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The Primate Diaries


Notes on science, politics, and history from a primate in the human zoo.
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The Good Fight

The views expressed are those of the author and are not necessarily those of Scientific American.


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Prominent scientists are in a bitter struggle over the origins of kindness. But the root of this conflict may be the most ironic part of all.

"Debate" by Nathaniel Gold

"Scientific Debate" by Nathaniel Gold

What would it take for you to give your life to save another? The answer of course is two siblings or eight cousins, that is, if you’re thinking like a geneticist. This famous quip, attributed to the British biologist J.B.S. Haldane, is based on the premise that you share on average 50% of your genes with a brother or sister and 12.5% with a cousin. For altruism to be worth the cost it should ensure that you break even, genetically speaking.

This basic idea was later formalized by the evolutionary theorist William Hamilton as “inclusive fitness theory” that extended Darwin’s definition of fitness–the total number of offspring produced–to also include the offspring of close relatives. Hamilton’s model has been highly influential, particularly for Oxford evolutionary biologist Richard Dawkins who spent considerable time discussing its implications in his 1976 book The Selfish Gene. But in the last few years an academic turf war has developed pitting the supporters of inclusive fitness theory (better known as kin selection) against a handful of upstarts advocating what is known as group selection, the idea that evolutionary pressures act not only on individual organisms but also at the level of the social group.

The latest row was sparked by the publication of Edward O. Wilson’s new book, The Social Conquest of Earth, which followed up on his 2010 paper in the journal Nature written with theoretical biologists Martin Nowak and Corina Tarniţă. In both cases Wilson opposes kin selection theory in favor of the group selection model. For a revered scientist like Wilson–a Harvard biologist, recipient of the Crafoord Prize (the Nobel of the biosciences) and two-time Pulitzer prizewinner–to adopt a marginal and widely disputed concept has received a lot of attention and caused other prominent scientists to step forward and defend the mainstream point of view.

For example, writing at The Prospect magazine, in what The Guardian newspaper called “a searingly critical review,” Dawkins argued that the proposal in Wilson’s book was based on “erroneous and downright perverse misunderstandings of evolutionary theory.” Joining him at the website Edge was Harvard psychologist Steven Pinker who wrote that group selection was a “false allure” and “a loose metaphor, more like the struggle among kinds of tires or telephones.” Likewise, University of Chicago biologist Jerry Coyne dismissed group selection on his blog as “a fuzzy and nebulous concept” and one that merely “has an innate appeal to those with a penchant for the religious and the spiritual.” It should go without saying that online commenters were considerably less kind (a notable exception being at Edge, where scholars were invited to comment independently).

Taken together, along with the 137 scientists who signed a letter to Nature in 2010 supporting kin selection, this would seem to be the coup de grâce effectively sending group selection the way of the dodo. But, at the same time, it seems odd that so many prominent scientists would feel the need to forcefully defend what they all maintain is an irrefutable, textbook understanding of evolutionary biology. After all, science advances based on empirical evidence, not rhetoric (“An ounce of algebra is worth a ton of verbal argument,” as Haldane noted). Shouldn’t it therefore be an easy task to simply examine the evidence for group selection and leave it at that? Yes, it should in theory. But this is where things get complicated.

“The root of the problem is the existence of several different frameworks for modelling the evolution of social behaviour,” says Samir Okasha, philosopher of science at Bristol University in England, writing in the October 7, 2010 edition of Nature. “The relationships between these frameworks are sometimes ambiguous, and biologists disagree about which is most fundamental and which most useful empirically.”

In other words, the evolution of altruism is under dispute because of how it it is being measured. Therefore, in order to understand what the conflict is fundamentally about it is necessary to go back to the theoretical basis for these different evolutionary concepts. This, of course, leads us to honeybees.

The Sting of Altruism

When I was a boy, long before my professional interests in evolutionary anthropology and the history of science, my friends and I would frequently take hikes in the canyon just beneath the small mountain town in northern California where I grew up. At the base of the incline, bordered in the summer by golden fields of blooming Centaurea solstitialis flowers, was a little heart-shaped lake that you could see from my house. But to reach the lake and swim meant crossing through several football fields of these flowers, known as yellow star-thistles, whose stems were ringed with inch long spines that felt like needles on our hairless legs.

As if that weren’t enough, the owner of the land thought he’d take advantage of this invasive weed on his property by establishing beehives in the nearby forest shade. My friends and I used to joke that you could only tell the difference between getting stung by a bee or stuck with a spine because a bee sting left a blue welt afterwards. Once, as we were wading through these star-thistles on a hot summer day, a bee stung my nextdoor neighbor. As he stood there screaming we all turned to watch in horror as the bee remained stuck to his arm, buzzing incessantly. After what seemed like minutes (but was probably only about ten seconds) the insect broke free only to dive bomb to the ground dead, her viscera yanked from her body on this suicide mission to protect the colony.

