Monday 23 April 2012

Extreme altruism

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.

David Owens-Hill - Pseudoscience to Social Science

I think this is a talk is titled: "Know Your Meme". Or maybe it's called: "Pseudoscience to Social Science: Reframing Memetics in Terms of Culture, Digitally-transmitted".

Though the second title sounds interesting, this talk seems pretty basic, and has a lot of material about hipsters. You have been warned!

Oh yes, the memetics doesn't really start until about six minutes in.

Friday 20 April 2012

...but is it art?

According to this internet meme video by PBS's Idea Channel, "People are creating images and sharing them with strangers for the purposes of communicating their personal experiences? That, my friends, is art. Plain and simple."

Anti-memes

Most of the proposed definitions of the term "meme" don't say anything about how good memes have to be at spreading to qualify as such - yet, popularly, memes are considered to be contagious ideas. The more contagious they are, the more appropriate the term "meme" seems.

In this spirit, Randolph Nesse has proposed the term "anti-memes" to refer to "unspeakable ideas".

He offers some examples, as follows:

  • The next time you are having a drink with an enthusiastic fan for your hometown team, say "Well, I think our team just isn't very good and didn't deserve to win."
  • Or, moving to more risky territory, when your business group is trying to deal with a savvy competitor, say, "It seems to me that their product is superior because they are smarter than we are."
  • Finally, and I cannot recommend this but it offers dramatic data, you could respond to your spouse's difficulties at work by saying, "If they are complaining about you not doing enough, it is probably because you just aren't doing your fair share."
Alas, by spreading these examples around, I seem to be negating the idea that these are true anti-memes, since they only fail to spread in one context. However, they do illustrate the basic idea.

Links

Tim Tyler: Aunger, Darwinizing Culture (review)

Transcript:

Hi! I'm Tim Tyler and this is a review of this book:

Darwinizing Culture - The Status of Memetics as a Science. Edited by Robert Aunger.

The book arose out of a Memetics Conference which was held at Kings College, Cambridge, in June 1999. It was published in the year 2000. This was before the heyday of memetics, which came a few years later. The book presents a unique snapshot of the state of memetics from that era.

There's an "Introduction" and "Conclusion" by Robert Aunger and then various other chapters - with the advocates coming first, and the critics coming last.

Susan Blackmore's chapter "The memes' eye view" updates and responds to criticism of her 1999 book The Meme Machine. It's great material - though I don't approve of Sue's emphasis on imitation.

The late David Hull's chapter is titled: "Taking memetics seriously: Memetics will be what we make it". David chastises Blackmore for her narrow, imitation-based memetics. He ponders extending memetics to cover all learning. The chapter features David wearing his "philosopher of science" hat, and taking a look at the chances for memetics. I was especially pleased to see Hull discusssing cultural kin selection. He says:

One final example of similar processes operating in biological and memetic change is kin selection.
...and then goes on to say...

In science, scientists also distinguish between kin and nonkin, but the relevant genealogy is conceptual. The issue is not who holds similar ideas but who is conceptually connected to whom. The best way to increase the likelihood that you will be a successful scientist is to work under a successful scientist.
It's good stuff.

Then we have Henry Plotkin on "Culture and psychological mechanisms". Plotkin takes a psychologist's perspective on the topic. He also disapproves of Blackmore's narrow imitation-based memetics. He discusses the definition of culture. It's a short chapter.

Then Rosaria Conte has a chapter titled: "Memes through (social) minds". This chapter is heavier going. Rosaria discusses multi-agent systems, social simulations and their links with memetics. It's a long chapter. The best bit for me was the extension of the trio of "Fidelity, Fecundity and Longevity" to include other factors - one she calls "Adjustability" - which is to do with the ability to adapt. That's an interesting idea.

Much of the rest of the book is more critical of memetics. I'll use most of the rest of this review to respond to some of these criticisms.

Kevin Laland and John Odling-Smee contributed a chapter titled "The evolution of the meme". That mostly presented their idea of niche construction - which I think is a great idea with a dubious name.

