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Frequent-Seaweed4 t1_ivb15th wrote

Humans are special in reproduction amoungst primates because of our upright gait. Human babies are born much earlier in development than most mammals, which is why they're comparatively helpless for the first few years.

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miasabine t1_ivbcsof wrote

Human infants have disproportionately large heads compared to most other mammals as well.

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AlternativeBasket t1_ivbfgu9 wrote

human evolution was an arms race between bigger heads (smarter) and women's pelvises (being able to still walk )

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grumble11 t1_ivc49z6 wrote

Not just that, but calories - the brain takes up a huge chunk of calories during infancy, massively slowing development, requiring more calories and making kids more vulnerable to famine

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ledditlememefaceleme t1_ivd7iv3 wrote

And yet people insist we're magical and special because we're designed.

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Drmite t1_ivdgcsz wrote

When I was a kid still grappling with the whole religion thing, I just took it as the vibe being a set of parables to learn from. If a god exists, it's through the invisible visible sciences of physics, evolution and all that fun stuff.

Now it's good ol science.

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HolyNewGun t1_ive5zd1 wrote

Yes, precisely that a species with so much paradoxical feature like human should not exist. If human acquire bipedal first, then it should heavily select against big brain according to natural selection theory. But since natural selection pretty much attribute everything to randomness, the theory practically unfalsifiable.

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BoxingSoup t1_ive5vzj wrote

You just went through a whole thread on why we are special in design, and your takeaway was that we are not special?

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aldhibain t1_ivedten wrote

We are special in design, but we were not designed to be special.

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ledditlememefaceleme t1_ivgces6 wrote

We're neither designed, nor special. We may have some (A dwindling list) features unique to us, but that's it.

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crazyhadron t1_ive494i wrote

Nah, the bottleneck (heh) is the amount of energy a baby needs to survive within the womb. Birth happens when the placenta's throughput isn't enough to sustain the baby much longer, and it triggers the delivery process.

Kinda wonky to think that boobs are able to push much more nutrients through them than the placenta itself. Anywhere between 500-700kcals, that's as much as the brain itself uses and it's the most energy-intensive organ in the human body.

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Koshunae t1_ivdq1d2 wrote

If we developed medical science earlier and perfected cesarians then we could bake longer and be more developed prior to birth

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ClancyHabbard t1_ive0s68 wrote

Placentas don't really do well after about 42 weeks (a normal human pregnancy is about 40 weeks), so that would also be an issue that would need to be solved.

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sleepyr0b0t t1_ivedxtm wrote

Nope. It would be very hard to walk and live in general. Just create artificial womb then.

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Frequent-Seaweed4 t1_ivbpsmt wrote

Part of the problem. A big brain can take up a lot of space for a live birthing organism. Imagine the head of a baby at 3 months being pushed through the coochie

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miasabine t1_ivbt4dv wrote

I spend a great deal of my time trying not to imagine a newborn being pushed through my fun bits, so I’m going to pass on the mental image of a 3-month old.

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fredsam25 t1_ivep5kl wrote

Our premature, tiny babies literally tore my wife in two, on two separate occasions. I feel very sorry for women who have full sized babies.

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miasabine t1_ivf1hgl wrote

Oof, your poor wife. Hope she recovered with no lasting damage.

I have nothing but respect for people who give birth, that shit is brutal, I could never do it. I have a bit of a pregnancy/birth phobia and it’s just amazing to me that people voluntarily put themselves through it. More power to them.

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herbw t1_ivcgi13 wrote

Crowning as a part of delivery, indicating imminent birth, would gross yer out.

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miasabine t1_ivf0utb wrote

I’ve seen footage of vaginal births. It’s not so much that it grosses me out, more that it sends me into fully fledged panic attacks. All due respect given to those who go through it, I could never.

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herbw t1_ivfwelq wrote

with all due respect, birthing is a reality of billions of years, and billions of events/year. . if you can't handle reality, then there's a problem.

