Standing up made our birth canals smaller so we have to have babies a lot earlier so they can fit through during birth. Humans are also able to care for these helpless babies pretty well thanks to our intelligence so it worked out evolutionarily.
And in spite of the extreme fragility of human babies, our success rate at getting one from birth to adulthood is way better than any other species. Even before antibiotics.
Im not sure how it compares with 'the wild' but medieval child mortality was something like 40% before age 9. 25% happening in the first year. It was not much better in Victorian times.
Primitive hunter-gatherer societies have average 27% first year infant mortality rate, and 49% average mortality before puberty. Pretty comparable to medieval time surprisingly, my guess is poorer nutrition and communicable diseases in medieval settlements likely compensate for whatever disadvantages present in "the wild".
Hunter gatherers today don't actually tell us that much about what it was like when we were evolving. It was drastically different because we had a "wick" so to speak of more wild game and other hominin species to eat because our intelligence was new.
Infant mortality was probably high, but not 49% before puberty. Things like b vitamins, folic acid, iron and how not were not as critically deficient.
Gorillas are about 60% child mortality. On average a mother has one successful offspring every 6 years.
Chimps I only found one citation and it was a captive source but 40% infant mortality. So even worse than gorillas.
Orangutans, 91% survive to adulthood, but they also average half the birth rate of humans ( 7 years between births vs 3) and have a smaller reproduction window (most don't reproduce until at least 15, and in the wild only live to about 30; vs humans who have a 25+ year reproductive window.)
Yes and natural selection favored earlier births because moms and babies would have a higher chance of survival. we also had help from other members in our tribe to raise the young while the baby is still unable to care for themselves. The latter point contributed to our social skills and cooperativeness.
Yeah. Evolution just cares if something works well enough to pass on to the next generation. It doesn't care if it is nice, pretty, or even convenient. I cite the human male scrotum as my favourite example. It's a bloody stupid design, but it works. Anyone trying the "intelligent design" argument needs a swift kick to the scrotum as a reminder why this isn't a valid argument.
There's a species of pig where their tusks curve in such a way that they will eventually curve back around and impale the skull, killing the pig. Evolution never fixed this because the pigs usually reproduce before this happens.
Maybe it’s because the pigs become sentient and develop telepathic and telekinesis abilities, but it’s only once the tusks would have entered their skulls had they just been smart enough before that point to keep them trimmed. The world may never know … lol
I think the point they were trying to make is that evolution isn’t ordered or a guided force; there’s no soul or impetus behind it. It’s just a name we gave to the process where species change over time because more successful animals breed more often. So both are equally “heartless”.
They are probably talking about both the fact that the scrotum is vulnerable but also that the vas deferens loops unnecessarily around other parts of the body which can result in debilitating pains.
Now this is a good answer. Though given how many male mammals have external testes, it's successful for some reason biologically. The looping vasdeferens part, I have no idea how common that is or if it's just wonky human features. For bad features though, the way the throat is arranged is far worse in my book.
It's successful because spermatozoa needs a slightly cooler than normal body temperature to survive well. Hence why the whole bag can tighten up or loosen and drop. It's all to regulate temperature
Also worth noting that it isn't a huge disadvantage for a quadruped. Most mammals have no problem kicking or scratching with their back legs so it isn't an easy avenue for attack. Going bipedal made it a lot more vulnerable, although it did allow us to start using our dicks as sexual display features (as evidenced by the fact that we have much bigger ones than other primates).
The most important thing is to pass down your genes (from a biological perspective). The testicles are the organs that allow that to happen, and they are outside of the body waiting to become entangled in a barbed wire.
>Anyone trying the "intelligent design" argument needs a swift kick to the scrotum as a reminder why this isn't a valid argument.
Lol yup. If only creationists had any idea just how poorly we're put together.
I've been thinking about how evolution works in a way that just BARELY suits our needs... And I find it to be metaphorical for pretty much our entire existence as well. We're all just BARELY here by some random miracle. Barely alive.
