The Selfish Gene (40th anniversary edition) – Richard Dawkins, 2016 (original 1976, 2nd ed. 1989)

Interestingly most of the Nature and Environment book group members didn’t care for this; none of them had read it before and most felt they didn’t have the background to make sense of it. I didn’t think I had much of a background myself, but it is a topic that’s interested me for a long time (Jacques Monod’s Chance and Necessity, one of the formative volumes of my adolescence, is kind of related, and I absolutely loved the Coursera Intro to Genetics and Evolution with Dr. Mohamed Noor – one of the best MOOCs I’ve taken.) It is true that while Dawkins is very clear in the particulars, the structure is a little lacking.

My strategy of reading all text first and then the endnotes also paid off, as the notes are very long and, as others complained, often contradict the text because they were written later.

Evolution is a theory which seems simple but which has subtle implications. I tried to explain to the group my understanding of what Dawkins was trying to say about many small gametes vs fewer larger gametes leading to the polarization of male and female sexual strategies, and how that works out differently in water than on land, but I didn’t do a very good job.

Interesting bits:

  • Queen and worker bees have differing interests—explaining why workers can and do overthrow the queen sometimes
  • Good explanation of game theory strategies, with “nice” winning over “nasty,” forgiving but not too much so—“Tit for Tat” winner described as “nice,” “forgiving,” “not envious.”
  • “Segregation distorters” (meiotic drive) that spread like wildfire throughout a population because they game the system, then force extinction.
  • Fantastic quote from Robert May: “To a good approximation, all species are insects.”
  • Thisbe irenea caterpillars summon ants through sound and control them chemically!
  • Dawkins theorizes that naked mole rats ought to have dispersing individuals as the eusocial insects do, and it looks like he was right, but not in the interesting locust-like way he speculates: “What if naked mole rats are like American grasshoppers, primed to produce a distinct, dispersing caste, but only under conditions which, for some reason, have not been realized this century?” Actually it seems to have been proven that the Rocky Mountain locust went extinct, so even that is not applicable.
  • Because this book was fresh in my mind, I was especially fascinated by the news on the marbled crayfish that clones itself.

A funny anecdote: “[The cyclic interbreeding theory] is commonly attributed to S. Bartz, who developed it seven years after Hamilton originally published it. Characteristically, Hamilton himself forgot that he had thought of the ‘Bartz theory’ first, and I had to thrust his own paper under his nose before he would believe it!”

I usually try to structure the quotes in some way, but this is another finishing-it-months-later post and these mostly stand alone so I’ll just dump them here. One more comment: we all complained about Dawkins’ huge ego and frequent sexism. Nonetheless, it’s a classic for a reason and I want to re-read it at some point. I’d love to absorb the arguments enough to successfully explain them to someone else. The ideas about evolutionary stable strategies and the math and game theory that explains them, and group vs individual vs genome vs gene unity, feel powerfully explanatory.

Quoting Robert Trivers in the intro: “…if … deceit is fundamental in animal communication, then then there must be strong selection to spot deception and this ought, in turn, to select for a degree of self-deception, rendering some facts and motives unconscious so as not to betray—by the subtle signs of self-knowledge—the deception being practiced.”

Let us try to teach generosity and altruism, because we are born selfish. Let us understand what our own selfish genes are up to, because we may then at least  have a chance to upset their designs, something that no other species has ever aspired to.

…uncles on the mother’s side should be more interested in the welfare of nephews and nieces than uncles on the father’s side, and in general should be just as altruistic as aunts are. Indeed in a society with a high degree of marital infidelity, maternal uncles should be more altruistic then ‘fathers’ since they have more confidence in their relatedness to the child.

Depending on the ecological details of the species, various mixes of caring and bearing strategies can be evolutionarily stable. The one thing that cannot be evolutionarily stable is a pure caring strategy.

When a woman reached the age when the average chance of each child reaching adulthood was just less than half the chance of each grandchild of the same age reaching adulthood, any gene for investing in grandchildren in preference to children would tend to prosper… A woman could not invest fully in her grandchildren if she went on having children of her own.  Therefore genes for becoming reproductively infertile in middle age become more numerous, since they were carried in the bodies of grandchildren whose survival was assisted by grandmotherly altruism.

