature.

Updated: Mon, 30 Aug 2010 20:02:58 UTC | #508166

Jos Gibbons's Avatar Comment 3 by Jos Gibbons

hfaber - fitness.

Mon, 30 Aug 2010 20:26:34 UTC | #508193

Neodarwinian's Avatar Comment 4 by Neodarwinian

I, for one, think Wilson did not overreach with Sociobiology, but kin selection is too well established among too many taxa to dismiss so cavalierly with one paper in even a journal as prestigious as Nature. Will have to study this more deeply to see what Wilson and company are about.

Mon, 30 Aug 2010 22:29:22 UTC | #508254

vanghelie's Avatar Comment 5 by vanghelie

Hi,

I find this intriguing:

"Alex Kacelnik points out to me that kin selection is the only way in which worker adaptations such as soldier jaws and honeypot abdomens – phenotypes that are never expressed in reproductive individuals – could have evolved. 'Colony selection' and 'superorganisms' don't do the trick. You have to talk about shared genes in individuals, with conditional phenotypic expression."

Can someone who understands this expand a bit and explain (to a layman) how kin selection explains the evolution of these traits?

The way I see it, something like "individuals who share this gene cooperate more" does not make sense as the individuals themselves do not reproduce; the only relevant consequence of their cooperation (or lack there of) is how well they can "help" the queen reproduce.

Mon, 30 Aug 2010 22:51:15 UTC | #508268

Rattlesnake's Avatar Comment 6 by Rattlesnake

Richard, I tried very hard to follow your fascinating piece, but must ask this: how do you define 'devaluation'? As in the following: " C is exceeded by the Benefit to the recipient, B, devalued by the coefficient of Relatedness, r."

Thanks

Mon, 30 Aug 2010 23:00:15 UTC | #508273

Electric_Monk's Avatar Comment 7 by Electric_Monk

Comment 6 by Rattlesnake :

Richard, I tried very hard to follow your fascinating piece, but must ask this: how do you define 'devaluation'? As in the following:

" C is exceeded by the Benefit to the recipient, B, devalued by the coefficient of Relatedness, r."

Thanks

r is the relatedness of the recipient to the actor (what proportion of genes they share) - a sister, parent or offsping (for a diploid species) would have an r of 1/2, a cousin would have an r of 1/8, an identical twin or a clone would have an r of 1 and so on. (r can never be greater than 1 since you can't be more related to someone else than you are to yourself - thus "devalued")

Therefore, if the recipient in an individual case were the sister of the actor then the benefit would have to be double the cost to the actor. In the case of cousins the benefit would have to be eight times the cost to the actor and so on.

Sister: 1/2B > C Cousin: 1/8B > C

Updated: Tue, 31 Aug 2010 05:39:27 UTC | #508364

Electric_Monk's Avatar Comment 8 by Electric_Monk

Comment 5 by vanghelie :

Can someone who understands this expand a bit and explain (to a layman) how kin selection explains the evolution of these traits?

The way I see it, something like "individuals who share this gene cooperate more" does not make sense as the individuals themselves do not reproduce; the only relevant consequence of their cooperation (or lack there of) is how well they can "help" the queen reproduce.

For a good explanation of this see The Selfish Gene, however, the (i might be a little wrong about details) short answer is that, in haplodiploid species (like ants) females share more genes with their sisters than with their own offspring. This means that it is in the "interest" of the "selfish" genes to increase the number of siblings of an individual at the expense of offspring since this is the most efficeint way to propogate the maximum number of copies of themselves into the next generation.

see the comments in the linked article for a fuller explanation

Updated: Tue, 31 Aug 2010 05:59:15 UTC | #508365

MatthaiNazrani's Avatar Comment 9 by MatthaiNazrani

From the perspective of this layman, E O Wilson's group selection has always sounded like pure wishful thinking in the Lysenkoist tradition, so this fails to surprise me.

