race/history/evolution notes: altruism

Showing posts with label altruism. Show all posts

Sewall Wright on race differences, group selection, and cultural selection among humans (1978)

[From Evolution and the Genetics of Populations, Volume 4: Variability Within and Among Natural Populations, pp. 439-457]

Racial Differentiation in Mankind

The existence of conspicuous diversity among human populations in physical appearance has been common knowledge at least since the time of ancient Egypt. The subject is discussed at length in numerous books on physical anthropology and need not be considered here in detail.

There is no question that all mankind constitutes a single species in view of the absence of any physiological bar to hybridization between the most diverse races or of any recognizable loss of vigor in the first or later generations.

There is also no question, however, that populations that have long inhabited widely separated parts of the world should, in general, be considered to be of different subspecies by the usual criterion that most individuals of such populations can be allocated correctly by inspection. It does not require a trained anthropologist to classify an array of Englishmen, West Africans, and Chinese with 100% accuracy by features, skin color, and type of hair in spite of so much variability within each of these groups that every individual can easily be distinguished from every other.

[. . .] It has been indicated earlier that such an evolutionary process as that of man is much more understandable if it occurred by the shifting balance process. Simultaneous sampling drive at thousands of sufficiently neutral loci provides different material in innumerable localities without appreciable cost, material that can give the basis for effective interdeme selection.

Was the population structure of primitive man favorable to this process? There have been a number of studies of the few remaining peoples at the hunting and gathering level of culture that bear on this matter. Birdsell (1972), in an intensive study of Australian aborigines in western Australia, has described their population structure. The primary territorial unit is the band, consisting of a group of related families. Marriage is exogamous but largely restricted to the tribe, a group of bands in which the same dialect is spoken. He estimates the average total number in a tribe to be about 500, with a breeding population of about 185 and an effective number of about 100. This is small enough for the building up of considerable differences among large areas at each nearly neutral polymorphic locus merely by sampling drift. There is thus the basis for operation of the shifting balance process. [. . .]

The actual process of interdeme selection may take different forms. At one extreme, the local appearance of a superior genetic system is followed by expansion of its territory accompanied by complete elimination of its neighbors until it occupies the entire range of the species. At the other extreme there is merely excess diffusion from the superior center. Neighboring populations are graded up until they reach the point (the crossing of a saddle in the surface of selective values) at which mass selection carries them autonomously to the new selective peak, or perhaps beyond, if they contribute something that improves on the latter. The locations of the population with the highest selective peak may shift from place to place in the course of time, as a group of neighboring populations step each other up to heights well above the general level.

Bigelow (1969) has emphasized the importance of tribal warfare in the operation of this process. A tribe that is generally successful because of superior intelligence, capacity for cooperation, and high frequency of the heroic virtues as well as physical prowess, tends to increase its territory and also to grade up what is left of the defeated group by hybridization. The process is illustrated by the incessant tribal warfare of the tribes of American Indians observed by the European settlers in America, in which some tribes such as the Iroquois expanded at the expense of their neighbors.

The heroic virtues, including willingness to sacrifice one's own life for the good of the tribe, are traits that can hardly be developed (insofar as they have a genetic basis) by purely individual selection. They may to some extent arise as a by-product of familial selection in which close relatives with heredities strongly correlated with that of an individual who gives his own life to save them. As noted earlier, the effectiveness of familial selection in general is testified to by the improvement of milk production in cattle and of egg production fowls, mainly by selection of males on the basis of the performance of close female relatives. The importance of this sort of intergroup selection in evolution has been emphasized as noted in chapter 7 by Hamilton. The increase in frequency of traits deleterious on the average to their possessors but beneficial to the deme may also, however, be increased by interdeme selection (referred to as intergroup selection in early articles) if the benefit to the deme sufficiently outweighs the damage to the individual. A more rigorous demonstration of this mode of evolution of "altruistic" characters as been given by Eshel (1972).

Not all interdeme selection in man has consisted of intertribal warfare. According to Birdsell, about 15% of marriage among Australian aborigines were intertribal; not enough as shown by the wide variability of gene frequencies to homogenize the whole population but enough to permit effective interdeme selection if exchange was asymmetrical, predominantly from the more to the less successful. That differences were not swamped was presumably due to the exchange being largely between neighboring tribes which differed little, as indicated by the semiclinal nature of the pattern of gene frequencies. The average effective immigration from the population as a whole, the m of formulas, was thus very much less than 0.15. [. . .]

Evolution Since the Origin of Agriculture [. . .]

We can form a better idea of the course of event than in any earlier period but the interpretation is confused by the exponential progress of a second evolutionary process, barely existent at all in any other animal, and little if any more rapid in the earlier history man than his biological evolution.

This is the evolution of culture with its line of transmission largely from speaker to listener, supplemented in the last three thousand years by transmission from writer to reader. It began to become of major importance with the origin of language, but during the hunting and gathering phase of human life the slow advance of culture is indicated by that in the fashioning of stone tools and weapons. It was probably accompanied by relatively rapid diffusion of knowledge of such advances as were made. The success of tribes thus probably depended to a greater extent on capabilities, determined by their genes, than on the possession of techniques not known to their neighbors.

The mode of evolution of culture is analogous to that of the genetic system. Invention is the analog of mutation. Diffusion of culture is the analog of gene flow. Cultural variation is continually subject to selection on the basis of utility. There is random cultural drift, exemplified by the breaking up of languages into dialects. Finally, the most favorable conditions for cultural advance is local isolation, providing the basis for simultaneous trial and error among many variants and the diffusion of the more successful ones in analogy with the shifting balance process in biological evolution. We think here of the multiple competing cultures in ancient Southwest Asia, the evolution of culture among the city states of ancient Greece, and in much divided Europe from the Dark Ages to modern times. The great empires of the ancient Southwest Asia of Alexander and of Rome constituted an overbalancing final phase in the process, giving widespread diffusion but less progress by trial and error.