What I didn’t know at the time was that the altruism displayed by the eusocial insects in the Hymenoptera (bees, wasps, and ants) was an enormous problem for Charles Darwin. As he wrote in On the Origin of Species, an act of self-sacrifice that only served to benefit another was a “special difficulty” that could potentially undermine his theory of natural selection.

The central premise of Darwin’s theory was that all characteristics of a species–whether physical, like the elaborate antlers of an Irish Elk, or behavioral, like the formation of a V-shaped flock in migratory geese–were traits that had evolved through successive, slight modifications passed down over many generations. Because these modifications would only be passed on if they were beneficial, any trait that brought harm to their possessor would ultimately be discarded. “Natural selection acts solely by and for the good of each,” Darwin wrote. Therefore, any characteristic that violated this premise “would be absolutely fatal to my theory.” With the eusocial Hymenoptera, not only do individuals sacrifice themselves for the group, the vast majority of colony members have given up reproduction altogether.

Darwin’s solution to the problem is what today would be called multilevel selection in which certain traits are selected because they are advantageous at the individual level while others are advantageous at the family or group level. In both cases, the trait is selected because it allowed more offspring to be born who carried that particular trait. As Darwin wrote:

[W]e can perhaps understand how it is that the use of the sting should so often cause the insect’s own death: for if on the whole the power of stinging be useful to the community, it will fulfill all the requirements of natural selection, though it may cause the death of some few members.

It would take more than a century for Darwin’s “special difficulty” of altruism to be tested empirically and, when it was, the great naturalist was considered to be only half right.

Family Values

William D. Hamilton

William D. Hamilton. Photo by Richard Alexander, Wikimedia Commons

While Darwin was a gentleman scholar, a man whose social life was concerned with pedigree and the ties between aristocratic families, William Hamilton was a rugged individualist. This highly influential British biologist, whom Richard Dawkins has called “a good candidate for the title of the most distinguished Darwinian since Darwin,” was just as comfortable hacking his way through the jungles of Brazil with a machete as he was calculating sex-ratios among fruit flies. At public lectures Hamilton was fond of telling the story about how he once jumped overboard to plug a hole with his finger while on a field trip down the Amazon, dryly noting that the dangers of piranhas were much overrated.

In 1964 Hamilton published two papers titled “The Genetical Evolution of Social Behavior” that revolutionized the field of evolutionary biology by suggesting a “gene’s eye” view of the world. By looking at the interests of genes, not just individuals, Hamilton argued that the altruism of honeybees could be explained by calculating the likelihood that an individual’s genes would be shared by close relatives. His equation was beautiful in its simplicity. By multiplying the genetic relatedness of the individual being helped (r) by the reproductive benefit received (B) the equation could predict whether or not it would be worth the reproductive cost (C) incurred as a result, or rB > C. Just like J.B.S. Haldane’s anecdote in the introduction, the evolution of altruism was ultimately a numbers game. If you wanted to maximize your genetic stock portfolio, nepotism paid the highest dividends.

However, the real breakthrough was when this equation was applied to the unique reproductive system of the eusocial Hymenoptera, what biologists refer to as haplodiploidy. In honeybees, for example, male drones receive all of their genes from their mother (haploid) while female workers receive half of their genes from their mother and half from their father (diploid). If queens mate with only one male it means that, on average, they will share 50% of their genes with daughters but each daughter will share 75% of these genes with their sisters (all of their father’s genes and half of their mother’s). Female honeybees are therefore genetically closer to their sisters than they would be to their own offspring. Rather than breed themselves it was in their genetic interest to be sterile and, in Hamilton’s words, use their mother as a “sister-producing machine.”

Haplodiploid sex determination system

Haplodiploid sex determination system. Image created by Mo-rin, Wikimedia Commons

This haplodiploidy breeding system, when combined with Hamilton’s equation, also meant that a female worker bee would be predicted to accept enormous costs, even death, to promote the interests of her sisters. After all, what use is your own genetic endowment when you’ve got hundreds, or even thousands, of sisters back at the hive that each share three-quarters of your hereditary sum? The moral math is unambiguous and that group of boys approaching through the star-thistles could mean trouble.

