I favour using inclusive fitness - in place of individual fitness - in most places where the concept is used. Individual fitness just isn't nature's maximand.
One thing this means is that kin selection gets classified as a form of genetic self-interest - rather than
being classified as being "altruism". "Reciprocal altruism" is also classified as being selfish - despite its name.
However, others argue against such definitions, saying things like this:
As Sober and Wilson (1998) note, if one insists on saying that behaviours which evolve by kin selection / donor-recipient correlation are ‘really selfish’, one ends up reserving the word ‘altruistic’ for behaviours which cannot evolve by natural selection at all.
If an altruistic behavior reduces the net fitness of the altruist and his kin, it cannot evolve.
The problem with these objections is that they are trivially wrong. Altruistic behaviours
can be favoured by natural selection - even if they are deleterious to those displaying them.
This is a simple consequence of the "extended phenotype" perspective - that traits may be coded
for in different organisms from those that exhibit them.
Viruses cause all kinds of deleterious behavioural traits in their hosts - coughing, sneezing, itching, suicide, etc.
However, these deleterious behaviours evidently do evolve via natural selection.
In the case of altruism, one of the the most likely cases involves manipulation of hosts by memes causing altruism:
Memes like to cause positive interactions between their hosts - since such friendly contact is one of the main
ways they use to spread between their hosts. So, making their hosts eager to help each other can be expected to
be the type of trait which many memes encourage. Such interactions may not necessarily be beneficial to
their hosts (altruism is, by definition, a costly act). However, such behaviour most definitely can
still evolve - via natural selection acting on memes.
I think that part of the reason we still see these kinds of explanations being offered is that understanding of memetics is
not yet very widespread.
Much enthusiasm surrounds the idea that group selection has contributed to human altruistic behaviour.
However, the altruism which group selection can create is quite limited. Altruistic behaviours can only evolve by group selection to the extent that between-group selection results in direct fitness benefits to the actor's genes - i.e. fitness benefits to the actor or their relatives.
That's quite a tall order. By contrast, the memetic explanation of altruism invokes brains being hijacked by cultural symbionts, which manipulate their hosts into behaviours that help to propagate themselves. In particular, they stimulate social behaviour that prmotes contact between their hosts.
The effect on the host's genes matters very little. The host can be sterilised, and the mechanism still works. In fact, the fewer resources the host expends on producing genetic offspring, the more resources are available for producing memetic offspring.
Memes can thus produce extreme altruism. They can produce pathological altruism. We can see - by looking at hunter gatherers - how much cooperation and altruism comes from having a hefty dose of memes. I don't mean to belittle other mechanisms too much - but human altruism towards non-kin is - overwhelmingly - the product of memes.
It's recently come to my attention that there seems to be some confusion about the role of reciprocity in human society. To illustrate, here's Peter Turchin:
Unfortunately, the reciprocal altruism breakthrough turned out to be illusory in the larger quest for the understanding of why humans are such a cooperative species. The problem is that it really works best for tiny groups of two, or very few people. Once the group becomes larger than 5–10, reciprocal altruism starts to break down, and it is certainly not the answer for lasting cooperation for any realistic group sizes, even in small-scale human societies (hundreds, or a few thousands of individuals).
...and here's Peter J. Richerson and Robert Boyd (2005) in Not By Genes Alone:
Despite its many problems, theoretical work does make one fairly clear prediction that is revevant here: reciprocity can support cooperation in small groups, but not in larger ones. [...] Theoretical work suggests that this phenomenon will limit reciprocity to quite small groups, and while no good empirical data exist, it does fit with everyday experience. [...] We eventually stop inviting friends over to dinner if they never return our invitations; we become annoyed at our spouse if she does not take her turn watching the children; and we change auto mechanics if they repeatedly overcharge for repairs. But cooperation in larger groups cannot be based on the same principle.
Both then use this "failure" of reciprocity to move on to hypotheses relating to group selection.
A prominent supporting paper for the idea that reciprocity only works in small groups appears to be a 1988 Richerson and Boyd paper - titled: "The evolution of reciprocity in sizable groups".
The conclusion of that paper says:
Reciprocity is likely to evolve only when reciprocating groups are quite small.