Tue, 31 Aug 2010 07:17:04 UTC | #508383

s.k.graham's Avatar Comment 10 by s.k.graham

@ Comment 5 by vanghelie:

Can someone who understands this expand a bit and explain (to a layman) how kin selection explains the evolution of these traits?

vanghelie,

Ordinarily our genes get into the next generation by the fact that we reproduce. But if you are related to someone, then you will share some fraction (probabilisticly) of genes. So any gene, A, that you have has a r chance (or think 100 time r percent chance) of being in an individual with relatedness r (for examply normal diploid parents such as humans have relatedness 1/2 with their own offspring, siblings also have relatedness 1/2 -- in other words having more siblings is just as good as having offspring for reproducing your genes. If gene A in some way makes you sacrifice time/energy/resources so that you have less chance of producing offspring yourself, but you increase the chance of someone (or several someones) related to you having offspring, then the "loss" to gene A in not being pass on in your own offspring may be offset by the gain in its chances of being passed on in the offspring of your relatives. Hamiltons formula, rB>C captures this mathematically. For natural selection to favor a gene that causes you to make sacrifices for your kin, the cost to you, C my be less than the benefit to your kin times their relatedness (actually you might benefit muliple kin, so it should be sum(rB)>C where you are summing over all the kin who benefit from your sacrifice and r & B may be different for each individual kin).

The genes for soldiers jaws and honeypots can only have been passed on through queens that were related to the soldiers and honeypots. The were favored by natural selection because these traits in the workers helped the queen reproduce. The queen never has the soldier jaws or honeypot abdomen, so those traits did not directly help her reproduce, those traits only help her because they help her workers to help her. Her workers are her kin. Hence kin selection (reproductive success of the queen, who is kin to her workers) is the natural selection mechanism that favored the soldiers jaw and honeypots ant's abdomen.

Does that clear it up?

Tue, 31 Aug 2010 08:24:29 UTC | #508396

s.k.graham's Avatar Comment 11 by s.k.graham

please forgive all the typos above. hopefully they do not make it too unreadable.

Tue, 31 Aug 2010 08:27:38 UTC | #508399

Richard Dawkins's Avatar Comment 12 by Richard Dawkins

Thank you s.k.graham for your explanation. My own exposition, as Electric Monk says, is in The Selfish Gene, and I apologise for assuming, in my Notes above, prior knowledge of that book or equivalent.

To expand on the point about haplodiploidy being incidental to Hamilton's classic double paper of 1964, out of 49 pages ( in the Narrow Roads of Gene Land reprint), the haplodiploidy hypothesis occupied a mere three and a half pages. This was followed by another three pages discussing the fact that Hymenopteran queens often have multiple mates -- precisely the point advanced by Nowak et al as a 'new' criticism! Hamilton then went on to discuss the case of the termites (which are not haplodiploid) thereby anticipating another of the 'new' criticisms. The termites, as Hamilton also pointed out, have a completely different tell-tale predisposition to eusociality under his theory, namely recurrent inbreeding, which raises the coefficient of relatedness in a way parallel to the 'haplodiploidy effect'.

Given that Nowak et al seem to think haplodiploidy is central to Hamilton's theory, I am astounded that they totally fail to mention the work of Robert Trivers and Hope Hare on sex ratio biases in Hymenoptera (see The Selfish Gene for a full discussion). Trivers and Hare calculated optimal sex ratios from the point of view of a queen, and from the point of view of a worker ant, given haplodiploidy. If the queen exerts power over the ratio of males to females, the stable ratio of colony investment in males versus reproductive females would be 1:1. If the workers have control over the sex ratio, there would be three times as much investment in females as in males. They went on to measure the actual ratios in 20 species of ants and found a female bias as per the haplodiploidy prediction. There was even an 'exception that proves the rule' in the form of slave-making species whose workers have no power because the work is all done by slaves. The Trivers/Hare study has been criticised on various grounds, but it is astonishing that Nowak et al ignore it completely.

In any case, the most important point is that Hamilton's theory does not -- and never did -- stand or fall by the enigmatic special case of haplodiploidy. On the contrary, by far the bulk of work using the theory has been done on ordinary diploid organisms, and the bulk of Hamilton's own thinking on the subject concerned diploid organisms. Hamilton's theory of Inclusive Fitness is not something set apart from 'Standard Natural Selection Theory'. It is Standard Natural Selection theory, made complete by filling in a logical implication that had previously been overlooked.

Richard

Tue, 31 Aug 2010 09:42:50 UTC | #508420

Dr. Strangegod's Avatar Comment 13 by Dr. Strangegod

I think I just got a lot smarter. Thanks to all!

Tue, 31 Aug 2010 13:47:46 UTC | #508544

vanghelie's Avatar Comment 14 by vanghelie

s.k.graham,

Thank you for your reply.

I'm sorry to say I am still very confused.

In the first paragraph you explain Hamilton's rule.