There has undoubtedly always been a considerable but incomplete correlation between the two kinds of evolution. The state of the culture has been to a considerable extent an index of the rank of populations genetically in the distinctive human line of evolutionary advance, and reciprocally the demands of culture have been the primary selective agent in this advance in its later stages. Aspects of culture are continually being borrowed, but whether such borrowings are effectively integrated into the existent culture to form new peaks (as most conspicuously in the recent period in Japan), or are adopted only superficially and to the detriment of the previous culture, is also an index of genetic capability.

The treatment of either the genetic capabilities or the cultures of peoples as if they could be ranked on single scales is, of course, a gross simplification. If the multiple genetic aspects of mental ability could be measured more independently of culture than is the case, it would no doubt be found that each local race has its own unique combination of favorable qualities. At present only IQ seems to have a repeatability that permits evaluation of the contributions of genetic and nongenetic variabilities to its variability, discussed in the previous chapter, and this only within a particular culture.

On the other hand there have probably always been wide differences among the peoples of the world in average intellectual ability and cultural level from the standpoint of progress toward the situation in civilized man. This was presumably related to the environmental conditions. Men could not endure the northern winters without fire, the use of which is documented by hearths found in France dating back over half a million years and somewhat later in Hungary and in China but only about one-tenth as far back in Africa (Campbell 1974).

The capacity to anticipate and plan for the future is a mental attribute which would be favored under northern conditions and selected for insofar as it has a genetic basis. This would presumably have come to be more advanced in the temperate zone than in the tropics. [. . .]

Linguistic evidence indicates the establishment of an important center of diffusion in east-central Europe some 5,000 years ago from which wave after wave peoples moved in all directions. The Hittites carried an Indo-European language of the western (centum) type into Asia Minor and established an empire some 4,000 years ago. A thousand years later the Iranians, who had moved east into what is now southern Russia and Turkestan, brought an Indo-European language of the eastern (satem) type into the original cultural center and later established the Persian Empire. They also carried another Aryan dialect to India. Other tribes moving south from the east-central European center reached Greece in several waves which, after mixing with the indigenous people, produced classical Greek civilization.

Other waves moved to the southwest into Italy, giving rise to Latin and other Italic languages; to the west, giving rise to Celtic languages in what is now southern Germany, France, and the British Isles; and to the northwest into what is not northern Germany and Scandinavia, to give rise, in much altered form, to the Germanic languages. Subsequent migrations greatly expanded the areas occupied by derivatives of Latin and Germanic branches at the expense in Europe of the Celtic. All the tribal migrations were undoubtedly accompanied by much intermixture with indigenous peoples, but the diffusion of language also undoubtedly implies considerable gene flow.

[. . .] The history of Europe, especially western Europe, was thus prevailingly one of inflow of genes up to the relatively recent period in which it itself became a center of massive outflow.

Related posts:

Moral parochialism and contextual contingency

Moral parochialism and contextual contingency across seven societies

Human moral judgement may have evolved to maximize the individual's welfare given parochial culturally constructed moral systems. If so, then moral condemnation should be more severe when transgressions are recent and local, and should be sensitive to the pronouncements of authority figures (who are often arbiters of moral norms), as the fitness pay-offs of moral disapproval will primarily derive from the ramifications of condemning actions that occur within the immediate social arena. Correspondingly, moral transgressions should be viewed as less objectionable if they occur in other places or times, or if local authorities deem them acceptable. These predictions contrast markedly with those derived from prevailing non-evolutionary perspectives on moral judgement. Both classes of theories predict purportedly species-typical patterns, yet to our knowledge, no study to date has investigated moral judgement across a diverse set of societies, including a range of small-scale communities that differ substantially from large highly urbanized nations. We tested these predictions in five small-scale societies and two large-scale societies, finding substantial evidence of moral parochialism and contextual contingency in adults' moral judgements. Results reveal an overarching pattern in which moral condemnation reflects a concern with immediate local considerations, a pattern consistent with a variety of evolutionary accounts of moral judgement.

Of interest (and contra those who would predict Westerners would be the outliers):

The seven societies sampled vary in the degree to which moral judgements are parochial and contingent on the pronouncements of authorities. At one extreme, Ukrainian villagers evince strong reductions in judgements of moral wrongness as a function of temporal distance, spatial distance and authority consent. At the other extreme, Yasawan villagers display much smaller changes in judgement, and do so only in response to temporal and spatial distance. Interestingly, although Western liberal democracies often rhetorically espouse universalist moral positions, urban Californians occupied the middle of the spectrum in this regard. In the future, it will be important to explore which social, psychological or historical factors influence the degree of moral parochialism exhibited in a given society.

Reply to RCB on the evolution and adaptiveness of ethnocentric altruism

Continued from this discussion.

"you are unable to explain to a competent person why you believe what you believe."

I'm trying to be patient here, but I don't know how much better I can explain this. You either get it, or you don't. If you don't, you're not as competent as you believe; you either don't really understand the basic concepts we're talking about or have mental blocks when it comes to applying them to humans, and this is something you need to deal with yourself.

No matter how many times I explain this, you don't want to get it. Your starting point is that Salter can't be right; so when I explain to you how your reasoning is flawed, regardless of how many times we go through this or how many times I address a particular objection, your response is just to throw out additional confused reasoning, often forgetting things you previously agreed I was correct on and switching back to objections that have already been addressed.

The benefit of the ethnocentric altruism alleles comes from between-group selection, not within-group selection. Even in the first generation, an allele for ethnocentric altruism can potentially boost its odds of representation in future generations by, for example, reducing the chance of extinction of the group it's found in (whether by contributing to avoiding defeat and extermination by rival groups in an ancestral environment, or resisting replacement-level immigration in the modern world).

