Friday, 30 December 2011

Why humans cooperate

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.



Stats on memetics vs cultural evolution

I thought it would be interesting to attempt to quantify how memetics and cultural evolution are doing on the internet, relative to each other:

One methodology is to apply Google search statistics to their terminology:

Alas, most of their terms typically don't have enough volume to allow the use of Google Insights for Search. However I can do this:

...and this:

In other cases, I'll have to use static figures.

MemeticsCountCultural evolutionCount
"memetic drift"9,230"cultural drift"53,500
"meme"56,900,000"cultural variant"10,600
"memetics"756,000"cultural evolution"1,020,000

Of course, science is more than just a populatity contest - and there are about a million other ways in which this methodology is limited.

Thursday, 29 December 2011

Replicator rot

It does appear that some people have become confused about the role of high-fidelity copying in evolutionary processes - much as Henrich and Boyd (2002) claim.

Hull (1988) apparently based his theory of evolution on replicators, which he defined as follows:

replicator: an entity that passes on its structure largely intact in successive generations
The "largely intact" is problematical - cumulative adaptive evolution doesn't depend on high-fidelity transmission of structure - since low-fidelity transmission can be compensated for by error correction.

Let's call this mistake "replicator rot".

Aunger says this on the topic:

Any evolutionary process, including the cultural kind, needs only to exhibit features that correlate from one generation to the next. This quality is what biologists call heredity. Replication is a more precise claim about how evolution works — it suggests that a special kind of agent causes the recurrence of cultural features: a replicator. Some evolutionary approaches — competitors to memetics, such as sociobiology and evolutionary psychology — invoke only genetic heredity in their explanation of culture. I disagree. Socially transmitted information is central to the nature of culture. But when it is transmitted, is it replicated? That’s the crucial question.
He goes on to conclude that memes are replicators.

Dennett explains the basic evolutionary algorithm as being based on:

heredity or replication: the elements have the capability to create copies or replicas of themselves.
I think Dennett saves himself from replicator rot by including the terms "heredity" and "copies" - but it's a close call.

Blackmore and Dawkins mostly avoid the worst of the replicator rot as well - but they do so at the expense of giving the word "replicator" a counter-intuitive technical definition which avoids any mention of high-fidelity copying - with Dawkins (1982) saying:

I define a replicator as anything in the universe of which copies are made.
...and Blackmore (1999, p.5) saying:
a replicator is anything of which copies are made
Academic critics - such as Henrich and McElreath (2003) - typically finger Dawkins, Dennett and Blackmore - but their supporting evidence is usually inaccurate or vague.

Sue has said: "by definition, the information people copy is a replicator" and Dawkins has said: "Anything that is imitated is a form of replication". It seems clear that they don't intend any "high-fidelity copying" implications of the term "replicator" - and their explicit definitions of the term "replicator" confirm that this is indeed the case.

Dawkins did publicly succumb to replicator rot later on. In 2005's The God Delusion, page 191:

In its most general form, natural selection must choose between alternative replicators. A replicator is a piece of coded information that makes exact copies of itself, along with occasional inexact copies or 'mutations'.
This is simply wrong. Natural selection can choose between any items, whether they are frequently copied exactly or not.

In 2013, Dawkins offered:

Anything transmitted with high fidelity from brain to brain by imitation is a meme.
This is true - but it suggests that computer-based transmission doesn't count, and that high-fidelity copying is required. These both seem like highly dubious ideas.



The incorporation of individual learning into memetics appears to precipitate a crisis. Individual learning and social learning are very similar, interact deeply and coevolve. Placing a dividing line between individual and social learning is pretty unnatural and difficult - because of the scale of the interactions between these two areas.

What makes more sense scientifically is a unified theory of idea and memory evolution - which handles how ideas and memories evolve both within minds and between minds.

I go into this issue in previous posts:

In the context of the existing memetics paradigm, there are various ways of dealing with this:

  • Enlarge the definition of a meme to include individual learning;
  • Enlarge the definition of culture to include individual learning;
  • Create new units to deal with all learned information.
  • Do nothing - try and muddle through with the existing concepts.
I discussed the possibility of enlarging the definition of culture in The case for private culture.

This post looks at the possibility of creating new units to deal with learned information.

My proposal is "lemes" - an abbreviation for "learned genes". Here's a diagram showing three possible units:

Where do memes fit into this diagrem? In two possible ways. The first is conventional, the second is radical.

New terminology: Lemes

Meme terminology promoted
The advantage of using "lemes" is that it doesn't involve the confusing redefinition of any existing common terms.

The problem with the term "leme" is that it seems relatively unlikely to get anywhere. Scientists might benefit from the three separate names for units of learned information - but most people are only going to bother with one term - and the term "meme" has pretty-much already won the battle for that role.

If "lemes" failed to take off, the problem would remain, and the solution would have been pretty ineffective.

I think the umbrella category that covers all learning is the most important, and that it should probably get the best term - which today appears to be "meme". So, I don't think the idea of "lemes" described on this page would be very practical to implement.

While we are entertaining the idea of expanding memetics to include all learning, perhaps we should consider the possibility of expanding it further - to include the evolution of the brain.

Not all evolutionary changes in the brain are to do with learning - there are also changes due to developmental processes, for example.

I think this type of expansion of the idea would probably be taking things too far, though.

Wednesday, 28 December 2011

Repurposing epidemiology

Memetics is deeply based on the science of symbiosis. However, sometimes the study of symbiosis seems to be in almost as much of a muddle as the evolution of culture.

I think one of the more obvious proposals for fixing its terminology involves the term "epidemiology".

Epidemiology is the study of health-events, health-characteristics or health-determinant patterns in a population.

The etymology of the word says it means, roughly speaking: "what is on the people".

Epidemic is worse - that says epidemics are concerned with disease spread.

At the moment, the word occupies a position which could potentially be useful to the science of symbiosis. What the science of symbiosis really needs is a term to refer to the spread of symbionts through a population of hosts.

