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Quirks of Human Anatomy

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Re: Quirks of Human Anatomy

#62
post #15

> f. Nipples are useless in human males (cf. Ch. 5). When I was a kid, I got my tonsils removed "because they were useless and a source of illness". I've recently heard that tonsil removal is now more disputed: it may collect filth, sure, but it may also prevent it from going deeper into the body, which may cause more serious illnesses. Given its vast complexity, and the timeline of its creation/evolution, I remain s…

Let me defend ear twitching. It's a subtle way of communication for those of us so blessed with the ability.

Re: Quirks of Human Anatomy

#63
post #39

Earlier quoted context omitted.

>Given its vast complexity, and the timeline of its creation/evolution I will just say, the human body in particular has only been around for a vanishingly short period of time in evolutionary terms. A lot of the quirks and arguable flaws identified in this piece (painful childbirth through the pelvis, back pain) and others (varicoceles in the left internal spermatic vein, hernias, other pelvic floor disorders) can b…

> human body [...] has only been around for a vanishingly short period of time in evolutionary terms. "as far as we know." Every few years, I see in the headlines stuff like "oldest 'human' ever found in X." The theory of evolution itself has morphed since Darwin [0], and is probably far from being in its definitive form. The timeline remains astronomical w.r.t. a human life, and the perception of a single human. A f…

> as far as we know." Every few years, I see in the headlines stuff like "oldest 'human' ever found in X."

The discovery of older humans does not respond to the point you’re arguing against — in evolutionary time scales, humans are recent.

> The theory of evolution itself has morphed since Darwin [0], and is probably far from being in its definitive form.

Fields continue to change as they grow older, but the magnitude of changes tend to get smaller. Of course evolution will change, but it would be very surprising to have large changes in the fundamental elements

> Thinking about painful pregnancies and birth, [1] hints at the "need" for pain/discomfort.

Evolution only optimizes for what results in dna being passed on. It doesn’t care about ancillary details. I think painful childbirth pretty much shouldn’t matter much to evolution, because the parents have no control over the birth at that point — it’s happening one way or another. Perhaps it promotes bonding with the child, or something like that? But in general, I think it’s wrong to say “evolution provided X, so X must be needed”. If X has no significant effect on the passage of dna, then it could just be random noise.

Re: Quirks of Human Anatomy

#64
post #15

> f. Nipples are useless in human males (cf. Ch. 5). When I was a kid, I got my tonsils removed "because they were useless and a source of illness". I've recently heard that tonsil removal is now more disputed: it may collect filth, sure, but it may also prevent it from going deeper into the body, which may cause more serious illnesses. Given its vast complexity, and the timeline of its creation/evolution, I remain s…

There's also a difference between having no immediate use, and having no reason to exist. From what I understand, sexual differentiation works by having the Y chromosome act as a switch, and both sexes have to share the same blueprint with hormones guided the development of their organs. For males not to have nipples, they'd need to be actively destroyed, which poses a risk for females to also not have nipples, which…

It doesn't seem like eliminating nipples should be any harder than eliminating the uterus...

Re: Quirks of Human Anatomy

#65

Part of this reads like a shortlist of things that doctors and scientists don’t know enough about yet. If you’re looking for a PhD topic, here are some ideas.

I strongly disagree. Literally every item in there makes perfect sense if you have an understanding of how evolution works.

E.g. many of these items are simply vestigial in some sense, where their presence doesn't actively harm the species and it doesn't impose any substantial energy budget. E.g. the current top comment here is about male nipples. Male nipples may be "useless", but they're not actively harmful (and they can certainly be pleasurable during sex), so there is no evolutionary pressure to get rid of them. The perineal raphe (i.e. the "male taint stitch") also has no purpose but is simply a byproduct of how the male forms in utero.

As the article points out, most of the other "quirks" are simply what evolution had to deal with. You may say the eye is "weird" because the photoreceptors lie behind the ganglion cells, but it certainly works quite well, generally. And it doesn't "have to" be this way. Octopus eyes are completely the opposite and a great example of convergent evolution.

Other examples are simply tradeoffs. There is pretty obvious survival advantage for humans having a large brain, but this then adds complexity for how the head gets out of the relatively small pelvic canal.

I honestly didn't see any examples in this list that aren't well understood and well explained by scientists. If anything most of these provide excellent examples of how evolution works.

Re: Quirks of Human Anatomy

#66

Earlier quoted context omitted.

There's also a difference between having no immediate use, and having no reason to exist. From what I understand, sexual differentiation works by having the Y chromosome act as a switch, and both sexes have to share the same blueprint with hormones guided the development of their organs. For males not to have nipples, they'd need to be actively destroyed, which poses a risk for females to also not have nipples, which…

It doesn't seem like eliminating nipples should be any harder than eliminating the uterus...

male and female sexual organs are the same thing inside out of each others, to some extent.

Re: Quirks of Human Anatomy

#67

Earlier quoted context omitted.

There's also a difference between having no immediate use, and having no reason to exist. From what I understand, sexual differentiation works by having the Y chromosome act as a switch, and both sexes have to share the same blueprint with hormones guided the development of their organs. For males not to have nipples, they'd need to be actively destroyed, which poses a risk for females to also not have nipples, which…

It doesn't seem like eliminating nipples should be any harder than eliminating the uterus...

Aren't nipples pretty recent? The egg part has been there for a very long time, nipples haven't evolved as long, maybe in a few hundred million years we no longer have nipples.

Re: Quirks of Human Anatomy

#68
post #15

> f. Nipples are useless in human males (cf. Ch. 5). When I was a kid, I got my tonsils removed "because they were useless and a source of illness". I've recently heard that tonsil removal is now more disputed: it may collect filth, sure, but it may also prevent it from going deeper into the body, which may cause more serious illnesses. Given its vast complexity, and the timeline of its creation/evolution, I remain s…

similar story with the appendix.

Initially considered a useless vestige, now thought to be involved with maintaining gut bacteria.

Re: Quirks of Human Anatomy

#70
post #15

> f. Nipples are useless in human males (cf. Ch. 5). When I was a kid, I got my tonsils removed "because they were useless and a source of illness". I've recently heard that tonsil removal is now more disputed: it may collect filth, sure, but it may also prevent it from going deeper into the body, which may cause more serious illnesses. Given its vast complexity, and the timeline of its creation/evolution, I remain s…

Just like clergymen used to omit "we believe x, y, or z" when making some mystical claims, "scientists" of today omit "as far as we know from their communication with the layman...

>Who would let a junior dev trim bits, or boldly modify a decades old codebase?

Ones who does not understand the idea of the "Chesterson's Fence"

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