They did present one criticism of memetics. They say:

In spite of an explicit analogy between memes and viruses (Dawkins 1976), memetics as a discipline has tended to concentrate almost exclusively on ‘infectiousness’ as the factor most responsible for why memes spread. However, the success of a virus depends not only on its infectiousness, but also on the susceptibility of its hosts, and on whether the social environment promotes contact between hosts (Ewald 1994). Based on our evolutionary perspective, we suggest that the same three factors may determine the success of memes.
I'm pretty sure that this is their idea - and not the fault of memetics. Dawkins in The Selfish Gene (from 1976) described memes as varying in fidelity, fecundity and longevity. Fecundity corresponds to Laland and Odling-Smee's "infectiousness" - but that isn't the only factor that affects meme spread - Dawkins himself listed some other ones - namely fidelity and longevity

The idea that the "infectiousness" of a meme is entirely the property of the meme itself - and doesn't depend on the memetic immune system of its hosts or the frequency of interactions between them seems too daft and ridiculous to be anything other than a straw man to me. No wonder the idea is presented without being supported by any references.

Laland and Odling-Smee finish with:

This work, and numerous other studies, simply would not have been possible without the assumption that culture could be broken down into discrete units, akin to memes. There already exists a respectable, and well-established, formal theory of memetics, in the form of cultural evolutionary and gene-culture coevolutionary theory (Cavalli-Sforza and Feldman 1981; Boyd and Richerson 1985; Feldman and Laland 1996). We recommend that meme enthusiasts exploit it.

That seems fair enough. However, that work has some hangovers associated with it that memetics could well do without - but sure the memetics folk should join forces with the academics rather than squabbling too much with them. The academics need to cut out their sniping at memes too, though!

A sympathetic interpretation of memetics is not particularly difficult to find. If people are incapable of finding such an interpretation, then they should consider trying harder - or working in some other field.

The next chapter is titled: "Memes: Universal acid or a better mousetrap?" by Robert Boyd and Peter Richerson.

The "universal acid" of the title is from Dennett's 1995 book. To explain their title, they conclude "Memes are not a universal acid, but population thinking is a better mousetrap."

Dennett originally said it was Darwinism - not memes - that was the "universal acid". It isn't clear why Boyd and Richerson have substuted the term "memes" into this thesis before criticising it.

Darwinism as a "universal acid" that eats into everything is a bit of a marketing idea - in my opinion. By contrast, population thinking is all very well - but it doesn't really play the same marketing role.

In the chapter, Boyd and Richerson summarise their own ideas about how the organic and cultural realms coevolve. This material is good. However, then they lay into memes. Their critique strikes me as being incompetent. They say:

In The Extended Phenotype, Richard Dawkins (1982) argues that the cumulative evolution of complex adaptations requires what he calls replicators, things in the physical world that produce copies of themselves, and have the following three additional properties:
  • Fidelity. The copying must be sufficiently accurate that even after a long chain of copies the replicator remains almost unchanged.
  • Fecundity. At least some varieties of the replicator must be capable of generating more than one copy of themselves.
  • Longevity. Replicators must survive long enough to affect their own rate of replication.
I don't think Dawkins said that. Nowhere in the The Extended Phenotype does Dawkins make that argument. Instead he says:

This, then, is our candidate replicator. But a candidate should be regarded as an actual replicator only if it possesses some minimum degree of longevity/fecundity/fidelity (there may be trade-offs among the three).
At the time, Boyd and Richerson avoided easy refutation by failing to provide a very specific reference for what they claimed Dawkins said. Nobody had the patience to trawl through the whole of The Extended Phenotype to verify that this argument was not included. However, now I think that what they wrote can be identified as being not something that Dawkins actually claimed or wrote.

The next chapter is by Dan Sperber. It's called "An objection to the memetic approach to culture". Sperber has several fancy critiques of memes. He concludes by saying:

Memeticists have to give empirical evidence to support the claim that, in the micro-processes of cultural transmission, elements of culture inherit all or nearly all their relevant properties from other elements of culture that they replicate
However it isn't clear to me why he thinks that this is a claim of memetics. Both organic and cultural copying can have practically any degree of fidelity - if exposed to mutagens. It all just seems like a ridiculous straw man to me.

Sperber asks:

If, as I believe, this is not even remotely the case, what remains of the memetic programme?
The answer is, of course: most of Darwinism - namely: population memetics, symbiosis, epidemiology, parasitism, mutualism, immunity, recombination, kin selection, kin competition and group selection - among other things.