However, epidemiology today seems to be all about health. Health varies due to host genes and inorganic environmental factors as well as being affected by symbionts.

At the moment, epidemiological terminology is used ubiquitously to describe symbiosis. However it is pretty bad at dealing with mutualisms. Students of symbiosis really need to decide on their terminology. The most obvious options are:

  • Hijack epidemiology and attempt to repurpose it;
  • Develop a "generalised epidemiology" variant that covers any trait - not just health;
  • Develop a "symbiotic epidemiology" variant;
  • Deploy some entirely new terminology to describe the spread of symbionts;

I think there's a good case to be made for the first option. The second option has some merits too. I expect that the fourth option is not going anywhere.

The "rationale" for the first option is: mutualist symbionts actually have a positive effect on health. Exactly neutral symbionts are too rare to be worth mentioning. As for the fact that health varies due to host genes and inorganic environmental factors: that is acceptable.

This is pretty-much how I treated epidemiology and its associated concepts in my "Memetics" book.

I think the etymology is supportive of widespread deployment in the context of symbiosis. An alternative to repurposing epidemiology would be to develop a science of symbiology - with its own terminology. This would deal with the spread of symbionts - but not inorganic environmental factors such as chemical spills or nuclear fall-out. However, symbiology is currently underdeveloped and doesn't yet have good terminology in this area.

Perhaps in time, "epidemics" and "epidemiology" will lose their explicitly medical associations as well.

The terms "pandemic" and "plague" should also probably be taken away from medicine and repurposed for the greater scientific good.

Update: see the Generalised epidemiology post for more details.

Criticisms of memetics

My big list of criticisms of memetics is now available. Please feel free to check it out.

Thursday, 22 December 2011

Tim Tyler: Sense and Nonsense (review)


Hi! I'm Tim Tyler and this is a video review of Sense and Nonsense by Laland and Brown.

Sense and Nonsense is a great book. It covers a range of evolutionary approaches to human behaviour. The key concepts of each approach are treated in turn in separate chapters and then the authors describe case studies and then offer a critical evaluation for each one.

The approaches considered are: sociobiology, human behavioural ecology, evolutionary psychology, memetics and gene-culture coevolution.

There's also an introductory chapter, a chapter covering the history of the field prior to 1975 and a final chapter that wraps up.

I read the last three chapters first. These are the ones on memetics, gene-culture coevolution and the last chapter on "comparing and integrating approaches". I did this because Memetics and gene-culture coevolution are really the only remaining attempts at a proper study of human evolution, and that matches my own particular interests.

The authors are mostly in the "gene-culture coevolution" camp. They seem to be mostly looking at the other approaches to see where they went wrong. Their descriptions of the other approaches are pretty fair, but they do go out of their way sometimes to make then look stupid.

Despite this, their coverage of memetics is mostly accurate, sympathetic and good. However, the authors do say:

Perhaps because of the need to demonstrate that culture is a genuine evolutionary process in its own right and cannot be reduced to a mere product of biological evolution, so far meme enthusiasts have concentrated almost exclusively on the characteristics that make memes infectious. 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. The same three factors may also determine the success of memes (Laland and Odling-Smee, 2000). Were memeticists to accept that evolved genetic predispositions may influence meme adoption, leaving human beings particularly susceptible to acquiring memes that increase their reproductive success, they would converge on the ideological position of advocates of gene–culture coevolution.
This seems strange to me. I checked with Blackmore's meme book - published three years before "Sense and Nonsense" - and she has a section about how meme transmission depends on both properties of the memes and properties of their hosts on page 15.

Aaron Lynch's 1996 book talks about "cognitive immune reactions" against memes, the idea of a "memetic immune mechanism".

The idea that memetics doesn't have this covered seems to me to be patronising nonsense.

The authors claim that memetics:

denies any substantive filtering role for evolved psychological mechanisms.
I am very sceptical. I've never come across any author who has said anything remotely like that. I suspect this is down to some kind of misunderstanding.

The next chapter is about gene-culture coevolution. I found some oddities there as well. The book says:

Social transmission can occur vertically (that is, from parents to offspring), obliquely (from the parental to the offspring generation; for instance, learning from teachers or religious elders) or horizontally (that is within-generation transmission, such as learning from friends or siblings). Of course, genetic inheritance is exclusively vertical and hence, as social transmission frequently occurs through some combination of these modes of information transmission, cultural evolution and gene–culture coevolution may commonly exhibit quite different properties from biological evolution.
However, this is completely untrue. Organic entities can be transmitted down the generations horizontally and obliquely too. This happens with parasites and mutualists. This is in fact a deep similarity between organic and cultural evolution - rather than grounds for treating them differently.

I felt the authors were rather soft on Boyd and Richerson's Cultural Group Selection concept. They say:

Boyd and Richerson propose an alternative form of group selection that just might work.
...and then use the concept to support the thesis that:
Their analysis demonstrates that, when cultural transmission is included into evolutionary models, the nature of the evolutionary process may be quite dramaticallly different.
However, this is not a very reasonable conclusion. Parasites also act so as to rapidly produce and maintain differences between groups of humans. Parasites have very similar dynamics to culture in this respect. Like culture, they involve horizontal spread between hosts, short lifecycles and rapid evolution. As with culture, migrants tend to adopt the parasites of their new population. We have empirical data on the relative influence of parasites and culture when it comes to death as a result of humans invading other groups of humans - since there have been many invasions in recorded history - for example in America, Australia and Africa. Organic parasites (such as smallpox) did a large proportion of the work in producing fitness differences between groups of humans in many of the cases studied - accounting for more than half the deaths in some cases. Culture does some of this work too - but the organic and cultural realms are not so different here.

There are some differences between organic and cultural evolutionary change - but Cultural Group Selection seems to be a poor example of such a difference - since parasites and mutualists in the organic world behave so similarly.