It makes no difference whether there is enough between-group relative to within-group competition at modern scales to maintain or grow this sort of variation in the long run (and certainly Hamilton speculated that self-sacrificing altruism would be found at higher levels in tribal people than in the long-civilized). In a particular instance of intergroup competition of the sort we're discussing, ethnocentric altruism alleles attuned to Hamilton's rule would by definition be adaptive.

This will always be true, regardless of scale, and regardless of how often the group is actually faced with the threat of intergroup competition. In the face of such a threat, the alleles (ones that enhance group competitiveness in a generalized fashion and are sensitive to cost, benefit, and relatedness) will be adaptive.

Your argument is somewhat analogous to claiming sickle-cell alleles can't be adaptive (or even exist in the first place!) in a malarial environment because their frequency would not increase in the long run in the absence of malaria. Even if malaria is nearly wiped out and the frequency of sickle-cell alleles begins to decline, this does not prove that if a mosquito with malaria does land on you you'd be better off not having a sickle-cell allele.

"Yes, the behaviors are polygenic. But all genes have to start at low frequency, and you have not explained how they get to high frequency"

Again: positive selection will come from intergroup competition. If your argument is that all relevant variants would be snuffed out immediately, leaving no variation on which group-level selection could act, this is of course absurd. Yet again: we're talking about very large numbers of weakly-selected variants, and a large surface on which new mutations can arise.

Crow and Aoki modeled group selection for polygenic behavioral traits. Again, it boils down to Hamilton's rule.

Group selection for a polygenic behavioral trait: a differential proliferation model [pdf]
Group selection for a polygenic behavioral trait: estimating the degree of population subdivision [pdf]
Our general approach is to use molecular markers, which are selected very weakly at most, as neutral indicators of population structure. G_ST gives us an appropriate description of the relevant aspect of the structure. By using Eq. 3 we can state the maximum value of cost/benefit of a quantitative trait if that trait is to increase in average value or frequency in the population. G_ST describes the present structure of the population; it does not tell us how it got that way. If this value has been roughly stable in the past, we could expect that traits with c/b up to this value would have increased in the population, assuming of course that such traits exist and have heritability greater than zero.

Empirically, ethnocentrism exists, and no doubt has since before we were humans. Empirically, ethnocentrism has heritability greater than zero.

Nature, nurture, and ethnocentrism in the Minnesota Twin Study [pdf]
Common Heritable Effects Underpin Concerns Over Norm Maintenance and In-Group Favoritism: Evidence From Genetic Analyses of Right-Wing Authoritarianism and Traditionalism [pdf]
Genetic evidence for multiple biological mechanisms underlying in-group favoritism [pdf]

Your issue is with reality, not with Salter or me.

"Of course, ethnic altruist genes could be maladaptive relics of the past, when groups were small. But Salter says they are adaptive now."

Again, see above.

And Salter never claims we are well-adapted to ethnic competition in the modern world. If he'd believed that to be the case, he would have had little reason to write the book. From the introduction:

On Genetic Interests is an attempt to answer the empirical question: How would an individual behave in order to be adaptive in the modern world? I adopt the neo-Darwinian meaning of adaptive, which is to maximize the survival chances of one’s genes. I begin by describing humans as an evolved species and thus as creatures for whom genetic continuity consists of personal reproduction or reproduction of kin. [. . .]
Humans can no longer rely on their instincts
There is nothing immutable or necessarily perfect about adaptations or the understanding, appetites and preferences they organize. Natural selection is constrained by evolutionary history and environment. It shapes bodies and behaviours in small increments by modifying existing species. Much in nature is badly designed, if one examines it from an engineer’s viewpoint. [. . .]
Like adaptations that advance them, proximate interests can be imperfect in promoting genetic interests. The main problem is the slowness of natural selection compared to the rapidity of technological and social change since the Neolithic. The inertia of adaptations can cause them to continue to promote proximate interests that no longer serve fitness. For most of humans’ evolutionary history, adaptations tracked slow-moving environmental change, including technological advances. In the species’ distant hominid and pre-hominid past, proximate interests that reduced an actor’s fitness were valued less and less as the genes that coded for such valuation failed to reproduce. For this reason, at most moments in time proximate interests have correlated with ultimate interests because the environment has changed so slowly that physiology and behaviour could keep track with it. Proximate and ultimate interests have been in equilibrium except where rapid changes in environment occurred. The equilibrium applying to humans has been upset in recent generations, so that we can no longer rely on subjectively designated proximate interests to serve our ultimate interest. We must rely more on science to perceive the causal links between the things we value and formulate synthetic goals based on that rational appraisal.
Proximate interests, often reflected in consciously held values, have become increasingly fallible guides to ultimate interests because modern humans live in a rapidly changing world. Humans evolved in small bands consisting of a few families, sometimes grouped into tribes numbering in the hundreds. For most of their evolutionary history humans made a living by hunting and gathering in largely natural environments. They lacked formal organization and hierarchy. Adults coordinated activities by negotiating simple demographic role specializations — by age and sex — on an egalitarian basis with familiar band members. Most information was common. Humans now live in societies numbering in the millions where the great majority of interactants are strangers or acquaintances. They make their living through a great diversity of occupations resulting in radical asymmetries in information. They live and work in largely man-made urban environments. They are formally organized into states administered by extended hierarchies of rank and resources actuated by authoritative commands, impersonal contracts enforced by the state authority, and powerful forms of indoctrination performed by universal education, centralized media and entertainment.

However, to the extent we are able to correctly reason about what would be adaptive in the context of intergroup competition, and act in accordance with this, we have the equivalent of our generalized ethnocentric altruism alleles.

