Comments to “The Selfish Gene”
Warning: This is not a review of Dawkins’ work, and the reader is expected to have read the book to understand the discussion, or at least to be familiar with the ideas exposed therein.
A good book is one with great ideas in it. A great book is one which induces you to develop good ideas. This is a great book. It explains clearly the main questions and proposals of neo-Darwinism in a fashion which is reachable both to the layman and to the expert. Not that I agree with all the ideas exposed in the book, but it promotes the discussion and further developments against or for the ideas, encouraging the evolution of those memes, we could say. Many of the ideas presented here are a continuation or an argument against those of the book, but others are not much related, although inspired by it. Another thing is that I don’t tend to repeat the ideas I agree with, so probably this will seem overcritical.
To my view, the main effort of the book is to defend the gene as a unit of selection. No one bothers to argue anymore about Darwinism or evolution, this is generally accepted. The discussion, at least in the days the book was written, was at which level evolution acts: Genes? Individuals? Groups? Ecosystems? Well, this very question poses philosophical difficulties, which we should cover first.
We can make a distinction between absolute and relative beings (Gershenson, 2002). Absolute being (abs-being) is independent of the observer. It is unlimited, because we can always describe more and more properties of something. Relative being (rel-being) is dependent of an observer (or cognizer), and her context. It is limited, because you can only name a finite set of properties of it. In theory, we can approach the abs-being as much as we want to, but we will never contain it completely. Different cognizers have different rel-beings for the same abs-being. In theory, different rel-beings can be very similar, so that the differences among them can be neglectible. In practice, people tend to confuse rel-being and abs-being, and believe that their rel-being IS the abs-being (i.e. the “real thing”), or at least that there is a one to one correspondence between them. With complex and contextual systems, it turns out that the differences between rel-beings do make a difference. The proposed way to follow is to accept or at least tolerate other rel-beings, since there is no predefined way of judging which is the “right” one, and I believe that in general, there can not be any “right” rel-being, since it depends on a particular context, and contexts change constantly. But for specific contexts, of course we can find rel-beings which are more useful than others, so there is no danger of radical subjectivism and “anything goes”. In science, a particular case of rel-beings are models, and abs-beings would be the modelled. So this is about not confusing the model with the modelled, the metaphor with the metaphored.
After this brief parenthesis, we can continue with the question we posed.
So, at which level evolution acts? Well, at all, of course! It seems that multi-level selection already hints at this (e.g. Michod, 1999, which I still should read...) Different levels are different rel-beings which we use to describe evolution, but they all abs-are the same thing. We could see it as different pictures of the same building, all from different perspectives. If you look only at them, and believe that the pictures are the real thing, they will be different. But if you step back and realize they are all different pictures of the same thing, you can use them to get a less-incomplete image of the building. The “right” level at which we will want to describe evolution will depend more on our personal goals and interests, but that won’t make it the “true” level on which evolution acts. After noting the difference between absolute and relative beings, it even sounds silly. Evolution does not act on our observations! Construction workers don’t build on photographic film!
In the second edition of The Selfish Gene, Dawkins is more modest about “almighty” genes. He uses the metaphor of replicators and vehicles. Genes are replicators, and bodies and groups are their vehicles to survive. But we can see individuals or groups or molecules as replicators as well, since the gene has a functional definition. In other words, when a gene is transmitted to new generations of bodies, what is transmitted is the function, since the molecules which form the genes can very well change. We could see genes as vehicles of complex molecules for replicating, but probably that would be not very useful for understanding how life came to happen. Individuals could also be seen also as replicators, but again you cannot explain how these individuals came to happen, you have to assume this, and especially their cooperation. Indeed it seems that the gene-centred view is clearer and easier to understand for evolutionary biological purposes. But that does not make genes the centre of evolution, and I am sure Dawkins never meant that, but it seems that people might easily misunderstand this. But at the end, with the replicators-vehicles metaphor, Dawkins also admits that more than one level should be studied in order to understand evolution. You cannot understand why certain genes are selected if you do not observe their phenotypical and extended phenotypical effects...
Yes, you can try to describe everything in terms of genes, but their survival depends on the fitnesses at different levels. You can call them replicators or vehicles, but you need all the fitnesses, and multilevel selection allows you to study that. The system is selected by the overall fitness of al the level-fitnesses. Genes selected in cells, in bodies, in societies, in ecosystems. If you screw up at one level, you screw up in all: levels are different perspectives of what the systems abs-is. If you perceive at least one bad rel-being, the abs-being is spoiled, even if you cannot notice it at other levels. If you take several pictures of a building, and it is damaged only in few or one of them, the building itself is damaged, no matter how nice are the other pictures (unless the damaged picture is fuzzy and out of focus?).
