Hi! I'm Tim Tyler and this is a review of this book: Ever-Expanding Horizons: The Dual Informational Sources of Human Evolution by Carl P. Swanson.
The book says it its preface that is concerned with one question - namely: "What is the DNA of cultural evolution."
It gives its answer half way through the book - on page 87 - by saying:
A sociogene is defined here as a mental concept, a structured image, arising from one or more acts of experience, molded into shape and integrated with other sociogenes by the action of the central nervous system and from which information is extractable, expressible, and transmissible within the context of a social mileau.
"Sociogene" is a term that the author included in an earlier 1973 book - so it predates the term "meme".
The book dates from 1983 - so that's seven years after the selfish gene, two years after Lumsden and Wilson's Genes, Mind, And Culture book, two years after Cavalli-Sforza and Feldman's book Cultural Transmission and Evolution an d one year after The Extended Phenotype.
The author says that their book is based on reading an article written by V. Potter in 1964 called "Society and Science". He quotes from that article, saying:
the processes of natural selection and survival of ideas in cultural evolution are analogous to the natural selection and survival of DNA molecules in biological evolution, and that ideas are the key to understanding cultural evolution just as DNA molecules are the key to understanding biological evolution.
The author compares "sociogene" to the term "meme" and says that their meanings are similar. Today, the term "sociogene" as the author uses it would be described as being equivalent to an internalist conception of a meme. Sociogenes would today be called "neuromemes" by externalists.
Today on the internet references to the term "meme" outnumber references to the term "sociogene" by about 180,000 to 1. "Sociogene" was longer, mostly quite a bit later, and it wasn't attached to The Selfish Gene. As a result, it has practically gone extinct.
The term did have some advantages. "Sociogene" is pretty self-explanatory, while "meme" is not. The author contrasts sociogenes with biogenes - and this neatly and implicitly makes it clear that both are types of gene. The term "sociogene" allows terminology such as "sociophenotype" and "socioallele" to be used - while students of memetics can't adapt those two terms for the cultural realm quite so easily. Although I mostly approve of the idea of a "sociogene", the term biogene: that's the whole idea that DNA is biological and culture isn't, whereas if you actually think about it properly, culture is a biological phenomenon - so call calling DNA genes "biogenes" is just a bad way of thinking about things.
The book is mostly easy to read, fine and clear. It cites lots of literature - including the books I mentioned earlier - except for The Extended Phenotype. The author seems to have reasonable understanding of cultural evolution - though the book just looks at the issue of hereditity - and so many of the more common topics of cultural evolution are left unaddressed. Some parts of the book suffer from the flaw of being a bit boring. For example, the book goes on about the history of the universe and the mechanics of DNA copying for many pages - most readers will not be interested in such material.
The book takes a kind of internalist stance. Its unit of cultural heredity is defined as being inside a brain. The author never confronts the main challenge facing enthusiasts of internalism - which is what to with your conceptual framework once culture starts to be copied by machines. I guess computers were not considered to be so significant back in 1983.
The author uses his own "sociogenotype" term pretty sloppily - to refer to the culture of human individuals and of society. From a modern perspective, that looks as though he is using the term "genotype" to describe the heritable material of whole ecosystems, which seems a little confusing.
Some parts of the book have dated. For instance, the author says:
we know of no significant correlation between traits of known genetic origin and those of cultural derivation.
These days, that sounds odd. Most people in the field could probably come up with some examples of such traits pretty quickly.
To summarise, this is a nice book - though it seems likely that only those looking at a historical perspective are likely to seek it out.
Interesting news reports on new findings on the topic of the basis of long term memory. It finds that memories are stored in synapses by a self-copying prion-like protein.
A portion of the structure is self-complementary and—much like empty egg cartons—can easily stack up with other copies of itself. CPEB thus exists in neurons partly in the form of oligomers, which increase in number when neuronal synapses strengthen. These oligomers have a hardy resistance to ordinary solvents, and within neurons may be much more stable than single-copy "monomers" of CPEB. They also seem to actively sustain their population by serving as templates for the formation of new oligomers from free monomers in the vicinity.
Finding a form of molecular copying to be implicated in the basis of long-term memory is no surprise - but it is an interesting and important finding, and it looks as though it may help to illuminate the nature of some of the low-level Darwinian processes that go on in the brain.
Darwinism is getting everywhere these days. I had a look at quantum Darwinism recently. My analysis:
In quantum physics, wavefunctions are constantly being copied with variation. Quantum Darwinism essentially proposes that wavefunction collapse represents a form of selection - and that the resulting evolution of the observed universe thus has a Darwinian character.
Quantum Darwinism has been developed mainly by Wojciech Zurek (pictured on the right). It is described in more detail here and here.
Quantum Darwinism appears to be fairly heavily dependent on wavefunction collapse. Wavefunction collapse is a controversial process. So far, no real evidence has been found favouring the idea. It looks like a bunch of made-up nonsense - as was pointed out by Hugh Everett and his Many-worlds interpretation.
Zurek apparently largely rejects many worlds = writing:
There are two key ideas in Everett's writings. The first one is to let quantum theory dictate its own interpretation. We took this "let quantum be quantum" point very seriously. The second message (that often dominates in popular accounts) is the Many Worlds mythology. In contrast "let quantum be quantum" it is less clear what it means, so - in the opinion of this author - there is less reason to take it at face value.
Can quantum Darwinism work without wavefunction collapse? The problem is that there's then no equivalent to death or resource limitation. However, there is still differential reproductive success.
Can one have Darwinism without death? There is still heredity, variation and differential reproductive success. That does tick most of the boxes of Darwinism.
I think it has to be conceded that quantum Darwinism is reasonably accurately named. Whether a Darwinian perspective tells us anything that we didn't already know in this case seems more debatable, though. It may not make a difference to predictions - but it might have an impact on visualisations of the process.
Of course, if the "many-worlds interpretation" ever collapses - so to speak - quantum Darwinism might become a lot more interesting.
Ingold has some specific criticisims - among them:
Secondly, there is the question of what actually evolves. For ‘evolutionary biology’ it is normally taken to be the so-called genotype. Does there, then, exist some cultural analogue of the genotype? Opinion on the matter is divided even among ‘evolutionary biologists’ themselves, as Robert Aunger testifies in his comment
Yes: the cultural genotype is the memotype. It is rather less clearly delimited than in the organic realm, since cultural creatures are sometimes less clearly delimited than organic ones are. However organic organisms do not always have clear boundaries either - for example, consider ants or the Portuguese Man o'War.
the very assumption that information is pre-encoded, in genes or culture, prior to its phenotypic expression in the forms and behaviour of the individuals who carry it, implies that there exists some ‘reading’ of the genetic or cultural ‘code’ that is independent of the social and environmental contexts in which those individuals grow up and live their lives.