Related:

JayMan continues to talk about things he doesn't understand

In this episode, he's back to insisting "ethnic genetic interests" (which despite having been corrected multiple times he's still unable to correctly define) are "bunk" (emphasis in original):

However, common among people who have a superficial and/or selective understanding of heritable group differences is belief in conveniently inaccurate claims. One of these erroneous ideas that White nationalists in particular have latched on to is the belief in “ethnic genetic interests” – that is, that kin selection has led individuals to favor people of their own race/ethnic group over others. This of course is bunk. Natural selection doesn’t work that way, since individuals within an ethnic group aren’t closely related enough for this to work. This has been explained repeatedly, lately by Misdreavus:
It is impossible for such a thing as a “race altruist gene” to evolve, because sacrificing yourself on behalf of strangers does nothing to increase the frequency of the gene under any set of circumstances. It doesn’t matter if the frequency of a such a gene “magically” originated with a frequency of 4 in 10 Chinese people. The Chinese who don’t have the gene, on average, would have a higher fitness, resulting in the frequency decreasing monotonically over time.
He continues to argue there, which is worth a read for anyone seriously interested in the matter.

After anyone seriously interested in the matter gets done studying the confused rantings of JayMan's gay sidekick, I would recommend they at least take a few minutes to skim the work of the man who coined the term "ethnic genetic interests". Doing so would have saved JayMan and misdreavus at least some measure of embarrassment.

A copy of Frank Salter's On Genetic Interests: Family, Ethnicity, And Humanity In An Age Of Mass Migration is freely available online.

If you want to talk about ethnic genetic interests, read it.

The actual definition of ethnic genetic interests

Frank Salter defines "ethnic genetic interests" as:

The number of copies of a random individual's distinctive genes in his or her ethny, not counting the copies in kin. The size of ethnic genetic interest is relative to the kinship of genetic competitors. When competitors are closely related ethnies, the interest can be relatively small. When competitors are distantly related, especially from different geographical races, ethnic genetic interest can be many orders of magnitude greater than familial genetic interests.

To deny that ethnic genetic interests exist is to deny that human population structure exists (or to hilariously misunderstand basic population genetics). Ethnic genetic interests exist regardless of whether or not one believes group selection has played any role in human evolution and regardless of whether or not people naturally favor others from their own group.

The issue of the degree to which group selection or kin selection favored the evolution of ethnocentric altruism in humans has no bearing on the reality of ethnic genetic interests. It's a separate issue, on which JayMan/misdreavus are also wrong (one can debate the issue, but not on the confused grounds JayMan and misdreavus have attempted to debate it).

Misdreavus's confusion about coefficients of relatedness

One area of confusion for misdreavus in the linked thread:

The coefficient of relatedness between a Swede and a non-related Swede is zero. The coefficient of relatedness between a Swede and a black African is also zero. You simply do not seem to understand this.

I replied at the time:

This is exactly the misapprehension I just got done correcting for JayMan: http://racehist.blogspot.com/2015/02/kinship-coefficients-and-ethnic-genetic.html

The coefficient of relationship is simply twice the coefficient of inbreeding between the hypothetical children of two individuals. Inbreeding is defined relative to some population. It’s often convenient to disregard non-recent inbreeding in calculating coefficients of relationship, but this only makes sense with respect to a particular [approximately random-breeding] population, and, holding the base population constant, a Swede absolutely does not have the same coefficient of relationship to a sub-Saharan as to another Swede. Nor is there any difference in kind between the type of relatedness indicated through Fst and the type shared by close family members.

Even after having it explained to them again, Misdreavus (and apparently JayMan) still failed to understand this very basic concept.

Misdreavus's confusion about the viability of genes for altruism

This is another extremely basic issue: frequencies of genes harmful to an individual's fitness with respect to his group can increase globally if his group expands relative to other groups. If misdreavus had read and understood pretty much anything written about altruism and kin selection or group selection within the past half century, he would have grasped this.

If groups with high frequencies of ethnocentric people expand at the expense of groups with low ethnocentrism, genes for ethnocentric altruism can increase in frequency.

Even misdreavus's (anti-group-selectionist) idol understands this (or did at one point):

Imagine that in much of history, people lived in small groups that often fought with their neighbors. In that sort of situation, selection for group altruism is at least possible, since the group is full of close relatives, while the opponents are less closely related. Both sides are probably members of the same broad ethnic group or race, but that doesn’t matter : only the kinship coefficients matter.

Related:

Robert Axelrod on the evolution of ethnocentrism

The evolution of ethnocentrism (pdf):

