Time to put Andrew Brown to pasture

October 19, 2011 • 8:03 am

Many of us who have endured the columns of Andrew Brown at the Guardian feel that it’s time for the man to move on.  His opinions lurch all over the place (usually, however, centered on the evils of atheism and the benefits of religion), but the writing is so absolutely dreadful that it’s hard to believe that someone pays him for his prose.  When I read his latest post,”On Belief’s new look, and old arguments,” I finally decided that he needs to go.  It’s not that he attacks atheism and defends religion here—for he doesn’t—but he just rabbits on and on about evolution without seeming to understand it.

Brown praises Dawkins’s The Selfish Gene (agreed!) and argues that the idea of memes has not been fruitful (also agreed!), but then loses the plot when he gets to one of Dawkins’s best books, The Extended Phenotype.  If you’ve read that book, you’ll know that it’s about the adaptive effects that genes within an organism can have when they act outside the body of that organism.  That is, an animal’s genes can produce behaviors that enable it to modify its own environment in an adaptive way.

The classic example is beavers building dams: one could consider the dam as an aspect of the beaver’s “phenotype” (traits produced by beaver genes) in much the same way as evolution produces the beaver’s teeth and tail.  The same is true for parasites that affect the behavior of their host in adaptive way (as in the parasitic nematodes that propagate their own survival by turning their ant hosts into mock “berries”, changing the color of their black abdomens to red, making the ants raise them into the air, and weakening the connection between the abdomen and the rest of the body, all of which attracts sharp-sighted birds that spread the nematodes through their droppings).  What you see below is the extended phenotype of the nematode worm:

Fig. 1.  The ant Cephalotes atratus: uninfected (top), and infected with the nematodes (bottom)

Here’s the world’s largest extended animal phenotype: a beaver dam in Alberta that is 850 m long (2790 feet). It was discovered using Google Earth, and can be seen from space (click to enlarge):

Fig. 2.  A huge extended phenotype

The point is that genes can affect behavior, and that behavior can modify the environment in an adaptive way, whether the environment be a river surrounded by gnaw-able trees or a host that can be manipulated by parasites. (Much of Darwinian medicine, by the way, involves the idea that infectious organisms cause symptoms that help them propagate themselves:  cold viruses don’t debilitate us, but allow us to remain ambulatory so that we can sneeze, shake hands, and spread the virus, while malaria protists make us prostrate during bouts of fever, rendering us susceptible to the bites of mosquitoes who carry the vector).

Anyway, when trying to explain how “extended phenotypes” evolve, Brown ties himself up in a tangle of thought and language that completely confuses the reader:

The Extended Phenotype, however, is still worth thinking about. The idea that genes are selected because of their effects outside the body that carries them was, so far as I know, first made explicit by Dawkins, and really does make you look at the world another way. But where does it get us?

There are at least three situations in which you can talk about an extended phenotype. One is niche construction, where an animal changes the world around it to suit its purposes: birds make nests, beavers make dams, caddis larvaemake houses. To the extent that these processes are under genetic control, Dawkins can talk about these changes outside the animal as a product of its genes.

The second is seen in parasites and predators. There are all sorts of ways in which parasites and predators generally modify the behaviour of their victim species. These can be dramatic, like those parasites that lead infected ants to climb to the tops of blades of grass so that they can more easily be eaten by sheep, or almost undetectable, like the way in which mosquitoes manufacture proteins that stop mammalian blood from clotting while they drink it. Again, here, a gene is clearly being selected for its effects outside the body that carries it.

So far, so good.  But then he goes a bit off the rails:

Then there is the very interesting case of domesticated plants. These are spread around the world by humans, who breed them selectively. In the case of tobacco plants, or opium poppies, we’re breeding for the effects on our brain.

This is not a case of an extended phenotype evolving genetically in humans: it is a cultural practice favored for its usefulness.  We haven’t evolved genetic tendencies to spread or breed domesticated plants—that happened only in the last ten thousand years or so, and that’s not long enough for genes favoring a tendency to domesticate plants to spread in the human genome.  This is purely a cultural practice that’s a byproduct of our big brains. The modified plants may be seen as a “cultural extended phenotype,” but that’s just confusing.

But Brown is way off the mark when trying to explain how extended phenotypes evolve.  Really, the idea is simple: any gene will be favored if it causes a behavioral change that, by modifying the individual’s environment, gives that gene a replication advantage over other genes.  Pretty easy to envision.  And of course once the environment is modified, that sets up new selective pressures that weren’t present before. Once beavers evolved the ability to build dams, then their young are now exposed to a new environment—a cozy den inside the dam—that would favor all kinds of other behaviors, like modification of parental care, the cacheing of food in the lodges, genes favoring repair of dams when they’re damaged, and so on.

