Genome

I am busy reading "Genome - The Autobiography of a Species in 23 Chapters" by Matt Ridley.

This is an excellent book - kind of makes me wish I had studied evolutionary biology.

Interesting observation. I had understood that natural selection favours mutations that were in the "best" interests of the entire species. Well not so, because X-Chromosome mutations are sometimes only in the interests of women and are to the detriment of men (not enough to wipe them out entirely - at least not yet). The Y-chromosomes are pathetically small, encode for many genetic disorders and because there are 3 times more X chromosomes than Y chromosomes in circulation there is more opportunity for them the undergo change.

I quote

In the past the ability to seduce a women was good for Y-chromosomes but the ability resist seduction was good for X-chromosomes

Thus we've had a genetic conflict of mutations and counter mutations.

Also men have only one Y thus there is no redundancy like women have with their two X chromosomes.

sigh ...