Not really. English is a memetic code that maps from memes to meme products. However: is English "independent of the social and environmental contexts in which those individuals grow up and live their lives"? Not really - there are also French and Spanish speakers and English is constantly being modified by those who speak it. This just seems to be a misunderstanding.
Are we to understand that cultural information is transmitted, from head to head, independently and in advance of its expression?
That depends a bit on what you mean. A recipe can be transmitted from head to head without ever going through its main meme expression process - namely baking a cake. However, there's a sense in which behavioral imitation involves at least some meme expression processes - involving creating behavior and then observing it and reconstructing corresponding motor actions. However, it is rare for culture to be copied independently of its expression.
How can a theory of cultural evolution, modelled on the principles of ‘evolutionary biology’, be other than completely circular? Following in the footsteps of other neo-Darwinian culture theorists, Mesoudi et al. define culture as transmitted information (ideas, knowledge, beliefs, values, skills, attitudes) that affects the behaviour of individuals. They then go on to announce that there is ‘ample evidence that culture plays a powerful role in determining human behaviour and cognition’ (331). Culture is anything that determines what humans think and do, ergo what humans think and do is determined by culture!
That argument just doesn't seem to make any sense at all. Culture is NOT defined as being "anything that determines what humans think and do" by Mesoudi et al. - they also permit non-social learning and genetics to influence human behaviour. Tim continues with:
Nor is this circularity limited to neo-Darwinian reasoning about culture. The same goes for its thinking about genes. To establish the genotype of an organism, ‘evolutionary biology’ works backwards from its outward, phenotypic form and behaviour by factoring out variation due to environmental experience so as to arrive at a context-independent description, only to declare that its form and behaviour are expressions, within a particular environmental context, of an evolved genotype. The concept of ‘trait’, whether applied to genetic or cultural characters, at once embodies and conceals this circularity.
WTF? I don't think Tim Ingold knows what he is talking about! This is what an anthropologist criticising evolutionary biology looks like? I think Tim should stick to subjects he knows something about.
Medoudi et al. offer their responses to all this here. They describe Ingold's article as containing "unhelpful misrepresentation and scaremongering".
This podcast is pretty boring. Memes start in part 2. Ingold has the idea that evolutionary biology needs to be combined with developmental systems theory - and various other things - in order to create a viable theory.
The main problem with that is that we already have a perfectly good, highly viable theory that is spending far too much time sitting around not being applied.
The current situation is that immense retardation in the social sciences is occurring - through the lack of a Darwinian theory of cultural change.
Scientists should probably roll out the current best shot at a Darwinian theory of culture across the social sciences fairly soon. I mean, 150 years of pre-Darwinian thinking in the social sciences is enough - right? The social sciences should at least get onto the Darwinian bandwagon. Some of the more esoteric aspects of evolutionary theory can be postponed - if it actually helps with that basic mission.
Tim Ingold doesn't seem to me to be part of the solution. Maybe he has a revolutionary unified theory of biology up his sleeve, but from what I can see, it doesn't look like it, and nobody should delay rolling out Darwinian culture theories on his behalf. This makes Tim part of the problem.
The other thing to say is that, in my experience, most people who claim that developmental systems theory is important to integrate into evolutionary biology often have a poor understanding of how useful evolutionary biology can be with no modeling of developmental processes at all. Evolutionary biology kind of has a "slot" into which theories of development can be fitted. A lack of knowledge of development thus has very little impact on progress in evolutionary theory. Population genetics is the same. We can do meme frequency analysis just fine without understanding development at all.
David Sloane Wilson criticises the "religion as virus" application of memetics - 39:40 into this video. He says:
The meme concept, of course, has a number of meanings, and the
most general definition of "memes" is just newspeak for culture.
Use the word culture, take it out, and put in the word "meme".
and so the broad usage, that broad usage of "memes",
"cultural evolution", of course applies not just to parasitic memes,
"memeplexes", the group level, just
about all of the different evolutionary hypotheses can be given a
meme formulation when "meme" is used in that general formulation.
There's more from him on the subject of memes 13:10 minutes in.
David Sloane Wilson's position on this is not unreasonable - and I agree with him.
Here's his main talk:
David Sloan Wilson at Beyond Belief: Enlightenment 2.0
The fallacy of Dennett's argument also undermines his other imperialist hope--that the universal acid of natural selection might reduce human cultural change to the Darwinian algorithm as well. Dennett, following Dawkins once again, tries to identify human thoughts and actions as "memes," thus viewing them as units that are subject to a form of selection analagous to natural selection of genes. Cultural change, working by memetic selection, then becomes as algorithmic as biological change operating by natural selection on genes--thus uniting the evolution of organisms and thoughts under a single ultra-Darwinian rubric:
According to Darwin's dangerous idea...not only all your children and your children's children, but all your brainchildren and your brainchildren's brainchildren must grow from the common stock of Design elements, genes and memes.... Life and all its glories are thus united under a single perspective.
But, as Dennett himself correctly and repeatedly emphasizes, the generality of an algorithm depends upon "substrate neutrality." That is, the various materials (substrates) subject to the mechanism (natural selection in this case) must all permit the mechanism to work in the same effective manner. If one kind of substrate tweaks the mechanism to operate differently (or, even worse, not to work at all), then the algorithm fails. To choose a somewhat silly example that actually played an important role in recent American foreign policy, the cold war "domino theory" held that communism must be stopped everywhere because if one country turned red, then others would do so as well, for countries are like dominos standing on their ends and placed one behind the other--so that the toppling of one must propagate down the entire line to topple all. Now if you devised a general formula (an algorithm) to describe the necessary propagation of such toppling, and wanted to cite the algorithm as a general rule for all systems made of a series of separate objects, then the generality of your algorithm would depend upon substrate neutrality--that is, upon the algorithm's common working, regardless of substrate (similarly for dominos and nations in this case). The domino theory failed because differences in substrate affect the outcome, and such differences can even derail the operation of the algorithm. Dominoes must topple, but the second nation in a line might brace itself, stay upright upon impact, and therefore fail to propagate the collapse.
