Interesting theory, but wrong. In fact, the right answer is well known, and does not involve memes at all.
The reason why it's equally good for the genes to produce a male or a female, and why there's an equal number of males and females in almost all animal species, is that the expected number of offspring for a male and a female is equal. It has to be that way, because everybody has exactly one father and one mother.
While it might be true that 8/10 of females and 4/10 of males of a given species reproduce, the males reproduce more when they do. A smaller probability of a higher number will give you the same expected value.
I think this argument (among many others) is nicely explained in the Selfish Gene by Dawkins.
The reason why it's equally good for the genes to produce a male or a female, and why there's an equal number of males and females in almost all animal species, is that the expected number of offspring for a male and a female is equal. It has to be that way, because everybody has exactly one father and one mother.
While it might be true that 8/10 of females and 4/10 of males of a given species reproduce, the males reproduce more when they do. A smaller probability of a higher number will give you the same expected value.
I think this argument (among many others) is nicely explained in the Selfish Gene by Dawkins.