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miasabine t1_ivgcrpb wrote

Birthing humans have only been around for a couple hundred thousand years, and something being reality doesn’t preclude it from being a phobia. If that were the case, there would be no phobias. Pregnancy and birth still kills thousands upon thousands of women every single year, and leaves many others with chronic pain, PTSD, and various disabilities. Lastly, and with all the respect you are due, which incidentally is precisely none…

I have no problem handling reality. I knows births happen, I have no difficulty accepting that. I celebrate births when done by people I know, and I find great joy in watching the resulting humans develop and grow into intelligent, capable adults. I personally merely find the prospect of birthing intensely and viscerally unappealing. So I take steps to ensure, to the best of my ability, that it’s a situation I never find myself in, while maintaining the utmost respect and admiration for those who do.

If you think that’s a “problem” in any sense of the word, you’re more than welcome to your opinion. However absurd and pathetic it might be.

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herbw t1_ivjpx3c wrote

Wrong there, too, as we as a species have been around for ca. 100K yrs, by the bone evidences. Altho our ancestors have been around for billions of years. Just look at the mitochondria.

Well, we learn to accept the reality of the facts we ALL got here by copulation, or fkn in the parlance, and we get here by being born. Refusal to face truths is ever a serious problem for our species. Because denial --->>> delusions. & ignoring reality. Frankly workin in OB was one of the best times I had in Medicine. Happiest place in the Hospital. New life, new babies. The future or our species just there.

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miasabine t1_ivlk7d1 wrote

Every source I’ve read says between 2-300,000 years.

Yes, we all got here through sex and birth. Not once have I disputed that.

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herbw t1_ivqid52 wrote

Homo genus, but NOT us, modern man, H. sapiens sapiens. We are not that old. Cro-magnon is older but a close chain, likely big pieces of those in our genomes, too.

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herbw t1_ivos3r5 wrote

Fine, then yer cherry picking the data. Violation of the comprensiveness rule. Modern humans are about 100K yrs old, or so. The data in east AFrica bone finds show that, very likely. Our ancestors go back 3 billions years. H. erectus was about that old over 100K to 300K yrs. . but not entirely human.

Our cortical cell columns are better than erectus. Closer to cro-magnon. Nor has human evolution stopped. Our continuing techno capabilities shows that. Follow tools making from the stone age, to present tech. Humans are getting smarter. That's been going on for 100K's of years in us and our ancestors. Our cortical cell columns, where the info processin goes on, are more efficient and more of them than our ancestors, even 10K yrs. ago.

How do our brains create information? Why has THAT question not been widely asked? Answering that deep question shows how, the brain processors create creativities. Where creativity likely comes from in brain. Structure/function general model in biology, and most tech, t00 Here's now it's done.

https://jochesh00..com/2017/05/01/how-physicians-create-new-information/

Please fill in the details on mankind's likely descendancy to a more complete form.

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miasabine t1_ivpc3dp wrote

“Approximately 300,000 years ago, the first Homo Sapiens - anatomically modern humans- arose alongside our other Hominid relatives.

https://www.forbes.com/sites/startswithabang/2019/05/15/what-was-it-like-when-the-first-humans-arose-on-earth/?sh=680fb5b56997

“While our ancestors have been around for about 6 million years, the modern form of humans only evolved about 200,000 years ago.”

https://www.universetoday.com/38125/how-long-have-humans-been-on-earth/

“Modern humans originated in Africa within the past 200,000 years”

https://www.yourgenome.org/stories/evolution-of-modern-humans/

So no, I’m not cherry picking data.

The rest of your comment is irrelevant word salad. It has nothing to do with what we were talking about, you’re just talking for the sake of it, and I have no interest in engaging with it.

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herbw t1_ivqgh66 wrote

forbes is not an anthropological mag. OK?

Modern humans arose about 100-125K yrs ago in east africa. before that it was H. erectus which is NOT modern man. OK, they are considered in the Homo Genus with modern humans. That's the big error they are committin there.

Homo neanderthalensis would be modern human by their criteria those been extinct for 10K's of years.

