[autokad]

males are more susceptible to diseases than women, and probably not just genetic ones: https://www.eurekalert.org/pub_releases/2006-03/jaaj-xck0316...

other explanations included, its no surprise that there's a sudden die off of male lineages in the Y with agriculture coming into the scene.

to me, its another example of yin/yang creation/destruction push/pull where males drive evolution through destruction and females preserve the species dna.

[nyolfen]

you should check out geodakyan's theories:

https://web.archive.org/web/20170213235609/https://en.wikipe...

(wiki was inexplicably deleted recently, i suspect for political reasons via rules lawyering)

> Geodakyan suggested that sex dimorphism gives a species the benefit of having two functional partitions, or subsystems. The male sex is considered an operative, variation subsystem, while the female sex is a conservative one. Sex differentiation allows a species to use the male partition to try out various genetic changes, including parasitic and cooperative co-existence for possible inter-species co-evolution and expansion of ecological niches. In Geodakyan's terms, species use males as an experimental partition of sex and use another partition (female) to maintain the features of the species that were proven to be beneficial.

[astrodust]

This theory, though, seems a bit misguided. Binary sexual dimorphism is probably just the "stupidest thing that works" from an evolutionary perspective, and evolution is nothing if not pragmatic.

Many species don't care for it one bit, though.