Next is Adam Kuper's chapter: "If memes are the answer, what is the question?".

Adam Kuper's chapter is not great. To me, he comes across as a pissed-off anthropologist. He concludes with some criticisms:

I do not believe that memes help us. To begin with, the analogy between memes and genes is fanciful and flawed.
That criticism seems pretty vague. The idea is more that both "memes" and "genes" represent pieces of heritible information that participate in adaptive Darwinian evolution - not that there is some sort of "analogy" between them.

Adam continues:

Second, if memes are really what we would normally call ideas (and, perhaps, techniques), then it is surely evident that ideas and techniques cannot be treated as isolated, independent traits.
Uh huh? So can genes be treated as "isolated, independent traits"? I would say that genes interact during development. So, why expect to treat memes as "isolated, independent traits" if genes do not represent "isolated, independent traits"? It appears that this isn't so much a criticism as the author's own personal muddle.

Adam then says:

Third, ideas and innovations are transmitted and transmuted in ways that are very different from the transmission of genes.
It's true that some memes are transmitted through the air in the form of light rays or vibrations, while modern genes are mostly confined to nucleic acids - but so what? Darwinism just talks about inheritance, without going into implementation details too much. The details of how heritable information is transmitted and transmuted is all part of life's rich tapestry - not some sort of objection to applying Darwinian principles in the first place.

I think Adam needs to get with the program.

Lastly there's Maurice Bloch's chapter "A well-disposed social anthropologist's problem with memes".

Maurice Bloch identifies much of memetics as basic anthropology. Then he goes on to offer some criticisms. He doesn't think culture can be "atomised". He writes:

Is the practice of finishing the main rounds of rituals during the rainy season because the ancestors have so ordained and because the harvest can only take place when the crops are dry, is it a part of the memeplex about the weather, or the religion memeplex or the naive physics memeplex, or the social memeplex? Or is it that all these things link up into one gigantic memeplex? The answer to these questions can only be totally arbitrary. In reality, culture simply does not normally divide up into naturally discernible bits.
There are several issues here. One is whether you can break culture up into discrete bits. What can be divided up into discrete bits is cultural information. Information can be divided up into discrete bits - as can be clearly seen by the way so much of it it has migrated onto the discrete medium of the internet. Hopefully now, the internet clearly illustrates how cultural information can be divided up into discrete bits whose frequencies can be measured.

Then there's the issue of of whether there are "natural break lines" in cultural information - like there are on bars of chocolate - which make it more likely to divite at certain points. Natural break points can often be identified by the frequency at which actual breaks take place during transmission processes. So, for example, quotations often start with a capital letter and end with a full stop. Music, movies, art and computer programs also have natural break points. Culture does normally divide up into naturally discernible "bits". However, I don't think it always does that. There are probably even pieces of culture that have a roughly equal chance of being divided at any point.

However, the whole issue of natural break points strikes me as being a bit of a red herring. Evolution is based on heredity - and we have a science of heredity - namely: genetics. Heredity is not dependant on heritable information having natural break points. So, I see no reason why the science of cultural heredity - namely memetics - should insist on there being natural break points either. For example, you don't need natural break points to be able to perform meme frequency analysis. There the experimenter decides what sequences they are interested in looking at.

In summary, culture is full of natural break points. There may be some areas where they don't exist, but: so what? If there were no natural break points, and cultural transmission processes broke heritable information up entirely at random, memetics would be OK with that situation, most of its models would be unchanged, and the concept of a "meme" would still be a useful one.

Bloch also raises the issue that memes can overlap. However genes can overlap too. I don't see this as being a big deal.