But Brown makes a mess of it:

So all these are examples of extended phenotypes, in which a gene carried in one body is transmitted as a result of its effects on another.

But where in this circuit is causation? Is it more useful to think of the gene as reaching out to change the world around its organism, or to consider the environment reaching inside to change the gene? It seems to me that causation goes very clearly in the second direction and that this is true all the way down to the DNA. After all, it is the cellular mechanisms that determine both which genes are expressed, and which bits of DNA constitute a gene.

The second alternative—the one favored by Brown—simply makes no sense.  The environment doesn’t reach inside the organism to change the gene, for what we’re trying to explain is how a genetic change alters the organism’s environment. The environment is not, in such a case, a passive interactor that forces genetic change.  True, the genetic changes must take place in a certain environment, but if one has to choose either of these explanations, I’d favor the first.

But in fact neither encompass the whole situation, for it’s the interaction between genes and the environment that favors the evolution of extended phenotypes.  Rodents able to cut down trees to build protective dens for their young were favored, but that depends both on genetic variation for tree-cutting and den-building and on a pre-existing environment that contains running water and trees.  The behavior is caused by changes in the proportion of the replicators (“alleles”, the different forms of genes), but the advantage of one allele over another depends completely on the environment in which the gene finds itself.  One needn’t choose between the primacy of gene or environment (except insofar as how the behavior is inherited): both are needed to explain the evolution of “extended phenotypes.” Brown is raising a false dichotomy and confusing the reader.

He goes on:

Even if we abstract away from the sequence, as theoretical biologists do, and consider abstract genes “for” or “against” particular behaviours it is still the concrete details of the environment that constitute the selection pressure on a gene.

Mostly true, though of course there are “internal” selective pressures as well, like the effects of a gene on embryology, physiology, and so on.

And it is selection that is the active process, not simple replication.

False. Replication of different forms of genes is also “active”, and that is what causes the extended phenotype to evolve.  In fact, in terms of things actually doing something, replication is active while the environment is passive.  And he hasn’t considered another “active” process: the mutations that produce behaviors that lead to “extended phenotypes.”

DNA sets boundaries to what the environment can achieve – you can select all you like, but you’ll never breed ravens to fly under water

Hold on!  Isn’t that what penguins do?

Fig.3.  Birds (descended from flying birds) flying underwater

– but these constraints are the outer limits of what is possible. They don’t help much to predict what’s inside them. If you start with a wholly gene-centric model and think it carefully through, you can find you have reached a gene-peripheral one instead.

That’s such a poor piece of writing that I can’t figure out what it means. If he’s saying that organisms can only evolve within the limits of what’s genetically possible, then that’s obviously true. But we don’t know what is genetically possible: think of all the improbable species (like frogs and penguins) that one might not have though a priori possible.  But of course genes don’t predict evolution alone, because that depends on an interaction between genetic variation and environments.  But that’s obvious as well.  What he’s saying in this faux-clever language remains obscure.

Why does the Guardian retain Andrew Brown? Many have suggested it’s because his ideas are so muddled, yet expressed so forcefully, that he brings the paper lots of traffic in the form of angry readers. It’s as good a theory as any.  But what ticks me off the most is when he muddles biology.

56 thoughts on “Time to put Andrew Brown to pasture

  1. Question re:

    “Here’s the world’s largest extended animal phenotype…”

    : Does a coral reef not count as an extended animal phenotype [the individual Polyps being animals]?

    1. Oops Should have written this as well: I’m suggesting some coral reefs are bigger than that beaver dam.

      1. maybe, but isn’t a coral reef more like a forest?

        A beaver dam’s primary effect is to modify the environment; to change a stream into a pond. It doesn’t serve the beaver in any other way. It’s not a lodging even.

        a coral reef is simply the concatenation of a bunch of houses for small animals; it doesn’t really function so much to affect the environment around it, as it does just to act as protection from it.

        In fact, if we look at the variety of coral species, we see huge variability in the shape of the resulting coral support structures.

        if the idea were to say, permanently manipulate water flow, I don’t think there would be such large and random variation in the structures themselves.

        So, while there IS obviously an effect on the environment of reefs themselves, unlike dams, I do not think that the effect itself here is what is being selected for.

        so, not really a good example of an extended phenotype, IMO.