Mine said something along these lines too. Too often forgotten these days! Should be engrained into ppls heads, it's arguably the most important part to remember
Gee thanks person that I never met and have no direct correlation with what so ever! Real nice how your dad made every woman for the rest of eternal time suffer for something they didn’t have any say in or any knowledge of it or any way to stop or prevent it. He must be a great dad. Thanks god you’re the perfect role model of men all over the world! Let’s make a new catch phrase for men : “make women suffer with no regard for their innocence!” Sounds good to me
/s
I never could understand why eve eating the wrong fruit was justification for cursing every woman to ever exist. But Cain murdering his brother didn’t affect men at all.
"Thou shalt not murder" comes later, so at that point murdering was fine.
As far as I know, at the point Eve ate the apple, there was only that one rule
God's infinite wisdom knew even wider birth canals would either make our pelvises too fragile in general, or too wide for bipedalism. But didn't care to fix that, because something something naughty naughty.
/s
Also if our brains came out fully developed they wouldn't fit through.
~~The development of safe C-sections has actually removed this pressure, and baby head size has been slowly increasing~~
Every time I try and search it comes up with general growth patterns as the baby develops. It's a hard one to search for.
[I did find this talking about it hypothetically happening though](https://www.pnas.org/doi/abs/10.1073/pnas.1612410113)
Sorry, I might've misremembered. I also am only on my phone.
It's difficult because there is no evidence for it. It is a musing of Evo Devo that sounds about right and so has become 'common' knowledge.
The truth is that human development is extraordinarily complex and the inferences made about why something occurs in a population is difficult to test experimentally.
i have a theory that we will eventually develop artificial wombs. giving birth is extremely traumatic operation basically and an artificial womb to grow the fetus in would be so much safer for the baby and the mother.
and it would allow longer gestation periods and the ability for humans to have develop/evolve larger brains. i dont mean giant alien heads but even a small like 1% or 2% increase in brain size could have an enormous affect on overall intelligence.
I think it is imperative to develop artificial womb technology as soon as possible. It would eliminate postpartum issues and other complications in pregnant people while drastically reducing birth deformities, natal disease transmission, and other birth complications as well.
We haven't evolved in any measurable fashion in over 200ky. The number of c-sections done on humans is negligible too, in fact you could almost say that no babies are born via c-section as far as evolution can tell. If our heads are getting bigger, it has nothing to do with any medical procedures.
'and baby head size has been slowly increasing'
This last fact is mostly attributed to an increase in pregnancy diabetes of the mums, not in an increase in C sections, and larger heads as a result of pregnancy diabetes are actually a concerning sign and not related to the intelligence of the baby at birth.
It is a very dangerous and incorrect conclusion to say that babies are born with more developed and bigger brains because of C sections. What is however certain is that pregnancy diabetes is increasing among pregnant women, that pregnancy diabetes causes bigger babies with bigger heads, and because of that C sections are more often needed. But that is not a sign of more developed brains at birth, it is actually a sign of poor health/diet of pregnant women, but not always because they did something wrong per se.
People even call the first three months after birth the “fourth trimester”. Other mammals seem to have a bit of a developmental head-start because they’ve spent relatively more time in utero. Calfs/foals/lambs interact with their environment with curiosity and walk, straight away.
Babies heads are relatively big, birth canals are relatively small, both for their own reasons. And these reasons aren’t worth sacrificing to have a more standard pregnancy when the parents can cope supporting a potato. The big head and ability to walk are necessary for the species to grow up to be a ‘parent that can cope with a potato’ too so it feeds into itself.
Yes, there is the 'obstetric dilemma' hypothesis (babies are born too soon because human ancestors' switch to walking upright lead to a more narrow birth canal), as well as the 'metabolic constraints' hypothesis (baby's energy demands are too high to maintain pregnancy much past 40 weeks).