Genes in juvenile bodies will be selected for their ability to outsmart parental bodies; genes in parental bodies will be selected for their ability to outsmart the young. There is no paradox in the fact that the very same genes successively occupy a juvenile body and a parental body… they will exploit their practical opportunities.

Like a fashion in women’s clothes, or in American car design, the trend toward longer [bird of paradise] tails took off and gathered its own momentum. It was stopped only when tails became so grotesquely long that their manifest disadvantages started to outweigh the advantage of sexual attractiveness.

It is even possible that man’s swollen brain, and his predisposition to reason mathematically, evolved as a mechanism of ever more devious cheating, and ever more penetrating detection of cheating in others. Money is a formal token of delayed reciprocal altruism.

What, after all, is so special about genes? The answer is that they are replicators. … If forms of life exist whose chemistry is based on silicon rather than carbon, or ammonia rather than water, … if a form of life is found that is not based on chemistry at all but on electronic reverberating circuits, will there still be any general principle that is true of all life? Obviously I do not know, but, if I had to bet, I would put my money on one fundamental principle. This is the law that all life evolves by the differential survival of replicating entities. The gene, the DNA molecule, happens to be the replicating entity that prevails on our own planet.

All that genes can really influence directly is protein synthesis. A gene’s influence upon a nervous system, or, for that matter, upon the color of an eye or the wrinkliness of a pea, is always indirect. … The caddis house is only a further extension of this kind of sequence. Stone hardness is an extended phenotypic effect of the caddis’s genes. … [T]he next step in this argument: genes in one organism can have extended phenotypic effects on the body of another organism.

To quite a large extent the interests of parasite genes and host genes may coincide. From the selfish gene point of view we can think of both fluke genes and snail genes as ‘parasites’ in the snail body. Both gain from being surrounded by the same protective shell, though they diverge from one another in the precise thickness of shell that they ‘prefer.’ This divergence arises, fundamentally, from the fact that their method of leaving this snail’s body and entering another one is different. For the snail genes the method of leaving is via snail sperms or eggs. For the fluke’s genes it is very different.

A bird may be flying home, carrying food for its own young. Suddenly, out of the corner of its eye, it sees the red super-gape of a young cuckoo, in the nest of a bird of some quite different species. It is diverted to the alien nest where it drops into the cuckoo’s mouth the food that had been destined for its own young.  … if we do assume that the cuckoo’s gape is a powerful drug-like superstimulus, it becomes very much easier to explain what is going on. It is not being stupid. ‘Fooled’ is the wrong word to use. Its nervous system is being controlled, as irresistibly as if it were a helpless drug addict…

Living things, of course, were never designed on drawing boards. But they do go back to fresh beginnings. They make a clean start in every generation. Every new organism begins as a single cell and grows anew. It inherits the ideas of ancestral design, in the form of the DNA program, but it does not inherit the physical organs of its ancestors. It does not inherit its parent’s heart and remould it into a new (and possibly improved) heart. It starts from scratch, as a single cell, and grows a new heart, using the same design program as its parent’s heart, to which improvements may be added. … One important thing about a ‘bottlenecked’ lifestyle  is that it makes possible the equivalent of going back to the drawing board.

All printed copies of this book will be the same as one another. They will be replicas but not replicators. … They do not form a lineage of copies, with some books being ancestral to others. A lineage of copies would exist if we xeroxed a page of a book, then xeroxed the xerox, then xeroxed the xerox of the xerox, and so on. In this lineage of pages, there really would be an ancestor/descendant relationship. A new blemish that showed up anywhere along the series would be shared by descendants but not ancestors. An ancestor/descendant series of this kind has the potential to evolve.

Superficially, successive generations of stick-insect bodies appear to constitute a lineage of replicas. But if you experimentally change one member of a lineage (for instance by removing a leg), the change is not passed on down the lineage. By contrast, if you experimentally change one member of the lineage of genomes (for instance by X-rays), the change will be passed on down the lineage. This, rather than the fragmenting effect of meiosis, is the fundamental reason for saying that the individual organism is not the ‘unit of selection’—not a true replicator. It is one of the most important consequences of the universally admitted fact that the ‘Lamarckian’ theory of inheritance is false.

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