Fifty years old this year, this masterclass on the role of the gene in Darwinian evolution is a classic not just because of the eye-opening revelations of its arguments but also because they are clearly explained in easy-to-read and engaging prose.
Dawkins thesis is that organisms - you and me, all other animals, including insects, plants and fungi and bacteria, all living things - are 'survival machines' for more-or-less immortal 'replicators' (genes). He suggests that once upon a time there were chemicals in a soup. Some were more stable than others. And just like crystals form by atoms joining together at the behest of their chemistry, so 'replicators' formed at the behest of theirs, but these didn't simply accumulate but formed and then split so their numbers increased. The most successful (those that lasted longest, or replicated fastest, or had greatest copying-fidelity) increased in number at the expense of the least successful. Then some developed protective protein sheaths and became cells.
These genes are the only thing about you that is more or less immortal; some of them have been going for millions of years, swapping from one body to another. Many of them collaborate to develop embryos and bodies and continue to collaborate as all your cells work together to keep you alive; they collaborate because their only path to immortality is through your sperm or eggs. Other genes (eg those in bacterial infections) don't collaborate because they can hop from body to body in other ways (sneezes, touches etc) so they don't have to wait for the host to reproduce. Still other genes may be parasitic: much of your DNA is 'junk' but it still gets replicated.
He goes on to explain things such as altruism (an evolutionary successful strategy if the genes of a lot of your relatives are preserved through your self-sacrifice) and how an evolutionary stable strategy can lead to a population of mixed doves and hawks (too many hawks would kill one another while a population of mostly doves would be easily exploited by a few rogue hawks). He shows why parents might kill off their own runt children in order that more of their children survive and why fathers are more likely to leave their children than mothers are (and the advantages for a female in playing hard to get).
He also introduces the idea of memes and points out that a successful meme might be a more likely path to immortality than a gene.
I found this book enlightening and very easy to read. I'm sure that some of the science has dated (and I would recommend reading about epigenetics in How Life Works by Phillip Ball) but it is still eye-opening and educational. A classic!
Selected quotes:
- “We, and all other animals, are machines created by our genes. Like successful Chicago gangsters, our genes have survived, in some cases for millions of years, in a highly competitive world.” (Ch 1)
- “I know I am in danger of being misunderstood by those people, all too numerous, who cannot distinguish a statement of belief in what is the case from an advocacy of what ought to be the case. ... unfortunately, however much we may deplore something, it does not stop it being true.” (Ch 1)
- “Before the coming of life on Earth, some rudimentary evolution of molecules could have occurred by ordinary processes of physics and chemistry.” (Ch 2)
- “No matter how much knowledge and wisdom you acquire during your life, not one jot will be passed on to your children by genetic means.” (Ch 3)
- “Individuals are not stable things, they are fleeting. Chromosomes too are shuffled into oblivion, like hands of cards soon after they are dealt. But the cards themselves survive the shuffling. The cards are the genes.” (Ch 3)
- "The gene is the basic unit of selfishness.” (Ch 3)
- “A caterpillar and the butterfly it turns into have exactly the same set of genes.” (Ch 3)
- “It is often possible to picture males as high-stakes, high-risk gamblers and females as safe investors.” (Ch 4)
- “All animal communication contains an element of deception right from the start, because all animal interactions involve at least some conflict of interest.” (Ch 4)
- “To a blackbird, a mole may be a competitor, but it is not nearly so important a competitor as another blackbird.” (Ch 5
- “It is a simple logical truth that, short of mass immigration into space. with rockets taking off at the rate of several million per second, uncontrolled birth rates are bound to lead to horribly increased death rates.” (Ch 7)
- “Contraception is sometimes attacked as ‘unnatural’. So it is, very unnatural. The trouble is, so is the welfare state. I think that most of us believe the welfare state is highly desirable. But you cannot have an unnatural welfare state, unless you also have a natural birth control; otherwise, the end result will be misery even greater than that which obtains in nature. The welfare state is perhaps the greatest altruistic system the animal kingdom has ever known. But any altruistic system is inherently unstable, because it is open to abuse by selfish individuals, ready to exploit it.” (Ch 7)
- “When lemmings flood in their millions away from the centre of a population explosion, they are not doing it in order to reduce the density of the area they leave behind! They are seeking, every selfish one of them, a less crowded place in which to live.” (Ch 7)
- “There is bound to be variation in the population of males in their predisposition to be faithful husbands. If females could recognize such qualities in advance, they could benefit themselves by choosing males possessing them. One way for a female to do this is to play hard to get for a long time ... Any male who is not patient enough to wait until the female eventually consents to copulate is not likely to be a good bet as a faithful husband.” (Ch 9)
- “Language seems to ‘evolve’ by non-genetic means, and at a rate which is orders of magnitude faster than genetic evolution.” (Ch 11)
- “When you plant a fertile meme in my mind you literally parasitize my brain, turning it into a vehicle for the meme’s propagation.” (Ch 11)
- “When we die there are two things we can leave behind us: genes and memes. ...But as each generation passes, the contribution of your genes is halved. It does not take long to reach negligible proportions ... We should not seek immortality in reproduction. But if you contribute to the world's culture ... it may live on, intact, long after your genes have dissolved in the common pool. ... The meme-complexes of Socrates, Leonardo, Copernicus, and Marconi are still going strong.” (Ch 11)
- "It does not seem ever to have been satisfactory answered why the two first operational atomic bombs were used ... to destroy two cities instead of being deployed in the equivalent of spectacularly shooting out candles.” (Ch 12)
Originally published by the Oxford University Press in 1976
My 40th anniversary edition was issued in paperback by the OUP in 2016
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