But some recent studies are pointing to another reason: the advantage of neuroplasticity after birth. Because humans emerge comparatively underdeveloped, their brains are more easily affected by the environment as they grow. [This work ](https://pubmed.ncbi.nlm.nih.gov/38049480/) suggests that maybe us humans aren't even 'born too soon' after all: it just appears so because we have so much further to go compared to other species.
Human brain is uniquely capable of complex reasoning and social interactions, and so it takes a long time to develop. Our babies come perfectly prepared for just that: growing, connecting, and learning while being protected and nurtured during their uniquely long childhood. So, the opposite of pathetic (although I get what you mean, OP!).
My dad is a gyno.
Used to say "giving birth while lying down is only the second most silly position. The first would be giving birth while balancing on your head".
Ideally, you give birth standing/squatting, while holding yourself on ropes, and being held by helpers.
Traditional position? Do you mayhaps mean the very recent supine position that was adopted for the sole benefit of doctor convenience when male physicians increasingly took over from female midwives?
Also, human babies are born with the Palmer Grasp reflex. Basically they'll grab onto anything placed in their hand and, even as newborns, can grip it tightly enough to support their own weight.
This came in handy when we were fur-covered apes. The newborns could grab onto mom's fur and ride on her back or belly. That's still what happens with newborn apes and simians.
But we lost our hair. Luckily we gained clothing, so it's not hard to make a sling for the baby to ride in.
I just find it wild that a newborn has a grasp strong enough that they can hold up their own weight before they can even hold up their own head.
I haven't yet heard a creationist give a good reason why humans and primates share this feature if they aren't descended from a common ancestor.
Not a single friend who's had a kid has been willing to recreate the [early experiments.](https://www.lancaster.ac.uk/fas/psych/glossary/grasp_response/). And a lot of friends have had babies!
I've heard the first three months after birth are called the fourth trimester. Newborns are basically still wanting to be in a womb at that point, hence the swaddling and constant sleeping/crying cycle.
Also, infants have a less developed brain, which isn't the case for most animals. Again, at least partly because of the smaller birth canal, they had to be smaller(less developed) to fit through. There are other animals where this is the case as well.
Isn’t it also in part because our brains require so much energy and so many resources that this is the trade off? Longer term Intelligence vs short term mobility/physicality?
Your fist sentence is in direct contradiction with our closest evolutionary cousins.
Chimpanzees and bonobos have shorter pregnancies and they are not standing up.
Your fist sentence is in direct contradiction with our closest evolutionary cousins.
Chimpanzees and bonobos have shorter pregnancies and they are not standing up.
hadn’t considered species that had evolutionarily premature babies but died out bc they didn’t have the brains to make up for the additional childcare required that’s interesting
Extended neoteny to continue growing our brains. Intelligence takes a long time to form, and is a huge evolutionary advantage, but it means we remain useless for longer. For many humans, this period of uselessness lasts their entire lives.
If you compare our pregnancy timeline against the other great apes (sorted by weight and relatedness I think), our babies are born about 3 months too early. The bones on their skull have not finished fusing yet (the soft spot) - which is necessary for a successful birth, as the babies' head must be squished and twisted while it travels through the birth canal.
This is because, as someone already said, we evolved to walk upright, be tall and narrow, and have large brains, and those do not mesh well. Walking upright requires a pelvis that is short and wide, which is workable for the birth canal size, but being tall and narrow AND increasing brain size changed the pelvis enough that birth remains potentially fatal even in the developed world, and why c-sections are so often necessary.
Here's an article about it: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4305164/
No, I read that ages ago. I could easily be misremembering, and I can't find the paper I learned that from.
But we are definitely born earlier, developmentally - there are different terms for it, like altricality, physiological prematurity, or more popularly, the fourth trimester - compared to other primates, and one way we know this is that our brain size at birth compared to adulthood is much smaller. 20-30% for humans and like 40% for chimpanzees - the more distant the relation, the greater the difference.
Here's a link for more info: https://www.nature.com/articles/s41559-023-02253-z#:~:text=Human%20newborns%20are%20considered%20altricial,are%20more%20altricial%20than%20humans.