For choosing which level might be more useful to describe evolution we should also take into account the time-scale we want to observe: short-individual, medium-species, long-gene, very long-molecule...
But in any case, evolution acts at all levels. How we describe this, is another issue. I agree with Dawkins that a gene-centred view seems the most appropriate for understanding and studying biological evolution, but this does not mean that the only nor main driving force of evolution occurs at that level.
If genes are selected for their co-organization (how they work together), wouldn’t also individuals? And groups? And ecosystems? This would force transitions between parasitism or free-riding towards symbiosis or synergy, and not the other way around. Of course new free-riding possibilities are developing every moment, but there will be a higher probability to reach a behaviour beneficial to the system than the opposite. This has a flavour of self-organization (Gershenson and Heylighen, 2003), since the probability distribution is not doubly stochastic. This means that synergy is “preferred” when you have free riding around. But on the other hand, if you have new free riding possibilities, these will have a higher probability to spread, but not if they are too nasty. This interplay favours evolution.
First of all, we can distinguish self-organization in two types of populations: “homogeneous” and “specialised”.
Homogeneous populations consist of similar agents, i.e. which have similar functions/structures. In many cases, they tend to conform: by imitation, empathy, or propagation. We can say that they share control of the population in a distributed way through conformity. This suppresses free-riding, in two ways: First, neighbours induce conformity, so that it is harder that someone will try to cheat, since the others induce her to conform. Second, if an agent succeeds into free-riding, this is contagiated, everyone turning into free-riders, and in the short term, it is not beneficial even for the selfish agent... This is similar to a tit-for-tat strategy...
In a specialised population, we have diversity: each agent can have different roles. Through evolution, we would expect that parasitism would tend to symbiosis, since it is not good for the parasite to exploit too much the host... this has been also called “prudent predation”. I think that free riding is not “bad”, it is just a property in the stages of evolution which has been anthropomorphized too much... Also some behaviour could be seen as selfish from one perspective, and not so much from another... selfishness is partially relative to the observer.
Now, a population could be seen both as homogeneous and specialised, depending on which aspect systems (ten Haaf et al., 2002, ch 3) we focus on. For example, different agents can have the same structure or rules(e.g. DNA), but behave in different ways, or have different roles, due to their context... Here we have to notice that the same system can behave in different ways in different contexts...
We can say that in nature, evolution at each stage needs to be opportunist enough to explore as many possibilities for evolving. This could be through random fluctuations. On one hand, it can promote free-riding, and anti-free-riding mechanisms, since agents should take every opportunity to take advantage of others, and not to let others to take advantage of them. This overlaps with diversity, or specialisation. Diversity reduces competition, and is a step towards cooperation and integration at a higher level...
Another thing we should observe is that the environment in many cases also suppresses free riding, and promotes synergy. Francis Heylighen told me the following example: at roads you have lines painted indicating where cars should go, but then free riders would not follow those lines in order to go faster, and obstruct the traffic. If there are barriers between lanes, free-riders just can't change lanes. So in some cases, the interplay between organisms and their environment can also promote synergy, moreover when agents change their environment... (Wright, 2000) There is no free riding if there is no opportunity for it, and in many cases the environment constrains these opportunities. This is very much the case for humans, our social and cultural environment suppresses free-riding temptations... In an ideal world, if there would be no detectors and cameras at stores, no one would be tempted to shoplift, but the fact is that detectors, reduce the free riding temptation, since almost surely you would be caught... and that would not pay off...
I just want to repeat that free riding should not be seen as a problem. It is an aspect of evolution, since actually it promotes it. I cannot imagine evolution without free riding, so it would be silly and futile to try to avoid all possible new free-riding (although it is not a reason for trying to avoid as much as we can, I am arguing against absolute no free riding in any aspect, not promoting to abuse your fellow). You just can’t. Of course the other side of evolution is fighting the free riding, but that’s what evolution is all about: struggle. Everyone trying to free ride everyone else without everyone else free riding them.
I just read a very interesting article by Eshel Ben-Jacob (2003) and combined with recent readings, some ideas were developed.
