Important Question On Male-Female Sexuality

I would say stress on the body

a women's reproductive system is a 27/7 factory constantly in motion. A man's system is more like an on demand delivery service which only goes in motion when needed

Also consider shelf life, A woman only develops eggs once while the man is constantly producing seed. And the host. It's much easier for a 70 year old make to do his part then a 70 year old woman

While it's clear Nature favors the egg over sperm (one egg/millions of sperm), perhaps the reason is due to biology...because sperm production requires a slightly lower temperature than body temp (98.6), the testicles "dangle" outside of the body cavity, suspended in the scrotum. Sperm viability therefore seems assured, despite aging....whereas a woman's egg is "contained", and subject to temperature, and chemical change...just an educated guess.

More responses please. The answer will amaze you because it lays more in the realm of social engineering than biological.

Ok, I give you the answer.

Most would agree that mother is the primary caretaker of a child. So, if women could have children all the way to their death beds, who would take care of those children? It is remarkable that the difference between life expetency and menopause assures that children would be brought up to their adulthood. It's social engineering, not biological.

Yes, also that a woman is born with all the eggs she will ever have, whereas men can continue to produce sperm all their life. Therefore as a woman ages her eggs also age, hence the reason why birth defects are more common among older mothers. You could go deeper with the problems that arise during miosis of both egg and sperm and some argue that many males do seem to have lowered fertility with age due to the proccess. Also men who father children after age 65 have a higher chance of having a child with schitzophrenia.

Of course one could argue that the reason that we evolved this way is because of social engineering, but it lies in a biological expression of that engineering.