Natural selection does not enjoy this necessary substrate neutrality. As the great evolutionist R.A. Fisher showed many years ago in the founding document of modern Darwinism (The Genetical Theory of Natural Selection, l930), natural selection requires Mendelian inheritance to be effective. Genetic evolution works upon such a substrate and can therefore be Darwinian. Cultural (or memetic) change manifestly operates on the radically different substrate of Lamarckian inheritance, or the passage of acquired characters to subsequent generations. Whatever we invent in our lifetimes, we can pass on to our children by our writing and teaching. Evolutionists have long understood that Darwinism cannot operate effectively in systems of Lamarckian inheritance--for Lamarckian change has such a clear direction, and permits evolution to proceed so rapidly, that the much slower process of natural selection shrinks to insignificance before the Lamarckian juggernaut.
From "Bully for Brontosauraus":
I am convinced that comparisons between biological evolution and human cultural or technological change have done vastly more harm than good — and examples abound of this most common of all intellectual traps. Biological evolution is a bad analogue for cultural change because the two are different for three major reasons that could hardly be more fundamental.
First, cultural evolution can be faster by orders of magnitude than biological change at its maximal Darwinian rate — and questions of timing are of the essence in evolutionary arguments.
Second, cultural evolution is direct and Lamarckian in form: [t]he achievements of one generation are passed directly to descendants, thus producing the great potential speed of cultural change. Biological evolution is indirect and Darwinian, as favorable traits do not descend to the next generation unless, by good fortune, they arise as products of genetic change.
Third, the basic topologies of biological and cultural change are completely different. Biological evolution is a system of constant divergence without subsequent joining of branches. In human history, transmission across lineages is, perhaps, the major source of cultural change.
From "Life's Grandeur" page 219:
In this sense, I deeply regret that common usage refers to the history of our artifacts and social organizations as “cultural evolution.” Using the same term - evolution - for both natural and cultural history obfuscates far more than it enlightens. ... Why not speak of something more neutral and descriptive — ‘cultural change,’ for example?”
...
But cultural change, on a radical other hand, is potentially Lamarckian in basic mechanism. Any cultural knowledge acquired in one generation can be directly passed to the next by what we call, in a most noble word, education.
...
This uniquely and distinctively Lamarckian style of human cultural inheritance gives our technological history a directional and cumulative character that no natural Darwinian evolution can possess.
...
human cultural change is an entirely distinct process operating under radically different principles that do allow for the strong possibility of a driven trend to what we may legitimately call “progress”
...
The common designation of “evolution” then leads to one of the most frequent and portentous errors in our analysis of human life and history – the overly reductionist assumption that the Darwinian natural paradigm will fully encompass our social and technological history as well.
Gould said in a 1996 radio interview with Susan Blackmore:
Hi. I'm Tim Tyler - and this is a review of this book: The Theory of Cultural and Social Selection, by Walter G. Runciman.
The book is essentially sociology with memes. The main topic is sociology, but the terminology and explanatory framework used by the book is based on memetics.
The book covers religious and political topics. It deals with feuds, rituals, slavery, Marxism and marriage customs. It discusses stasis, group selection, convergence and the goal-directedness of social change. There are sections about the role of Darwinism in social science, resistance to Darwinism and the history of the field.
To the extent that the book has a main theme, it's that natural selection and cultural selection need extending to social selection. In the book natural selection is based on genes, cultural selection is based on memes and social selection is based on practices. Genetic traits are evoked, memetic traits are acquired and social practices are imposed. Cultural selection and social selection are said to not be reducible to natural selection.
There is a kind of case to be made along these lines. A lot of the work on the topic has been done by people interested in microevolutionary phenomena and population genetics. For them small-scale cultural phenomena are more immediate and accessible than society and history are - and they can be more easily explored experimentally. As a result, there's a bit of a bias towards psychology - and away from sociology, history and the world of cultural macroevolution. It is easy to imagine how sociologists might feel that their field is being unfairly neglected by selectionist theorists.
However, it seems to me that Runciman pushes this case to unrealistic extremes. His rejection of the term "socio-cultural evolution" seems to be unreasonable to me. I don't like his proposed terminology for social evolution either. What he calls "practices" I just call "memes" - the same term as is used for the units of cultural evolution. Using a different term makes very little sense. The author's "meme-practice evolution" terminology seems almost as bad as the "gene-culture evolution" terminology - both represent an inappropriate muddling together of different types of category.
The relationship between social evolution and small scale cultural phenomena is a lot like the relationship between micro- and macro-evolution. Macro-evolution is essentially made up of many micro-evolutionary phenonmena. It is true that there are emergent phenomena that come from considering things at a different scale. It is also true that group selection might potentially introduce new effects at the larger scale. However, group selection still seems to be relatively insignificant - and macroevolution is largely microevolution writ large.
The author mentions multi-level selection in the context of his framework. He discusses cultural group selection - and briefly attempts to sketch a case for it. However, he doesn't seem to present social selection as a synonym for cultural group selection. Group selection - if significant enough - would provide a theoretical basis for the type of split the author is going for. However, it hardly presents sociology with a firm foundation. Without being based on group selection, social selection seems to be pretty similar to cultural selection, and the emphatic split between them advocated by the author doesn't really seem to be warranted.
Next: memes. The book is saturated with memes. They are mentioned on almost every page. Runciman produces what seems to me to be a perfectly reasonable rationale for using the memetics terminology, and then views sociology with meme-tinted spectables. It would have been better if he had used it to describe social selection too. However, I think that Runciman should be praised and congratulated for adopting memes.
I can't easily review most of the sociology in the book - but I can review its memetics. The memetics in the book seems to be pretty basic. Runciman has deleterious memes, but there seems to be no the meme's eye view, or meme recombination. There's a discussion of memes as symbionts, but it draws what I think is the wrong conclusion. Runciman identifies the "viral" aspect of memetics, but then criticises it for falsely implying that memes are deleterious. He also criticises it by saying that viruses are transmitted by a single exposure, while memes may require multiple exposures that act to reinforce each other. These criticisms don't apply to other kinds of organic symbiosis, though. For example, when a lone sheep tastes a pleasing mushroom it might require multiple exposures before is acquires a taste for them and starts to actively seek them out and distrubute mushroom spores in its feces. Taking multiple exposures before a relationship with a symbiont is established is pretty common for food symbionts - and it has nothing specifically to do with cultural evolution, and so does not represent much of a disanalogy between the cultural and organic realms.