The paper models cooperation within large groups by repeatedly sampling n individuals from the group and using an n-person Prisoner’s dilemma. However, that just doesn’t match up with how reciprocity actually works in large groups. Most reciprocal relationships – as the very word “reciprocal” might imply – involve two parties. That is the case where everyone seems to agree that reciprocity works. However, on the level of the individual, each person has a Dunbar’s number's worth of reciprocal relationships – throughout their social network. Then the cooperative network of each individual partly overlaps with the cooperative network of every other individual, creating cooperation that permeates the whole group.
The enlarged human brain allows more relationships to be tracked - and thus a larger reciprocative network to be maintained - than is possible for most other creatures.
Of course, reciprocity doesn't explain all cooperation between members of a group - but it is highly relevant to most within-group interactions. People don't engage in very many interactions with random group members and instead spend most of their time interacting within their social circles. There, they have one-to-one relationships, can remember the names and faces of people, can track their interaction history. It is under just these kinds of circumstances that reciprocity actually works.
So, reciprocity can - and does - help to establish cooperation within huge groups, provided that there are smaller networks within those groups - which, of course, there usually are. Reciprocity applies to cooperation within governments, companies, charities and other large-scale human organisations.
Reciprocity is a big and important pro-social force for humans - but it isn't all important. There are a range of other forces that also act to establish cooperation between humans in large groups - perhaps most notably virtue signalling.
Hi! I'm Tim Tyler and this is a brief review of this book:
SuperCooperators - Altruism, Evolution, and Why We Need Each Other to Succeed by Martin Nowak and Roger Highfield.
Martin Nowak is a Harvard biologist. His book is about why humans
cooperate as much as they do - which has been a classic puzzle to
evolutionary biologists for decades.
Nowak's number one answer seems to be "game theory". Nowak has worked on this topic with others in the field - including William Hamilton and Ed Wilson. In combination with Karl Sigmund, he came up with some of the ideas behind what he calls "indirect reciprocity".
The book has a chatty style that tries to weave the stories of those involved into the science. That might make the book easier to read for some, but it also makes getting at the scientific content harder. I found this aspect of the book pretty irritating. The author also focusses a lot on their own work and does not pay sufficient heed to the work of others.
Despite the author's reported enthusiasm for mathematical models, the book is almost entirely devoid of mathematics. I don't think I found a single equation - though there were some "sigmas" lying around.
Now on to some of my more serious technical issues:
The book starts out with chapters covering the basic mechanisms that the author claims produce cooperation. These are: direct reciprocity, indirect reciprocity, spatialisation, group selection and kin selection.
Spatialisation relies on reciprocity and kin selection to operate - and so barely deserves its own category, in my opinion.
Indirect reciprocity is a bit of a dustbin category - that mixes together some very different kinds of effects. I think it is better to separate these out - into virtue signalling - which is responsible for reputations and other ways of signalling niceness and overgeneralisation.
The list fails to mention the possibility that cooperative behaviour may have been adaptive in the past - when humans lived in close-knit tribes where kin selection and reciprocity may have played a bigger role. That's a pretty important scenario, in my opinion.
The list also fails to mention manipulation. Manipulation is a key mechanism promoting cooperation. If an agent takes a hit to help another agent, they may simply be being manipulated. They could be being manipulated by the other party, one of the other party's friends or relatives, or by one of their own enemies.
The list also fails to mention the symbiosis theory of cooperation. Parasites and symbiotes may manipulate their hosts into friendly interactions - since they depend on interactions between their hosts to spread.
Lastly, the list also fails to make any mention of the role of culture in forging human cooperation. The author has some awareness of this issue - since he has a chapter on the importance of language. Also he writes:
I do not restrict the use of the term “natural selection” to genes alone. Depending on whether we talk about cells, animals, or people, reproduction can be genetic or cultural. In the former case, successful individuals leave more offspring and pass more genes on to future generations. In the latter, successful ideas, fashions, and strategies spread by imitation and learning: a fad is born.
However, the treatment of culture in the book is cursory. Nowak views culture as facilitating reciprocal relationships via gossip and helping to distribute reputations. This limited perspective is unfortunate - since cultural transmission explains why modern humans are more cooperative than beasts - and the effects of culture aren't just down to reciprocity. In fact, cultural transmission is really what brings the symbiosis theory of cooperation to life. Memes manipulate their hosts into coming into close contact with each other - in order to facilitate their own reproduction. There are also cultural versions of kin selection and group selection to consider - in which these phenomena act on related memes and groups of memes respectively.
