Monday, 3 October 2011

Tim Tyler: On the gene-meme relationship


Hi! I'm Tim Tyler, and this video about the meme-gene relationship.

Memetics is largely based on the idea that there is a relationship between memes and genes. The relationship is based on the idea that genes are the things that carry heritable information in organic evolution - and so we need to have some term for the carriers of cultural inheritance - and the term "meme" is the one that was selected by Richard Dawkins and has subsequently become the dominant term.

Memes are like genes in a number of ways. They carry heritable information down the generations. They are subject to mutation. They are capable of recombination. They change in frequency due to favorable or unfavourable selection. They are subject to drift. They exhibit linkage disequilibrium and engage in hitchhiking. They are expressed. They are potentially immortal. Memes often compete with alternative forms - sometimes called allomemes. There are meme pools, much as there are gene pools. Meme flow is very similar to gene flow. Phylomemetics is the cultural version of phylogenetics. There are memetic algorithms - which are similar to genetic algorithms. There's a meme's eye view which is similar to the gene's eye view. There is - or at least there should be - a science that studies memes in the same way there is a science of genetics that studies genes.

However, there are also a number of ways in which memes are not like genes. Memes are not made of DNA. They are not arranged in linear strings. There is no equivalent to a base pair. There are not a small number of codes which translate between the heritable material and phenotypes, but rather thousands of such codes. 99% of genes are represented in DNA - with only a small fraction being stored in databases. With memes it is more the other way around - with many memes are stored in databases. Memes are often not obviously divided into multiple chromosomes. Memes are often easy to change deliberately, genes are often challenging to change deliberately. Genes are often transmitted with high fidelity. Most memes are too these days, but there are some types of memes that are still subjected to very distorted transmission. Memetic engineering is very common - genetic engineering is still relatively rare.

The best perspective is probably that genes and memes represent sections of heritable information in different media in which Darwinian dynamics can take place. Similarities arise from the shared Darwinian dynamics while most of the differences arise from the differences between the media of inheritance.

However, many people seem to insist on treating the relationship between memes and genes as an analogy - and this leads to them to seek out the points of disanalogy. Then they often reject the relationship on the ground that the analogy doesn't work properly.

The link between genes and memes is one the main things that distinguishes memetics from one of the main strains of cultural evolution in academia - spearheaded by the researchers Boyd and Richerson.

Here is what Boyd and Richerson wrote in Not By Genes Alone (2005, p.81):
We encourage you not to think of cultural variants as close analogues of genes but as different entities entirely about which we know distressingly little. They must be gene-like to the extent that they carry the cultural information necessary to create cultural continuity. But, as you will see, this can be accomplished in most un-gene like ways.
We even have the one-time meme enthusiast Bruce Edmonds, saying:
I claim that the underlying reason memetics has failed is that it has not provided any extra explanatory or predictive power beyond that available without the gene-meme analogy.
These kinds of comment raise the issue of whether the gene-meme relationship is worthwhile - or whether it just causes too much confusion. This seems to be a no-brainer to me. The relationship between genes and memes goes pretty deep, and is obviously worthwhile. The failure to embrace it may have contributed to the poor penetration of topics like linkage-based memetic hitchhiking and the meme's eye view in academia. Boyd and Richerson's advice to think of their cultural variants as being "different entities entirely about which we know distressingly little" appears to be simply awful to me. We should be making use of our knowledge of evolutionary dynamics from genetics - not ignoring it and starting afresh.

The relationship between memes and genes is one facet of a much deeper relationship between memetics and genetics. The main problem with understanding cultural evolution in the world is that people fail to appreciate the depth the this relationship. This problem extends into academia. For example, earlier this year we have Peter Richerson saying this:
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, o[u]r own invention or someone else’s.
These comments appear to illustrate a lack of appreciation of the depth of the relationship between memes and genes. Acquired variation can be inherited in the organic realm too - such as when a dog gets fleas and then passes them on to their offspring. That is not what biologists usually mean by the term "the inheritance of acquired characteristics" - but it is the same type of inheritance of acquired characteristics that is most commonly found in memetic evolution: acquiring an idea and passing it on is essentially same phenomenon as acquiring a symbiont (such as a parasite) and passing that on.