Runciman goes on to give some examples of where he thinks that the symbiosis perspective fails. The first example he gives does exhibit the logistic growth curve found in epidemiology - but Runciman says it more closely resembles detoxification that an infection. Through the lens of symbiosis, his example looks more like a case of disinfection. It is actually an example of disinfection by one cultural symbiont caused by infection with another one. There are similar phenomena in the organic realm - such as when bacteria in a pro-biotic yogurt is used to displace rogue gut bacteria. The second example describes a case where one group fails to acquire a contagion from another group - and Runciman claims that an "infection" theory would have predicted greater spread. However, there are phenomena such as adaptive and genetic immunitity to consider. The failure of some particular germ to spread doesn't invalidate the whole theory of germs. Reasoning in this way, Runciman fails to adopt the symboisis perspective and doesn't mention parasitism, mutualism or symbiosis for the rest of the book. This is a pretty central part of memetics and is one of the main things that distinguishes it from other theories of cultural evolution.
However, for most of his applications, Runciman doesn't really need an advanced version of memetics with recombination and symbiosis. He can get by with a version based on bean-bag genetics - and that's exactly what he does.
Runciman's discussion of progress is acceptable. He at least acknowledges the phenomenon.
For me the main problem with the book was that it was dry and not very well written. Runciman writes in a rather flowery style that dances around the point with digressions and only rarely seems to get down to the meat. The book is broken up into chapters and numbered subsections. This layout doesn't really help readers who wants to skim read or flick through the book to find things of interest to them. There is only one diagram. Alas, I was rather glad when the book was over.
Unfortunately, this is not a great book. However, Runciman is one of the few sociologists who has actually got as far as adopting a selectionist perspective - and so other sociologists who might want to follow him don't have a lot of similar reading material to choose from - and so some may find something of value here. Those more interested in an evolutionary perspective probably won't find the book so useful. This is really much more a sociology book than the title might suggest.
What's wrong with the concept of indirect reciprocity?
I think it mixes two very different things together.
One is where a positive reputation results in cooperation - A is nice to B and then C is nice to A.
The other is where generosity is misplaced - A is nice to B and then B is nice to C.
The first is rational, the second is normally irrational - and is typically down to resource-limited cognition.
Indirect reciprocity is also a bit of an oxymoron. The word "reciprocity" doesn't really apply to indirect situations unless the benefits are eventually returned to from whence they came.
It is much better to put these two types of interactions in different categories. That's what I do - with the concepts of virtue signalling and overgeneralisation.
Nowak achieved some not-so-desirable publicity recently with his role in the "Kin Selection debacle" in Nature.
Nowak discusses cultural evolution near the start of the first video, but - as with most writers on the subject of cooperation - Nowak seems to be more interested in game theory than symbiosis and cultural evolution.
This video shows that Richard Dawkins was still going strong on memes in 2010.
At 08:25, Richard points out that genetic advantages are not the only possible explanation for the existences of religions - they could also exist for the benefit of the memes, or due to differential reproductive success of religions themselves.
Alain de Botton proposes importing educational strategies, pilgrimmages, preaching (and numerous other things) from traditional religions into secular life.
Many people have already imported key technologies like yoga, meditiaion and group chanting from the world of traditional religions and into the secular realm.
It does look as though there will be other types of secular "religions" which have nothing to do with theology. Some of the modern end-of-the-world cults closely resemble secular religions.
I expect we will see more religious-style cults based around creating/worshipping future artificial intelligences fairly soon.
I don't usually write very much about memes relating to sex or religion. Sex and religion are major areas to which memetics can be usefully applied - but writing about sex seems somehow cheap - while writing about religion probably means that my writing will get dated. Also, both areas have already been covered well by others.
However, I should probably offer my 2 cents on the issue of whether religion is good for those who are religious.
Being religious is certainly correlated with health, life satisfaction, having kids and many other fine traits. Corrleation is not causation - but this isn't an area where it is easy to perform randomised, controlled trials.
Most religion has probably been adaptive for most of its believers in the past. However, there's also another possibility to consider: that religion might be adaptive for a minority of those who promote it - but not so much for average believers. This is a picture of religion as manipulation. Not so much manipulation directly by memes, but rather manipulation by other humans using memes. We know of many cases in which religious influences have been used by those in power to help prevent violence and revolutions. In the past, rich English folk gave a lot of money to the church - and the church used this money to build cathedrals - where the poor could go to feel grand - and where they could be told how stealing from the rich people was wrong. Turning down requests for donations may not have been so wise - the church was a powerful and influential force. A similar situation led to the promotion of Buddhism within China - if happiness lies within, then you don't need to steal the rich people's stuff. This picture still has religious memes spreading because they are adaptive to DNA genes - but it would be more like smoking or obseity - where the benefits accrue to only a few. The beneficiaries may not necessarily have been priests - they could also have been "friends of the church" - politicians, royalty, the rich, etc.
It also seems obvious that - in societies dominated by a single religion - there would have been immense pressure to conform. Not being religious under such circumstances would typically have been very, very bad for both you and your DNA. If this is a parasite it is a pretty weird one - since it makes infected hosts punish the uninfected. The movie Shivers portrayed such a parasite - so it's not totally impossible, I suppose. However, even then, lacking "religious" cultural symbionts is still bad for you - if you are in an environment where there are may others who have "religious" cultural symbionts.
It looks as though most major religions have been beneficial to some religious humans historically in at least one of these ways. Maybe these religions will become maladaptive in modern times - but that's a bit of a different issue.
Ben Cullen pointed out that many religions can be expected to be beneficial - on grounds associated with parasite ecology - long ago, in a paper entitled: Parasite Ecology and the Evolution of Religion. Ben pointed out that a lot of religion is transmitted with a significant vertical component. Vertically-transmitted memes tend to coevolve with their hosts to become more benign. The hosts adapt to ameliorate their negative aspects, and both benefit from host reproduction - so their interests become more aligned. Of course, some religions spread horizontally better than others - this argument applies with reduced force to ones that are good at spreading horizontally.
All this is not really news. David Sloane Wilson has been pointing out that religions show every sign of being adaptive to their hosts for a long time.
Anyway, I think that the Dawkins speculation that major religions are like deleterious viruses - that spread because they spread - has been proven wrong - so wrong that Dawkins should probably recant. It was an interesting idea - but an incorrect one.
I've dragged myself into the group selection debate a little recently - because of the scale of the level of interest in cultural group selection among other scientists in the field of cultural evolution.
I think cultural group selection is probably mostly irrelevant fluff that distracts people from what is actually going on. I have no argument with multi-level selection theory. However, the problem is the old one - the conditions under which the idea can generate group-level adaptations are rather rare in sexual species - due to migration and breeding. However, I do think that cultural group selection is almost certainly one of the most interesting attempts to revive group selection for quite a while.
Today, I was amused to find a video of Richard Dawkins on the topic of the group selection revival - from 2010:
Dawkins says of E. O. Wilson and D. S. Wilson (20 munites in):
I think they are just confused
...and...