So, Nowak's list of mechanisms of cooperation misses out a lot that is significant. This book needs complete rewrite to account for the forces that actually result in human cooperation.
Nowak became infamous recently - in a bust up over kin selection. He wrote an article with E. O. Wilson about kin selection and group selection, in which kin selection got bashed. The article was called "The evolution of eusociality" and it was published in Nature. It was poorly written and was widely ridiculed. However, the group selection controvery and the role of E. O. Wilson in it is turning out to be an interesting chapter in the history of biology - and Wilson is publishing his own book on the topic later this year. One of the reasons I decided to read SuperCooperators is to see what Nowak had to say for himself on the topic in his book.
My council for any others thinking of doing the same is: don't bother. The section in the book bashing kin selection is pretty dreadful. Nowak doesn't say anything particularly interesting or insightful in the chapter that isn't in the "eusociality" paper. Rather he reinforces the impression that he doesn't know what he is talking about. He belittles Price's equation as being "tautological" - which seems to be a particularly stupid criticism to me. The chapter on group selection isn't much better. Group selection is an interesting topic - but I don't recommend learning about it from Nowak. He mostly just talks about the group selection models he personally built - without giving enough information for anyone to actually reproduce them. That is not worth very much, in my opinion.
In the final chapter, Nowak proposes that "natural cooperation" be added to Darwin's "mutation" and "natural selection" principles. I think that this suggestion doesn't make sense. Instead: production, elimination, mutation, symbiosis, synergy, self-organisation, learning and engineering are a much better list of fundamental evolutionary principles.
In the final chapter, Nowak explains why a scientific understanding cooperation is important for building cooperative enterprises - and that mastering cooperation is an important key for humanity when facing challenges in the modern world.
That all seems to be correct - but we need much better science that what Nowak has to offer in order to properly understand why humans cooperate.
There are a few interesting bits in this book, but probably its most salient feature is the way that it misses out so much that is of vital importance to the subject it is discussing.
The latest paper from Henrich, Boyd and Richerson is called "The puzzle of monogamous marriage". It ponders the puzzle of monogamous marriage - how monogamy has spread while wealth inequality has increased.
Much of the paper is devoted to showing that monogamy is good for society-level fitness. They invoke cultural group selection to explain monogamy's spread.
Slavery seems like a suitable point of comparison. This is also widely banned - despite the fact that the richest might be expected to benefit most from it.
Wife inequality is seen as more of a moral issue than wealth inequality - and technological growth independently fuels wealth inequality.
Is the spread of spread of monogamy down to cultural group selection? I'm sceptical. It is true that in the democractic, religious and political revolutions and invasions that have spread monogamy a whole buch of memes gets supressed at once. However, describing this as being a form of group selection seems a bit controversial. A whole bunch of birds went extinct at once when mammals reached New Zealand. However, few would describe that as being a form of group selection. The invading animals wiped out the natives bacause they were fitter than them - not because of group-level effects.
Looking at large groups of memes going extinct during a major mass extinction event isn't terribly good evidence for cultural group selection, IMHO. In general, one group of organisms systematically wiping out their neighbours is just evolution as usual. Group selection - at least of the type that is controversial among biologists - is a more demanding concept than this.
The outcome shows that the monogamy meme bacame fitter as civilization progressed. If it could additional be shown that monogamy lost out to polygamy within groups, that would then qualify as evidence for group-level selection. However, the paper doesn't do that, and the idea that the polygamy meme wins within groups is probably simply false. In which case, group selection is not clearly needed as a hypothesis to explain the results.
A simple explanation for monogamy is democracy. Monogamy is deleterious for 90% of males and probably most females too. The few males it benefits may be powerful, but they are simply out-flanked by the rest of society. This explanation is simple, obvious - and it doesn't invoke group selection.
Memetic altruism is the most obvious thing to look for if looking for evidence favouring cultural group selection. At the moment, people see things that aren't explained by existing theories of altruism, and then invoke forms of group selection. However, it seems to be that this happens largely because they don't have a decent list of the known causes of human altruism. That seems to be largely because of a widespread incomplete understanding of memetics. Account properly for the existing known causes of altruism and group selection theories have a lot less work to do.
