Comment by 7952 | Hacker News Reader

Comment by 7952 | Hacker News Reader

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The main difference between male and female is cost of reproduction. Sperm is tiny and can be produced in massive quantities. Eggs are much larger and take more energy to produce. This difference is then carried into other parts of reproductive strategy. The two sexes reach a state of equilibrium with each other in terms of strategy.

Females are super careful about picking a mate because they spend months making an egg. They have a sunk cost. And females are relatively more caring about young because it is cheaper than making a new egg.

This access control forces males to evolve to be pleasing and provide some proof of quality. And this proof of quality can create more of a sunk cost for the male. They stick around and protect the young because it is easier to do that than find another female, impress them, build a nest etc.

Also, sex is very very obvious in terms of primary sexual characteristics. We have literally evolved to focus on those things. But outside of reproduction it is far less obvious in biology. On an individual level it is better to think of sex as an output rather than an input. Things don't happen because of the sex variables state, rather sexual characteristics are a consequence of other processes.

> Eggs are much larger and take more energy to produce.

>Females are super careful about picking a mate because they spend months making an egg.

The prevailing science was that females - assuming we are talking about humans - don’t make eggs rather are born with a finite number that reduces over their life time.

Only in the last couple years has the science begun to be questioned with the possibility that women do in fact make new eggs during adulthood. However, as far as I know that is still an open ended question being studied, whereas you offer some very specific facts about the required energy to produce eggs, which would suggest that in fact studies have not only confirmed women do actually make new eggs during their lifetime but there is further understanding about that process.

Could you link any studies about women producing new eggs “every couple months” and the energy required that you reference?

It is a higher cost regardless of when that cost is incurred. Although with humans I would guess that the 9 months of pregnancy and years of care is the relevant sunk cost. Compare that to the relative ease of a male who could have many offspring per year with little effort.

> Although with humans I would guess that the 9 months of pregnancy and years of care is the relevant sunk cost.

Humans are social animals with a wide variety of cultural values, in most cultures throughout history it won’t be a viable option for a man to go around impregnating multiple women every year and likely result in becoming a social outcast in civilized societies or outright killed in others.

Most cultures tend to be monogamous, courting and marriage being fairly common and also dowries were and are real thing -where a man pays a cost for each daughter to be married - not to mention co-evolution of societal norms that have also resulted in laws in some societies requiring child support until a child is 18. Whatever the natural biological costs, humans seem to have created different social norms and laws that have there own costs tending to curb the behavior you describe.

But that behaviour (monogamous, courting and marriage) can absolutely be seen as an evolutionary adaption. Male birds do not really need to help a female build a nest or look after eggs. But if they don't the female will deny access to sex, or the offspring will never hatch. And the female could just mate with any random bird, and not bother building a nest. But the egg won't survive.

The same is true of humans. If a males want their kids to survive to reproductive age then looking after their mum and the kids during infancy is the best strategy. And the best strategy for the mum is to use what power she has to encourage that. That may not be entirely a reflection of biology now, but it certainly was in the past. And it is no accident that humans find certain traits attractive in a mate.

But the difference in cost absolutely does still exist. Single parent households where the mum is left holding the baby are not exactly unusual. And the health burden of carrying a child and birthing is 100% on the women.

> Only in the last couple years has the science begun to be questioned with the possibility that women do in fact make new eggs during adulthood. However, as far as I know that is still an open ended question being studied,

Of all things we know and think we know, we still don't know this? That's a miracle.

I think they were referring to gestation, rather than the initial production of the ovule.

The cost of an egg is negligible compared to the cost of gestation, ie. bringing the embryo all the way to a baby.

Sexuality is a solution to Muller's ratchet [0].

[0] https://thehighbook.netlify.app/muller's-ratchet (first half)

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