It's basic biology. H. sapiens sapiens. Forbes does NOT make the clear use biological definition clear, either

Humans with our high social forms and intellectual characsteristics are about 10-20K yrs old. but as we cannot tell intellectual linguistic prowess but by stone age tools and bones, we estimate the first humans most like us, physically, came about 100-125K yrs ago. Cro-magnan is older than we too, but a side chain as well.

It's anthropology, NOT Forbes business news specialty, either.

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miasabine t1_ivqjc4z wrote

Lmao, I love how you’re focusing on Forbes when I’ve literally provided you with THREE other sources that all say 2-300,000 years. And yet you’ve provided ZERO sources. Just get the fuck out, you’re fucking pathetic

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specialkk77 t1_ivbyawr wrote

Ehh their heads don’t get that much bigger in 3 months. Scarier to picture pushing out a toddler instead, double the head circumference, double the weight, 10-12 inches longer…

Well, I just gave myself nightmares!

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PaulAspie t1_ivdot6y wrote

By three months, their shoulders are bigger which can be as bad.

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Libriomancer t1_ivckpz3 wrote

I was a 10lb kid with a massive head. My mom normally weighs 90lbs but crested over 100lb when she was pregnant with me. I feel like she doesn’t have to imagine as I’ve see pictures from right after I was born and I’d have made Dudley Dursley look like a tiny baby.

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ventricles t1_ivcr0ei wrote

I was 2 weeks late and so big when I was born that I broke my collar bone on the way out

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herbw t1_ivcgdij wrote

Babies before delivery also have un-closed cranium bone sutures, so those can overlap, and become smaller diameters for delivery.

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allcommiesarebitches t1_ivd1lg9 wrote

So that's what those soft spots that are fun to push in on babies' heads are!

Like human bubble wrap

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herbw t1_ivds1v8 wrote

No, those are open spaces between the bones, called fontanelles. and they close over as the babe grows.

That is a serious defect in babies' anatomies. they can be very easily killed or seriously injured because the brain is not there covered and protected by bone.

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allcommiesarebitches t1_ivdw8yk wrote

I thought it was just soothing them to sleep. So that's why those guys chased me out of the maternity ward! I thought they were jealous of my fathering.

^in ^all ^seriousness ^that ^is ^interesting ^ty ^for ^the ^info

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kubat313 t1_iveexfg wrote

So theoritcally you coule put something in there and when it grows over it would be in your brain like a chip.

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herbw t1_ivfwzgx wrote

sorry, the events of biology and medicine doesn't work that way. There may be scarring , and if on cortex cause seizures, and create permanent disabilities, but it's not necessarily lethal at once.

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EmulatingHeaven t1_ivda5qj wrote

It’s also why they come out all cone headed after vaginal delivery

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[deleted] t1_ivet6a4 wrote

[deleted]

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herbw t1_ivfwk4c wrote

Yes, seen those. I Like OB, & it's usually the happiest place in a hospital.

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MuddyBoots287 t1_ivdbfqb wrote

Hi, yes. Just had a baby 7 weeks ago. His head was 16” at birth (average head size of a 3 month old). Can attest it was not the most fun I have ever head!

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Apokolypze t1_ivdw13j wrote

I am so sorry for your woman parts. And also for the probable sleep deprivation youve experienced since. Moms really are superheroes.

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herbw t1_ivcg7gg wrote

Maybe because we have bigger brains, far, far more cortical cell columns in cortex and quantitatively and qualitative advantages, too.

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Admetus t1_ivdgri4 wrote

It's amazing really. When you compare the size of a baby's head to an adult it's incredible how much their brain develops. It makes a lot of sense that the newborn is sort of an instinctual primate from the beginning and then through nutrition and nurture becomes a human being.

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herbw t1_ivdro0p wrote

Considering that brain can use about 20% of both circulation and foods, it's not at all unusual.

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Admetus t1_ivdzixu wrote

All thanks to agriculture (or if further back, the hunter-gatherer beginnings of man)

I heard also that two legged and furless results in less consumption of nutrition.

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Applejuiceinthehall t1_ivbi7ca wrote

Actually, humans have the second longest gestation than other great apes adjusted for size.