Pinker's recent book seems to be popular. It's about why human violence has recently declined. Of course, the reason why violence has declined is because of cultural evolution. Essentially:
Memes push humans into close proximity to facilitate their own reproduction - and to do this, the humans need not to bristle with hostility. So the cultural elements manipulate the humans into exhibiting low levels of hostility.
This is much the same process that has resulted in human ultrasociality - though there, since memes are (on average) beneficial, such traits are gradually getting transferred into the genome via genetic assimilation. This process is currently far from complete.
However, Pinker has - fairly recently - publicly paraded his ignorance of cultural evolution (see also his views in "How The Mind Works" and "The Darwin Debate"). Pinker has previously described some aspects of cultural evolution as "one of the domains that we shouldn't look to evolutionary biology to explain" - and he apparently endorses the idea that "the most interesting things about humans are precisely those that evolutionary theory can't explain". So: how come he is writing a book about a topic which requires explanation in terms of ideas which he doesn't seem to know very much about?
Pinker apparently endorses Robert Wright's argument in NonZero - although NonZero is full of cultural evolution and memes.
Perhaps the most surprising, and welcome, aspect of Pinker's new work is that it is implicitly a devastating nail-in-the-coffin critique of the brand of evolutionary psychology with which Pinker has identified for many years.
...and goes on to say that Pinker offers a gene-culture coevolution theory. If so, that might be the beginning of quite a turnaround!
This video has Pinker making his case:
Pinker mostly seems to just assume technological and social development, without presuming to explain how or why that development happens.
The evolution of altruism has been a hot topic for decades.
Here is my summary of the explanations for why humans are altruistic and cooperate:
Kin selection - humans cooperate with percieved kin;
Reciprocity - humans cooperate with other agents who have previously helped them;
Virtue signalling - humans are nice in order to signal to others how nice they are;
Manipulation - humans may have altruism induced in them by other humans - or by symbionts;
Overgeneralisation - "niceness" heuristics may be over-generalised;
These also have cultural equivalents - as follows:
Cultural kin selection - cultural symbionts cooperate with their percieved kin;
Cultural reciprocity - cultural symbionts are nice to other agents who have previously helped them;
Cultural manipulation - humans may be manipulated into being nice by cultural symbionts;
Virtue signalling and overgeneralisation have cultural equivalents too, although we won't discuss them separately here.
Lastly a couple of "catch-all" categories - which can be invoked to explain a few altruistic acts:
Maladaptions - being nice can be non-adaptive - a simple evolutionary mistake;
Adaptive in ancestral environment - some nice behaviours might have once been adaptive in ancestral environments;
A little further explanation is required for some of the categories:
Virtue signalling: this includes:
Courtship - humans are nice to impress prospective mates;
Reputations - humans are nice to improve their reputations;
Business - humans are nice to initiate reciprocal business relationships;
Friendships - humans are nice to initiate reciprocal business relationships;
Signalling must often be costly to be effective. Virtue signalling is sometimes classified as being a form of "indirect reciprocity".
Overgeneralisation: Some of the most common problems here are:
Overgeneralising the general strategy of being nice;
Overgeneralising niceness to kin - to include cultural kin (sometimes called "fictive kin");
Gratitude sometimes results in altruism which is wildly out of proportion, or given to other people besides the original altruist;
This section is intended to cover all cases of resource-limited cognition.
Manipulation: this is a very important category - and it is one which most writers on the topic omit.
Humans manipulate other humans for their own benefit, for the benefit of friends and relatives. Parasites manipulate humans into being nice - since many parasistes require human contact to facilitate their own reproduction. Mutualists do so too - though most are in a relatively poor position to control human behaviour.
Lastly memes manipulate humans - in cultural manipulation. They use cultural kin groups, pornography, promises, misinformation and numerous other tricks to manipulate humans into being nice. The memes may be engineered to do this (e.g. by prospective recipients), or they may do it for the same reason as parasites and mutualists do - because human contact assists their spread.
Altruism resulting from manipulation is often described as being "induced altruism".
Cultural kin selection: this is another important category. Again, most writers omit it. One exception is Balkin, J. M. (2003), who offers a fine treatment of the topic. I have a page on the topic here.
