I’m new here, so go easy if I’m out of line on these.
I was just wondering why your own, uh, emanations tend to smell good to you, but bad to everyone else? This sounds crazy, but many of my colleagues report similar self-satisfaction but find second-hand wind repulsive. What’s the deal?
[WAG]
Acne is caused largely by the unavoidable hormonal imbalances of puberty. Puberty is a time of rapid growth and maturation and is almost unique to humans. Most animals grow at a fairly steady rate throughout their lives, with physical and sexual maturity creeping up on them. Humans have a ridiculously extended childhood, far longer than is required for physical development, which is assumed to be necessary to allow our brains to develop. If humans matured at the same rate as something like a cow we’d have two year old children walking around in the bodies of grown men and wome. Although capable of reproducing physically the could never take care of their offspring and teach them all they need to know and would also be a danger to themselves and others when the inevitable fights began between 180 pound 4 year olds throwing temper tantrums.
So instead humans develop mentally while physically too immature to be a threat to themselves or others. Then when we have the necessary knowledge and skills we go through a massive growth spurt to make up for all that lost time. The only other alterantive would be to spend another 12 years growing at a steady state from a 35 kg twelve year old boy into an 80kg man. We’d be 25-30 before we were sexually mature.
The downsid of that masive growth spurt is that your body, and the bacteria on your skin, aren’t given time to learn how to balance body secretions, by endocrine and exocrine so we have acne. It’s unsightly but temporary and most people get over the worst of it in 5 years. Less time wasted than would be if we were still growing at a constant rate.
Acne is also at least partially environmental. It’s very susceptible to sunlight for a number of reasons and is also propably aggravated by the high nutritional standards most people in the developed world have. In ‘traditional’ human societies acne was probably less of a problem.[/WAG]
The fart thing is probably purely psychological. I imagine that if we bottled your farts and then realeased them back at you at a later date you wouldn’t be able to distibguish them. Not that either of us is going to volounteer to perform tht experiment.
All true, but natural selection is not 100% efficient. With so many forces affecting the evolution of the species, you can’t expect EVERY undesireable trait to be weeded out. I’d guess that, in the long haul, acne hasn’t had much of an effect on reproductive success, so it hasn’t been that strongly selected against. Apparently, other traits, such as brain size, have turned out to be far more significant - so you can look back over the history of the species and see an significant increase in brain size over time.
This is completely anecdotal, but bear with me. When I was a kid, I remember virtually all ance advice saying “you’ll grow out of it”. And, as I recall, almost no adults at that time had acne. Now I’m 28, still have moderate-to-bad acne, and so do a large number of my same-age friends. Nearly everyone I know my age or younger has some level of acne, but most people I know who are 40+ have none. So I have to wonder if there is something envitonmental, such as increased hormones in the food/water supply, that has changed. It is entirely plausible that exposure to low levels of hormones and/or hormone-like compounds during a formative period (our collective youths) has caused sufficient imbalance to exhibit as acne. People who were too old to be sensitive when these hypothetical hormones started to enter the food chain would still be acne-free.
This is purely a wild-ass theory, but has some basis in reality - several sources have told me that there has been an increased incidence of male breast formation in the past decade, presumably due to estrogens in the diet.
My point was that the current life-long acne that many of us experience may be environmental, not genetic.