Ethnocentrism is a nearly universal syndrome of attitudes and behaviors, typically including in-group favoritism. Empirical evidence suggests that a predisposition to favor in-groups can be easily triggered by even arbitrary group distinctions and that preferential cooperation within groups occurs even when it is individually costly. The authors study the emergence and robustness of ethnocentric behaviors of in-group favoritism, using an agent-based evolutionary model. They show that such behaviors can become wide spread under a broad range of conditions and can support very high levels of cooperation, even in one move prisoner's dilemma games. When cooperation is especially costly to individuals, the authors show how ethnocentrism itself can be necessary to sustain cooperation.
Ethnocentrism is a nearly universal syndrome of discriminatory attitudes and behaviors (Sumner 1906; Le Vine and Campbell 1972). The attitudes include seeing one's own group (the in-group) as virtuous and superior, one's own standards of value as uni versal, and out-groups as contemptible and inferior. Behaviors associated with ethno centrism include cooperative relations within the group and the absence of cooperative relations with out-groups (LeVine and Campbell 1972). Ethnocentric behaviors are based on group boundaries that are typically defined by one or more observable characteristics (such as language, accent, physical features, or religion) regarded as indicating common descent (Sumner 1906; Hirschfeld 1996; Kurzban, Tooby, and Cosmides 2001). Such behaviors often also have a strong territorial component (Sumner 1906). Ethnocentrism has been implicated not only in ethnic conflict (Brewer 1979; Chirot and Seligman 2001), instability of democratic institutions (Rabushka and Shepsle 1972), and war (van der Dennen 1995) but also in consumer choice (Klein and Ettenson 1999) and voting (Kinder 1998). Although ethnocentrism is sometimes used to refer to a wide range of discriminatory behaviors, we will focus on ethnocentric behavior defined as in-group favoritism.
Ethnocentrism is generally thought to involve substantial cognitive ability in indi viduals (Sumner 1906; Simmel 1955; Sherif and Sherif 1956; Sherif 1966; LeVine and Campbell 1972; Hewstone, Rubin, and Willis 2002) and to be based on complex social and cultural inputs. While such factors certainly play a role in much ethnocentric behavior, extensive empirical evidence from psychology suggests the prevalence of a strong individual predisposition toward bias in favor of in-groups, which can be observed even when cognition is minimal and social input very abstract. [. . .]
The main result of the simulation is that the ethnocentric strategy becomes common even though, unlike previous models,3 favoritism toward similar others is not built into the model. In the final 100 periods of ten 2,000-period runs, 76 percent of the agents have the ethnocentric strategy, compared to 25 percent if selection had been neutral (Table 1, row a). This result shows that in-group favoritism based on simple tags and local interactions can overcome egoism and dominate a population even in the absence of reciprocity and reputation and even when "cheaters" need to be suppressed. Not only is ethnocentrism the dominant strategy, but cooperation (donation) is also the dominant behavioral choice: fully 74 percent of interactions are cooperative (Table 1, row a). Cooperation is common because the dominance of ethnocentric strategies is combined with a tendency for neighbors to have the same tag.
The emergence and dominance of the ethnocentric strategy is not a "knife-edge" phenomenon. In fact, its dominance is robust under a wide range of parameters and variations in the model. When any of the following parameters are either halved or doubled, at least two-thirds of strategies are ethnocentric: cost of helping, lattice width, number of groups, immigration rate, mutation rate, and duration of the run (see the sensitivity analysis in Table 1). The ethnocentric strategy becomes just as dominant even when the simulation starts with a full lattice consisting only of egoists, and no immigration is allowed. Another check for robustness is a variant of the model in which an agent can distinguish all four colors, rather than just distinguish ing between its own color and all other colors. Again, the results are very similar, with 80 percent ethnocentric strategies. Surprisingly, the results are also not very sensitive to the possibility that an agent will occasionally misperceive whether the ther agent in the interaction has the same color. Even when agents make this mis take 10 percent of the time, the population evolves to be more than two-thirds ethnocentric. This resistance of in-group favoritism to noise is quite a contrast to studies of reciprocity in the iterated prisoner's dilemma. The tit-for-tat strategy, for example, requires the addition of generosity or contrition to be effective in the face of even rare misperceptions (Molander 1985; Wu and Axelrod 1995).
Examining the dynamics of the model reveals how the ethnocentric strategy becomes so common and how "cheaters" are suppressed by ethnocentrics of a dif ferent color. In the early periods of a run, the scattered immigrants create regions of similar agents (Figure la). Colonies of those willing to cooperate with their own color will tend to grow faster, but over time, they face free riding by egoists who arise by mutation. Egoists who free ride cannot be suppressed by ethnocentrics of the same color and therefore tend to erode cooperative regions. Once the space is nearly full, another dynamic is added as regions with different attributes expand until they are adjacent to each other. These dynamics can be analyzed in terms of regions of contiguous agents having the same color and strategy (Figure lb). The most important aspect of regional dynamics is that an ethnocentric region will tend to expand at the expense of a region of a different color using any one of the other three strategies (Figure 2). In this way, free riding is controlled?egoists of any one color are suppressed by ethnocentric agents of different colors.
A remarkable result is that the ability to discriminate between the in-group and the out-groups can actually promote cooperation. As long as agents can distinguish their own color from other colors, even doubling the cost of cooperation sustains a cooperation level of 56 percent. However, when agents are unable to distinguish their own color from others, cooperation in the doubled-cost case falls to 14 percent. Therefore, as the cost of giving help increases, the ability to distinguish between in group and out-group members can be essential for the maintenance of cooperation in "austere" environments. In fact, the ability to distinguish between groups can be regarded as a basis for social capital within a group (Coleman 1990; Putnam 2000).
[RA Hammond, R Axelrod. The evolution of ethnocentrism. Journal of Conflict Resolution, 2006.]

Altruism via kin-selection strategies that rely on arbitrary tags with which they coevolve (pdf):