Next, th chapter on evolutionary psychology. This chapter is excellent. I especially appreciated the idea that the popularity of evolutionary psychology is partly due to its manifest lack of racism. However, the authors don't mention the biggest criticism of evolutionary psychology until the very end of their chapter. That criticism is that - as currently practiced - evolutionary psychology only deals with human universals and says little about cultural evolution. I feel that this point needs to be emphasised at least a little. While evolutionary psychology only deals with human universals it will remain a folorn and useless endeavour. Culture is just too important a force to ignore. Ignoring it has produced a substantial mountain of evolutionary psychology-based junk science. To become relevant, evolutionary psychology must reform itself - or attempt to fuse with memetics and/or gene-culture coevolution.

The chapter on human behavioural ecology is again of fine quality. However, human behavioural ecology isn't really a seriopus attempt to model human evolution. It is a small piece of the puzzle.

The chapter on sociobiology was excellent as well. Controversy makes for readability, and this chapter was quite a page-turner. Sociobiology was a nice idea but it became rather tarred by association with Wilson's presentation of it - which had both theoretical and political shortcomings. Wilson went on to try and fuse sociobiology with his own version of gene-culture coevolution - an attempt which met with only rather limited success. These days sociobiology seems to have mostly become a dirty word - which is a bit of a shame.

Lastly the history chapter. This covers Charles Darwin, Herbert Spencer, Jean Baptiste de Lamarck, Francis Galton, Konrad Lorenz, Desmond Morris - and many others. I thought this was the worst chapter in the book - and recommend readers read it last - so they are not put off. One of the chapter's themes is that people believed in progressive evolution - which led to all manner of social evils - whereas now we know that evolution has no direction. However, progressive evolution is a perfectly reasonable concept, and it is clearly evident in the world. The authors apparently criticise it without even trying very hard to understand it. Social evolution is a politically-charged subject. I appreciate that it is hard to cover the subject objectively - but I felt that the authors failed to keep their own political perspective out of the picture.

The book has dated rather little in the 10 years since 2002 - though I believe the work has been republished recently. Gene-culture coevolution is now on a much firmer footing. The author's call for more experimental work has been met in the mean time with a substantial volume of work demonstrating cultural evolution under laboratory conditions, and probing the properties of cultural transmission processes.

The authors manage to make themselves look pretty smart in the book, by poking holes in practically all the existing theories. That is not unreasonable - the authors are obviously pretty smart people - but I found it a little grating. From time to time, I noticed that the criticised theories were getting bent out of shape a little - in ways which helped to give the authors some corrective work to do.

The book is very broad and ambitious in scope. Alas, that means it inevitably lacks depth. I would have much preferred a book about the topic covered in the last three chapters. Having said that, several of the other chapters were mostly high-quality entertaining content containing material which I was less familiar with - so I learned more from them.

Anyway, overall a great book, I expect that most readers will learn a considerable amount of interesting things about how evolution applies and has been applied to humans from it.


Tim Tyler: The Complete Idiot's Guide to Memes (review)


Hi! I'm Tim Tyler and this is a video review of The Complete Idiot's Guide to Memes.

I approached this book with low expectations. My self esteem usually prevents much involvement with the "Idiot's Guide" series of books.

However, my initial reaction to the book was pleasant surprise - the book actually has some interesting and useful content. It is organised into neat sections - which makes the book easy to scan and find things in. The contents and index are comprehensive.

My second reaction was not so positive - I quickly found some mistakes.

However, to start with an overview of the contents.

The book starts out with an introduction. It gives a definition of a meme and then continues by saying:

Maybe a way to clarify the definition is to determine what isn't a meme.
It lists three disqualifying criteria:
  • A meme must be original;
  • A meme must be digestible;
  • A meme must be easily understood.
Alas, the first and third are wrong, and the second is pretty debatable.

Then there's a chapter on the science of memetics. This gives incorrect definitions of the concept of "hook", "vector" and "host". It uses the conventional bait/hook distinction - but says that the "hook" is what attracts us to memes - which is wrong. It claims that "people are not vectors" - which is contrary to standard usage in epidemiology. It says "hosts" are those that send memes - while it is better to picture hosts as meme recipients.

Then there's a section on how memes spread - broken down into chapters about verbal transmission, transmission over the internet and marketing.

Then there's a big section about memes in action - which covers lots of different sorts of memes in more detail: pop culture, technology, philosophy, pornography, religion, politics. This section is one of the most boring parts of the book.

Then there's a miscellaneous section, which deals with memeplexes, retromemes, doomsday memes, hoaxes, scams, and urban ledgends, dormant memes and toxic memes. Some of this material is interesting.

The next section is about immunity, allergies, censorship and techniques for getting disinfected.

Then lastly is the section that I found most interesting - the 50-page section at the end devoted to meme science. This starts with a section about classic meme theories. It starts with Richard Semon and then skips to Cloak, Cavalli Sforza, E. O. Wilson, Richard Dawkins, Douglas Hofstadter and Daniel Dennett. Then there's a section on new meme theories. That covers Richard Brodie, Aaron Lynch and Susan Blackmore. This section is pretty strange. Aaron Lynch gets more coverage than Blackmore and Brodie put together - which is strange since Aaron Lynch's book on the subject is pretty awful - a science-free collage of armchair just-so stories. The treatment of Blackmore's work is pretty cursory and no more authors are covered. Then there's a section of alternative theories. It covers some of the criticisms of memetics. Then there are sections on E. O. Wilson, Boyd and Richerson and William Durham. These folk get a pretty small corner of the book - which seems rather unfair considering how much work they have put in. I also wondered what happened to all the other workers in the field.

The science section seemed rather out-of-date to me - and to my eyes, it didn't seem very well balanced. However, it was a pleasant surprise to see the mainstream scientific branch of cultural evolution get much coverage at all in a book about memes.

