Comment by smitty1e
2 days ago
> It’s odd for there to be such an easily-removable design flaw in the human body; evolution tends to remove them.
I wouldn't say so at all. Poor eyesight carries on smartly. Baldness. I enjoy both.
But an old story about the controller code for a surface-to-air missile comes to mind.
Someone looking at the memory allocator spots an obvious resource leak: "This code is going to crash."
The reply was that, while the point was theoretically valid, it was irrelevant, since the system itself would detonate long before resource exhaustion became an issue.
So too prostate cancer back in the day: war, famine and plague were keeping the lifespan well below the threshold of every man's time bomb.
Evolution selects for one thing and one thing only, reproduction.
The answer to every "why hasn't evolution done x" question is selection pressure.
An enlarged prostate is something that people get in their 60s and later. Most people are done with reproduction long before that event. There is simply very little and very low selection pressure.
It's pretty much the reason why most humans have peak health into their 40s.
Don't expect evolution to "fix" anything for humans that doesn't commonly impact 20yos.
Weird that you pull the one quote but ignore the rest of that paragraph which is about how being the leading cause of infertility is exactly the kind of thing evolution normally fixes.
"It’s odd for there to be such an easily-removable design flaw in the human body; evolution tends to remove them. Since it strikes at advanced ages, BPH doesn’t make a big impact on a man’s ability to pass on his genes. But being the leading cause of male infertility sure does. Their explanation is that evolution hasn’t had much time to work on the problem; in animals the spermatic vein is horizontal, and doesn’t have or need one-way valves. It’s our standing upright that yields the problem; in evolutionary terms that’s a recent development."
Not only is it recent in terms of human history; back to my point, it is only in the last few centuries that men in gneral have reached ages that expose the posture shift as a flaw.
There's also your back, your joints, your teeth, GERD. Everything starts getting flimsy in your late forties.
It would probably take too long, but a human breeding program centered around the healthiest still fertile old men we can find and young women with spotless genetic heritage would uplift our whole species.
Older fathers increase the chance of autism, schizophrenia et al.
https://en.m.wikipedia.org/wiki/Paternal_age_effect
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Sounds like the end of Dr. Strangelove.
Ms Atwood would like a word with you.
Mr Trump has also expressed his interest, especially if the women are very young.
Baldness and grey hair are indicators of male maturity. In many primate species elder males look different than younger ones, which guides their social dynamics. Similar reason why our kids stay small for their first 12 years or so - it's hard to teach someone who can physically overpower you.
https://www.jstor.org/stable/2408423
> surface-to-air missile The one link I have at hand: https://devblogs.microsoft.com/oldnewthing/20180228-00/?p=98...
Your appendix and gallbladder would like a word with you ;^)
Both appendix and gallbladder are important. Check the diet for people with gallbladder resection.
I don't have a gallbladder. My diet is that I eat less fried foods and avoid certain dark syrups.
The gallbladder is not important for humans in the aggregate. The aorta, yes.
Also the intakes for trachea and esophagus being close to each other, causing chokes.
Wisdom teeth too.
I once read that wisdom teeth don't fit anymore only because we use forks and knives now. Previously we would tear our food with our teeth, always widening our pallet.
I couldn't find the source just now (in the 30 seconds I searched for it), but I always thought it was an interesting idea.
And tonsils!
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> I wouldn't say so at all. Poor eyesight carries on smartly. Baldness. I enjoy both.
What is the problem with baldness other than having a cheap excuse for not being successful in life? I actually enjoy looking a bit like Larry Fink.
Most people find it less attractive. Usually things that happen when you age are viewed that way, which makes sense, evolutionarily.
For me it was mostly just a major psychological stressor because it happened at a young age. I felt like an old man at 20 years old.
Poor eyesight is evolutionarily recent (not enough sunlight exposure in childhood, rare to find in hunter-gatherer societies). Baldness won't kill you.
I'd be interested to see sources for the claim that poor eyesight is evolutionarily recent.
I strongly suspect it's more a matter of "won't kill you". Nearsightedness is far more common than farsightedness, and it's only in the last two hundred or so years that there's been any major benefit in seeing fine details at distance. The fuzzy shapes afforded by 20/80 vision are plenty enough to hunt a mammoth.
Having 20-20 vision is nice for avoiding lions and tigers, but it's a luxury spec, because movement acuity doesn't decrease linearly with nearsightedness, and movement acuity (plus traveling in groups, as prehistoric humans were wont to do) can take care of business decently-enough on its own - so I wouldn't call it "evolutionary-pressure"-nice.
> not enough sunlight exposure in childhood
Do you have any source for this? As someone born in the summer to a farming family with poor eyesight, I find it hard to believe that happened because I wasn't exposed to enough sun as an infant or child.
I've worn glasses since I was 2.
https://pmc.ncbi.nlm.nih.gov/articles/PMC6678505/
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Don't forget that hunter-gatherers rarely lived much beyond 30. Modern society isn't so bad :)
This is an incorrect generalization from average life expectancies that include incredibly high infant/childhood mortality.
The life expectancy cited by Wikipedia for the paleolithic is around 39 additional years for those surviving to 15.
https://en.wikipedia.org/wiki/Life_expectancy
Samson and Delilah would like to have a word with you. Also with Japanese Samurai. You loose your mythological power, leading to lost status, suicide, ...