But there was one scientist in 1960s England who was deeply troubled by Hamilton’s equation. George R. Price, a scraggly young chemist and divorcé with a brooding penchant for existential angst, had traveled from New York to London to create a new life for himself. When he encountered Hamilton’s papers in the Journal of Theoretical Biology he decided that altruism was just the question on which he would stake his claim. Perhaps it was because he had abandoned his two daughters, or perhaps it was because he held anti-war views in a world teetering between rival superpowers, but Price had serious concerns about a model for altruism that was based on nothing more than selfish nepotism. He became determined to prove Hamilton wrong.

Thus began one of the most profoundly strange relationships in scientific history (see the wonderful book The Price of Altruism by Oren Harman for more on this fascinating story). By teaching himself the mathematics necessary for his task Price found inspiration in the concept of covariance in order to show how a trait would evolve from one generation to the next. He designed an equation that calculated how a specific trait would covary with its fitness (i.e. the number of copies passed on). While this was little more than an accounting method, what it meant was that altruistic genes could therefore be tracked without relying on relatedness. In essence, Price revealed that Hamilton’s equation was incomplete.

However, Price didn’t stop there. By then calculating what the likelihood was that a trait would be passed on, the Price equation could predict how a trait would evolve over time and could also track multiple levels of selection (from gene to individual and from individual to group). A year after Price had begun working he finally had his answer and wrote to Hamilton about the covariance equation he’d derived. Hamilton called him the very next day.

As Hamilton recalled in his memoir Narrow Roads of Gene Land (p. 172-73), he listened as a squeaky voice on the other end of the line asked him, “Have you seen how my formula works for group selection?”

A Group By Any Other Name

The Social Conquest of Earth

In his book Naturalist, first published in 1994, E.O. Wilson describes himself as a social conservative in both politics and morality. “I cherish traditional institutions, the more venerable and ritual-laden the better,” he says. While Wilson may hold firm to the bedrock of traditional values in his personal life, in his latest scientific work he has taken on the role of a bomb-thrower.

Wilson was once one of the central proponents of kin selection theory, even standing side by side with Hamilton in front of a hostile academic crowd to defend the idea. But now he has abandoned this model and adopted what many perceive to be its mirror opposite. As he writes in The Social Conquest of Earth:

“Inclusive fitness is a special mathematical approach with so many limitations as to make it inoperable. It is not a general evolutionary theory as widely believed, and it characterizes neither the dynamics of evolution nor the distribution of gene frequencies” (p. 180).

However, one important reason for his change is the very reason he adopted kin selection in the first place: the haplodiploidy reproductive system of the eusocial Hymenoptera. At the time when Hamilton applied his equation to these insects the evidence seemed clear that queens would only mate with a single male and it was this that allowed such a high level of relatedness between sisters. However, if you increased the number of matings all bets were off. Sisters might then be no more related to each other than they would be to their own offspring and sterility wouldn’t make evolutionary sense.

As Wilson points out, there have been many studies demonstrating that multiple matings occur in queens among the eusocial Hymenoptera. For example, one study published in Proceedings of the Royal Society by Arnaud Estoup and colleagues in 1994 found that in five different colonies of honeybees (Apis mellifera) there were between 7 and 20 fathers, making female workers related to their sisters by only about 30%. Likewise, another study published in Proceedings in 1999 led by Jacobus Boomsma found that queens in the leaf-cutter ant (Acromyrmex octospinosus) mated with between 4 and 10 males, giving a genetic relationship between sisters of about 33%. Another study published in the journal Evolution by Michael Goodisman and colleagues found that queens in the eastern yellow jacket (Vespula maculifrons) mate with between 3 and 8 males. Further research has suggested that genetic diversity within a colony is important for resisting disease. However, not all biologists think these cases ultimately challenge kin selection in the eusocial Hymenoptera.

Wilson also points out that multiple other eusocial species have been discovered since Hamilton’s study that do not have a haplodiploid reproductive system, including termites (previously thought to be explained under the kin selection model). Others include a species of platypodid ambrosia beetle, several lines of synalpheid sponge-dwelling shrimp, as well as two species of bathyergid mole rat.

“The result was that the connection between haplodiploidy and eusociality fell below statistical significance,” Wilson writes. “Consequently the haplodiploid hypothesis has now been generally abandoned by researchers on social insects” (p. 170).

Wilson’s solution then is to also abandon kin selection as a category and explain eusocialty through multilevel selection like Darwin did. Since individuals are expected to adapt behavioral strategies that maximize their fitness, species that live in groups have done so because it was in each individuals reproductive interest. However, because there will always be a tension for group-living species between what can be called selfish behaviors and groupish behaviors, multilevel selection means that different traits will be subject to different selection pressures towards one pole or the other. For most species the result will end up being a compromise that benefits each individuals overall fitness in relation to their group. However, in special cases, natural selection will push a species towards one extreme or the other.