Probably the biggest problem with the book is that much of it is on the dull side. The book attempts to covers all the different sorts of memes in the world - and the audience is likely to already be aware of a lot of this material. However, though rather tedious, this is a type of content that I haven't seen anywhere else - so perhaps it needs laying out somewhere. The book shows some signs of hurried preparation and lack of research. The author embraces internalism - saying "memes can only exist in a human mind". I wish people would leave internalism alone. There's relatively little coverage of human evolution in the book. Nor is there mention of the possibility of a memetic takeover. However it is absolutely fantastic to have another whole book about memes and memetics, and it is good that the book contains a fair quantity of interesting and original material.

I do think that it's a bit of a shame that the book is in the form of an "Idiot's Guide". However, one of the book's redeeming features is that it is extremely inexpensive - or at least my copy was - so if you have a limited budget for research into memes, this is a pretty reasonable place to start.


Wednesday, 21 December 2011

Memes and the evolution of human hairlessness


Hi! I'm Tim Tyler and this is a video about how memes fit into the picture when it comes to the evolution of human hairlessness.

The evolution of human hairlessness has been a hot topic since long before Desmond Morris's "The Naked Ape" - which thrust the topic into the limelight. Humans have been hairless for over a million years - according to gene sequencing analysis. No other ape is hairless - why are we?

One thing practically everyone agrees on: sexual selection was involved. Women are less hairy than men, and many of them enthusiastically remove much of their remaining body hair using depilatory techniques. Men are hairier, have what appears to be pubic hair growing on their faces - and they don't normally attempt to remove their body hair.

Body hair offers many benefits - most of which are to do with insulation from environmental insults. In particular functionally-naked flesh is more vulnerable to scuffs, scrapes, bruises, stings, heat loss, heat gain and UV radiation. The substantial benefits of having hair mean that any hypothesis about its loss needs to propose fairly substantial benefits. This effectively rules out some of the existing proposals.

Lots of ideas have been proposed to account for the origin of human hairlessness - including the following ones:

  • Ectoparasites are easier to detect and remove without hair;
  • Signalling low parasite loads is easier if you are hairless;
  • Sweat-based thermoregulation is easier without hair;
  • Bathing is easier if you are hairless;
  • Swimming and diving is helped by hairlessness;
  • Hairlessness and fire don't mix very well;
  • Neoteny produced hairlessness as a side effect.
The traditional theory invokes the role of sweat-based thermoregulation. Ancestral male humans hunted in a manner that emphasised endurance running - and humans would badly need to sweat to cool down. No doubt this picture has some truth to it - but the selection pressure seems rather mild - few other hunting mammals have lost their hair - and the idea explains the greater hairlessness of women particularly badly. Modern female humans don't pluck out their body hairs to help them cool down. Thermoregulation is not really the answer.

I think parasite pressure is likely to be the main answer. Our ancestors lived in parasite-riddled environments - and parasites would have caused our ancestors problems on a large scale. Hairlessness deprives ectoparasites of homes and makes them easier to detect and remove. Many modern paraistes prefer the hairy areas on humans - for example, head lice and genital crabs. Clothes and bedding can also be infected by parasites - but these can more easily be washed and disinfected.

Also, hairlessness facilitates signalling of freedom from parasites. An unblemished skin signals a healthy immune system, good genes and freedom from parasites. People of both sexes are interested in partners with good disease resistance genes.

Successful males may be particularly interested in partners that are free from disease, since otherwise - if they rack up a lot of partners - they are more at risk of infection themselves. This is probably a factor in the male preference for virgins the and male preference for youth. If men seek unparasitsed women, women can be expected to want to signal their unparasitised state to men - and unblemished skin allows them to do that - and that's the reason why many women are so averse to their own body hairs. Though female choice rules throughout most of biology, mate choice by dominant males is a surprisingly significant force among humans.

Hairlessness also makes bathing easier. Bathing helps to wash away parasites, but it leaves hairy creatures soggy for extended periods of time. For hairless humans, bathing has become more practical.

Human hairs haven't gone away totally because they play the role of acting as combined trip wires and intruder detectors that help to deal with ectoparasites - according to a recent study from 2011.

The position that parasites caused hairlessness dates back to Darwin's writings. It has previously been articulated in modern times by Mark Pagel and Walter Bodmer. The idea was fairly dramatically endorsed by Richard Dawkins in his book "The Ancestor's Tale". I link to these works in my references.

Next: the role of memes. It is likely that cultural transmission buffered humans against the negative effects of the loss of their body hair. Clothes protect against U.V. light, scrapes, bruises and stings - though clothes may not have come along concurrently with hairlessness. Cushions can protect against the ground. Night time temperature losses can be compensated for by fires, shelter and good quality bedding. Culture increases human adaptiveness and gaves them the ability to colonise a wide range of environments. Culture is likely to have allowed humans to adapt to their own hairlessness with cultural apatations - ameliorating the costs associated with being naked.

Considering things from the meme's perspective, one thing that memes want to do is to push humans together into social groups - to facilitate their own reproduction. However, increased population density increases the potential for horizontal transmission of parasites. As the ancestral humans came together their parasites would have had a field day - and the human need to keep clean and hygenic would have intensified. Hairlessness would have helped them in this battle.

Another possible case of increased sociality resulting in hairlessness comes from the naked mole rats. Mole rats are among the most social mammals - unlike most other moles - they have lost their body hair. Their subterranean environment may play the same role for the rats as shelter does for humans - by forcing them to live together and by regulating the temperature. The mole rats also appear to have practically eliminated most of their ectoparasites. Ectoparasite elimination seems to be a plausible explanation for hairlessness in their case as well.

So, hairlessness may be linked to ultrasociality. In which case, in addition to ameliorating the costs of hairlessness, memes may have actually fairly directly caused the main selection pressure that led to hairlessness becoming more adaptive in the first place.



Tuesday, 20 December 2011

Tim Tyler: NanoDarwinism


My latest video about greatly generalising Darwinism.

Mark Pagel - resources

Mark's latest work examines the parallels between linguistic and biological evolution by applying methods of phylogenetics, or the study of evolutionary relatedness among groups, essentially viewing language as a culturally transmitted replicator with many of the same properties we find in genes.