Most of the second paragraph is clear:

The genes for soldiers jaws and honeypots can only have been passed on through queens that were related to the soldiers and honeypots. The were favored by natural selection because these traits in the workers helped the queen reproduce. The queen never has the soldier jaws or honeypot abdomen, so those traits did not directly help her reproduce, those traits only help her because they help her workers to help her. Her workers are her kin.

Of course the genes could only have mattered if the soldiers are related to her.

Hence kin selection (reproductive success of the queen, who is kin to her workers) is the natural selection mechanism that favored the soldiers jaw and honeypots ant's abdomen.

This final conclusion is what really doesn't help me at all. Read superficially, it seems obviously true. But after having explained Hamilton's rule as part of 'defining' kin selection, are you suggesting that this rule is relevant here? If yes, why? (that is what I was and am asking)

Here is my specific problem:

If gene A in some way makes you sacrifice time/energy/resources so that you have less chance of producing offspring yourself, but you increase the chance of someone (or several someones) related to you having offspring, then the "loss" to gene A in not being pass on in your own offspring may be offset by the gain in its chances of being passed on in the offspring of your relatives.

How can something like this be relevant here? Who is sacrificing something so that IT has less chance of producing offspring? The gene results in some workers sacrificing something for other workers and (directly or indirectly) the welfare of the queen - but they have 0 (or very little) chance of producing offspring anyway. As far as the queen is concerned (which is the only reproducing agent here), the gene only results in an increase of effectiveness of how she is "cared for" (regardless if some workers suffer for others because of it..)

Tue, 31 Aug 2010 13:50:07 UTC | #508545

s.k.graham's Avatar Comment 15 by s.k.graham

@ Comment 14 by vanghelie:

Who is sacrificing something so that IT has less chance of producing offspring? The gene results in some workers sacrificing something for other workers and (directly or indirectly) the welfare of the queen - but they have 0 (or very little) chance of producing offspring anyway. As far as the queen is concerned (which is the only reproducing agent here), the gene only results in an increase of effectiveness of how she is "cared for" (regardless if some workers suffer for others because of it..)

OK. I think I see your question. If the ants had already evolved the sterile worker-caste system (which requires hamilton's equation because the workers are sacrifice reproductive health) then subsequent details of evolution of features of the worker caste do not represent further sacrifice, as you point out. But that just means "C" in the cost side of rB>C is zero for those new traits like soldier jaws. B is the benefit to the queen's reproductive success, and r is the relatedness of the worker to the queen. So both the cocept of kin-selection and Hamilton equation are relevant, but C=0 (or almost zero) may make Hamilton's equation seem trivial... but remember that B must both remain positive.

Bear in mind that mutations can come along any time that make workers more likely to reproduce (a "negative cost" to the worker) but the same mutation may also have "negative benefit" for the queen, and Hamilton's equation will apply in that case as well ("is rB more negative than C?").

rB>C is a kind of minimum requirement for the gene responsible to be selected. It is interesting to turn it around so that B' is benefit to the individual (B'=C) and C' is cost to kin (C'=-B), then we have B'>rC'-- a trait that benefits me personally must not cause an excessive net cost to my kin!

When it comes to competing traits (genes for large vs. small jaws, or whatever) if the genes are mutually exclusive then (r * B_1) >?< (r * B_2) is the thing that matters for the already-sterile workers. More generally, what matters among competing traits is whether (r * B_1) - C_1 >?< (r * B_2) - C_2. (There does nto seem to be a way to do subscripts... sot the _1 etc, are subscripts)

Tue, 31 Aug 2010 17:06:46 UTC | #508700

vanghelie's Avatar Comment 16 by vanghelie

If the ants had already evolved the sterile worker-caste system

Isn't this where we started from? We are talking about "phenotypes that are never expressed in reproductive individuals" so sterile workers must already be in the picture..

Ok so with C=0, the equation basically says "a trait can develop if it has a positive influence on the queen". Duh, that's a triviality.

Note that you can make an equation like "rB > C" always hold in any case by just making up values for B or C; I don't see the insight that gives you in cases like this where it resolves to a triviality like "B > 0".

More specifically, I don't understand how this relates to:

'Colony selection' and 'superorganisms' don't do the trick. You have to talk about shared genes in individuals, with conditional phenotypic expression.

I don't see what insight brought by Hamilton's rule "does the trick". It seems we are simply saying what 'colony selection'/'superorganism' says as well - the positive benefit to the queen is what matters.

Updated: Tue, 31 Aug 2010 17:50:33 UTC | #508741

Anaximander's Avatar Comment 17 by Anaximander

(r can never be greater than 1 since you can't be more related to someone else than you are to yourself - thus "devalued")

Why not? What if somebody has two copies of my "altruism gene"?