As E.O. Wilson explained in a paper co-authored with David Sloan Wilson (no relation) in 2007 for the Quarterly Review of Biology (pdf here), multilevel selection is best understood by using what are referred to as vectors in physics. The simplest way to visualize this is to imagine a toy boat on one side of a river that has two strings being pulled simultaneously by children at different points on the other side. If both children pull with the same amount of force the boat will end up directly between them. However, if one child is larger and pulls the string with more force, the boat will end up closer to one than the other.

Wilson therefore believes that abandoning Hamilton’s equation and embracing a multilevel approach like the Price equation would be the most reasonable, and parsimonious, way to move forward.

“If there is a general theory that works for everything (multilevel natural selection) and a theory that works only for some cases (kin selection), and in the few cases where the latter works it agrees with the general theory of multilevel selection, why not simply stay with the general theory everywhere?” (p. 175).

Ironically, most of Wilson’s critics tend to agree, they just use this same argument for retaining kin selection and rejecting group selection. The three most common critiques of Wilson’s position in the scientific literature are that: 1) Group selection models are functionally equivalent to kin selection (Lehmann, 2007; Marshall, 2011) 2) Kin selection models are precise while group selection is ambiguous (Mallet, 2010; West et al, 2011), and 3) Kin selection is supported by empirical studies while there is no evidence to support group selection (Bourke, 2011 as well as the recent online critiques by Dawkins, Pinker, and Coyne).

The first critique is conceded on both sides and could apply equally to both. So, then, what is the group selection model and is there any evidence to support it?

All For One, One For All

Imagine a simple system, like a petri dish of E. coli for example. Now suppose there was a simple genetic trait that offered benefits to other cells but brought a cost to the individual producing it, perhaps a gene that promoted antibiotic resistance for cells nearby. Theoretically, if a cell had this gene it would benefit its daughter cells and the trait would spread. But then, of course, there’s the problem of free riders. Even if this altruistic trait was extremely successful in the population, wouldn’t the emergence of even a single selfish cheater destroy everything? The cheater would benefit from the antibacterial resistance produced but wouldn’t give anything back, meaning they would end up leaving more daughter cells than the altruists. Continue this pattern a few more generations and wouldn’t the altruists be completely eliminated? Not necessarily.

A prediction of the Price equation is that altruistic groups will ultimately be more successful than selfish groups under certain conditions, even though selfish individuals could outcompete altruistic individuals. Imagine the same petri dish as before but this time cells randomly congregate into a large number of mixed groups containing both altruists and cheaters. Two things will now be expected to happen. Because altruists are at a disadvantage they will reproduce more slowly than the cheaters as a result of within-group competition. However, the benefit provided by the altruists means that those groups who accidentally have more altruists will grow faster and end up having more total cells than groups composed mostly of cheaters. Because the altruistic group as a whole ends up being more successful there will be an overall increase in the number of altruistic individuals in the total population. Bring all the cells together to form random groups again and eventually you could have groups, as well as an entire population, composed only of altruists.

Evolution of Microbial Altruism

Evolution of microbial altruism occurs when 1) randomized groups of altruists and cheaters are formed, 2) these undergo group evolution, and 3) groups are merged in order to repeat the process. Image reproduced from Cremer et al. (2012).

At this point it should be pointed out that this model isn’t simply theoretical but represents the empirical results of a study published on January 9, 2009 by John Chuang, Olivier Rivoire, and Stanislas Leibler in the journal Science (and was successfully replicated earlier this year in Nature). Based on this example it should be clear that there could be no preference towards relatives (i.e. daughter cells) to explain the results because the altruism involved was broadcast indiscriminately. The evolution of the altruistic trait in this case was based on association, not kinship.

Coming Home to Roost

When William Hamilton received the covariance equations from George Price in the late 1960s he recognized the inherent limitation in his model of inclusive fitness (“everyone makes a mistake now and then,” Price told him). However, this was more than compensated for by the extension that Price’s equation now offered. As Hamilton wrote in his memoir (p. 173):

Some months before he died I was on the phone telling him enthusiastically that through a ‘group-level’ extension of his formula I now had a far better understanding of group selection and was possessed of a far better tool for all forms of selection acting at one level or at many than I had ever had before.

“I thought you would see that,” the squeaky laconic voice said, almost purring with approval for once.