Cultural kin selection is conceptually linked to the idea of cultural tag-based cooperation. Literature on that topic starts with a 2001 paper by Riolo, Cohen and Axelrod titled "Evolution of cooperation without reciprocity" - and there have been a raft of follow-up papers which cite it. Cultural tags have advantages over genetic ones - since they can be dynamically switched around - as a defense against exploitation.
The cultural variantions on these phenomena tend to be most significantly boost cooperation between humans when the culture is expressed through human behaviour (rather than when expressed through cultural artifacts). If the culture is cooperating from inside humans, the human gets dragged along for the ride.
It is interesting to note how the areas which are commonly conceptually omitted are the ones which are to do with memetics. Through a lack of memetics, science in this interesting area is being systematicallly distorted.
Other factors are sometimes invoked to explain cooperation:
Group selection - humans are nice because nice groups do well;
Cultural group selection - humans are nice because of group selection acting on memes;
Group selection is a controversial issue. The very meaning of the term is disputed. It was originally used to mean something like "interdemic selection".
I haven't seen very much evidence to suggest that interdemic selection is a significant force for genes - or memes. However,interdemic selection of memes is more plausible than interdemic selection of humans.
There's also an alternative meaning of "group selection" - which makes the term apply to places where the Price equation indicates that there's a significant group-level component. This is the type of group selection promoted by D. S. Wilson and E. O. Wilson. It includes kin selection and reciprocal altruism. That kind of "group selection" is an important force, but it should not be mixed up with "interdemic selection". It is, in fact widely regarded as being equivalent to inclusive fitness theory. As such, it is fine, but about the only thing new about it is the proposed name.
Mesoudi and Jensen (2010) offer a four-point summary of the evidence for cultural group selection. It doesn't seem terribly impressive.
Superficially, the claim that culture-level group selection has created DNA-level social instincts supporting human ultrasociality is a strange one.
There's a much simpler and better hypothesis that explains why culture has promoted human ultrasociality that arose over a decade ago from within memetics. The idea is that memes need humans to get in contact with one another in order for them to reproduce. The hypothesis is covered on the page: Memes and the evolution of human ultrasociality.
The idea proposes straight-forward individual-level benefits to social behaviour with other humans - namely:
Ultrasocial individuals acquire more memes (and organic symbionts), and these are (on average) good.
Ultrasocial individuals get to influence others with their memes (and organic symbionts) more - spreading their own influence in the process, and gaining reputation and status credits that can be cashed in later.
This explanation complements explanations involving, virtue signalling, kin selection and reciprocal altruism.
Now it may be that these benefits don't outweigh the costs of some forms of altruism - but such expensive altruism is rare, and can be explained well by virtue signalling, over-generalisation and cognitive resource limitation.
There's very little need to invoke cultural group selection, it seems. There is little sign of phenomena that require explanations based on high-level selection. It is not clear why is the literature in the area is so full of such explanations - when there is a much simpler and more obvious hypotheses on the table.
References
Mesoudi, Alex & Jensen, K. (2010) Culture and the evolution of human sociality. In: The Oxford Handbook of Comparative Evolutionary Psychology, edited by J. Vonk & T. Shackelford. Oxford, UK: Oxford University Press.
Many enthusiasts for the idea that culture evolves also seem to favour the idea of group selection.
Ed Wilson has returned to the "group selection" camp in recent years. David Sloane Wilson promotes both cultural evolution and group selection.
Something called "cultural group selection" is promoted by Boyd, Richerson, Mesoudi, Henrich, Gintis and Nesse as being a significant force which has supposedly helped to shape human ultrasociality.
Many of these authors claim that cultural group selection is dramaticallly different from group selection in the organic realm. For example, Boyd and Richerson (2005) write:
selection between large groups of unrelated individuals is not normally an important force in organic evolution. Even very small amounts of migration are sufficient to reduce the genetic variation between groups to such a low level that group selection is not important. However, as we will explain below the same conclusion does not hold for cultural variation.
This article argues that "cultural group selection" actually closely mirrors group selection acting on parasites in organic evolution.
Enthusiasts for "cultural group selection" claim that cultural evolution acts to rapidly create between-group differences and jelps to prevent gene flow between groups. The between-group differences may also result in one group having a selective advantage. It is conjectured that these differences are sufficient to overcome the problems usually associated with group selection in the organic realm.