Bloch then turns to what he calls "cultural consistency" - saying:

the transmission of culture is not a matter of passing on ‘bits of culture’ as though they were a rugby ball being thrown from player to player. Nothing is passed on; rather, a communication link is established which then requires an act of re-creation on the part of the receiver. This means that, even if we grant that what was communicated was a distinct unit at the time of communication, the recreation it stimulates transforms totally this original stimulus and integrates it into a different mental universe so that it loses its identity and specificity. In sum, the culture of an individual, or of a group, is not a collection of bits, traits, or memes, acquired from here and there, any more than a squirrel is a collection of hazelnuts.
I think this is all a misunderstanding. If memes are pieces of cultural information, then cultural information can be divided into memes - just as a matter of definition. Bloch emphasises that cultural information is "digested". Certainly some information is commonly lost during the process of transmission - but we can see that some information is not lost during transmission - the parts that contribute to cumulative cultural evolution. Those bits are more like the squirrel's genes than the squirrel's diet - since they are preserved intact down the generations. Bloch exaggerates the impact of the "digestion" process. Empirically, assimilation of culture does leave some things largely intact from one generation to the next.

Bloch says that culture:

is not a library of propositions or memes. This type of argument is principally intended as a criticism of American cultural anthropology, which (as we saw) was itself a criticism of diffusionism. But clearly it also applies to the simple diffusionist idea that culture is made up of ‘bits of information’ that spread unproblematically by ‘transmission’, where transmission is understood as a unitary type of phenomenon. British anthropologists, including myself, would argue that knowledge is extremely complex, of many different kinds, and impossible to locate, as though it were of a single type.
Information can represent complex structures of different kinds. Memes are just bits of cultural information - so have no problem representing complex information of many different kinds. As for knowledge being "impossible to locate", that reckons without the fMRI machines of the neuromarketers. They put people into scanners and then examine how their brains respond to meme exposure. The idea that memes are "impossible to locate" is one of the many criticisms of memetics that progress is gradually pushing into the dustbin of history.

Lastly one of my favourie bits from Bloch:

Of course, memeticists will want to argue that they are saying more than the diffusionists ever did and cannot therefore be dismissed in the same way. They will bring up the originality of thinking of the evolution of culture from ‘the memes’ point of view’. And, of course, they are right, because if they had been able to argue that there were such things as memes, this would have been a fascinating new perspective on human history. The point is, however, that they have not succeeded in arguing convincingly — any more than the diffusionists had before them when talking of ‘traits’ — that there are such things in the world as memes. And so, talk of invasion by the ‘body snatchers’, to use Dennett’s delightful phrase, is an idea as intriguing, as frightening and as likely as invasion by little green men from Mars.
In this passage, Bloch adopts the position of a "trait denialist" - which strikes me as a bizarre position. Of course there are cultural traits.

Bloch started off the chapter by emphasizing the similarities between memetics and conventional anthropology. However, in this passage he agrees that memetics is radical and new. If culture really is a type of symbiotic relationship with entities with inheritance not based on DNA, then that's a big deal for the social sciences, for evolutionary biology and for biology.

These days, a number of leading scientists in the field support the symbiosis perspective. Fopr example, we have Peter Richerson saying:

I think it is near to undeniable that cultural variants are sometimes selected to become selfish pathogens along the lines that Dawkins suggested. Since some cultural variants can spread rapidly among people, as in the case of fads, they rather resemble the life cycle of a viral or bacterial pathogen.
Viral videos and viral marketing are not just a way of speaking - these types of phenomenon demand models based on symbiology. So, in this passage, Bloch is wrong, but he is eloquently wrong, clearly expressing the influence of memetics on the old paradigm which it displaces.

I haven't commented on Robert Aunger's "Introduction" or "Conclusion". I don't much like those parts of the book, so I'll just keep quiet about them.

That's enough review for now. The book provides a stimulating snapshot of the state of memetics from the year 1999. I recommend it to anyone interested in the history and development of the field.

Enjoy,

Thursday 19 April 2012

Cultural traits - the meme's new clothes?

I read this paper recently:

  • Mesoudi, Alex, O'Brien MJ, Lyman RL, VanPool TL. (2010) Cultural traits as units of analysis.

    Heres the start of the abstract:

    Cultural traits have long been used in anthropology as units of transmission that ostensibly reflect behavioural characteristics of the individuals or groups exhibiting the traits. After they are transmitted, cultural traits serve as units of replication in that they can be modified as part of an individual's cultural repertoire through processes such as recombination, loss or partial alteration within an individual's mind. Cultural traits are analogous to genes in that organisms replicate them, but they are also replicators in their own right. No one has ever seen a unit of transmission, either behavioural or genetic, although we can observe the effects of transmission.
    "Cultural traits are analogous to genes"?