The so-called "new group selection" is just kin selection or in some cases reciprocal altruism under another name. For reasons best known to himself (which I can't understand) D. S. Wilson thinks it's helpful to rephrase it in terms of group selection. How it can be helpful when he's reviving a word which has been debunked and is simply grafting that word onto the very thing that did the debunking - namely kin selection and reciprocal altruism and various other things - it seems to me be to be utterly unhelpful, to be totally misleading to students and it's deeply regrettable that E. O. Wilson should have teamed up with him in this way.
Hah! I think D. S. Wilson may be getting this response because he regards kin selection and reciprocal altruism as being a special case of his form of group selection.
These papers appear to be mainly about ordinary group selection - not Wilson's "trait group selection". These papers are very confused, incidentally. I'm not sure where to begin with them - but the Ed Wilson material seems to be missing the concepts of parental manipulation and offspring manipulation as alternative mechanisms to group selection for creating eusociality.
The second paper invokes group selection caused by cultural effects - saying:
Group selection is an important force in human evolution partly because cultural processes can create variation between groups, even when they are composed of large numbers of unrelated individuals. A new cultural “mutation” can quickly spread within a group, causing it to be very different from other groups and providing a decisive edge in direct or indirect between-group competition.
Cultural group selection is not vulnerable to the criticism Dawkins gives. That is a straight-forwards revival of Wynn-Edwards-style group selection - though possibly applying the idea to cultural symbionts. It is definitely not genetic kin selection or reciprocal altruism dressed up in misleading clothing.
Dawkins winds up saying (at 26:40):
Everything in Darwinism is gene selection - and it's just unhelpful and confusing for somebody as influential as Ed Wilson to suddenly turn around and say he's started thinking about group selection again. What was he thinking of - confusing the issue like this?
That looks like a kind-of fatal statement to me. Sureley nobody who understands multi-level selection would dream of making a statement as strong as that.
Group selection could be illustrated by finding genes that are deleterious to the individuals possessing them but good for the groups they are in - or by finding adaptations caused by genes like that. Group selection does not contradict gene selection. The idea that gene selection and group selection are mutually exclusive is just a simple fallacy.
Richard Dawkins interviews Dan Dennett for "The Genius of Charles Darwin", the Channel 4 UK TV program which won British Broadcasting Awards' "Best Documentary Series" of 2008. The first 20 minutes of the interview has a lot about cultural evolution.
The latest paper from Henrich, Boyd and Richerson is called "The puzzle of monogamous marriage". It ponders the puzzle of monogamous marriage - how monogamy has spread while wealth inequality has increased.
Much of the paper is devoted to showing that monogamy is good for society-level fitness. They invoke cultural group selection to explain monogamy's spread.
Slavery seems like a suitable point of comparison. This is also widely banned - despite the fact that the richest might be expected to benefit most from it.
Wife inequality is seen as more of a moral issue than wealth inequality - and technological growth independently fuels wealth inequality.
Is the spread of spread of monogamy down to cultural group selection? I'm sceptical. It is true that in the democractic, religious and political revolutions and invasions that have spread monogamy a whole buch of memes gets supressed at once. However, describing this as being a form of group selection seems a bit controversial. A whole bunch of birds went extinct at once when mammals reached New Zealand. However, few would describe that as being a form of group selection. The invading animals wiped out the natives bacause they were fitter than them - not because of group-level effects.
Looking at large groups of memes going extinct during a major mass extinction event isn't terribly good evidence for cultural group selection, IMHO. In general, one group of organisms systematically wiping out their neighbours is just evolution as usual. Group selection - at least of the type that is controversial among biologists - is a more demanding concept than this.
The outcome shows that the monogamy meme bacame fitter as civilization progressed. If it could additional be shown that monogamy lost out to polygamy within groups, that would then qualify as evidence for group-level selection. However, the paper doesn't do that, and the idea that the polygamy meme wins within groups is probably simply false. In which case, group selection is not clearly needed as a hypothesis to explain the results.
A simple explanation for monogamy is democracy. Monogamy is deleterious for 90% of males and probably most females too. The few males it benefits may be powerful, but they are simply out-flanked by the rest of society. This explanation is simple, obvious - and it doesn't invoke group selection.
Memetic altruism is the most obvious thing to look for if looking for evidence favouring cultural group selection. At the moment, people see things that aren't explained by existing theories of altruism, and then invoke forms of group selection. However, it seems to be that this happens largely because they don't have a decent list of the known causes of human altruism. That seems to be largely because of a widespread incomplete understanding of memetics. Account properly for the existing known causes of altruism and group selection theories have a lot less work to do.
Authors Mark Earls and Alex Bentley explore how ideas, behaviour and culture spread through the simple means of doing what others do.a
Listen to the audio file of the full event here.
I generally use "selection" terminology. However, this terminology has some problems, and in this post we will take a look at them - and then consider whether better terminology is available.
Selection implies a selector
One problem with using the term "selection" is that it fairly strongly implies a selector.
The "selection" terminology arose from generalising "artificial selection" to "natural selection". Artificial selection makes reasonable sense - because there's a human selector doing the selecting, but with natural selection there's often not a selector. Talking about "natural selection" represents a kind of "agentification" of nature.
Of course sometimes there really is a selector. In female choice, agents do literally select their mates. However, if an asexual bacterium divides, there's not really any selecting agent - the environment.
Agentifying nature is not a dreadful problem.
Survival or death?
The selection terminology seems kind-of ambiguous about whether individuals are being selected for survival or death. In some respects this is appropriate: sometimes mates are selected for sex, sometimes they are selected for rejection - and natural selection is often selection for death. However the use of selection coefficients makes it plain that selection is a positive force - indicating what is retained. However, the grim reaper obviously doesn't work that way. Death has a blacklist - not a whitelist. This mixture of ambiguity and wrongness seems rather confusing.
Is nature even choosing?
The term "selection" pretty strongly implies choosing between alternatives. However it is not always clear that that is what is going on. Nature doesn't so much choose organisms as score them, expressing its approval with a certain number of offspring. A score can be represented by a series of selections, but it's a bit painful. Also, when generalising Darwinism, more problems along these lines arise. New genomes can be made by extrapolating or interpolating. Consequently, the next thing to try may be something not tried before. Such cases are poorly described as being "selections".
Organism disempowerment
It has been said the idea of nature "selecting" makes the organism seem impotent. Rather than the organism being rated by its environment, organisms rate their environments, and if they don't like them they migrate to new ones. This perspective puts the organism more in charge - rather than picturing organisms as being at the mercy of their environment.