Tue, 31 Aug 2010 18:07:57 UTC | #508760

s.k.graham's Avatar Comment 18 by s.k.graham

Ok so with C=0, the equation basically says "a trait can develop if it has a positive influence on the queen". Duh, that's a triviality.

Note that you can make an equation like "rB > C" always hold in any case by just making up values for B or C; I don't see the insight that gives you in cases like this where it resolves to a triviality like "B > 0".

C is only (approximately) zero for some genes and not others. The equation applies to any and all genes. Also you don't get to "make up values" for B and C... the values are what they are -- you may or may not be able to easily measure them, but you don't just get to "make them up". Some genes will have rB>C and other genes will not. The latter genes will die out. The former may or may not flourish depending on whether which among competing genes has the largest rB-C.

rB>C is no more "trivial" when C is zero than when C is any other number. Who cares if it is a simple trivial equation? If it describes a (minimum) requirement for natural selection to favor a gene -- the so be it. Actually my expression rB-C is really the more important thing, or more precisely sum(rB)-C -- this is basically the "inclusive fitness" of a give gene (really we should be saying allele, here, to get technical), and it is this notion of inclusive fitness that is the real insight. Between two alleles competing for the same spot on the genome, the one with higher sum(rB)-C will be favored (but if they are close, chance plays a role, or neither becomes dominant in the population).

The genes responsible for sterile worker castes were selected because they had higher sum(rB)-C than competing genes within the population. In the context of already sterile worker caste, genes which have negligible effect on reproduction of the worker have approximately C=0 in Hamilton's equation, but that does not mean the equation does not apply, that just means C=0 for those genes.

Finally if the workers did not (high high probability due to kinship) share their genes with the queen, then it would not matter which traits they had because those traits would not be passed down to future generation of workers. This is why we say 'colony selection' or 'group selection' is not enough. It is the success of the genes that matter. Sterility of the workers is not an absolute. If some mutation (or novel combination of genes) causes a worker to have a small chance of reproducing under certain circumstances (negative C), without having an overly negative impact on the queen's reproduction (negative B), then rB-C will be a net gain for the genes in the worker and since there is a chance the queen has the same mutation, there is a good chance that that gene will flourish.

So it is the inclusive fitness sum(rB)-C of a gene (allele) that always matters, and it is sufficient explanation for 'altruistic' and 'cooperative' behaviors. Simply enhancing 'group fitness' is neither necessary nor sufficient for a gene to thrive. The same is true of 'individual fitness'. There is an overlap between group fitness and sum(rB), but group fitness can contain irrelevancies (because groups do not necessarily comprise kin), and sum(rB) includes things that group fitness does not (because kin do not all necessarily form cohesive groups). Individual fitness (individual reproductive success) is reflected in C, but in terms of a reduction of individual fitness

Tue, 31 Aug 2010 19:02:45 UTC | #508786

s.k.graham's Avatar Comment 19 by s.k.graham

@ Comment 17 by Anaximander:

(r can never be greater than 1 since you can't be more related to

someone else than you are to yourself - thus "devalued")

Why not? What if somebody has two copies of my "altruism gene"?

Anaximander,

Relatedness is not measured one allele at a time. We do not say "for allele A I have a relatedness to you of 1 because I have one copy and you have one copy, but for allele B our r-value is 0, because I have it and you don't."

Relatedness is based on the probability (without having sequenced our genomes) that any given allele in my genome is also in yours. The r-value is determined by knowing the chain(s) of reproductive relationships that connect two organisms, and the mechanism(s) of inheritance (diploid, haploid, clone...). You get half of your genes, at random, from each of your parents. So does your sibling. If you crunch the math that means that each of your alleles also has a 50% chance of being in your sibling. If you & I had all of our great grandparents in common (but none of our grandparents or parents) then our relatedness would be 1/8 (unless I made an arithmetic error). This definition of r-value is based on "new mutations" and on locations in the genome where there is wide variety of competing alleles in the population. This is where "the action is" in evolution. Obviously if a at a particular location on the genome, a particular allele has come to dominate the population (say 99% of individuals have it), then the probability of it being shared between any two individuals is going to be about 99% regardless of kinship connections -- we don't care about those alleles in calculating relatedness. We do care about the rare alleles that make up the other 1%. If you have one of those alleles, then your relatedness to another person tells you the chance that one of your relatives also has it.