However, in the organic realm, evolution of pathogens also acts to rapidly create differences between populations. Pathogens can also cause between-group differences in fitness. This was seen (for example) during the European invasion of North America - where smallpox alone killed 25% of the Aztec population and between 60% and 90% of the Inca population.
One of the mechanisms proposed by Mesoudi and Jensen (2010) that would act to assist cultural group selection is that migrants adopt the social norms of their new group - acting to preserve group variation.
Migration is also a big problem for genetic group selection: in many group-living species one sex typically disperses out of the group, reducing between-group genetic differences. In humans, however, migrants often acquire the social norms of their new cultural group, maintaining between group cultural variation and consequently allowing cultural group selection to act.
However, much the same thing happens in the organic realm as well: migrants go on to contract the parasites of the groups they migrate into.
Sometimes migrants successfully introduce parasites into their new group. However that happens with culture too - migrants can carry beneficial ideas and inventions that subsequently spread like a plague through the new group.
Mesoudi and Jensen (2010) propose that the evolution of modern corporations may exhibit a form of group-level selection on human culture. However, there employees regularly drift between organisations, carrying skills and knowledge with them. NDAs and employment contracts attempt to prevent such losses, with limited success.
Corporations do represent large-scale cultural entities that compete with one another for human resources. However, flu strains also compete with one another on a large scale for access to human hosts. Just as employees of two different corporations may attend the same Masonic meetings, and the same bridge club, so hosts of different strains of flu virus may be infected weith different strains of warts virus and different strains of syphylis.
The broad equivalence between the cultural and organic realms in this area should come as no surprise for those who are already accustomed to treating culture as composed of rapidly-reproducing symbionts with "genes" which are not made out of DNA.
Another issue in this area concerns whether group selection on culture (or parasites) results in group selection on the level of the DNA genomes of their hosts. Between-group differences, sharper group boundaries and differences in fitness between groups may result in the deaths of host groups, along with the deaths of their culltures and parasites.
However, it is fairly common for invaders to spare native women. Also, it seems implausible that between-group migration rates are low enough to prevent individual-level selection swamping group selection when considering only DNA inheritance. Group selection in the human DNA-gene pool is probably a fairly minor force.
Are there differences between groups of humans with different cultures and groups of humans with different parasites which are relevant to the issue of group selection? Yes: culture acts as visible marker which acts to distinguish different groups. That may make the boundaries between groups crisper, and reduce gene flow between them. Parasites probably do that to a much reduced extent. Immigrants are less clearly marked out by their different parasites than by their different cultures - since their parasites are quite often invisible latent infections. They might hesitate to enter new groups through fear of the group's parasites, though. Similarly, groups might reject imigrants out of concern for acquiring their parasite load. However, xenophobia based on cultural cues is probably a more intense force.
Proponents cite conformity and punishment as mechanisms which stabilise groups so they act as independent units. However, such forces apply mainly within the moral realm - and not to (say) the spread of innovations. Some aspects of culture are more likely to spread between groups - and are less likely to be subjected to group-level selection forces. Spread of innovation is one of the main factors strong enough to produce significant group-level fitness differences.
These issues are probably not major difference between the organic and cultural realms as far as group selection goes. In conclusion, the "cultural group selection" enthusiasts appear to be greatly exaggerating the differences between the cultural and organic realms. Differences between the applicability of group selection to the two domians are probably mostly fairly minor. If culture is to be used to argue that group selection is an important force, much the same argument applies to parasites in the organic realm.
References
Mesoudi, Alex & Jensen, K. (2010) Culture and the evolution of human sociality. In: The Oxford Handbook of Comparative Evolutionary Psychology, edited by J. Vonk & T. Shackelford. Oxford, UK: Oxford University Press.
Richerson, Peter J. and Boyd, Robert (2005) Not by Genes Alone: How Culture Transformed Human Evolution. University of Chicago Press: Chicago, IL.
Hi! I'm Tim Tyler, and this is a video about memes and the evolution of human ultrasociality.
Humans are ultrasocial creatures. They live in large cities and and often congregate in huge numbers at social events of various kinds. Humans do not normally bristle with hostility on encountering other humans - and indeed are likely to engage in cooperative behaviour - even with strangers. Memetics offers an interesting explanation of human cooperation and ultrasociality.