Alternatives
Those are the alleged problems that I have heard about. I expect most readers will find at least some points to sympathise with.
John Wilkins has proposed "sorting" and "filtering" as alternatives that avoid agentifying nature.
"Culling" is a term that could be used to refer to "selection by death".
None of these really provide a term suitable for use in a generalised version of Darwinism. Generalised Darwinism still normally features gradualism, but there, it seems difficult to go far beyond vague terms like "modification" or "adjustment" - e.g. "the heritable information was slightly modified". Such vagueness may be accurate, but it isn't very catchy.
The other thing to say is that "selection" terminology has huge inertia - and a failure to use it would probably hamper communication with many readers.
For those unfamiliar with it, RationalWiki covers a range of scientific and political topics, providing commentary on them.
They have a large Pseudoscience section. It is rather like a version of QuackWatch oriented towards scientific topics.
The site features articles on numerous "fringe" subjects such as cryonics - which apparently is never going to work - and Transhumanism - which they characterise as "people assuming that because it can be imagined, it must be possible".
They have a section on memetics. As might be expected, it is pretty awful.
They start by approvingly citing the "criticism" of memetics from semiotics. To quote from my response here:
The semiotics students are correct to say that memes are signs - provided we use the definition of the term "sign" from within semiotics - which is - pretty confusingly - different from the usual English usage of the term. However, they don't seems to have any kind of coherent case against memetics. It seems to be more that they would prefer to use the terminology of semiotics to describe memes - even though the evolutionary biologists got there decades before them, and have a far more relevant discipline behind them.
They cite the mostly-daft criticisms of Luis Benitez-Bribiesca - focussing particularly on the issue of whether cultural evolution features sufficiently-high copying fidelity to support cultural evolution. I give this criticism a few sentences here.
This has not been a viable criticism for decades now. The bibles and languages (and their associated phylomemies) prove conclusively that the critique is mistaken. Among serious students of cultural evolution apparently only Dan Sperber ever took this critique at all seriously.
They also have a brief section on memetics in their section about "Scientific mysticism". It is positioned in the midst of a rant about abuses of "selfish genes". This section on memes is pretty awful as well.
They complain that in the internet era few memes go extinct - apparently unwaware of the facts that much evolution merely involves changes in frequency of traits, and that plenty of data loss still goes on on a regular basis - as computer hard drives crash and people fail to save their work.
They repeat the daft objection that:
Thus, the high rate of "memetic mutation" should predict mostly evolutionary noise with little room for natural selection"
They say that:
Memetics ignores the evolved cognitive architecture of the human mind and other models of cultural evolution such as gene-culture co-evolution.
Really. Dawkins cited the work of a number of existing cultural evolution theorists in The Seflish Gene - and was plainly inspired by some of their work. Dennett and Blackmore cite the work of these other theorists too. Indeed, practically every memetics author I can think of since 1976 has done the same. Perhaps these folks should go and read my book on memetics - which clearly places memetics in the context of other theories of gene-culture [sic] co-evolution.
They finish by saying that memes provide:
an intuition pump built on circular reasoning that generates unfalsifiable nonsense that happens to sound very pretty.
It remains unfortunate that people get into such silly muddles over memetics. Many of those in the field of cultural evolution are doing a spectacularly poor job of helping with public understanding of their own field. More explanatory material targeted at laymen seems to be urgently needed.
The article goes on to say:
One of this cult's prophets, Ray Kurzweil, seems to almost willfully misunderstand biological evolution to posit technological "evolution" as its outgrowth.
Ray Kurzweil gets it - but the RationalWiki editors plainly don't have a clue what they are talking about in this case.
One thing that critics of Richard Dawkins have repeatedly identified as problematical is the notion of "selfishness".
Some - OK, Mary Midgely - just didn't get the metaphor:
Genes cannot be selfish or unselfish, any more than atoms can be jealous, elephants abstract or biscuits teleological.
Others apparently propose that these concepts should be ditched. Here is David Sloan Wilson:
Saying goodbye to selfish genes and memes involves questioning everything that has been associated with these concepts and reviving what they seemed to deny: the concept society as organism.
I think the concept of "selfishness" is just fine in this context:
The term "selfishness" means promoting your interests without concern for the interests of others. So: "selfish genes" refers to genes promoting their own interests without concern for the interests of other genes - and "selfish memes" refers to memes promoting their own interests without concern for the interests of other memes. If you don't think genes have "interests", recall that referring to "gene interests" is just a shorthand for referring to the propensity of genes to catalyse their own reproduction. Similarly if you don't think that genes can be "concerned" about the interests of other memes, recall that that is just shorthand for actually promoting them.
This raises the issue of to what extent genes and memes are actually selfish. Some genes and memes fail to promote their own interests. Those aren't selfish because they aren't even active - so not all genes and memes are selfish. Most of the mechanisms promoting altruism to others don't apply to genes. Looking at the list of viable explanations for why humans-cooperate most of them don't apply to such entities. Genes and memes could potentially be manipulated into being nice to others of their kind - but it is not easy to come up with cases where this actually happens.
So, is looks as though most selectively-maintained genes and memes are indeed selfish. We could engineer genes or memes that promoted the interests of other genes or memes at their own expense. They could arise by chance mutations. However, such genes and memes are rare. So: the concept of selfishness in this context seems to be both clear and useful.
Neither Dan Agin nor David Sloan Wilson seem to have much of a handle on what it means for genes or memes to be "selfish". This is despite David Sloan Wilson's article purporting to unravel the mystery of "What Do Selfish Genes, and Memes, Really Mean?"
Richard Dawkins' idea is fine. David Sloan Wilson fails to articulate a coherent case against the concept - apparently through not groking its intended meaning.
David Sloan Wilson wants to link the concept to group selection. If genes benefitted groups at their own expense they would be behaving less than 100% selfishly. Wilson promotes the idea that group selection is common or important - and so apparently thinks not all genes are 100% selfish. I don't think that was ever the claim in the first place, though. Unselfish genes can arise from mutations - or through the environment changing unexpectedly. The idea is that selfishness is common, not that every single gene is selfish. Anyway, this certainly doesn't a reason for ditching the concept of gene-level selfishness.
It is worth noting that group selection simply doesn't tend to result in "unselfish" genes. While one can imagine genes that are good for groups rather than themselves, group selection would produce genes that are good for themselves that also happen to promote the interests of groups. The crusade against selfish genes in the name of group selection appears to be simply misguided.