        1. Quoting from Extended Phenotype – But Not Too Extended. A Reply
          to Laland, Turner and Jablonka
          by RICHARD DAWKINS University Museum of Natural History, University of Oxford [2004]

          …A desert is colonised by weeds, which then change conditions sufficiently to allow the subsequent invasion by an orderly succession of plants and animals, each wave altering niches in ways that favour the next wave, culminating in a climax forest. But, important and repeatable as ecological succession is, it is not a Darwinian adaptation on the part of prior member of the succession on behalf of later members. Rather, natural selection within the gene pools of later members of the succession favours those individuals that take advantage of the conditions inadvertently set up by earlier members. The climax forest is a consequence of colonisation by weeds decades or even centuries earlier. The forest is not an extended phenotype of the weeds’ genes, nor is it helpful or illuminating to call it a niche constructed by the weeds. The same can be said of the repeatably regular pattern of development of coral reefs, in which generations of polyps build literally on the environment provided by centuries of dead predecessors, and form the foundation – literally and metaphorically – for the marine equivalent of a climax forest community

  2. there are “internal” selective pressures as well, like the effects of a gene on embryology, physiology, and so on.

    Have you seen the recent paper arguing that much of eukaryote biology is governed by the matches and mismatches between nuclear and mitochodrial genomes? Very cool, far-reaching stuff. I learned about it from Ed Yong. [link to original article therein]

    1. And since this is Jerry Coyne’s website, I should probably mention that there are direct applications to allopatric speciation and reproductive isolation mechanisms.

  3. What do you expect Jerry? You’re a world class biologist who’s specialties include speciation and ecological and evolutionary genetics! LOL :p

  4. Yes – totally baffled by that last sentence.

    On beavers, I am guessing that an ancestral rodent must have had sociality in its behaviour so that the dam building is possibly a variaton on a theme say of the tunnel building in prairie dogs – anyone know?

  5. Hear, hear. The Guardian seem to be ok with employing a troll, I’m just not sure if it’s intentional on his part or if he is just a blithering idiot. If it is the former then he does a very good impression of the latter.
    (I’m not too comfortable speaking harshly about people generally but I really can’t stand the man’s writing!)

  6. “(as in the parasites fungi that propagate their own survival by turning their ant hosts into zombies that climb onto trees, die, and then resemble red berries that are eaten by sharp-sighted birds).”

    These are separate cases. Ophiocordyceps infect camponotus ants and after they climb into a leaf of a tree and die, a fruiting body emerges and shoots out spores. On the other hand a nematode of some sort infects Cephalotes atratus and turns their gasters red to mimic fruit for birds.

  7. ” genes favoring repair of dams when they’re damaged, and so on.”

    Actually you don’t need extra genes to do this. Beavers have the ability to build dams by having evolved a simple reaction to the sound of running water. If a beaver hears it, he will drag sticks over to it. You can play back a recording of the sound of running water and a beaver will pile sticks on top of the speaker.

    That’s it. To a beaver, the genetic instruction is very simple. Wander around minding your business until you come across a small rivulet making gurgling sounds. Find some sticks and stuff them into the source of the noise . The water runs around the obstacle, moving the source of the sound, so put sticks there, repeat as often as necessary. If the resulting dam gets damaged the sound of the water flowing through the damage will produce a repairing behaviour.

    It doesn’t require a complex series of separate adaptations for this to evolve. Beavers eat sticks. They get their protection from being in water. If an eobeaver carries a stick downstream but is blocked by a natural obstruction in the stream, say a bunch of other sticks that had floated there and got stuck, he would have a hard time getting around it. Beavers are streamlined, beavers with sticks in their mouths are not. So he abandons the stick and goes back upstream to get another one.
    Now, not having the brainpower to learn from his first mistick, he encounters the same obstacle. The resulting blockage would mean more water behind it and more safety for the beaver. So, more reproductive success.

    1. I thought I read somewhere* that beavers still exhibited dam-building behaviors (like piling up objects) even if they were kept in areas without access to running water their entire lives.

      *Climbing Mt Improbable and The River Out Of Eden both seem likely candidates, since I recently read both but own a copy of neither.

  8. It’s still the case that anyone can have an opinion about anything, including Andrew Brown.

    But in perusing Brown’s “full profile” (one assumes that Brown wrote the profile himself), I can’t find a single sentence in it that qualifies Brown’s opinion on this topic as of more value than Ozzie Osborne’s.

    Here’s the “full profile”:

    “Andrew Brown works for the Guardian these days, writing long profiles for their Saturday review section and a weekly web column, Worm’s Eye View, for guardian.co.uk, as well as leaders, book reviews, features and short cuts. He also writes and presents Analysis programs for BBC Radio 4. In the time left over he writes pop science books, short stories, and other things that catch his imagination. His most recent book, a history of c. elegans, was published in Feburary 2003 in the UK by Simon and Schuster and in the autumn of 2003 in the US by Columbia University Press.”