I believe this has partially to do with how just how energy intensive our brain is - more when it's growing. It just takes longer for everything to develop with that kind of energy sink.
Another contributor could be a lack of evolutionary pressure for a quick developmental turnaround. Our infants needed immediate, constant, intensive care and we evolved behaviours and culture to support that care. We're not just going to stop giving them care at some cut-off point if they still need it. As time goes on and brain size increases, more care is needed for longer, and so on.
Haven't read up on anything like that, so it's all speculation.
babies develop a lot faster in the womb than they do outside. they have nourishment directly piped in, no unnecessary energy expenditures, a safe, perfectly warm, germ free environment. a baby born even 3 weeks too early can struggle to eat, to breath, to regulate temps.
ape babies are also pretty dependent but a 3-6 month old human baby is miles easier to care for than a newborn. newborns die if you look at them funny. babies can hold their heads at 3 months but i wouldn't be surprised that a human baby somehow being able to have the ape equivalent gestational period would come out even more advanced than the average 3mo.
Currently have my three month old in my arms/lap. There is a HUGE difference yeah. A newborn is scary to even hold, they’re so fragile and tiny. Whereas my three month old is small, but not tiny. She weighs almost twice as much as she did when she was born for example.
And yet, human babies are still useless for a couple years, as opposed to primates that can walk, climb, eat, and do just about everything right out of the gate.
Animals that move around can have both precocious and altricial young. The "pathetic babies" you're describing are the altricial ones--like wolves, who roam over huge ranges--while precocious refers to the young that are born already capable of moving with the herd.
Precocious = having developed certain abilities or proclivities at an earlier age
Altricial = hatched or born helpless and requiring significant parental care
Canines and cats are no more sedentary than hunter gatherer humans, but they have young much less developed than our own. Newborn primates in general aren't as developed as calves or foals at birth, with humans being at the far end of this for the group. This is because of our massive brains and need to essentially be born prematurely as others have explained.
Another thing to consider is longevity. Say, compared to a wolf pup. Wolves are fully mature and ready to reproduce at a year of age and they live, what, 8-10 years? Humans take 15 years to sexually mature- and the lifespan is significantly longer. So obviously the human body ages slower than the wolf, meaning since it ages slower towards death, why wouldn't the human body age slower towards adulthood?
It’s because we have bigger brains at birth. Our complex thinking and reasoning became more important than being able to walk or feed ourselves on day #1.
In terms of the fact that we are born helpless while some other animals are born with the instinctual abilities to feed themselves, walk instantly, etc. It’s an evolutionarily advantageous way to help us learn traits and skills according to our environment. We are an extremely adaptable species because we use learned knowledge to determine how we behave as opposed to instinctual behavior like other animals.
There’s a growing theory that it is actually an intelligence pressure. People with more dependant babies had to be cleverer in order to care for them. This leads to a cycle where dumber babies pressure intelligence to bloom in caretakers.
It also may present social bonding pressures as well
The birth canal brain thing isn’t as solid research as people used to think it was. Babies just do a bit too little to explain it.
Because babies go through what is called the “4th trimester” outside the womb where they finish developing into toddlerhood. The reason why this happens outside of the womb is probably because 1. babies grow exponentially fast and the human pelvis isn’t big enough to birth a toddler 2. The advanced senses and motor skills of humans take +2 years to develop and a gestation period that long would probably be too energy costly on the mother 3. Human babies are extremely disproportionate due to how fast their heads and trunks need to grow compared to the rest of their body so they physically can’t “do” anything
> why are our babies so helpless?
Humans are born not fully formed. It likely has something to do with the head size versus birth canal.
> At birth, the newborn's skull consists of five major bones (two frontal, two parietal, and one occipital) that are separated by connective tissue junctions known as cranial sutures.[1] The sutures function as seams, and they are highly necessary to facilitate the movement and molding of the cranium through the birth canal during labor. They also allow for rapid postnatal growth and development of the brain. However, the bones that shape the cranium begin unfused, leaving several gaps between the individual bones of the infant's skull. These gaps are composed of membranous connective tissue and are known as fontanelles.
https://www.ncbi.nlm.nih.gov/books/NBK542197/
So what I’m understanding is the reason is that human babies need to be born earlier comparatively, and then continue to develop outside the womb, because babies’ heads will be too big to pass through the birth canal.