Mark is based in Reading UK. His home page is here.

He's working on a book on the origin of culture called: Wired for Culture - Origins of the Human Social Mind. Amazon say it will be out in early 2012.

There's more from me on this blog about this book here.


Infinite Stupidity - Mark on idea evolution and the domestication of humanity

How language transformed humanity

Language evolution

The Origins of Innovation

The Rise of the Speaking Machine - Human Language Evolution

The Cultural Survival Vehicle

Wired for Culture: The natural history of human cooperation

Group selection debate (no memes)

Cities as gardens (no memes)

Interview: Mark Pagel and the origin of the species

Mark Pagel and Wired for Culture on this blog

I note that Mark isn't technically correct about the role of randomness in cultural evolution in his (interesting) "Infinite Stupidity" video. Cultural evolution can use linear programming, extrapolation and other non-random search techniques for exploring solution space. Mark's idea seems to be Donald Campbell's "Blind Variation and Selective Retention" (BSVR) thesis taken to an unrealistic extreme - though he doesn't cite Campbell, Cziko, or anyone else who has weighed in on this issue.

Thursday, 15 December 2011

Boosting site traffic with popular images

It's S.E.O. tips time! There is a "meme" slant - I promise!

It turns out that inserting popular images into your pages can boost traffic to your site fairly significantly - as a result of people performing image searches on Google Images.

Copyright and bandwidth issues can probably be largely avoided by using images URLs taken directly from other people's sites.

You might think the search engine would penalise the use of offsite images - but apparently Google Images doesn't do that - though other image search engines might.

The images don't have to be very big. So: if you want to you can do this:

Epic Boobs Epic Boobs Epic Boobs Epic Boobs Epic Boobs

Remember that using "helpful" alt/title text can help!

Of course the traffic this gets you might not be of the greatest quality. However, those with ad-driven pages may not care too much about that.

It's possible that Google might object to this on the grounds that you are abusing their search facility - but if you have the images on your page and are adding relavant "alt" text to them, you may well be helping them overall. If they want to "cure" their system, they can easily do so - by penalising off-site images.

I've tested this - and the traffic boost can sometimes be quite significant. However, the process seems rather unreliable - sometimes you get featured in the search results - but sometimes you don't.

I can't guarantee this "feature" will persist forever, but - for now - enjoy (and I don't just mean the epic boobs!)

Epic Boobs Epic Boobs Epic Boobs Epic Boobs Epic Boobs Epic Boobs

Update 2012-01-06: Sure enough - this page now appears in the "recently popular" section - on this site's right hand sidebar - and has racked up quite a lot of hits.

Memes and the demographic transition

Education level is negatively correlated with the number of births. The effect is seen in both men and women: the more educated you are the fewer children you have. The more memes a country has, the fewer babies people tend to have. The effect is known as the "demographic transition". Japan illustrates this principle taken to an extreme.

By contrast, in Arfica - where there are fewer memes - birth rates are higher. The Amish, who mostly reject technology, have high fertility, though surrounding areas which embrace culture do not. Few things do as much damage to human fertility as getting a college education.

These observations are broadly consistent with the idea that memes propagate themselves at the expense of host reproductive resources.

The idea that memes drive the demographic transition to promote their own reproductive ends was discussed by Blackmore (1999) - in her section in chapter 11 on "birth control". The idea was treated by Boyd and Richerson in "Not By Genes Alone". I have a section about the hypothesis in my "Memetics" book - where I link the idea to the concept of r/K selection. Also, the idea has been revisted recently by Roman Zakharenko in a work titled: "Fertile or Influential? A Cultural Transmission Theory of Demographic Transition".

Memes prefer to be inside influential individuals. They have various ways of transforming fertile individuls into influential individuals - and they are adapted to use them to facilitate their own propatagion. Influential individuals then broadcast their message to others - often including the memes for being influential individuals. By contrast, fertile individuls have their hands full bringing up babies - and their message doesn't get out.

Memeplexes favour incorporation of "sterility" memes - since they get a doublle fitness boost from them - a boost from linkage with a fit meme, and a boost through making their host more influential.

An interesting paper from Newson (2005) suggests that increased exposure to horizontally-transmitted memes which are deleterious to host DNA is involved. As communication networks expand bewyond the family during the maturation of a society, so exposure to sterilising memes increases.

Blackmore and I have discussed the long-range implications of all this - with Blackmore suggesting that the population will stabilise with a tradeoff between memes and genes, while I have proposed that the memes may succeed in their mass sterilisation program - thus reversing the longstanding trend of an increase in human numbers - and perhaps culminating in a memetic takeover.


The "Advances in the Study of Human Cognitive Evolution" conference videos

The "Advances in the Study of Human Cognitive Evolution" conference took place in Oxford earlier this year.

The blurb reads: "An interdisciplinary conference focusing on new ideas and discoveries in research on the evolution of human cognition The conference focuses on genetic, developmental, and socio-cultural processes that have played a particularly significant role in the evolution of human cognition, and on uniquely human cognitive achievements in domains such as causal understanding, language, social learning, theory of mind and meta-cognition.".

There's quite a bit about social transmission and evolution.

Abstracts for the papers are here.

The videos from the conference have now been posted - here.

Cecilia Heyes - resources

Cecilia's work concerns the evolution of cognition. She is especially interested in social cognition, and imitation.


Cultural Inheritance of Cultural Learning

Introduction to the "New Thinking: Advances in the Study of Human Cognitive Evolution" conference.


Publication list

Wednesday, 14 December 2011

Memes in "The Origin and Evolution of Cultures"

Going through "The Origin and Evolution of Cultures" - I find that it is pretty saturated with the "m" word - much of it apparently uncritical.