      1. Ozzie would have the sense to know when he’s in over his head and admit he had no idea. Pity others are less self-aware.

  9. When you say “the idea of memes has not been fruitful”, I gather that you’re not criticizing the invention of the word or disputing that it describes a real, observable, phenomenon. After reading the linked book review, my impression is that you really mean the idea of “memetics”, or “the possibility that the meme might one day be developed into a proper hypothesis of the human mind”, has not been fruitful. Is that correct?

    1. I haven’t read the book in question, but from that review it seems to me it’s about 2 steps away from being Scientology. “Selfplex” is not a serious, acacdemic-sounding word, if you ask me.

      I do personally think the concept of memes is useful in conversation, at least, as a description of a particular thing. Whether it is actually anything other than a sometimes-useful abstraction for the absorption of particular ideas and patterns of behavior? I don’t know. I certainly would be suspicious of attempts to link memes to anything measurable like brain size.

    2. I have found the idea of memes very useful, as a way of thinking about the evolution of language, for example, or the persistence of a foolish, ingrained custom.

      Certainly the boundaries of a meme and a memeplex are somewhat blurry, but then, so are those of a species.

      I have long felt that Susan Blackmore missed the jump by naming her book “The Meme Machine” and not “The Selfish Meme”.

      1. Sorry, I hadn’t read your review before I posted that.

        “Blackmore’s enterprise has two fatal flaws. First, she has got the chain of causation backwards. The claim that memes created major
        features of humanity is equivalent to the
        claim that the main force driving the development of better computers has been the
        self-propagation of software. In reality,
        computers are usually designed for speed
        and capacity, which then permits the development of new software.”

        Equally, it is the bigger and more complex software, especially of games like World of Warcraft, that has driven the growth in speed and capacity of computers. Granted the big difference of human intention in the first case but not the second, this seems very parallel to the co-evolution of memes and brains.

        And it doesn’t seem self-evident to me that memeless organisms do have consciousness, or that qualities of the memes themselves that add to their transmissibility (“glibness” if you like) may not make them spread regardless of, or even contrary to, their value to us.

        1. Software development drives hardware development, just as memes drove the expansion of the human mind.

          The latter is a concept that has subsequently been embraced by academia, under the name of “the cultural brain hypothesis”. It now looks as though Blackmore was probably correct on this particular issue.

  10. I think you have misunderstood Brown’s comment about tobacco plants and opium poppies. He is not talking about human genes here. He means that one of the effects of tobacco and poppy genes is the breeding behaviour of humans.

      1. you know, at first that sounded silly to me, but really, if it’s accurate to say that we plant tobacco because it has a pleasing narcotic effect, then it has to be equally true that we plant corn and wheat because they give sustenance itself.

        In short, I don’t agree with the synthesis of Michale Pollan, especially for humans, that really haven’t existed in any numbers for more than a few tens of thousands of years.

        no, it’s much more likely that a slight narcotic effect is really indicative of a defensive reaction to be eaten to begin with by say, insects, where it is actually more toxic.

        Then humans, realizing they get a slight buzz, will tend to artificially select the plants to concentrate the effect.

        I think Pollan is looking at this backwards myself.

        1. Aren’t all new adaptations simply co-opted from previous adaptations? The narcotic effects of tobacco and poppy plants were adaptive in preventing herbivores from eating them, but have now somewhat adopted an additional adaptive advantage in that they are the primary reason these plants are cultivated by humans. As Darwin himself noted, the actions of humanity as a selective pressure are not essentially distinct from other “natural” pressures, from the perspective of the plant.

          1. No, because the cultivation of the plants in this sense has been artificial selection for concentrating the narcotic effect.

            it indeed would be like saying the fact that we breed domestic cattle is somehow of genetic benefit to Aurochs.

            or how about breeding chihuahuas as of benefit to wolves?

            1. Yes, it is artificial selection, but from the perspective of the plants which are being propagated, the character trait that produces the narcotic effect is giving them an advantage over the individuals which produce less of the substance. Selection is still selection, whether its artificial or natural, especially from the perspective of the organism on which selection acts. Think of the vastly larger number of maize plants there are in the world than teosinte plants; they’re clearly more successful than their ancestors because of artificial selection and cultivation by humans. Just as teosinte wouldn’t last long in a crop field without heavy modification, maize wouldn’t be as successful in the wilds of Mexico as its ancestor.