    That muddles together the phenotype and genotype!

    A cake isn't analogous to a gene, since it is the recipe that makes it that is normally copied from.

    It's memes that are most like genes, not the traits that they code for.

    Traits can sometimes behave a little like genes if there's only a trivial developmental process involved in their production. If developmental processes become more complex, traits become a lot less like genes and a lot more like bodies.

    I'm pretty sure that - if more people adopted the memetics terminology, we could avoid this kind of muddle.

  • Wednesday 18 April 2012

    Tim Tyler: Dugatkin, The Altruism Equation (review)

    Transcript:

    Hi! I'm Tim Tyler and this is a brief review of this book:

    The Altruism Equation: Seven Scientists Search for the Origins of Goodness by Lee Alan Dugatkin.

    The book has a fairly self-explanatory title. The Altruism Equation of the title is Hamilton's rule - and there are seven scientists on the cover - namely Charles Darwin, Warder Clyde Allee, T.H. Huxley, William Hamilton, Petr Kropotkin, George Price and J.B.S. Haldane.

    The first six chapters are about these seven fellows - with the material on Huxley and Kropotkin being combined into one chapter.

    Then there's three more chapters, one about the popularisation of science relating to altruism by Dawkins, Ed Wilson and others, one on extensions of Hamilton's ideas by Emlen, Sherman and Reeve, and then the last chapter is on Robert Axelrod and his work with Bill Hamilton.

    The book is very readable and well written. However, the readability stems partly from the book's use of personal narratives about the scientists involved. Personally, I really wanted less biography and more science. I ideally want a firehose presentation of the ideas involved - and this book isn't like that - there's quite a lot of history and biography in it.

    I read it because of my own interest in altruism and kin selection. I knew from the author's previous book on imitation that he knew a few things about memes. I was interested to see how he linked memes and altruism - and memes and kin selection.

    However, the book isn't a general book about altruism. It's really a book about the history associated with Hamilton's solution to the altruism issue involving kin selection. Though it discusses subsequent extensions of Hamilton's ideas, the idea that kin selection and inclusive fitness theory might apply to memes as well as genes receives no coverage. Nor is there any coverage of the large effect of culture on altruistic behaviour. So: many of my hopes while reading the book were rather disappointed.

    I learned quite a few bits of history from the book. I already knew most of the material about Hamilton and Price, but I hadn't even heard of Warder Clyde Allee before, and much of the unfamiliar material was interesting - it even made me expand my own thoughts about the reasons why organisms clump together.

    I felt as though the book had a bit of an identity crisis. It seemed as though it was a book on the general topic of altruism that had got scaled back part way through the project, so it only covered the material up to the 1970s. It wasn't really all about kin selection - since it had a bunch of material about Axelrod, tit-for-tat and reciprocity - but then it just stopped. Since the book was written in 2006 quite a bit has happened since the 1980s - but most of that isn't covered. I was left wondering whether there would ever be coverage of topics such as reputations, manipulation, tag-based cooperation and the impact of culture in a second volume.

    Anyway, despite the slight identity crisis, this is a fine and very readable book on the topic of altruism - and especially kin altruism.

    Enjoy,

    Know Your Meme interviews Susan Blackmore

    Here's the link: http://knowyourmeme.com/blog/interviews/qa-with-susan-blackmore-author-of-the-meme-machine

    Susan emphasizes her differences from Ray Kurzweil, saying Kurzweil’s version of "the singularity" is: "unimportant in my opinion" - and describes the state of memetics as a science as "pathetic".

    Tuesday 17 April 2012

    Peter Richerson - cultural evolution video from Darwin 2009

    The title is: Not by genes alone: Darwinian methods for the study of culltural evolution.

    Expert Peter Richerson goes over the history and development of cultural evolution. Part of "Darwin 2009" at Stony Brook University - and probably part of the Darwin 200th & 150th celebrations.

    It's a nice introduction, but, inevitably, I have a feq quibbles:

    • Peter compares variation in human genetic information with variation in human memetic information, and concludes that the variance in the memes is much greater. That's all very well, but it isn't really a fair comparison. Memes are cultural symbionts - and so one should compare them with organic symbionts. Variation in the combinations of persistent viral, bacterial and fungal symbionts is pretty large in humans.