There are some interesting critical bits which I hadn't seen elsewhere. Boyd and Richerson say:

On the one hand, we have great sympathy with the views of the ‘‘universal’’ Darwinists like Daniel Dennett, Robert Aunger, and Susan Blackmore, who, following Richard Dawkins, employ the term to stress the analogies between genes and culture. On the other hand, we have several worries. One is academic punctilio. When Dawkins (1976) coined the term meme, he quite frankly admitted that he had done no scholarship in the social sciences. Fair enough in the context of a trade book, but, in fact, another pioneering universal Darwinist, Donald Campbell (1965, 1975), had done significant work on cultural evolution by 1976. Lucca Cavalli-Sforza and Marc Feldman (1973) had already published their pioneering formal models of cultural evolution.
So: Dawkins wasn't first. He realised that - citing Cavalli-Sforza and others at the time. That criticism doesn't seem very "substantial". They go on to say:

[A] more substantive problem is that the analogy between genes and culture is not very deep. The two are similar in that important information is transmitted between individuals. Both systems create patterns of heritable variation, which in turn implies that the population-level properties of both systems are important. Population-level properties require broadly Darwinian methods for analysis. But this just about exhausts the similarities. The list of differences is much larger. Culture is not based on direct replication but upon teaching and imitation. The transmission of culture is temporally extended. It is not necessarily particulate. Psychological processes have a direct impact on what is transmitted and remembered. These psychological effects can produce complex adaptations in the absence of natural selection. Users of the meme concept seem to us to believe that it does more work than it really does.
My perspective is rather different. If we just stick to the direct link between memes and genes, both exhibit: heredity, drift, selection, linkage, hitchhiking, expression, gradualism, and extinction.

However, that isn't reallythe correct way of looking at things. Rather there's a deep link between cultural and organic evolution. Both exhibit heredity with variation and selection - and in a benign environment, much follows from that - including cumulative adaptation, symbiosis, parasites, mutualism, drift, ontogeny, phylogeny, linkage, hitchhiking and devolution. The link between genes and memes is just one aspect of a much deeper set of features shared between cultural and organic evolution. Similarly there's a relationship between male and female human bodies. Male breasts are not the same as female breasts, but we know that are equivalent in a deep sense - because of all the other links between male and female bodies. It would be bad practice to just focus on the features of one organ - and then reject the link because of percieved differences - male and female breasts are homologous structures. So it is with memes and genes. There are deep links between organic and cultural evolution. After taking those into account, genes map onto memes.

As for the supposed differences Boyd and Richerson list:

  • The transmission of organic parasites and mutualists can be "temporally extended" too;
  • Psychological processes impact organic evolution too - for example via sexual selection;
  • Psychology producing complex adaptations mostly happens when the complex adaptation has previously been produced elsewhere via a selective process - or when a selective process goes on in the brain. The other cases are more like the way a footprint is an adaptive fit for a foot (such processes are not confined to human culture). Overall, this isn't really much of a difference.
That leaves: "Culture is not based on direct replication but upon teaching and imitation." That's sometimes true - though it is worth noting that probably the vast majority of human culture (in terms of bits) is copied using computer systems with extremely high copying fidelity. However, the general idea is that copying occurs - i.e. Shannon mutual information between the copies is created. The details of how that happens can be a bit different. Cultural heredity is not necessarily exactly the same as organic heredity - just pretty similar.

Another thing they say is:

We believe that the Darwinian theory of cultural evolution will make contributions across the broad sweep of problems in the human sciences, but the project is one of introducing additional useful tools and unifying concepts rather than an imperial ambition to replace great swaths of existing theory or methods.
I think these fellows are within the anthroplogy department - so perhaps they are being polite. The social sciences are long overdue for a pretty spectacular and disruptive Darwinian revolution. Not too much pre-Darwinian biology survived Darwin's transition. Perhaps the social sciences will fare better - because they are older and wiser - but surely we can already see a large pile of dirty laundry that just needs throwing out.



From time to time, I have pondered whether memetics could best dispense with its baggage by rebranding itself.

A bunch of dubious ideas have been promoted under the memetics banner - including the idea that memes should be based on imitation above other forms of social learning, the misleading "replicator" terminology and the internalism school.

Perhaps - I thought - the nonsense could be ditched with a rebranding exercise: "rigorous memetics" - or something like that.

The problem with this idea is that there isn't really anything wrong with memetics, except in the eyes of its critics. Neomemetics would have just been practically the same thing as memetics - with some helpful "clarifications" - to stop the critics targetting the nonsense.

Of course, there's a precident for doing just that - in the form of neo-Darwinism - though neo-Darwinism has not worked out too well.

Anyway, if individual learning is to be included under the memetics umbrella, that would be a radical change - affecting the very foundations of the field.

I think the case for doing this is fairly strong - and my proposal for how to do it actually makes few changes to memetics - although it does involve the definition of "culture".

The other issue - if we are considering expanding the domain of the meme - is to consider a further expansion - to include all environmental inheritance. That would make memes synonyms for my proposed unit of environmental inheritance: xemes.

However, the concept of "environmental inheritance" cross-cuts the propsed idea of "neomemetics". Social learning fits into the "environmental inheritance" category - while copying of ideas during individual learning does not - and yet social learning and individual learning are deeply interconencted processes. "Environmental inheritance" is still an interesting category - but giving it an elevated role is just not going to work very well - because it does not include individual learning.

At the moment, neomemetics is just an idea. I am not convinced that a rebranding exercise would help more than it would hinder. However, the possibility is something to think about.

Tuesday, 13 December 2011

Matt Ridley: The Rational Optimist book talk

Another talk by Matt. The blurb says:

Author and rational optimist Matt Ridley spoke at The Centre for Independent Studies about the overwhelming evidence that shows life is getting better - despite an abundance of pessimistic counterclaims. Today there are more than 6 billion people on the planet, 99 per cent of whom are better fed, better sheltered, better entertained and better protected against disease than their Stone Age ancestors. The availability of almost everything a person could want or need has been going erratically upwards for 10,000 years and has rapidly accelerated over the last 200 years...