Just after Christmas in 1974 George Price died after he jabbed nail scissors into his neck and snipped his carotid artery. By this point he had given up evolutionary biology and was living in an abandoned building as a squatter with the homeless alcoholics he had been trying to rehabilitate. A few months after attending his funeral Hamilton published his little known paper entitled “Innate Social Aptitudes of Man: An Approach from Evolutionary Genetics” in the edited collection Biosocial Anthropology where he used the group selection component of Price’s covariance equation. In this paper he proposed that inclusive fitness should now be understood as a multilevel selection approach in which there is a nested hierarchy extending from genes, to individuals, to kin, and finally to groups.

Because of the way it was first explained, the approach using inclusive fitness has often been identified with ‘kin selection’ and presented strictly as an alternative to ‘group selection’ as a way of establishing altruistic social behaviour by natural selection. But the foregoing discussion shows that kinship should be considered just one way of getting positive regression of genotype in the recipient, and that it is this positive regression that is vitally necessary for altruism. . . But it seems on the whole preferable to retain a more flexible use of terms; to use group selection where groups are clearly in evidence [whereas] ‘kin selection’ appeals most where pedigrees tend to be unbounded and interwoven, as is so often the case with humans.

In Hamilton’s suggestion, which is virtually identical to multilevel selection as David Sloan Wilson presents it today, group selection should be reserved only for those cases where the altruistic behavior cannot be explained by kin selection. In contrast, E.O. Wilson wants to do away with kin selection because the group selection equations reach the same result anyway. Ultimately, Wilson’s argument is about reducing the number of steps between the levels of gene and group. While it is possible that Wilson has a point for the eusocial Hymenoptera (though this remains to be seen), the utility that kin selection has for other species–particularly primates–remains strong, meaning that Wilson probably overreached. As for multilevel selection more generally, there seems to be no reason why Hamilton’s suggestion for a “gene’s eye” view of group selection shouldn’t be considered when the necessary conditions are met.

There have been multiple empirical studies that scientists argue support a group selection approach. Charles Goodnight and Lori Stevens reviewed many of these in The American Naturalist in 1997 and David Sloan Wilson has discussed others online and in his book Unto Others: The Evolution and Psychology of Unselfish Behavior co-authored with Elliot Sober. This evidence (as well as that from additional studies) should be scrutinized to determine whether it supports such claims or not, but it nevertheless represents the empirical results necessary for building a scientific theory.

In the final analysis, multilevel selection is little more than a rebranding of Hamilton’s inclusive fitness (albeit the “enhanced” 1975 version). So is that what this fight is really all about, the objection over a name change? On a superficial level, yes, but there are larger stakes involved. Consider the case of Pluto. When the International Astronomical Union demoted Pluto from its longheld status as a planet in 2006 it was met with outrage. Even something as simple as a name change must face the reality of textbooks that have to be rewritten, professional reputations that are invested in the status quo, funding opportunities that could be lost, as well as a theoretical shift that some scientists may be unwilling to make. As the physicist Max Planck once quipped, and Richard Dawkins has repeated, “Science advances one funeral at a time.”

But this is simply how the scientific process works. Boundaries are tested and concepts are challenged. If a theoretical framework remains internally consistent it will gain more adherents while disputes within other frameworks may cause them to dwindle and ultimately disappear. There is a rich fossil record of unsuccessful ideas–from phlogiston to Lysenkoism–that litter the field of our scientific past. If nothing else, the modern conflict over altruism will help us ensure that the best ideas are passed on to the next generation. It’s a good fight to have.

Eric Michael Johnson About the Author: Eric Michael Johnson has a Master's degree in Evolutionary Anthropology focusing on great ape behavioral ecology. He is currently a doctoral student in the history of science at University of British Columbia looking at the interplay between evolutionary biology and politics.

Follow his work on Facebook and Google+. Follow on Twitter @primatediaries.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. Hakusan 5:32 pm 07/9/2012

    When one feels deep kindness for a dying moth, is that “altruism”?

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  2. 2. ghoelzer 6:25 pm 07/9/2012

    Hakusan – I think part of the epistomological problem in this area is the focus on ‘altruism’, rather than sociality. To answer your question, I would say such a feeling for a moth would not be labeled ‘altruism’, but it probably is a result of the fact that your own evolutionary lineage has led to perceptions consistent with social living.

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  3. 3. EricMJohnson 7:36 pm 07/9/2012

    It entirely depends on whether you would be willing to sacrifice your own reproductive potential to make sure the dying moth increased theirs. That’s the biological definition of altruism.

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  4. 4. marclevesque 8:14 pm 07/9/2012

    Thanks. Amazing read.

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  5. 5. Barkley Rosser 4:20 am 07/10/2012

    Interesting piece, but unfortunately it repeats a widespread myth, that Price originated the idea of looking at covariance to study multi-level selection as codified in the so-called Hamilton-Price equation.