Lastly, here is Peter Godfrey-Smith. Peter is the author of a book-length rant against Darwinian agenthood: "Darwinian Populations and Natural Selection". He says "selfish genes" are a "paranoid narrative":
Agential description of evolution can accompany real theoretical progress. This language can be used to quickly express contrasts between theories and models that can then be described more precisely. It can be used to steer the listener away from one family of models and explanations, to another. I don't deny its communicative role, and perhaps a heuristic role in exploring options quickly. In the mid to late 20th century, a change in the application of agential terms to evolution accompanied shifts in evolutionary thinking that were important. Some mid 20th century biology had seen an uncritical treatment of high-level entities, such as groups, species, and ecosystems, as evolutionary units. The reaction against that tendency featured close attention to evolutionary change at the level of individual genes (Hamilton 1964, Williams 1966). Genes became new objects of agential description – tiny and invisible strategists. Two kinds of agential narrative have a special psychological potency. The first is a paternalist schema. Here we posit a benevolent agent, often a large one, who intends that all is for the best. This category includes various Gods, the Hegelian "World Spirit" in philosophy, and stronger forms of the "Gaia" hypothesis, according to which the whole earth is a living organism. The second schema is a paranoid one. Now we posit hidden agents, often small, pursuing agendas that cross-cut or oppose our own interests. Examples include demonic possession narratives, the sub-personal creatures of Freud's psychology (superego, ego, id), and selfish genes and memes. And while it is true that sometimes there are large and kind agents or small and nefarious ones at work, the psychological appeal of these ideas means that we tend to take up such stories too readily and run with them too far. The account of evolution in terms of "selfish genes" (Dawkins 1976) is a paranoid narrative of this kind. It relegates other entities in evolution, such as whole organisms, to the role of mere "vehicles."
I must say that I am rarely struck by a novel enough idea that my first reaction is “wow.” This is one of those instances. There is something profoundly intellectually satisfactory in suddenly seeing disparate phenomena like Augustine’s god and Dawkins’ memes as different aspects of an all-too human tendency to project agency where there is none.
Alas, many philosophers seem to delight in persistently misundersanding this idea.
Hi! I'm Tim Tyler, and this is a review of this book: Genes, Mind and Culture by Lumsden and Wilson.
Genes, Mind and Culture was one of the first books published by scientists on the topic of cultural evolution. It came out about five years after Richard Dawkins had published The Selfish Gene - in 1976.
The book is pretty dated, and most people buying it will probably be doing so in order to get a historical perspective on the topic.
The book has over 400 pages. These are pretty densely packed with mathematical models, which render much of the book pretty unreadable by most of its audience. The models are not well presented. In some cases they may be acting partly to create a veneer of respectability.
Lumsden and Wilson make the case for a scientific study of culture based on biology. The book introduced the concept of a "culturegen". They define this as follows:
A culturegen is a relatively homogeneous set of artifacts, behaviours or mentifacts (mental constructs having little or no direct correspondence with reality) that either share without exception one or more attribute states seelcted for their functional importance or at least share a consistently recurrent range of such attribute states within a polythetic set.
From this you might begin to detect something of Lumsden and Wilson's style. While their own definition of a culturegen is awful, readers can understand its usage in the rest of this review by considering it to refer to memes or meme products - in the form of socially transmitted behaviours or artefacts.
The book then focused heavily on the epigenetic rules by which genes influenced what culturegens were adopted by their hosts. Like modern evolutionary psychologists, the authors were interested in the factors that make cultures similar everywhere. However, they did try to go beyond these commonalities and account for cultural differences. Their approach is based largely on population genetics.
One thing their book became known for is its "leash" metaphor. They write on page 13:
genetic natural selection operates in such a way as to keep culture on a leash.
In a subsequent section titled "Can culture have a life of its own?" they claimed that the establishment of deleterious culturgens in the population for extended periods of time could be demonstrated to be impossible - suggesting that epigenetic rules favouring the adoption of beneficial culturgens would be violated and that they would exert some kind of pressure which would alter the culturgens into a more favourable form. This idea was subsequently identified by some opponents as pinpointing where Lumsden and Wilson had gone wrong in their analysis.
The authors also wrote: "Culture slows the rate of genetic evolution". We now know that this is not correct either.
In one of the best parts of the book, the authors offer an analogy for understanding cultural evolution based on island biogeography. In this analogy, islands represent human minds and archipelagos represent societies. Culturgens act like organisms colonising the islands. The reader is thus invited to transfer their knowledge of the dynamics of island biogeography into the cultural realm. This idea is an excellent one - although picturing brains as islands makes them seem rather passive and picturing ideas as colonising organisms makes them seem perhaps too active and agent-like.
Island biogeography might seem as though it is an esoteric subject - but many students of evolutionary biology pick up a smattering of knowledge about the topic as part of the process of learning about evolution. Islands represent natural evolutionary experiments, and so are of particular interest to evolutionary theorists. Darwin's famous visit to the Galápagos islands has also helped to put island biogeography in the limelight.
However, although they do have a chapter devoted to it, Lumsden and Wilson don't do very much with this (excellent) analogy. Had they based more of their work on it, their book might have been a lot better.
Part of the book's problem involves failure to apply the principles of reductionism. Lumsden and Wilson obsessively pursue the idea of a gene-cultural cycle - corresponding to a series of cycles of ontogenetic development followed by acculturation. Only by looking at this complete cycle can the whole process be understood, Lumsden and Wilson apparently believed. Most others divided cultural evolution from organic evolution and treated these as two separate but partly-interacting processes. Because Lumsden and Wilson don't divide the topic up in this way, they get rather bogged down with the enormity of trying to understand everything all at once. The result is that they make relativelty little progress in actually understanding how cultures evolve.
Another way of looking at the book is as an attempt to shore up sociobiology against its critics. Sociobiology seemingly tried to explain everytrhing in terms of genes. Of course, that approach doesn't work too well for culture, which is not inherited via DNA genes - and culture is an important determinant of behaviour. So: sociobiology needed fixing, by applying a patch to deal with culture. However, the authors attempted to apply standard sociobiology strategies to the topic - by tracing how everything was affected by genes. While this approach is not a totally unreasonable one, it seems like a rather biased research strategy. Instead of looking at culture and considering how best to explain it, the researchers used their existing sociobiology toolkit and attempted to apply it to culture. While it is perfectly possible to ask after the basis of social learning in DNA genes, it turns out that there's another highly-productive approach to studying how culture evolves = which involves considering culture as a partially independent instance of an evolutionary process, following the rules of universal Darwinism. Lumsden and Wilson totally missed this approach - apparently through their eagerness to apply their existing sociobiology toolkit and look at the genetic basis of cultural phenomena. Much the same approach was used by Cosmides and Tooby a decade later, with much the same messed-up result.