We show with an evolutionary model how contingent altruism can be sustained even when arbitrary heritable indicators of relatedness, called ‘‘tags’’, coevolve with the strategies gov- erning behavior. Discrimination based on tags is not assumed, but rather evolves endogenously in a viscous population (i.e., local reproduction and local interaction) and is selected for even when phenotypic matching is very coarse-grained. We also show how to extend Hamilton’s rule to establish the conditions under which kin recognition can support discrim- inating altruism even when coevolution causes the reliability of indicators of relatedness to vary with each individual’s evolving social environment. [. . .]
The resulting agent-based model is based on a model previously developed to study ethnocentrism in humans (Ax- elrod and Hammond 2003). The present model is not meant to be a literal representation of biological processes. Instead, our model is designed to illuminate the consequences of the fact that kin discrimination typically entails coevolution of three things: the strategies governing behavior, the reliability of the tags on which the behavior may be conditioned, and the population structure that determines who interacts with whom. [. . .]
The algebraic method above is the first published analysis of selection for kin recognition with simultaneous variation at the indicator and altruistic loci. This method helps us un- derstand the conditions under which kin recognition can sup- port discriminating altruism even when the reliability of in- dicators of kinship depends on the individual’s social envi- ronment.
The value of being able to distinguish tags can be under- stood in terms of inclusive fitness theory that takes into ac- count the degree of relatedness between two agents (Hamilton 1964; Lacy and Sherman 1983; Riolo et al. 2001). While proximity alone can be an indication of relatedness, being able to distinguish among heritable tags, as in the armpit effect (Dawkins 1982; Hauber and Sherman 2000; Hauber et al. 2000; Mateo and Johnson 2000; Isles et al. 2001), allows a still better indication of relatedness, for example among sessile cnidarians (Grosberg and Quinn 1989; Grafen 1990). The discriminatory abilities required for the armpit effect are likely to be widespread. The self-recognition required for multicellularity provides them from intimate contact, and the need to distinguish conspecifics for mating provides them more generally for animals. In both cases, a hardwired com- parison known as the green beard effect (Hamilton 1964; Dawkins 1976; Haig 1996; Grafen 1998; Keller and Ross 1998) would seriously slow evolution and make speciation almost impossible.
Viscosity is ubiquitous because few populations complete- ly mix from one generation to the next. Hamilton (1964) believed that simple viscosity was a widespread sufficient cause of fairly weak altruism, and various models have found that viscosity can indeed foster cooperation (Getty 1987; Pol- lock 1989; Nowak and May 1992; Nakamaru et al. 1997). However, this general claim is now considered doubtful. The balance between increased relatedness and increased com- petition between neighbors may tilt toward or away from cooperation (Taylor 1992; Wilson et al. 1992; West et al. 2002). Taylor and Irwin (2000) have suggested that with overlapping generations, and with altruism dispensed as ben- efits to fecundity, there is a tendency for population viscosity to support altruism. The 15.6% cooperation found in our model with one tag is on the one hand more than zero, sup- porting Taylor and Irwin, but on the other hand is rather limited. Adding observable tags shows that proximity can sustain cooperation based on contingent altruism, even if the very correlation of tags and relatedness evolves. By putting both the matching and the altruism under explicit genetic control, the model shows how altruism conditional on heritable tags can evolve despite substantial costs of cooperation. Thus, the present model, which combines viscosity, the armpit effect, and endogenous use of discrimination in a genetically explicit way, creates a very general expectation of widespread, and not necessarily weak, conditional altruism in nature.
[R Axelrod, RA Hammond, A Grafen. Altruism via kin-selection strategies that rely on arbitrary tags with which they coevolve.]

And some related work:

Recent agent-based computer simulations suggest that ethnocentrism, often thought to rely on complex social cognition and learning, may have arisen through biological evolution. From a random start, ethnocentric strategies dominate other possible strategies (selfish, traitorous, and humanitarian) based on cooperation or non-cooperation with in-group and out-group agents. Here we show that ethnocentrism eventually overcomes its closest competitor, humanitarianism, by exploiting humanitarian cooperation across group boundaries as world population saturates. Selfish and traitorous strategies are self-limiting because such agents do not cooperate with agents sharing the same genes. Traitorous strategies fare even worse than selfish ones because traitors are exploited by ethnocentrics across group boundaries in the same manner as humanitarians are, via unreciprocated cooperation. By tracking evolution across time, we find individual differences between evolving worlds in terms of early humanitarian competition with ethnocentrism, including early stages of humanitarian dominance. Our evidence indicates that such variation, in terms of differences between humanitarian and ethnocentric agents, is normally distributed and due to early, rather than later, stochastic differences in immigrant strategies.
[Max Hartshorn, Artem Kaznatcheev and Thomas Shultz. The Evolutionary Dominance of Ethnocentric Cooperation. Journal of Artificial Societies and Social Simulation 16 (3) 7]

Hamilton on inclusive fitness and social behavior in humans

In his "admittedly speculative outline of certain cultural and genetic processes in tribal evolution", Hamilton emphasizes selection at a level higher than that of the individual. From "Innate social aptitudes of man: an approach from evolutionary genetics" (text; pdf):

TRIBAL FACIES OF SOCIAL BEHAVIOR
[. . .] The other point concerns the distribution of gene frequencies. The apparent variability of colonies is expected to change rather sharply at certain critical levels of migration. These are M=.5 for the island model and M=1 for the two-dimensional stepping-stone model with close migration predominant. This means that at about the point where the colony members are related to each other like outbreds sibs it should become relatively easy for individuals to detect a fairly clear difference in appearance when comparing fellow colony members with outsiders. Actually, in the stepping-stone model the possibilities with regard to patchiness and cline-like effects are complex, but, considering simultaneously several traits which are independently inherited and at most weakly selected, the complex overlap of patterns should make possible fairly accurate separation of 'us' and 'them' at the level of colonies. We shall shortly see why natural selection might favour motivation and ability so to discriminate.

Testosterone and intergroup competition

Does Competition Really Bring Out the Worst? Testosterone, Social Distance and Inter-Male Competition Shape Parochial Altruism in Human Males

Parochial altruism, defined as increased ingroup favoritism and heightened outgroup hostility, is a widespread feature of human societies that affects altruistic cooperation and punishment behavior, particularly in intergroup conflicts. Humans tend to protect fellow group members and fight against outsiders, even at substantial costs for themselves. Testosterone modulates responses to competition and social threat, but its exact role in the context of parochial altruism remains controversial. Here, we investigated how testosterone influences altruistic punishment tendencies in the presence of an intergroup competition. Fifty male soccer fans played an ultimatum game (UG), in which they faced anonymous proposers that could either be a fan of the same soccer team (ingroup) or were fans of other teams (outgroups) that differed in the degree of social distance and enmity to the ingroup. The UG was played in two contexts with varying degrees of intergroup rivalry. Our data show that unfair offers were rejected more frequently than fair proposals and the frequency of altruistic punishment increased with increasing social distance to the outgroups. Adding an intergroup competition led to a further escalation of outgroup hostility and reduced punishment of unfair ingroup members. High testosterone levels were associated with a relatively increased ingroup favoritism and also a change towards enhanced outgroup hostility in the intergroup competition. High testosterone concentrations further predicted increased proposer generosity in interactions with the ingroup. Altogether, a significant relation between testosterone and parochial altruism could be demonstrated, but only in the presence of an intergroup competition. In human males, testosterone may promote group coherence in the face of external threat, even against the urge to selfishly maximize personal reward. In that way, our observation refutes the view that testosterone generally promotes antisocial behaviors and aggressive responses, but underlines its rather specific role in the fine-tuning of male social cognition.