    That honor should go to the late James F. Crow, who just died at 95 this past January, the last link to the neo-Darwinians, particularly Sewall Wright. Crow originally published his equation in 1955 in “General Theory of Population Genetics: Synthesis,” Cold Harbor Symposia on Quantitative Biology, vol. 20, pp. 54-59.

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  6. 6. EricMJohnson 4:50 am 07/10/2012

    Thanks for your comment and for the citation to Crow’s paper (which can be seen online here with an institutional subscription: http://j.mp/NhJ1Tf). However, I didn’t say anything about Price originating this idea. I wrote that he found inspiration in using covariance to address the question of altruism. My piece was ultimately about the Hamilton-Price equation, though I completely agree that Crow’s work was an important contribution to the theoretical development of population genetics. The website Panda’s Thumb wrote a nice obituary in Crow’s honor earlier this year: http://j.mp/NhK3OY

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  7. 7. geojellyroll 7:52 am 07/10/2012

    EO Wilson has always been a contradiction: one of the keenest observers of natural history while at the same time one of the poorest interpreters of what he observes.

    Over 30 years ago a group spent a couple days with him observing ants. My wife and I learned so much from him….however… we are both geologists and not entymologists but even so we would shake our heads at some of his ‘scientific’ interpretation that seemed more like fanciful educated speculation.

    Congrats to Dawkins and others for taking on the undeserved status Wilson has as interpreter of evolution…too many in the past have put Wilson on a pedestal and deferred to his misguided ramblings.

    Wilson, like S.J. Gould, incorporates an almost anthropomorphic political correctness into his behavioral analysis. Dawkins, like the guy or not, is diligent in at least trying to keep human-centered interpretation as far away from science as possible (as is possible being human).

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  8. 8. oharar 7:56 am 07/10/2012

    But in the last few years an academic turf war has developed pitting the supporters of inclusive fitness theory (better known as kin selection) against a handful of upstarts advocating what is known as group selection, the idea that evolutionary pressures act not only on individual organisms but also at the level of the social group.

    I don’t think anyone denies that selection can operate at the social group level. I think the debate revolves around 2 issues:

    1. Should we use multi-level fitness or inclusive fitness to analyse interactions? Almost everyone agrees that they are formally equivalent only 3 people in the field disagree). Most of the people active seem to agree that inclusive fitness is easier in practice, but there was an amusing back and forth a few years ago where one guy admitted he used multi-level fitness for the analysis of a problem, because he found it easier, and the response (and this had Laurent Lehmann’s fingers all over it) was to explain the inclusive fitness approach. But there was no cries of “heathen!”. I must have the references somewhere.
    2. Does group selection occur in nature? I think the consensus here is that it does, but it’s not that common. There are certainly examples, but everyone is scared of calling it “group selection”, which is ridiculous.

    Honestly, this is a debate that should be left to die, so we can get on with some more interesting stuff.

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  9. 9. Descarreaux 8:00 am 07/10/2012

    I always thought that the monarch butterfly needed group selection theory.

    I do not talk about the viceroy’s mimicry. But the monarch specie.

    Am I right?

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  10. 10. jvkohl 10:21 am 07/10/2012

    The problem with multi-level selection in humans seems likely to be one that is due to ignorance about the role of pheromones in the context of ecological, social, neurogenic, and socio-cognitive niche construction. The honeybee model organism best exemplifies the multi-level selection that enables adaptive evolution via natural selection for nutrient chemicals that metabolize to pheromones (species-specific chemical signals, that control reproduction).

    What the honeybee queen eats determines her pheromone production and everything else about interactions among the colony members, including the neuroanatomy of the worker bees’ brains. But the molecular biology that allows selection for nutrient chemicals and their metabolism to pheromones is the same in species from microbes to man.

    Sensory input must epigenetically effect intracellular signaling and stochastic gene expression, or else adaptive evolution via pre-existing genetic variation and ecological, social, neurogenic, and socio-cognitive niche construction cannot occur. Why then does EO Wilson not simply move forward with his eusocial insect model of group selection, and extend it to humans? There’s no other model for that. Is there?

    Isn’t the lack of another model the problem here? And why on earth (i.e., this planet) would anyone use one model of group selection for insects, but propose that there must be some other model (nest-building) for mammals, like us?

    Kohl, J.V. (2012) Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors. Socioaffective Neuroscience & Psychology, 2: 17338. DOI: 10.3402/snp.v2i0.17338. http://dx.doi.org/10.3402/snp.v2i0.17338

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  11. 11. jrvz 10:26 am 07/10/2012

    I know very little about the theory of evolution, but the following statement caught my eye “Taken together, along with the 137 scientists who signed a letter to Nature in 2010 supporting kin selection, this would seem to be the coup de grâce effectively sending group selection the way of the dodo.”