The skull size ratio for baby humans is 30% of adult size. For chimps, it's 40% of adult size. So, for humans, that would be about the size at 3 months. There are already women who have hip width that can accommodate that.

Additionally, when studying the gait, wider hips do not make women worse walkers/runners.

So it's probably not that babies came out to accommodate women, but that started being born early for another reason and women's hips width is that size because of baby

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Frequent-Seaweed4 t1_ivbpm2i wrote

We suspect babies started being born earlier because while some women can accomodate a child with chimp-birth requirement, many can't, and this is a population genetics question, not a mendelian genetics question.

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OddEpisode t1_ivbyj2s wrote

I don’t get it

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mrs_shrew t1_ivc9q6j wrote

Women who gave birth to chimp babies more often didn't like it so they stopped/died in childbirth. The ones that were ok with chimps were also ok with normal babies so the survived

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DildoDouchBaggins t1_ivchw5c wrote

I heard the female body has ways to tell if it's a legitimate chimp...

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mrs_shrew t1_ivdv44g wrote

If it's a chimp they can sort of shut it down so it can't continue.

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grumble11 t1_ivc7ctn wrote

Yeah, but if there was a huge advantage like skipping three months of potato-like infancy, women would shift rapidly genetically. That isn’t a barrier if it already exists in the population

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Applejuiceinthehall t1_ivc8ydl wrote

That was the idea, but it doesn't pan out when you look at the evidence. Some women can already accommodate that size skull. So if babies were born with a 3 month olds skull, then the selective pressure would be for wider hips.

Because of women with wider hips, we know that their walking/running isn't impeded with wider hips.

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Frequent-Seaweed4 t1_ivcb6wr wrote

Okay but you keep saying "some" women, when we're talking about the "average" woman.

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Applejuiceinthehall t1_ivceqf5 wrote

But it's only the average because human babies don't have skulls that are 40% of adult skull (which chimps have). If humans were born with that big of skull then women with wider hips would have been selected for and women with narrow hips would have been filtered out

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herbw t1_ivcftpy wrote

Human reproduction is complex system. The pelves of PG woman will expand due to a substance which causes the cartilage of the pelvic bones to relax, so the birth canal widens. to allow easier deliveries. When a pelvis of a woman who has given birth to a child/children is found we can see that on post mortem. How we know it.

Gestating babies, and delivering them is very complex system & has many, many interesting events going on, too.

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Miss-Margaret-3000 t1_ivdfh5y wrote

I saw something interesting from Be Smart recently saying it’s likely a combination of the size parameters and where a human’s metabolic rate maxes out. A woman’s running at approximately just over 2x her normal metabolic rate from crafting a baby once their at 40 weeks which is the majority of peoples maximum sustainable rate. It’s still emerging research, but I thought it made a lot of sense.

edit: Remembered it was a different show

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anotherbozo t1_ivcpdcg wrote

That's interesting; never thought of that.

Now that I do, so many animals give birth to babies that instantly try to stand.

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D-redditAvenger t1_ivcl7pn wrote

I wonder how much that accounts for our more developed social interaction, because we are forced to be dependent on each other longer.

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coopermoe t1_ivcxnmc wrote

I wonder how long our gestation period would be if our kids did come out fully cooked? 18 months? That would be tortuous

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Apokolypze t1_ivdwepw wrote

I'm not sure the human metabolism could take much more stress than what the 10 month pregnancy already puts on mothers....

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kubat313 t1_ivef37v wrote

Probably more like 24 months. Is my fully uneducated guess.

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PhantomRoyce t1_ivcpit0 wrote

I wonder how long a human would have to “develop” in the womb before they’d be on the same level as other mammals.

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hipchazbot t1_ivd3d96 wrote

God they're useless. Stop being such a baby 👶

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5a_ t1_ivf1d5o wrote

yup,elephants can walk from almost the moment they're born

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Dalisca t1_ivh7q01 wrote

I'm curious how long our gestation would be if we gave birth at comparable levels of development.

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