What I found of most interest in Ben-Jacob’s paper, is that more complex bacterial colonies are more adaptive and endurable. This can explain evolution of complexity at this level, since the more complex a colony of bacteria is, it is fitter to survive in unpredictable environments (in regulated environments actually they “loose” complexity, and “gain” faster and more efficient propagation for their limited condition, but of course if you take that strain out again into the wild, they cannot adapt as much as the “wild” strain).
This is related to Ashby's law of requisite variety: a system needs variety to survive/adapt to the variety of its environment. In this case we could replace variety for complexity. But! since the environment of a system is composed of other systems, when a system increases its complexity to cope better with its environment, it also increases the complexity of the environment of all its fellow systems. (In most cases when people study systems, if they take into account their environment, they forget that that is also a system). Therefore, from Darwinian
principles, you have co-evolution of complexity without a choice! Every system tries to be more complex through natural selection, making the environment of other systems more complex, which will try to become more complex. It looks a bit like a circular tautology, but I believe it makes sense.
Ben-Jacob describes how bacteria can self-complexify themselves in order to cope better with the environment, but I believe this could be extended to all levels...
Well, I suppose many other people have said similar things with other words in other contexts, but anyway I believe it is interesting.
● The experiment of cutting rat’s tails does not prove that genes don’t change in a lifetime, since you cut the tail, but don’t do anything to the genome. Could genes mutate, change activation, or in any case change a bit? Well, they do for example after a viral or bacterial infection which inserts DNA in the cells. A proposed experiment, related to metabolism. Train rats (clones) exercising them so that they become fit. Have a control set of lazy fat rats (clones of the same rat). Wait a few generations of the same, and see if descendants the exercised set are naturally fitter (without training) than the lazy ones. Well, probably there wouldn’t be a direct change in the genome of each rat, but there would be a pressure on the fit set which is absent in the lazy one. So rats with fit mutations would have higher chances of spreading their genes, since rats with unfit mutations would die earlier. In the lazy group, since there is no pressure, the rats with unfit mutations could survive and reproduce as well as the others. Is all the information passed down to the zygote only DNA, or is there also some in the proteome? Probably the genome does not change, but the proteome surely can change. And how much does the genome control the proteome, and not vice versa? Note (2004-03-16): I thank Andrei Kouznetsov for making me realize my confusion. The genes shouldn't change fast, it is their expression which can change easily. What I wanted to note is that probably not all the information lies in the genome, but I was mistaken that the proposed experiment might change the genome of rats... it could only change its expression...
● Aging and sexual reproduction arise because they facilitate evolvability. Genes which cannot evolve (adapt) will not survive harsh changes in the environment as those which can.
● Genes are also quantum-like. For example, a cell has the potentiality to develop skin cancer, but the environment (context) determines if it will develop or not.
○ Contextuality - dependance of a system of its environment for predicting the behaviour of the system.
● Not every gene is “good” in a population, in the sense that in many cases diversity is stimulated as opposed to “fitter” or “stronger” individuals. If all individuals specialize towards one goal, the population will have a lower “group fitness” than a diverse group. For example, if there were only alfa males in a chimp group, noone would be able to have other males to dominate. Of course natural selection takes care that there is such a diversity, but what I want to say is that this selection is actually favouring that there will be some “weak” individuals. This is very clear in non-reproductive insect castes. And actually, there the diversity is not at a gene level, but more at an individual level (a bee will develop into a queen if it is fed with royal jelly, but has the same genes as other bees).
Ben-Jacob, E. (2003). Bacterial Self-Organization: Co-Enhancement of Complexification and Adaptability in a Dynamic Environment, Phil. Tran. R. Soc. Lond. A 361,pp. 1283-1313.
Dawkins, R. (1989). The Selfish Gene, New Edition. Oxford University Press.
Gershenson, C. (2002). Complex Philosophy. Proceedings of the 1 st Biennial Seminar on Philosophical, Methodological & Epistemological Implications of Complexity Theory. La Habana, Cuba. Also in InterJournal of Complex Systems, 544.
Gershenson, C. and F. Heylighen (2003). When Can we Call a System Self-organizing? To be published in Proceedings of ECAL 2003: 7th European Conference on Artificial Life. Dortmund, Germany.
Michod, R. E. (1999). Darwinian Dynamics, Evolutionary Transitions in Fitness and Individuality. Princeton Univ. Press.
ten Haaf, W., H. Bikker, and D. J. Adriaanse (2002). Fundamentals of Business Engineering and Management, A Systems Approach to People and Organisations, Delft University Press
Wright, R. (2000). Non-Zero. The Logic of Human Destiny. Pantheon Books.