There is a fuzzy area for alleles which have come to be present in a large fraction of the population. Basically the larger the fraction of population that already has a specific allele, the less accurate the relatedness calculation is in predicting probability that others have that allele (it will give a lower probability lower than actual -- like the 99% case mentioned above). The evolutionary biologists (the mathematically inclined ones anyway) know about these complications (or should) and take them into account (or should).

Tue, 31 Aug 2010 19:49:18 UTC | #508809

Jos Gibbons's Avatar Comment 20 by Jos Gibbons

The relatedness of A to B is defined as the limit, as an allele's frequency in the population tends to 0, of the probability that allele is in A, given it is in B. Since probabilities are at most 1, so are the limits of series of them, where said limits are well-defined (which it can be shown is applicable here). I suppose if we replace "The relatedness of A to B is defined as the limit, as an allele's frequency in the population tends to 0, of the probability that allele is in A, given it is in B. Since probabilities are at most 1, so are the limits of series of them, where said limits are well-defined (which it can be shown is applicable here). I suppose if we replace "probability that allele is in A" with "mean number of copies of that allele is in A" and subdivided the condition into "it is in B at least once", "it is in B exactly once" and "it is in B twice", you may be on to something, but I reckon the limit part of the definition would still spoil it.

Tue, 31 Aug 2010 20:25:18 UTC | #508819

s.k.graham's Avatar Comment 21 by s.k.graham

Jos, thanks for the precise mathematical definition. I hadn't seen that before, but if I was going to formulate a definition, "in the limit as frequency goes to zero" captures precisely what I was saying -- that it is in terms of the "rarer" alleles -- those with low frequency. Relatedness gives exact probabilities for a brand spanking new mutation. It is a very good approximation for low frequency alleles.

Tue, 31 Aug 2010 21:51:48 UTC | #508855

Richard Dawkins's Avatar Comment 22 by Richard Dawkins

I don't see what insight brought by Hamilton's rule "does the trick". It seems we are simply saying what 'colony selection'/'superorganism' says as well - the positive benefit to the queen is what matters.

Yes, well the reason you don't see it is that you are trying to rediscover the wheel, and to do so by asking questions of a few individuals whom you happen to meet on an Internet thread, instead of going back to the books and reading the background. Forgive me for suggesting it, but The Selfish Gene might not be a bad place to start. You could then advance to Alan Grafen's brilliant chapter in Krebs and Davies, Behavioural Ecology. You might then be ready to tackle Hamilton himself, Volume 1 of Narrow Roads of Gene Land. I'm sorry, but this is difficult stuff, brilliant stuff, and you can't expect to understand its elegance and theoretical power after only a few desultory exchanges on a chat thread.

Richard

Tue, 31 Aug 2010 22:58:50 UTC | #508878

Epich's Avatar Comment 23 by Epich

It's unfortunate that this confusion still exists, since the explanation given in the Selfish Gene is quite accessible and should clear up the matter neatly for just about anyone. Do we know whether Nowak or Wilson have read the book?

(Speaking of the Selfish Gene, I remember asking a question about the chapter on children blackmailing parents in the forums, but I don't know how to access old posts to remind myself of the question and its answers.)

Wed, 01 Sep 2010 00:27:27 UTC | #508897

LetsHaveAnAdventure's Avatar Comment 24 by LetsHaveAnAdventure

YES! Sometimes I wish religion would hasten its departure to make room for more fun discussions like this.

Richard's comment above is important and worth listening to. This stuff is brilliant, and finding oneself confused about an article like this is a perfect opportunity to run off and read about some of the most interesting ideas of the past century. However, it`s not always easy to know where to look for the best references.

After 34 years, The Selfish Gene is still a wonderful place to start. The book gives fantastic introductions to Hamilton's concept of inclusive fitness (relevant to this discussion), as well as to Robert Trivers's theories of parental investment and parent offspring conflict that play a major role in research that attempts to explain animal behavior (humans included).

Indeed, the preface to The Selfish Gene was written by Robert Trivers, and was (as Steven Pinker has noted) probably one of the most important prefaces in the history of publishing (Trivers outlines his massively influential theory of self-deception in one sentence, almost as if he was making casual bar conversation).