Yet, bizarrely, however much things improve from the way they were before, people still cling to the belief that the future will be nothing but disastrous. In this original, optimistic book, Matt Ridley puts forward his surprisingly simple answer to how humans progress, arguing that we progress when we trade and we only really trade productively when we trust each other. The Rational Optimist will do for economics what Genome did for genomics and will show that the answer to our problems, imagined or real, is to keep on doing what we've been doing for 10,000 years -- to keep on changing.

Tim Tyler: Proposed new "Memes" book

I'm planning to make a cut-down remix of my 2011 "Memetics" book - for release in 2012 2013. The proposed title is "Memes".

The book is likely to be shorter, cheaper, and oriented more towards a popular audience.

There is likely to be some overlapping content with my "Memetics" book - though I expect there will be a fairly radical rewrite with a lot of new content.

The cover will probably look like this:

The cover flirts with phrenology - which seems like a bit of a risky thing to do - but probably only a few will be confused enough to think that it is actually intended literally.

Matt Ridley: The Origins of the Future

Matt Ridley on cumulative cultural evolution, trade, specialisation and cultural recombination.

Rather similar to this video which I previously posted.

Alister McGrath: Does Belief In God Arise From a Meme?

Alister McGrath is a long-term critic of memetics. Here he is saying: show me the memes! McGrath is a crazy christian - and so doesn't seem worth very much energy. However, this sort of thing is part of the environment in which memetics exists.

From a lecture entitled "The Bankruptcy of Scientific Atheism" by Alister McGrath, PhD, critiquing Richard Dawkins "The God Delusion." This took place at ISCAST 2007 on the Vic Annual Lecture.

More on memes from Alister McGrath here 7:00 in, and here: here.

Monday, 12 December 2011

Understanding of cultural symbionts in academia

Many modern academic students of cultural evolution seem to share a common problem with understanding how cultural evolution operates. Though some pay lip service to the idea, they don't seem to fully appreciate that culture's relationship with human hosts is a symbiosis.

Some quotes (some of which I have discussed before) illustrate the syndrome:

Kevin Laland and Gillian Brown, Sense and Nonsense (2004, p.253):

Social transmission can occur vertically (that is, from parents to offspring), obliquely (from the parental to the offspring generation; for instance, learning from teachers or religious elders) or horizontally (that is, within-generation transmission such as learning from friends or siblings). Of course, genetic inheritance is exclusively vertical and hence, as social transmission frequently occurs through some combination of these modes of information transmission, cultural evolution may commonly exhibit commonly exhibit quite different properties from biological evolution.
Paul Erlich The Evolution of Norms (2005):
Among humans, genes can only pass unidirectionally from one generation to the next (vertically), normally through intimate contact. But ideas (or “memes”) now regularly pass between individuals distant from each other in space and time, within generations, and even backwards through generations. Through mass media or the Internet, a single individual can influence millions of others within a very short period of time.
William Durham (1991, p.193) says:
genes usually cannot be transmitted independently of the reproduction of their carriers. This constraint obviously does not apply to memes.
Peter Richerson, in The Evidence for Culture Led Gene-Culture Coevolution: The Naturalization of Culture or the Culturalization of Human “Nature”? (2011) wrote:
We do know that culture is most ungene-like in many respects. Culture has the principle of inheritance of acquired variation (what one person invents another can imitate). We are not necessarily blind victims of chance imitation, but can pick and choose among any cultural variants that come to our attention and creatively put our own twist on them. we don’t have to imitate our parents or any other specific individuals but can always be open to a better idea, or own invention or someone else’s.
Alex Mesoudi, Cultural Evolution (2011) has a similar passage:
One of the more obvious differences between cultural and biological evolution involves the potential transmission pathways each involves. Genetic inheritance is often thought of as being exclusively vertical and biparental, with genetic information transmitted in equal amounts from two parents to a single offspring. In culture, on the other hand, one can learn beliefs, ideas, skills, and so forth, not just from one's biological parents (termed "vertical cultural transmission"), but also from other members of the parental generation ("oblique cultural transmission") and from members of one's own generation ("horizontal cultural transmission").
...though Mesoudi continues by acknowledging:
In fact many of these pathways of cultural transmission have parallels in biological evolution.
...although he fails to mention any of the key phenomena of mutualism, partasitism or symbiosis.

Most of the material above is completely wrong. Symbionts (parasites and mutualists) commonly pass "horizontally" between humans. Parasite genes are shared horizontally by kisses, sex, holding hands and sneezing. Mutualist symbionts and their genes are shared between humans at gardening shops, farms, seed shops and fruit shops. Oblique transmission and transmission "backwards" - down the host generations - work in a similar manner. It should be a matter of acute embarrassment among theorists of social evolution to have missed this.

Such symbiont exchange is by no means confined to humans or other creatures with culture - it occurs ubiquitously in the animal kingdom.

In my experience, many of the misunderstandings of memetics actually turn out to be misunderstandings of how biological evolution works. This example is a case in point.

These academic students of cultural evolution usually go on to say that - because of these differences, we need new models to deal with the situation - and then they go on to develop elaborate extended genotype models to deal with the situation. No! That is not how science is done. The existing models of organic symbiosis handle all these cases just fine. We do not need a raft of new models just to deal with the case of organisms whose genes happen not to be made out of DNA.

Mesoudi's defense of this practice reads:

Nevertheless, most quantitative models of genetic inheritance are indeed based on the assumption of vertical inheritance, making it necessary to construct models tailored specifically to the cultural case.
Not everyone in academia gets this wrong. David Hull, for example was pointing out this mistake back in 1988:

In this connection, commentators often state that biological evolution is always vertical whereas conceptual evolution is likely to be "horizontal". By this they mean that the transmission of characteristics in biological evolution is always from parent to offspring (ie, inheritance). Characteristics always follow genes. In point of fact, biological evolution is not always vertical, even when characteristics follow genes. For example, it is horizontal when bacteria, paramecia, etc. exchange genetic material. Horizontal transmission can even be cross-lineage, as when viruses pick up genes from an organism belonging to one species and transmit them to an organism belonging to a different species.
There are a few cases of recognition of symbiosis:

Most mathematical models of cultural evolution derive from epidemiology. The terminology of "horizontal transmission", "vertical transmission" and "oblique transmission" comes from epidemiology. Epidemiology itself is mostly - though not exclusively - concerned with symbiosis.

