I think it's the way nature works. Men can carry on procreating into their 70s or 80s, so nature organises that they have sexual desire right up until the end. Women stop being able to have babies round about the age of 40 (ish) so it's a waste of time and energy having sex! They would be better looking after the children that the have got - and the grandchildren of course! Hence the fall in sexual desire. That's my theory anyway!
Do you think you know when you are going to die?