Other great sources are the foundational papers themselves, which are fairly easy reads once one understands the basics. Hamilton's two-part paper on kin selection can be found here The Genetical Evolution of Social Behavior 1 (change "64a" to "64b" in the url for part 2). Robert Trivers's famous paper on reciprocal altruism is here The Evolution of Reciprocal Altruism

If you're more interested in understanding the Neo-Darwinian Synthesis via its application to those bizarre bipedal apes, you`re looking for books on Evolutionary Psychology. Some of the better textbooks are: Evolutionary Psychology: The New Science of the Mind by David Buss and Evolutionary Psychology: An Introduction by Lance Workman and Will Reader. As for more rigorous resources, a classic compilation of essays and papers is The Adapted Mind and another destined to become a classic (in which Richard wrote the afterword) is The Handbook of Evolutionary Psychology, which is my current preferred distraction from my less interesting math research.

If you`re looking for popular accounts, look for any book by Steven Pinker, in particular How the Mind Works or The Blank Slate.

Finally, whether applied to humans or non-human animals, the cousin-subjects of sociobiology, behavioral ecology, evolutionary psychology, and human ethology are very frequently the subject of criticism so hostile that the unacquainted reader might have difficulty deciding whether they`re legitimate fields of study at all. Most of the works cited above address these claims in detail, but a good compilation of responses to such criticisms can be found here: The Critical Eye.

Anyways, sorry for the mountain of babbling. As a mathematical physics student, I rarely get an opportunity to talk about this other obsession of mine.

Wed, 01 Sep 2010 00:45:54 UTC | #508905

InYourFaceNewYorker's Avatar Comment 25 by InYourFaceNewYorker

Indeed. I loved both The Selfish Gene andThe Extended Phenotype (the latter was fucking brilliant) but both books (again, especially the latter) took me forever to get through because I wanted to understand the concepts as much as possible and some of the nitty gritty was hard to wrap my head around! My poor brain cells! Hmm... that would be interesting. A picture of someone's brain while the person is engaged in reading The Extended Phenotype. Yes, the human brain is an organ of elegant complexity... ^_^

Julie

Comment 22 by Richard Dawkins : I'm sorry, but this is difficult stuff, brilliant stuff, and you can't expect to understand its elegance and theoretical power after only a few desultory exchanges on a chat thread.

Richard

Updated: Wed, 01 Sep 2010 01:55:00 UTC | #508923

ShellmanSherman's Avatar Comment 26 by ShellmanSherman

Nowak et al is yet again a small minded attack on the ONLY theory that can explain the spread of a "gene". My problem with this camp of thinkers is their inability to provide a clear testable alternative hypothesis. This latest is like all the rest of the DS Wilson camp's science fair: a focus' on what they don't want to see continue --Hamilton's inclusive fitness theory. Their brand of selection can't even handle a meiosis event.

I see a pattern emerging: Start with a complex vehicle, and mash genes in there, at the mercy of the vehicle. No elegant view of a gene here or its probability of spread. We just see a favored "group". And the target will move, depending on the flavor of criticism, because after all, their brand of selection is "multi-level". Only, they forgot to bring a theory and relate it to the favored spread of a gene.

Wed, 01 Sep 2010 11:47:34 UTC | #509126

Anaximander's Avatar Comment 27 by Anaximander

A picture of someone's brain while the person is engaged in reading The Extended Phenotype.

Is the camera (taking that picture) an example of an extended phenotype? If it is, it should be explained in the book - on the page the person is reading, when the picture is taken.

Wed, 01 Sep 2010 14:31:00 UTC | #509218

LetsHaveAnAdventure's Avatar Comment 28 by LetsHaveAnAdventure

@ Comments 25 and 27: There's plenty of cool fMRI work on reading. A fun source is Ch. 12 of Ward's The Student's Guide to Cognitive Neuroscience 2nd Ed. called "The Literate Brain".

Wed, 01 Sep 2010 15:24:58 UTC | #509252

Anaximander's Avatar Comment 29 by Anaximander

RD: Yes, well the reason you don't see it is that you are trying to rediscover the wheel...

Why did evolution not invent the wheel? (Why are there no animals moving like a wheel?)

Thu, 02 Sep 2010 07:24:55 UTC | #509574

InYourFaceNewYorker's Avatar Comment 30 by InYourFaceNewYorker

Comment 29 by Anaximander :

RD: Yes, well the reason you don't see it is that you are trying to rediscover the wheel...

Why did evolution not invent the wheel? (Why are there no animals moving like a wheel?)

Well, in Philip Pullman's The Amber Spyglass there are diamond-shaped animals that use giant tree seeds as wheels. :)

Thu, 02 Sep 2010 10:50:54 UTC | #509677