Testosterone Administration Reduces Lying in Men

From the Plos ONE article:

Testosterone is known to influence brain development and reproductive physiology but also plays an important role in social behavior [4]–[9]. While most studies have investigated a potential association between testosterone and aggressive behavior, two recent studies suggest that testosterone may also increase prosocial behavior or lead to less selfish behavior in certain situations [6], [9]. We therefore investigate a link between testosterone and self-serving lying. A prominent interpretation of the existing evidence on the role of testosterone in social behavior is that the hormone enhances dominance behavior, i.e., behavior intended to gain high social status [6]–[8], [10]–[14], which in humans can be aggressive or prosocial depending on the context. Recent research suggests that pride may have evolved as an affective mechanism for motivating such status seeking behavior [15]. Pride is indirectly linked to status seeking because it is an inward directed emotion that signals high status or ego. It has been speculated that testosterone helps translate such motivation into action, for example, in acts of heroic altruism [16], [17]. Importantly, an effect of testosterone on behavior via pride should also work if behavior cannot be observed by others and an individual’s status in the eyes of the others may therefore not be directly affected. [. . .]
Our main finding is a lower incidence of self-serving lies in the testosterone group. [. . .]
While we can rule out a belief effect we cannot ultimately conclude whether our findings are driven by a direct influence of testosterone on prosocial preferences or via increased status concerns. A potential interpretation for our findings is that testosterone administration affects a concern for self-image [25], or pride [16], i.e., enhances behavior which will make a subject feel proud and leads to the avoidance of behavior considered “cheap” or dishonorable. Subjects in our testosterone group may therefore lie less. This is intriguing because pride could be an affective mechanism underlying a link between testosterone and dominance behavior. An interpretation of our findings in terms of pride is in line with anecdotal and correlational evidence indicating that testosterone plays a positive part in heroic altruism [17]. It is also in line with reports that high testosterone individuals display more disobedient behavior in prison environments where proud individuals may be less willing to follow the strict rules and comply with orders [26], [27]. Finally, a relation between pride, testosterone, and the willingness to engage in “cheap” behavior also fits the observation that the five inmates with the lowest testosterone levels in a sample of 87 female prison inmates were characterized as “sneaky” and “treacherous” by prison staff members [27]. Further experiments manipulating whether lying is an honorable action (e.g., lying for charity) or not (lying for self) are needed to clarify the role of pride in the effect of testosterone on human social behavior. An alternative interpretation of our results, which we cannot rule out, is that testosterone has a direct effect on prosocial behavior, making people more honest per se.

The press release:

The researchers compared the results from the testosterone group to those from the control group. "This showed that the test subjects with the higher testosterone levels had clearly lied less frequently than untreated test subjects," reports the economist Prof. Dr. Armin Falk, who is one of the CENS co-directors with Prof. Weber. "This result clearly contradicts the one-dimensional approach that testosterone results in anti-social behavior." He added that it is likely that the hormone increases pride and the need to develop a positive self-image. "Against this background, a few euros are obviously not a sufficient incentive to jeopardize one's feeling of self-worth," Prof. Falk reckons.

Greater policing required to enforce cooperation in "diverse" societies

A Test of Evolutionary Policing Theory with Data from Human Societies (PLoS ONE):

In social groups where relatedness among interacting individuals is low, cooperation can often only be maintained through mechanisms that repress competition among group members. Repression-of-competition mechanisms, such as policing and punishment, seem to be of particular importance in human societies, where cooperative interactions often occur among unrelated individuals. In line with this view, economic games have shown that the ability to punish defectors enforces cooperation among humans. Here, I examine a real-world example of a repression-of-competition system, the police institutions common to modern human societies. Specifically, I test evolutionary policing theory by comparing data on policing effort, per capita crime rate, and similarity (used as a proxy for genetic relatedness) among citizens across the 26 cantons of Switzerland. This comparison revealed full support for all three predictions of evolutionary policing theory. First, when controlling for policing efforts, crime rate correlated negatively with the similarity among citizens. This is in line with the prediction that high similarity results in higher levels of cooperative self-restraint (i.e. lower crime rates) because it aligns the interests of individuals. Second, policing effort correlated negatively with the similarity among citizens, supporting the prediction that more policing is required to enforce cooperation in low-similarity societies, where individuals' interests diverge most. Third, increased policing efforts were associated with reductions in crime rates, indicating that policing indeed enforces cooperation. These analyses strongly indicate that humans respond to cues of their social environment and adjust cheating and policing behaviour as predicted by evolutionary policing theory.

David Sloan Wilson on kin selection and group selection

Open Letter to Richard Dawkins: Why Are You Still In Denial About Group Selection?

I do not agree with the Nowak et al. article in every respect and will articulate some of my disagreements in subsequent posts. For the moment, I want to stress how alone you are in your statement about group selection. Your view is essentially pre-1975, a date that is notable not only for the publication of Sociobiology but also a paper by W.D. Hamilton, one of your heroes, who correctly saw the relationship between kin selection and group selection thanks to the work of George Price. Ever since, knowledgeable theoretical biologists have known that inclusive fitness theory includes the logic of multilevel selection, which means that altruism is selectively disadvantageous within kin groups and evolves only by virtue of groups with more altruists contributing more to the gene pool than groups with fewer altruists. The significance of relatedness is that it clusters the genes coding for altruistic and selfish behaviors into different groups.

See earlier post for links to replies to Nowak et al. by Dawkins and others.