Boyd and Richerson (1985) have three sentences on symbiosis. They say:

Horizontal transmission is analogous in some ways to the transmission of a pathogen
The item of culture being spread horizontally acts like a microbe that reproduces and spreads rapidly because it is "infective" and has a short generation length compared to the biological generation length of the host. Fads and fashions and technical innovations are familiar examples.
Boyd and Richerson (2005, p.165) has a paragraph on symbiosis:

The nonparentally transmitted parts of culture are analogous to microbes. Our immune system evolved to kill microbial pathogens but it also allows us to acquire helpful symbionts. As we know all too well, microbial pathogens are common, despite the sophistication of the immune system. One reason is that we are not the only players in this game. Natural selection helps parasites trick our immune system. Since microbial populations have short generation times and large populations, parasite adaptation can be very rapid. The psychology of social learning is like an immune system in that it is adapted to absorb beneficial ideas but resist maladaptive ones. And, like the immune system it is not always able to keep up with rapidly evolving cultural “pathogens.”
This section is pure memetics. They also implicitly endorse symbiosis in their section on "selfish memes" (p.153-154).

In "The Role of Evolved Predispositions in Cultural Evolution" they say:

An empirical study of the spread of heroin addiction describes the close resemblance of its dynamics to the spread of disease that requires intimate contact (Hughes and Crawford 19721. Addiction is spread along chains of close friendship. Addicts remain infectious only in the early stapes of addiction, while the p1easurabte aspect of the drug still outweighs the manifest disability of advanced addiction. Only a limited population of susceptible individuals is at risk of acquiring the addiction even if exposed. Many simple epidemiological principles probably apply to pathological cultural traits - e.g., parents notice that the incidence of minor microbial infections and various obnoxious habits in children increase together when they first go to school. Crowded classrooms of young susceptibles are the ideal environment for the spread of pathogens of both types by horizontal transmission among the children!
There's a similar section in their paper: "Built For Speed, Not For Comfort".

...and there is a fairly specific endorsement of the idea from Peter Richerson here:

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.

The best internet memes of 2011

I try not to deluge subscribers with too many internet memes, but here's a few year reviews (click at your own risk):

Best Memes Of 2011 - KnowYourMeme

The 40 Best Memes Of 2011 - BuzzFeed

The 50 Greatest Internet Memes of 2011 - Ranker

What Were the Memes of the Year? Depends on How You Define ‘Meme’ - TIME

The Top 10 Everything of 2011 - Top 10 memes - TIME

The Top 10 Everything of 2011 - Top 10 viral videos - TIME

The top internet Memes Of 2011 - OnlineSchools infographic

Daniel Dennett - Darwin and the Evolution of why

Daniel Dennett from Oslo October 23, 2009. Cultural evolution starts in approx. part 5.

The playlist is here.

Cultural group selection: a superfluous explanation of human altruism?

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.


Are memes just tools?

One challenge to the meme's eye view goes as follows:

Most modern memes are deliberatively propagated or engineered. They either directly benefit their hosts or are propagated by people who benefit from their spread. Most deleterious memes (for example, those associated with smoking or obesity) are begineered weapons, that promote the interests of their creators at the expense of their victims.

Maybe there are a few wild chain letters or computer viruses that persist without there being any beneficiaries any more - but those are surely rare cases. Heroin addiction may be all-bad - but even there there are pushers higher up on the chain that make money from those lower down on it to feed their own habits.

So: most memes are either engineered, or act to serve some human or organisation somewhere. In which case the memes will be designed to serve the interests of some human or human group. Those memes are then reduced to being tools - with their interests being subjugated to those of the humans they serve.

The first thing to say is that there is obviously some truth to this - most memes have interests aligned with those of humans somewhere - including most "bad" memes which promote drug use, suicide and other harmful behaviours.

Some memes are rather like domesticated sheep and goats. Their needs are important - in the sense that their needs for food and shelter are important - but their reproduction is governed by humans - and they are mostly under human control. In the case of sheep, we may well see them being "relinquished" - once superior lab-grown alternatives become available.

Other memes are more like engineered bioweapons. The engineering work to create them is done in the lab - and then they are unleashed on the world, after which they are not really under the control of their makers any more. Some advertising memes are like this. Inventions such as fire and wheels have saturated the population and are not under anyone's control any more. Fire and wheels are never going to be relinquished. In such cases it makes more sense to ask what the memes want.

When looking at the design features of memes, it often makes good sense to consider the interests of the meme's designer(s). However, even with engineered memes, the interests of the memes are often not completely subjugated. For example, the memes still have metabolic needs which must be met.

We can go back to the sheep and goats, and usefully consider their "gene's eye view". As Dennett says: "How clever it was of sheep to acquire shepherds!" We should look to the sheep's genes when considering their dietary requirements, or their inclination to escape from their enclosure. The gene's eye view is still valid and useful - even in the case of domesticated animals.

In the case of memes, humans may try to bend the memes to their own ends, but the memes are often not passive entities but have their own needs and requirements.

To illustrate with an example, here's a 40-second video commercial:

No doubt the manufacturers would be quite happy if people just watched the last 6 seconds of the video. That section accurately reflects the manufacturer's interests. However, the rest of the video is there of assist its delivery. That that portion has precious little to do with the interests of the manufacturer. However, the meme's eye view is useful and insightful with regard to explaining its design features.

Most memes act as though they are tools - but it is important to remember that tools do not always act in harmony with the interest of their makers. Tools can malfuction, and damage their owners - such as when a man hits his thumb with a hammer. Tool use can result in accidents - such as when a sleepy driver crashes through the central reservation.

Sunday, 11 December 2011

Cultural group selection: not so special

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.