    • Peter brings up the issue of inheritance of cultural acquired traits, but soon says that might not be such a big difference after all, though according to him we'll have to wait and see about that. The situation is that dogs pass on fleas they acquired during their lifespan to their offspring - much as humans pass on ideas they acquired during their lifespan to their offspring. Both the fleas and the ideas can mutate inside their hosts - and those changes are passed on as well. The organic and cultural realms are pretty similar in these regards.

    • Peter says that you can get memes from multiple sources - not just your parents. However, this isn't really much of a difference from the organic realm either, since you can get parasites from your offspring, peers, aunts and uncles as well - not just your parents.

    • Peter says that culture exhibits "biased transmission" - where we choose what memes we acquire. He says we are smart shoopers in the space of ideas - and are not "passive recipients, the way we are of our genes". However, humans are not passive recipients of the genes of organic symbiotes - any more that they are of the memes of cultural symbionts. For example, if you want to avoid a sexually-transmitted diseases, you can abstain, or use barrier contraceptives. The "passive recipient" model of genetic transmission is simply mistaken.

    There's a pattern to these issues. They all apparently involve a failure to fully appreciate the idea of symbiosis and apply it to the cultural realm. Peter Richerson does know about symbiosis, and has proved it in his writings by comparing cultural entities to sumbionts, viruses and bacteria. However, for some reason, the implications don't always seem to filter through.

    Wednesday 11 April 2012

    Artistic impressions of the "meme" meme

    I've come across a number of visualisations of computer viruses - perhaps most notably Weird Al's Virus Alert video. However, I haven't seen too many artistic interpretations of the "meme" meme.

    Light-bulbs are one way of doing it - as seen on the cover of my memetics book or in Pat Linse's now well-known illustration for Susan Blackmore's The Power of the Meme Meme article.

    Another approach I came across recently was in a paper titled "Memes and Fitness Landscapes". It is shown to the right. I tracked down the original. It is an illustration by Adam McCauley created for the article The Meme Hunter - by Andrew Brown.

    Somehow the hairy legs and red gloves/boots remind me of a housefly with dirty feet.

    I rather like - but meme critics will probably hate - this kind of "agentification" of the "meme" meme.

    Part of my interest in the theme is as possible inspiration for the cover of my proposed "memes" book.

    Consilience Conference

    It's listed on the "conferences" page, but the Consilience Conference is coming up. It is subtitled: Evolution in Biology, the Human Sciences and the Humanities.

    It will be held at the University of Missouri, St. Louis and will be hosted by the College of Arts and Sciences. It will take place April 26-28 at the J.C. Penney Building/Conference Center on UMSL’s North Campus.

    Here's the list of invited speakers.

    Frans de Waal: Moral behavior in animals

    The video offers some beautiful footage of animal cooperation in chimps and elephants near the start of the talk.

    This video isn't specifically to do with memetics - but memes underlie much moral behaviour in humans - so we need to understand which behaviours are caused by memes and which are not. Animal studies can help with that.

    Memes and speciation

    We know that there are many cases in which symbiosis causes speciation. Food symbionts drag species into different habitats. Some symbionts can result in cytoplasmic incompatability - and result in speciation. There's a book about the topic: Symbiosis as a Source of Evolutionary Innovation: Speciation and Morphogenesis - edited by Lynn Margulis and Rene Fester.

    Memes

    What about cultural symbionts? Numerous people have speculated that different cultural traditions historically lead to sharp divisions between human populations - though of course these days, culture appears to be having the opposite effect - of uniting the whole planet. One issue I address in my memetics book is whether the historical divisions could have been deep enough to result in reproductive isolation and speciation. We can see a number of what appear to be speciation events among our ancestors, though the sort of isolation that produced them is not always clear. Of course there's one particularly obvious speciation event - the one that divided us from chimps. Could that have been caused by a difference in cultural traditions?

    It's long been speculated that bird song is a possible cultural mechanism for speciation.

    A recent paper about speciation in killer whales proposes that learned cultural differences between ecologically divergent killer whale populations have resulted in sufficient reproductive isolation even in sympatry to lead to incipient speciation.