    I would like to know since when has the validity or otherwise of a scientific theory been decided by majority vote? How many scientists “voted” Wegeners theory of Continental Drift wrong.

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  12. 12. EricMJohnson 10:56 am 07/10/2012

    @jrvz: According to Dawkins, the 137 dissenting scientists matter because “one can make a good case that the 2010 paper would never have been published in Nature had it been submitted anonymously and subjected to ordinary peer-review, bereft of the massively authoritative name of Edward O Wilson. If it was authority that got the paper published, there is poetic justice in deploying authority in reply.” I referenced this because it so often comes up during the debate.

    However, my own view would be the same as Albert Einstein’s after he learned that around one hundred authors had published papers critiquing his theory of relativity: “If the theory is wrong, why wouldn’t one author suffice?”

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  13. 13. geojellyroll 2:06 pm 07/10/2012

    “If the theory is wrong, why wouldn’t one author suffice’

    Because Wilson spews out his ‘social’ biology that is spinned from specualtion. Disproving Wilson is like disproving Santa Claus.

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  14. 14. EricMJohnson 2:41 pm 07/10/2012

    @geojellyroll: Kindly refrain from ad hominem attacks. Either present evidence to support your arguments or take them elsewhere. You’re representing science after all.

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  15. 15. steevo 2:59 pm 07/10/2012

    How can anyone write an article on the evolution of altruism and not even mention Robert Trivers theory of reciprocal altruism, which, at least among primates, is supported by a large body of empirical evidence?

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  16. 16. Barkley Rosser 3:08 pm 07/10/2012

    Thanks for the Panda’s Thumb link on Jim Crow, Eric. My late mother used to play violin with him in the Madison Symphony Orchestra as well as in string quartets. He was indeed the gentleman and scholar many described him to be.

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  17. 17. ThePeakOilPoet 4:07 pm 07/10/2012

    The honey bee would not even be an issue if either of the following was true

    1. drones contributed to the gene pool directly (and so could pass on a mutation that resulted in them not loosing their sting), or

    2. a mutation in a queen led to the same result

    seems to me that the mistake being made is to define drones as individuals when it might be more illuminating to see them as little more than extensions to a queen – like unconnected hands or even like hair or fingernails

    it is in the nature of bees to sting to protect their hive but evolution has not provided a simple mechanism for them to evolve away from “self sacrifice”

    so the mistake is to look for a mechanism to explain how self-sacrifice has evolved rather than to look for reasons as to why it has not disappeared from the gene pool

    pop

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  18. 18. Cooperator 9:16 pm 07/10/2012

    I’ve been thinking about these problems for a few years from a mathematical point of view. I think that the Price equation (or Price-Hamilton equation) does not properly charactarize group selection. If you look at the equation you will see that the set of groups is the same before and after the change. So, events like groups dying or breaking into pieces are not accounted for properly. Only differential group growth rates are accounted for. But group-level events are crucial to group selection, so the standard mathematical theory is flawed. There are some new videos on YouTube that show how group selection works by animating the dynamical equations for two-level population processes. Type “group selection PDE” or “group selection hybrid solution” or “group selection simulation” at YouTube, and I think you will find them.

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  19. 19. Helian 9:39 pm 07/10/2012

    Group selection has an interesting history. Dawkins wrote in the first chapter of The Selfish Gene that Robert Ardrey, Konrad Lorenz, and Irenaus Eibl-Eibesfeldt, all of whose reputations were considerably greater than his at the time, were “totally and utterly wrong” because they believed in group selection. Steven Pinker then wrote an entire book about the Blank Slate that mentioned Lorenz very little, and Ardrey in only one paragraph, justifying this strange procedure by referring to Dawkins “totally and utterly wrong” comment, without even mentioning that it was connected to group selection.

    Whatever you think of Ardrey, he was by far the most significant and effective opponent of the Blank Slate in its heyday. The Blank Slaters admitted as much themselves in “Man and Aggression,” edited by Ashley Montagu and published in 1968, a book mainly intended as an attack on Ardrey. For example, from the essay by Geoffrey Gorer, a noted anthropologist at the time:

    “Almost without question, Robert Ardrey is today the most influential writer in English dealing with the innate or instinctive attributes of human nature, and the most skilled populariser of the findings of paleo-anthropologists, ethologists, and biological experimenters… He is a skilled writer, with a lively command of English prose, a pretty turn of wit, and a dramatist’s skill in exposition; he is also a good reporter, with the reporter’s eye for the significant detail, the striking visual impression. He has taken a look at nearly all the current work in Africa of paleo-anthropologists and ethologists; time and again, a couple of his paragraphs can make vivid a site, such as the Olduvai Gorge, which has been merely a name in a hundred articles.

