Deity Delusion and Natural Selection
I suggest to read first 'Rationality, Evolution, Neanderthals, Asperger's Affinity'.
When rationality is nearly as strong as instinctivity, when rationality contributes a lot to the fitness to survive of the individual, but there is still a reluctant willingness to breed, then the deity delusion can have a big influence upon natural selection.
During all those times in prehistory and early history, when means and knowledge about contraception were lacking and attempts of abortion were often fatal, abandoning or killing newborns was a widespread practice.
A rational woman, couple, group might decide that the number of living offspring at a given moment is enough, and they would want to get rid of the next unwanted progeny. But if they have the delusion of a deity, who appears to give life as a gift, to punish for abandoning the gift, to reward for the sacrifice in the afterlife, then they fear the deity too much and keep the child instead.
The men's fear of the deity's command to procreate may have several consequences upon the fate of women. A positive effect may be, that it coerces men to provide women with the necessities of survival. But the most dire effect is probably, that it justifies men to manipulate and coerce women to have offspring. The men fear the deity's wrath, so they reduce their own fear by making the women their victims.
The force of a strong procreation instinct with little rationality without a deity delusion and the force of a procreation instinct controlled by rationality combined with the deity delusion might thus lead to an equal number of offspring. Thus at that level, they deity delusion helps to spread the genes of the more rational members of the society and thus also of those with the deity delusion.
It seems as if the entire deity delusion was a byproduct of evolution to coerce unwilling people to raise more offspring than they would want.
Only when rationality gets so strong, that it outweighs both, the procreation instinct and the deity delusion, natural selection reaches its end in producing wise rational atheistic non breeders, leading to the extinction of their highest developed rationality.