These problems put Lumsden and Wilson's work off the main path that lead to the modern understanding of how cultures undergo Darwinian evolution and coevolve with human genes. The models Lumsden and Wilson presented did not do much useful work. Most subsequent authors have not built significantly on their efforts - and those that did mostly went off the rails in a similar way.
This review will stop here. If you want a more in-depth review than this one, the late John Maynard-Smith wrote a good review of this book in 1982, which was republished in his book "Did Darwin Get It Right?" You can probably find his review online.
Figs show how symbiotic visitors can transform a flower into something rather different - a swollen enclosed garden. The inside of a fertile fig typically looks like this:
Over evolutionary time, coevolution with the enclosed wasps has transformed the fig's flower. This transformation acts as a parable for what has been happening with the human cranium for the last three million years.
The story of the fig and its wasp is told in a relatively recent documentary "The Queen of Trees". A preview is available - in the form of these videos:
It may well be pirated, but currently the whole documentary is available on YouTube here.
I've previously drawn a connection between the enlarged human crainum and the domatia created by ant plants - here and here.
In memetics, the enlarged human cranium is a type of hollow whose primary "purpose" is accomodating symbiont visitors (memes). As such it resembles the plant swellings known as ant domatia - which are built by the host plants to provide accomodation for ants.
Domatia resemble human skulls, and ants resemble out cultural symbiots - with genetic material composed of memes.
Interestingly, ants of the species Allomerus decemarticulatus create artificial corridors between the domatia of their host plant (Hirtella physophora) to allow them to safely move between them.
What lets ideas move safely from brain to brain? Why: books, telecommunications and the internet! So: here we have the ant equivalent of the internet - based on the crainum-domatia analogy.
The highways are fiercely defended - and the native ants can trap and kill marauding insects that alight upon them.
Pictures
Video
The defence of the highways is shown in the following video:
This is an amazing ant domatia story - I plan to see if I can milk it.
I haven't posted LordImmolation's meme videos here before - so here they are:
The last video starts off talking about The Naked Ape and The Moral Animal - but gets onto the topic of memes towards the end.
Like many critics of evolutionary psychology, LordImmolation points out that the "environment of evolutionary adaptedness" is best thought of as being a spatially-diverse patchwork of many different environments - which is true, but doesn't seem to be a show-stopping criticism.
The real problem with evolutionary psychology so far has been its focus on human universals - and its near-complete neglect of cultural evolution. This makes it into a kind-of joke science of psychology and human behaviour - since it misses out so much of the topic it is supposed to be studying.
As LordImmolation says, evolutionary psychology looks fixable - just add memetics.
In memetics, the enlarged human cranium is a type of hollow whose primary "purpose" is accomodating symbiont visitors (memes). As such it resembles the plant swellings known as ant domatia.
Here's evolutionary psychologist Steven Pinker attempting to explain the same phenomenon of an enlarged cranium without mentioning symbiosis:
Pinker does invoke technology, language, and "division into cultures" - but these are just assumed, and there's no mention of how they fit into a biological or evolutionary framework.
Symbiosis had a hard time being accepted by biologists. Cultural symbiosis is similarly facing a struggle for recognition that mirrors the way it was widely ignored by biologists until the 1960s.
In the 1960s, it was mostly raw evidence (the evidence that mitochondria contained DNA) that finally got the theory of symbiosis accepted into the mainstream, and killed off the dogma that Fisherian bean-bag genetics could account for living systems - which had dominated evolutionary theory up to that point.
The analogous development in the realm of cultural evolution would consist of the discovery for the neuromeme.
However... this isn't the 1960s. We already know about symbiosis. We have an enormous quantity of data, and huge machines with which to analyse it. There is no good reason why symbiosis in the cultural realm should be a neglected idea.
There is really no good reason why the study of cultural evolution should continue to lag so far behind the study of organic evolution. People should just not still be proposing theories of cultural evolution that don't include basic phenomena - such as symbiosis and recombination.
The reasons why such phenomena are currently neglected boil down to ignorance and stupidity. Scientists in the field who are unaware of these phenomena should just wake up.
The criticism of memes starts at 53:50. The whole thing is really too ridiculous to comment on. I'll just quote:
Dennett complains that Aping Mankind caricatures a controversial idea he develops: cultural memes. The Darwinesque concept originates in Dawkins's 1976 book, The Selfish Gene. Memes are analogous to genes, Dennett has said, "replicating units of culture" that spread from mind to mind like a virus. Religion, chess, songs, clothing, tolerance for free speech—all have been described as memes. Tallis considers it absurd to talk of a noun-phrase like "tolerance for free speech" as a discrete entity. But Dennett argues that Tallis's objections are based on "a simplistic idea of what one might mean by a unit." Memes aren't units? Well, in that spirit, says Dennett, organisms aren't units of biology, nor are species—they're too complex, with too much variation. "He's got to allow theory to talk about entities which are not simple building blocks," Dennett says.
The video has a Q&A here. Memes are discussed 19 minutes in.
After taking cultural evolution into account, human genetic evolution (i.e. the evolution of human DNA) has accelerated in recent times - as a result of a number of factors:
The population has exploded, resulting in vastly more opportunities for positive mutations to happen;
Genes are poorly matched for the environment - resulting in directional selection pressures;
Shielding protects mutations from selection - allowing them to persist in the population;
So: it is rather strange to see the opposite case being made. Here's Steven Jones, claiming that the evolution of human DNA is effectively over.
Steve claims that selection by death between the ages of 1 month and 21 years has much reduced - which is true in many areas of the world. He claims that selection by differential reproductive success has reduced somewhat - which also seems to be true, to some extent.
However, he then says that the effects of genetic drift are reduced - as a result of larger population sizes and less isolation. This is true - but reasoning from there to reduced levels of evolutionary change gets things rather backwards. Small population sizes results in stochastic sampling effects - which eliminate genetic variation. Larger population sizes result in less of this elimination of variation, resulting in more of the variation introduced by mutations persisting. So, while it is true that larger population sizes prevent a trype of evolution due to sampling errors, larger populations also allow mutations to persist better than small populations do.
These days, we don't have to rely on hand-waving arguments to settle this point. We have data on evolutionary rates from molecular evidence which allow us to see both the current rate of change and the amount of change since humans diverged from our common ancestors with chimpanzees.
the rate of human evolution over the past few thousand years is far greater than it has been over the past few million years.
The article also says:
Comparing the amount of genetic differentiation between humans and our closest relatives, chimpanzees, suggests that the pace of change has accelerated to 10 to 100 times the average long-term rate