    “…he does not distort his authorities beyond what is inevitable in any selection and condensation… even those familiar with most of the literature are likely to find descriptions of research they had hitherto ignored, particularly in The Territorial Imperative, with its bibliography of 245 items.”

    In a word, Pinker wrote a tome against the Blank Slate that dismissed its most effective opponent as “totally and utterly wrong,” because of group selection! That is, at best, ridiculous. The theme of all Ardrey’s work was the existence and significance of human nature, not group selection. Perhaps Pinker’s rather hurried response to Wilson’s latest reflects his bad conscience. Ardrey was anything but the “killer ape” bogeyman the Blank Slaters invented, and it seems to me that he doesn’t deserve to be airbrushed out of history.

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  20. 20. fellowearthling 12:30 am 07/13/2012

    for the defensive action of an individual honeybee to be considered ‘altruistic behavior’ it must be assumed that the individual is aware of its pending self-sacrifice. i have been stung by honeybees, wasps, and hornets and bitten by fire ants for being in too close proximity to their nests. honeybees are the only ones who die as a result of their defensive action (discounting the ones crushed by the angry hand of the stingee), being the only ones with a barbed stinger. only the workers are so equipped. a honeybee queen (who is solely responsible among the hive females for passing on any genetic traits) has no barb and can sting repeatedly with impunity. so, wherein lies any connection of altruistic self-sacrifice with genetics in eusocial insects? if honeybees are simply behaving like other eusocial insects, defending the nest cannot be interpreted as altruistic. examining the behavior of insects may not be fruitful in the search for a genetic origin of kindness.
    may i suggest that true altruism must predicate on awareness within the individual of the consequences of his/her behavior? if so, we must examine the origins of awareness and its complex social effects before beginning to understand the origins of kindness.
    it seems somehow intuitive that simple mathematical equations cannot suffice.

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  21. 21. EricMJohnson 3:10 am 07/13/2012

    @fellowearthling: The dictionary definition of altruism may be based on self-awareness but if we want to understand how altruism could evolve (and there’s no doubt that it has in many non-human species) we need to remove self-awareness from the definition. Honeybee workers have foregone reproduction and will sacrifice themselves for the benefit of the group. That is the ultimate act of altruism in the animal world. If we want to understand the origins of altruism in other species honeybees offer an excellent model for scientific study.

    As for your second point, science is based on measurement and statistical analysis. Without mathematical equations there would be no science. It’s that simple.

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  22. 22. Ralph Haygood 6:43 pm 10/3/2012

    This strikes me as a good exposition of the situation. The only part I can’t agree with you about is, “It’s a good fight to have.” Essentially the same fight has been going on for years and years and years. Much the same arguments were flying around when I started on my Ph.D. (population biology, U. C. Davis, 2002) way back in 1997, and they were hardly novel even then. Moreover, in my judgment, most of the arguing generates more heat than light. As you acknowledge, the arguments are, to a large extent, over what to name things. Mathematical modeling makes that clear, but the arguing tends to be more verbal than mathematical. And in my experience, nothing else in evolutionary biology except maybe species concepts tends to bring out the bitterness the way this mess does (e.g., I recall being informed by a candidate for a postdoc at Davis that Sober and Wilson had done “a great disservice to science” by publishing their book). Enough! People who prefer multilevel-selection approaches should use them, and people who prefer kin-selection approaches should use them, and they should stop throwing bombs at each other. (Also – my personal preference – whenever possible, do old-fashioned, Haldane-style population genetics and let other people worry about whether it should be called kin selection or something else.)

    Incidentally, what led me here today was your piece in Slate, which I think is an excellent piece about important topics.

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  23. 23. upload70 4:26 am 10/10/2012

    Jabbing nail scissors into your neck and snipping your carotid artery doesn’t sound like a typical suicide. http://buysteroidsuk.co/

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  24. 24. aldarwin 2:26 pm 10/15/2012

    Why could not two (several/many) models of “fitness” have arisen, some still extant, all resulting from local conditions over geologic time… after all fish swim. Altruism if successful could be arrived at by more than one route.

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  25. 25. ABlack 12:09 pm 12/13/2012

    kindness seems like the natural thing to do even from a very young age kids seem to get pleasure from performing what adults perceive as kind acts to each other. buy sarms

    Link to this

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