The idea is that meme reproduction depends on social contact between humans. Increased levels of social contact between their hosts are good for memes since this results in more reproductive opportunities for them. Memes that promote human ultrasociality have the effect of pushing humans into close proximity with each other, so the memes can infect new hosts. All the memes in the host benefit from this - including the ultrasociality memes.
Ultrasocial humans collect more memes than less sociable humans. Since memes are - on average - beneficial, memes promoting ultrasociality can have the effect of increasing the genetic fitness of their human hosts - by allowing them to collect more memes. So, the hosts are typically eager to embrace ultrasociality-producing memes - and would eventually evolve some degree of ultrasociality anyway in meme-rich evironments. Over time the ultrasociality trait gradually begins to migrate into their germ line, via the classical process of genetic assimilation, so that learning it slowly becomes easier.
Memeplexes also tend to favour the incorporation of ultrasociality memes into them. Ultrasociality memes offer a double fitness boost to memes they have memetic linkage with. The first boost is due to being linked to the fit ultrasociality memes and the second boost due to being more likely to be spread around by the ultrasocial hosts of the ultrasocial memes. Memes in memeplexes are thus likely to welcome ultrasociality memes into the fold.
Large-scale group behaviour is a key component of many religions. In masses, a large mass of humans congregates and engages in a festival of meme exchange. Church services are regular mini-masses. Since memes are stored in fallible human memory and benefit from frequent rehearsal, the meme repetition that takes place at masses and church congregations is also beneficial to them. While such religious ceremonies may offer benefits to the humans that engage in them, they seem to be orchestrated by memes, and it is probably mostly the memes that benefit from them. Religions also promote social behaviour in another way - by actively promoting prosletysing. This essentially involves approaching strangers and attempting to spread your memes to them, and bring them into the flock. This is a particularly-blatant attempt by the memes to use host resources to further their own reproductive ends by infecting new hosts. An understanding of how memes cause humans to form masses and congregations - and to engage in prosletysing - looks as though it will form a important part of a naturalistic theory of religion.
As far as I know, links between memes and human sociality and cooperation were first proposed by Donald T. Campbell in a 1983 article titled "The two distinct routes beyond kin selection to ultrasociality". The theme was taken up by Francis Heylighen in 1992 and expanded on by him over the years. However, neither author really got the idea described here. The idea was eventually clearly spelled out and popularised by Susan Blackmore in a 1997 article titled "The Power of the Meme Meme" - and she has two whole chapters about memetic theories of altruism in her 1999 memetics book.
Recently, the idea that memetic evolution drove the evolution of human ultrasociality been the subject of much experimental work, and several books - by Herbert Gintis, Peter Richerson, Robert Boyd, Joseph Henrich and others.
While there is now a consensus that meme-gene coevolution is primarily responsible for human ultrasociality, alas, many of the academic researchers have ignored the simple and beautiful memetic hypothesis given here - and have instead adopted what appears to be a highly implausible model based on group selection. As an illustration of this neglect, in a 2000 review of why humans cooperate - by Boyd and Richerson - there is a broad review of classes of hypotheses that have been proposed to account for the phenomenon - and the memetics-based hypotheses described here doesn't even get mentioned.
The memetic explanation given here does not claim to be responsible for all prosocial behaviour. The standard evolutionary accounts of prosocial behaviour attribute it to kin selection, reciprocal altruism, virtue signalling, cooperating to perform demanding tasks and mating behaviour. Some other hypotheses also help explain human cooperation. Humans sometime manipulate other humans into cooperating. For example, this is done with the "fake" kin groups created by military uniforms and school uniforms which are used to encourage cooperation based on percieved relatedess. Also, humans may sometimes overgeneralise the moral that it pays to be nice to others - and behave in an irrationally nice manner. This effect could be magnified in the unusual modern ecosystems in which humans find themselves - where they meet large numbers of people who are not really members of their tribe. However, the memetic explanation appears to apply to most of the cases in which humans cooperate where chimpanzees do not.
The memetic explanation of human ultrasociality should be one of the triumphs of the field. At the moment, I think it is fair to say that it is not widely recognised or understood. That plainly needs to change. There is more about memes and human ultrasociality in my book on memetics, which is now available.
Lastly, here is Daniel Dennet, lecturing on the topic:
Campbell, Donald T. (1983) The two distinct routes beyond kin selection to ultrasociality: Implications for the Humanities and Social Sciences. In: The Nature of Prosocial Development: Theories and Strategies D. Bridgeman (ed.), pp. 11-39, Academic Press, New York.