    These kinds of thing promote the link between cultural symbionts and speciation. If sufficient evidence of cultural symbionts causing speciation arises from the study of other species, we are going to have to seriously consider the possibility that our ancestors were so divided by their memes that their populations became permanently divided.

    Rafts

    Island isolation represents one of the best-known speciation mechanisms. It is known that some species colonise islands using natural rafts as a form of based on oceanic dispersal. Interestingly, the ability to build rafts is largely a culturally-transmitted trait among humans. Rafting could easily have promoted geographic isolation on islands among our ancestors. Human use of rafts dates back at least 100,000 years. There's evidence that Homo Erectus migrated through the Indonesian archipelago using bamboo rafts. Many other primates have managed to hop around the planet on natural rafts long before that. Memes could have isolated some of our ancestors in more than one way.

    Thursday 5 April 2012

    The role of reciprocity

    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.

    Wednesday 4 April 2012

    Cultural epidemiology criticised

    A recent article in The Economist criticises approaches to cultural evolution based on epidemiology.

    The article is called: Social contagion - Conflicting ideas The article boils down to saying that disease organisms are bad, and that people want to avoid them - whereas many ideas are good - so people want to acquire them. On that basis it apparently advocates ditching models based on epidemiology.

    The article concludes with:

    But it suggests that ideas are sufficiently different from diseases that it might not be wise naively to apply models designed for one to probe the other. High time, then, for social psychologists to stop piggybacking on epidemiologists and work harder on their own models.

    My assessment is that we need generalised epidemiology - or infodemiology - that deals with both deleterious and beneficial interactions with cultural symbionts. A generalised epidemiology is needed in both the organic and cultural realms - since both feature parasitism and mutualism.

    The article's suggestion - that we should ditch epidemiological models and start again from scratch is misguided. It violates the basic principle of building on what you already have. Switching from parasitism to mutualism in basic models of contagion is just a case of switching a sign around. It is true that adaptations for avoiding symbiotes can look a bit different from adaptations for acquiring them - but that does not entail discarding all our existing models, terminology and framework. We do have some three decades of work in cultural evolution built on epidemiological foundations. Existing models don't make the half-baked predictions that author claims arise from an epidemiological perspective.

    Copverage in Physorg puts a similar spin on the paper - saying:

    Now however, researchers from Cornell University have shown that users adopting Facebook, tend to do so more predictably when receiving invitations from multiple sources, rather than a lot of requests from members of the same group, which implies that Facebook and its growth, does not actually compare with biological contagion at all.
    The paper is this one: Structural diversity in social contagion by Johan Ugander, Lars Backstrom, Cameron Marlow, and Jon Kleinberg.

    It has thirty one references, practicallly none of which are to the primary literature on cultural evolution. Three cites support their assertion that "traditional" models predict that ideas necessarily spread according to exposure to them - rather than to the extent that recipients want to be exposed to them.

    Of course, the actual literature on cultural evolution has long been aware that contagiousness of a cultural entity depends on the properties of the entity, the properties of its hosts, and the structure of the host population (e.g. see Laland and Odling-Smee, 2000) - and it has long recognised both cultural parasitism and mutualism (e.g. see chapters 4 and 5 of Boyd and Richerson, 2005).

    Tuesday 3 April 2012

    Yochai Benkler - resources

    Yochai Benkler is interested in cooperation - particularly cooperation among humans. He is interested in net-based collaborative projects - like Wikipedia and Linux.

    Videos


    Yochai Benkler: Open-source economics


    The Penguin and The Leviathan: The Science and Practice of Cooperation

    Talks about cultural evolution 31 minutes in.


    Book Talk: Yochai Benkler on How Cooperation Triumphs over Self-Interest


    Yochai Benkler: After Selfishness - Wikipedia 1, Hobbes 0 at Half Time

    Links

    His 2011 book The Penguin and the Leviathan: How Cooperation Triumphs over Self-Interest.

    His home page.

    SFI video: The Penguin and The Leviathan: The Science and Practice of Cooperation.

    Monday 2 April 2012

    Memetics quotations

    I've put together a page of memetics quotations.

    Suggestions are welcome by mail or in the comments here.