              I agree that selection acts upon individuals and not species. Breeding chihuahuas is beneficial only to chihuahuas in the genetic sense. But, if humans wish to artificially select for chihuahua phenotypes for their own purposes, what REALLY distinguishes this type of selection from the selection pressures that produced the wolves themselves? To say that they are somehow fundamentally different, I think, downplays the importance of artificial selection experiments throughout the last century on model organisms like Drosophila.

        2. In fact, nicotine (sulfate form) was even used as an insecticide for many years (banned now because of potential issues with contamination of produce).

  11. Beavers have an instinctual drive to build damns across flowing streams. This activity will form a pond in which the beaver can build a lodge and get on with life. I wonder, if a beaver found a suitable pond, with suitable food sources close by, would it build the lodge and stay. Or, is the instinct so strong that the beaver will keep searching for flowing water. If so, would this be non-adaptive?

  12. JAC: “the writing is so absolutely dreadful that it’s hard to believe that someone pays him for his prose”

    Indeed. Speaking as someone who has pitched a number of articles to the Grauniad, always without success, I find this fact particularly galling.

  13. From the poetic “man can embody truth when he cannot rationally know it” the author stretches this to a criticism of analytic philosophy as “disembodied model of knowing”? This is once again a defense of religion as an alternative method of knowing. So, what do you know from religion, and shall we put it to the test and verify its veracity? Ah, but a further dodge: that religion is actually not “primarily a matter of propositional beliefs”? Well, there had better be something else that is primary, because all those propositional beliefs are unfortunately demonstrably false or undemonstrable as true. So what is primary? Ritual. Religion is really just ritual. Creationism in school, gay hatred, anti-abortion hysteria? Just ritual. You can’t challenge it, it’s just ritual.

    This is what is has come down to. If you can’t defend the truth of your propositional beliefs, claim them as metaphors. Or better yet, claim them as not even important.

      1. This is once again a defense of religion as an alternative method of knowing.

        Yup. I read it during lunch. The last sentence was the whopper. Something about evolutionary theorists failing to understand how religion is practiced in faith communities.

        Vernon barely disguises the accomodationism (not sure what his own views are, but this piece is absolutely accomodationist).

  14. Andrew Brown writes as I would expect a certain D. Markuze to write if he’d only take his medications …

    1. yeah, the minute Andrew uses the line:


      …then I’ll think it’s really time he sought assistance.


  15. What happened to Brown is very typical of all writers, when your momentum is building, you got carried away by your own prose, you no longer control the chariot, the horses pull you.

    In case of fictions (like Rowling in HP) this is good, actually gives you a warm feeling of doing well. I just write, it comes out automatically (this is coincidentally what moslems believe how the Koran was written).

    In case on nonfiction, unfortunately, it shows your skills as a chariot-driver, er – your knowledge on the subject (and your own tendencies to be emotional / arbitrary, of course).

    That’s why we need an editor, or even just a walk in woods, or a relaxation with classical music once a while.

    Brown missed these fine points. But I agree with Jerry, it is the Guardian that are more at fault (I would say Brown is good with the writing fee he received .., man had to do ..).

    There are alternative explanations of course. What if there are some sinister ideological reasons to commit these foolishness? They actually get precisely where they aim for. In this case, writing / publishing pseudo scientific papers to boost one’s street cred or to push anti-science agenda through misleading articles? I.e. religious agendas?

    (I run into same problem as Brown here, so I’d better stop) 😀

    1. (I run into same problem as Brown here, so I’d better stop) 😀

      No you didn’t. The driver of your chariot isn’t asleep at the reins…

      1. What I meant is that my chariot seems starting to wiggle into things I may not have hard evidence on … of course it is not even a shaking yet. 😉

  16. Brown specializes in being annoying, he’s quite the expert you know, and I wouldn’t threaten his authority in being annoying if I were you. Unless of course you want five times the internet traffic.

  17. Doesn’t The Guardian have editors any more?

    If you were going to get someone to write about biology for a major publication, shouldn’t you get someone with some qualifications or otherwise displaying a strong knowledge of the subject?

  18. Articles like Brown’s are popular, as they purport to refute Dawkins on his home turf. Dawkins has clearly rattled many Christians, and so diatribes whining about his supposed ignorance of religion are very popular. Some of these like to go further, and claim that his biology is also wrong. Such articles are usually incompetent drivel, but they are loved by certain Christians, who get a rare taste of perceived intellectual superiority.

    Needless to say, these people infest the article comments. “WestTexan” takes arrogant stupidity to barely conceivable heights.

  19. Some animals might have evolved to be tasty to humans. As long as we eat them after they have reproduced (or we keep genetically close relatives which can reproduce), the individual’s timely death is the key to the survival of the species.

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