Richerson, P. J. and Boyd, R. (1998) The Evolution of Human Ultra-sociality, I. Eibl-Eibesfeldt and F. K. Salter (eds.), Indoctrinability, Ideology and Warfare. New York: Berghahn Books. Pp. 71-96.
Richerson, P. J. and Boyd, R. (2005) Solving the puzzle of human cooperation. In Evolution and Culture, edited by S. Levinson and P. Jaisson. MIT Press, Cambridge MA, pp. 105-132.
Blackmore is a parapsychologist who rejects the paranormal, a skeptical investigator of near-death experiences, and a practitioner of Zen. Her explanation of the science of the meme (memetics) is rigorously Darwinian. Because she is a careful thinker (though by no means dull or conventional), the reader ends up with a good idea of what memetics explains well and what it doesn't, and with many ideas about how it can be tested - the very hallmark of an excellent science book.
Why do humans, uniquely among animals, cooperate in large numbers to advance projects for the common good? Contrary to the conventional wisdom in biology and economics, this generous and civic-minded behavior is widespread and cannot be explained simply by far-sighted self-interest or a desire to help close genealogical kin. In A Cooperative Species, Samuel Bowles and Herbert Gintis--pioneers in the new experimental and evolutionary science of human behavior--show that the central issue is not why selfish people act generously, but instead how genetic and cultural evolution has produced a species in which substantial numbers make sacrifices to uphold ethical norms and to help even total strangers.
Cooperation among humans is one of the keys to our great evolutionary success. Natalie and Joseph Henrich examine this phenomena with a unique fusion of theoretical work on the evolution of cooperation, ethnographic descriptions of social behavior, and a range of other experimental results. Their experimental and ethnographic data come from a small, insular group of middle-class Iraqi Christians called Chaldeans, living in metro Detroit, whom the Henrichs use as an example to show how kinship relations, ethnicity, and culturally transmitted traditions provide the key to explaining the evolution of cooperation over multiple generations.
Moral Sentiments and Material Interests presents an innovative synthesis of research in different disciplines to argue that cooperation stems not from the stereotypical selfish agent acting out of disguised self-interest but from the presence of 'strong reciprocators' in a social group.Presenting an overview of research in economics, anthropology, evolutionary and human biology, social psychology, and sociology, the book deals with both the theoretical foundations and the policy implications of this explanation for cooperation. Chapter authors in the remaining parts of the book discuss the behavioral ecology of cooperation in humans and nonhuman primates, modeling and testing strong reciprocity in economic scenarios, and reciprocity and social policy. The evidence for strong reciprocity in the book includes experiments using the famous Ultimatum Game (in which two players must agree on how to split a certain amount of money or they both get nothing.)
This path-breaking book addresses the nature of human sociality. By bringing together experimental and ethnographic data from fifteen different tribal societies, the contributors are able to explore the universality of human motives in economic decision-making, and the importance of social, institutional and cultural factors, in a manner that has been extremely rare in the social sciences. Its findings have far-reaching implications across the social sciences.
In Unto Others, philosopher Elliott Sober and biologist David Sloan Wilson bravely attempt to reconcile altruism, both evolutionary and psychological, with the scientific discoveries that seem to portray nature as red in tooth and claw. The first half of the book deals with the evolutionary objection to altruism. For altruistic behavior to be produced by natural selection, it must be possible for natural selection to act on groups - but conventional wisdom holds that group selection was conclusively debunked by George Williams in Adaptation and Natural Selection. Sober and Wilson nevertheless defend group selection, instructively reviewing the arguments against it and citing important work that relies on it. They then discuss group selection in human evolution, testing their conclusions against the anthropological literature.
I favour using inclusive fitness - in place of individual fitness - in most places where the concept is used. Individual fitness just isn't nature's maximand.
Much enthusiasm surrounds the idea that group selection has contributed to human altruistic behaviour.
It's recently come to my attention that there seems to be some confusion about the role of reciprocity in human society. To illustrate, here's 
The latest paper from Henrich, Boyd and Richerson is called "
The evolution of altruism has been a hot topic for decades.
Mesoudi and Jensen (2010) offer a four-point summary of the evidence for cultural group selection. It doesn't seem terribly impressive.
Posts
