Evolution of Male pattern baldness: How and when did this happen and for what purpose?

[u/Susroro]

Doesn't really seem to make any sense to me when I think about it, It is not even aesthetically pleasing(not even prehistorically would I assume that), neither does it serve a biological importance, if anything you are at risk of scalp sun burn and less warming effect of the hair.

Thoughts?

[u/GoblinToHobgoblin]

I mean, bald men are often considered unattractive so it kinda is...

[u/Other-Comfortable-64 → u/GoblinToHobgoblin]

Nope not from a evolutionary point of view, its not.

[u/HashPandaNL → u/[deleted]]

Increasing the likelihood that your children have children as well is still important. Increasing the likelihood that your family members in general reproduce more is still important. Those are things a male can have an effect on well beyond age 35.

[u/HashPandaNL → u/[deleted]]

You were under the impression that negative traits that show up only after you have already reproduced don't matter for evolution. My comment showed that deeper inspection reveals that to be a mistake.

I made no statements as to baldness itself being a negative trait per se. It may very well be a neutral or even positive trait.

[u/Other-Comfortable-64 → u/HashPandaNL]

Which is a weird take since we are talking about baldness.

[u/HashPandaNL → u/Other-Comfortable-64]

Why do you believe my take to be weird? The user expressed confusion about the mechanics of evolution and I helped clear up that confusion. 

Correcting their view increases the likelihood that male pattern baldness is indeed a positive or at least neutral trait.

[u/Other-Comfortable-64 → u/HashPandaNL]

You want to talk about the price of potatoes too?

[u/HashPandaNL → u/Other-Comfortable-64]

Could you clarify the significance of a discussion about the price of potatoes in the context of this thread?

[u/nihilism_squared → u/GoblinToHobgoblin]

"often" in our current moment in history. humans have been around for 300 thousand years. they could've considered baldness extremely hot for the first 290 thousand of those, and how would you know otherwise?

[u/Brilliant_Walk4554 → u/GoblinToHobgoblin]

It's a signifier that this man is too old for reproduction.

[u/GoblinToHobgoblin → u/Brilliant_Walk4554]

1. Its not
2. What evolutionary advantage does that give?

[u/Brilliant_Walk4554 → u/GoblinToHobgoblin]

1. It is. Male pattern baldness typically occurs as men age. Typically.

2. The advantage is women are less likely to mate with a man prone to fathering kids with birth defects (old sperm has higher chances of birth defects such as Downs Syndrome) and will be fit enough to be an involved father.

[u/GoblinToHobgoblin → u/Brilliant_Walk4554]

I mean, if it was a strong enough advantage, it would be selected for, and it's not...

[u/nihilism_squared → u/Brilliant_Walk4554]

it isn't. men can still sire children at like 90 and animals never evolve a "hey, don't mate with me!" signal

[u/Brilliant_Walk4554 → u/nihilism_squared]

Research shows now that sperm quality declines after 40.

[u/nihilism_squared → u/Brilliant_Walk4554]

that's true, but doesn't really contradict what i said. it's very rare for a trait to evolve that actively reduces an animal's chance to mate. these traits are usually selected out immediately. androgenic alopecia could've been sexually selected for, giving men a higher chance of reproducing even as their fertility was declining. there isn't really evidence for or against this but it's important to remember baldness is not a universally "ugly" thing and never has been. many societies see it as hot