Kin selection not dead

Explaining eusociality:

There's a slightly embarrassing paper out in Nature last week with E.O. Wilson on the list of authors that disparages inclusive fitness (the logic behind kin selection) and insists that (a) its explanatory power and contributions to evolutionary biology have been limited and (b) it can be ditched outright in favor of "standard natural selection theory". What is meant by this last phrase is not entirely clear, but what is clear is that the authors do not understand inclusive fitness and have completely overlooked the many ways in which it has illuminated us (sex ratio adjustment as the prime example). The authors have a section titled "Rise and fall of inclusive fitness theory", which is curious unless they are writing alt history fiction.

I am only going to comment briefly on the paper, because Jerry Coyne and Richard Dawkins have already chewed it up.

John Hawks agrees:

The weird part of the paper is the way it describes inclusive fitness as some kind of theoretical afterthought, useful only as an ad hoc explanation for eusocial insects. It contrasts the inclusive fitness concept with "standard natural selection" as if it were possible for organisms to erase the fact that they're related to each other! And the authors imply that they have fatally damaged the concept of kin selection.

It's so contrary to evolutionary theory, that I thought maybe I was missing something. But I've been spending time on another problem this week and haven't had time to follow it up.

AVPR1a and altruism

Nature news:

'Ruthlessness gene' discovered

Selfish dictators may owe their behaviour partly to their genes, according to a study that claims to have found a genetic link to ruthlessness. The study might help to explain the money-grabbing tendencies of those with a Machiavellian streak — from national dictators down to 'little Hitlers' found in workplaces the world over.

Researchers at the Hebrew University in Jerusalem found a link between a gene called AVPR1a and ruthless behaviour in an economic exercise called the 'Dictator Game'. The exercise allows players to behave selflessly, or like money-grabbing dictators such as former Zaire President Mobutu, who plundered the mineral wealth of his country to become one of the world's richest men while its citizens suffered in poverty.
[. . .]
Prosocial hormone

Ebstein and his colleagues decided to look at AVPR1a because it is known to produce receptors in the brain that detect vasopressin, a hormone involved in altruism and 'prosocial' behaviour. Studies of prairie voles have previously shown that this hormone is important for binding together these rodents' tight-knit social groups.
[. . .]
There was no connection between the participants' gender and their behaviour, the team reports. But there was a link to the length of the AVPR1a gene: people were more likely to behave selfishly the shorter their version of this gene.

It isn't clear how the length of AVPR1a affects vasopressin receptors: it is thought that rather than controlling the number of receptors, it may control where in the brain the receptors are distributed. Ebstein suggests the vasopressin receptors in the brains of people with short AVPR1a may be distributed in such a way to make them less likely to feel rewarded by the act of giving.
[. . .]
Researchers should nevertheless be careful about using the relatively blunt tool of the Dictator Game to draw conclusions about human generosity, says Nicholas Bardsley at the University of Southampton, UK, who studies such games.
[. . .]
This suggests that the apparently more altruistic players in Ebstein's game may in fact be motivated by a desire simply to engage fully with the game, perhaps just because they feel that that is what's expected of them.

If that is true, then apparently ruthless dictators may be motivated not by out-and-out greed but by a simple lack of social skills, which leaves them unable to sense what's expected of them.

The paper (pdf manuscript here):

doi:10.1111/j.1601-183X.2007.00341.x
Genes, Brain and Behavior. Volume 7 Issue 3 Page 266-275, April 2008.
Individual differences in allocation of funds in the dictator game associated with length of the arginine vasopressin 1a receptor RS3 promoter region and correlation between RS3 length and hippocampal mRNA
Knafo et al.
Human altruism is a widespread phenomenon that puzzled evolutionary biologists since Darwin. Economic games illustrate human altruism by showing that behavior deviates from economic predictions of profit maximization. A game that most plainly shows this altruistic tendency is the Dictator Game. We hypothesized that human altruistic behavior is to some extent hardwired and that a likely candidate that may contribute to individual differences in altruistic behavior is the arginine vasopressin 1a (AVPR1a) receptor that in some mammals such as the vole has a profound impact on affiliative behaviors. In the current investigation, 203 male and female university students played an online version of the Dictator Game, for real money payoffs. All subjects and their parents were genotyped for AVPR1a RS1 and RS3 promoter-region repeat polymorphisms. Parents did not participate in online game playing. As variation in the length of a repetitive element in the vole AVPR1a promoter region is associated with differences in social behavior, we examined the relationship between RS1 and RS3 repeat length (base pairs) and allocation sums. Participants with short versions (308–325 bp) of the AVPR1a RS3 repeat allocated significantly (likelihood ratio = 14.75, P = 0.001, df = 2) fewer shekels to the ‘other’ than participants with long versions (327–343 bp). We also implemented a family-based association test, UNPHASED, to confirm and validate the correlation between the AVPR1a RS3 repeat and monetary allocations in the dictator game. Dictator game allocations were significantly associated with the RS3 repeat (global P value: likelihood ratio χ2 = 11.73, df = 4, P = 0.019). The association between the AVPR1a RS3 repeat and altruism was also confirmed using two self-report scales (the Bardi–Schwartz Universalism and Benevolence Value-expressive Behavior scales). RS3 long alleles were associated with higher scores on both measures. Finally, long AVPR1a RS3 repeats were associated with higher AVPR1a human post-mortem hippocampal messenger RNA levels than short RS3 repeats (one-way analysis of variance (ANOVA): F = 15.04, P = 0.001, df = 14) suggesting a functional molecular genetic basis for the observation that participants with the long RS3 repeats allocate more money than participants with the short repeats. This is the first investigation showing that a common human polymorphism, with antecedents in lower mammals, contributes to decision making in an economic game. The finding that the same gene contributing to social bonding in lower animals also appears to operate similarly in human behavior suggests a common evolutionary mechanism.

Associations for AVPR1a with "creative dance performance" and "spirituality", eating behavior, and autism have also been claimed. Populations vary in allele frequencies at a nearby SNP, but a quick search fails to locate any data on population variation in RS3 repeat length. If you find some, post it.