Humans can pick and choose the diseases they acquire - to some extent - as well as the ideas they acquire. Both organic and cultural realms have immune systems, disease resistance and disease avoidance. There is not so much of a difference there either, it seems.

Animals subject to organic evolution are not "blind victims" of chance either - they can choose which symbionts they form associations with - in a very similar manner to the way in which humans choose their memetic symbionts.

As for only being able to choose parents in the cultural realm - we don't have to acquire the same parasites as our parents - we can collect different ones. Nor need we necessarily acquire the same food symbionts - if a new foodstuff comes along we can form a symbiosis with that foodstuff instead. Other creatures have similar food symbioses - for example ants. So, being able to select who you inherit symbiont genes from happens in organic evolution - in just the same way as it happens in memetic evolution.

So, the points Peter mentions to highlight the differences between memes and genes and illustrate how memes are "most ungene-like in many respects" mostly turn out to be deep similarities instead - once you properly grasp the concept of a meme-gene symbiosis. If you fail to grasp that then memetic evolution does indeed look very different from organic evolution - but only because you have not yet got a proper handle on the relationship between them. This is not to say that there are no differences between the memetic and organic realms - just that the similarities overwhelm them, abundantly justifying emphasizing the relationship between memes and genes.

Academia will have to eventually embrace the relationship between memes and genes. A failure to understand this relationship appears to be the cause of many current conceptual problems. Indeed, understanding the full depth and extent of this relationship, is really fundamental to understanding how culture evolves.


1 comment:

  1. You say that the relationship between genes and memes goes pretty deep. This is child-like from someone who has spent so much time on this.

    I've referred you to p.112 of The Extended Phenotype to see Dawkins give 5 cast-iron reasons why memes and genes are not the same. I'll review a few for you:
    1. The Weismann Barrier - even this tenet of classical neo-Darwinism is under threat from the work on protogenes and epigenetics but let us say (for now) that in the world of random mutation and genes there is a Weismann Barrier, this is clearly not the case when it comes to culture. Feedback, conscious and foresighted feedback drives culture far mor than any 'random' processes you can highlight, and over highlight. Dawkins is aware of this, and no doubt you are as well. On this point alone culture is a neoLamarckian process, and Stephen Jay Gould (a more rounded intellectual than Dawkins on these issues) rightly called culture "the Lamarckian juggernaut" because of the pace of change and the ability to adjust, or in the terms of Lamarck "the inheritance of acquired characteristics." However, cultural change and response occurs through technology and nano-trading so we have processes of nanoLamarkism at play, and these are different processes to those highlighted by Darwin. I would urge you to dig out a copy of The Extended Phenotype and become well versed in overcoming these 5 points, you'll need to if you want to take memetics out of the pseudoscience realm.

    2. In A Devil's Chaplain wrote that humans (and only humans) have the gift of foresight "something utterly foreign to the blundering short-term ways of natural selection."

    Utterly foreign. In the BBC Profiles video while promoting the book he said "The human brain is the only possible engine of departure from Darwinian principles, and it really is."
    Dawkins and Dennett (in lecture and interview) both acknowledge that humans "are the only/first intelligent designers on the tree of life." As I have said previously the question is no longer design (which evolution is the answer to) but drive. What are the causal forces that move humans, and their thought around?

    You are saying it is essentially the same system that underpins evolution that is also for culture, despite a number of core and lasting structural issues, the Weismann Barrier, directedness, fidelity, etc being ones you and others have not been able to overcome.

    You have words, and a lot of them but the last time I looked word manipulation wasn't the measure of science, it is law, mechanism, sophisticated theory and even equation. Can we arrive at such a standard for culture and the social world of humankind? Absolutely. However, it will involve a lot more rolling up of sleeves and doing the real digging and not the 'cut and paste' pseudoscience that characterises memetics.

    You think that Academia will have to eventually embrace the relationship between genes and memes. They haven't and they won't Tim because beneath the veneer there is no depth. Read p.112 of The Extended Phenotype and even Richard Dawkins agrees with me. Right now, so does the world of Academia as well.