Chapter Chapter-by-Chapter Anaylsis of The Selfish Gene (1989 edition) - Study Guide by Richard Dawkins

children by other sexual partners, and so propagate more of his genes. Thus, each partner tries to exploit the other and force them to invest more.

When two gametes fuse, both contribute equal numbers of genes to the new individual but the egg contributes far more in the way of food resources. Therefore, the asymmetry starts as early as conception because the mother stands to lose more if child dies than male because of this initial investment. This would mean that there is some evolutionary pressure on males to invest a little bit less in each child, and to try and have more children by different wives, if they can be sure that the wife has a reasonable chance of rearing the child on her own.

There are several options available to the female to prevent being left with the sole responsibility of the child. She could refuse to copulate. She is in demand because she supplies the large, nutritious egg and therefore a male who successfully copulates, gains a valuable food reserve for his offspring. Dawkins describes two different scenarios where "driving a hard bargain" could evolve by natural selection. The first he calls the domestic bliss strategy. This is when the female tries to spot signs of fidelity and domesticity in advance. She does this by playing hard to get for a long time so that any male who is patient enough to wait until the female consents is likely to be a good bet as a faithful husband. Courtship rituals often include considerable pre-copulation investment, such as building a nest or courtship feeding, so that the male is forced to invest so heavily before he can mate with the female so that is would no longer pay him to desert after copulation. However, this is dependent on all females playing the same game and Maynard Smith carried out a game theory test that supported the idea that coyness in the female and faithfulness in the male could be an ESS.

The second strategy Dawkins describes is the "He-man strategy". This is when the females resign themselves to getting no help from the father in rearing the children and so they go all-out for good genes, refusing to reproduce with anyone other than the best. They choose their male on evidence of ability to survive because this means that the father will be passing on genes that will benefit the survival prospects of the offspring. They may choose a mate because they have strong muscles and so can escape from predators, or they may go for sexual attractiveness which will benefit their sons when it is their time to reproduce because they will be picked by the new generation of females and consequently provide lots of grandchildren. Another theory on how females choose their mates, as proposed by Zahavi, is the Handicap principle. This is when handicaps evolve purely because they are handicaps – they indicate that the male is worthy of mating with because he can survive in spite of the handicap.

Therefore, the various different kinds of breeding systems that are found among animals can be understood in terms of conflicting interests between males and females, termed the battle of the sexes by Dawkins. Individuals of either sex "want" to maximise their total reproductive output during their lives but it is precisely this that causes the clash.

You scratch my back, I’ll ride on yours

Dawkins argues that "if animals live together in groups, their genes must get more benefit out of the association than they put in." For example, Hyenas can catch a larger prey if they hunt in a pack, spiders can build a larger communal web if they work together, and fish that swim behind another fish may gain hydrodynamic advantage. More importantly, if they are in a group they are able to take more precautions from being eaten by predators, namely by staying in the middle of the pack so that there is another individual between you and any possible hiding places for the predator.

However, bird alarms appear, at first sight, to be a genuinely altruistic behaviour because it has the effect of warning others of predators while at the same time drawing the predator’s attention to the caller. However, there are several possible "selfish" explanations. Firstly, there is a good chance that the flock contains some close relatives and so a gene for giving an alarm call can prosper in the gene pool because it has a food chance of being in the bodies of some of the individuals saved. Another possible explanation is that one bird has seen the predator while the rest of the flock has not. At this stage the predator has