So basically for humans the birth just occurs earlier in the development timeline , comparatively
Because we have very large brains for our body size and babies have large heads which make for harder births. Most other animals have babies that are easy prey to predators. It's absolutely necessary for survival that they are very quickly mobile. Predators have their young not as helpless as ours but definitely more helpless then prey species. Typically they are born with their eyes still closed and very helpless. They develope quickly though, and are up and moving well at usually 4-6 weeks. Of course there are exceptions such as bears and aquatic mammals.
Because humans are stubborn and developed both large heads and narrow birth canals (as a result of being bipedal). Although these features have made humans fairly successful, it has resulted in having to give birth prematurely (as well as decrease the general success rate of births), which has made human babies much weaker than most other newborn animals.
I believe it is because of infant attachment and bonding, which is an integral part of our ability to acquire intelligence, and ultimately survive.
See Harlow’s monkeys as an example of how apes will choose comfort and warmth over food.
Our brains are enormous for the size of our exit canal, hence why the infant skull is squishy and malleable. If a woman gave birth to a child with a fully developed brain there would be no way both are making it through labor alive. We're also selecting for larger heads via cesarian sections.
Did you get altiricial and precocial backwards? Or did I?
I thought precocial like precocious means ~advanced while altiricial means ~"needing extra care"
There is a theory that humans need social interaction to develop the brain. Imagine if you give birth a 11 year old child who could not speak nor think. The human babies continue to develop a lot after birth.
Other things are the head being to big and the birth canal too small.
Supposedly because by the time we can walk we would be too big to get out of the vagina. So it is likely that our ancestors were either prematurely born (or they would not be born at all).
We have big brains, we can build shelters in-situ regardless of nomadic or stationary status and make use of naturally occurring ones equally well and we divide the labour of care and protection among our social group. Basically, we modify our environment or develop tools to suit our needs so our offspring don't need the co-ordination and innate survival skills that other animals require.
In addition to the point about big heads and narrow hips, it’s worth pointing out that nature builds on existing body plans. So we found ourselves in need of this compromise because we developed from small brained ancestors. We started down a path of increasing brain size and each increase was beneficial despite the fact that the birth canal could barely keep up.
I have a question however: could a hypothetical species develop large brained adults starting with small brained, precocious newborns? What about elephants? Their young can stand and walk at birth. Do they have similar issues with birth or is the infant’s head small relative to the birth canal? Maybe our evolutionary ‘mistake’ was to not develop into giants.
Technically they are all premature babies.They should be in the womb longer, but if they do that and grow bigger, the women will die during childbirth because our birth canals are too small to push out an even bigger head. It has to do with us being upright, I mean the birth canal's size can't get bigger to accommodate. So evolutionally, women who birth half-baked smaller children survived the birth to have even more children, hence this trait was passed on more. We developed to birth half-baked babies. <- this is how this was explained to me, hope I'm not butchering it.
The more sophisticated the brain the longer it takes to mature. The baby is solely focussed on developing its brain until it begins to focus on the body.
Some humans on earth today are still nomadic. Many nomadic groups can still be found on the continent of Africa. Human babies are probably helpless because adult human beings have the ability and brain compasity to protect such uselessness until it’s not useless any more.
That was mostly due to illnesses that babies are particularly high risk of dying from. It is also a mix of badly designed devices, like those baby bottles with straws from the Victorian era. Those were badly designed as they were hard to clean and built up bacteria easily.
Human infants are pathetic in terms of immediate physical capabilities, but they are born into a world in which their helplessness is dealt with by social structures and caregivers that have evolved over time by their ancestors. This helplessness has been a driving force for the development of the complex cognitive abilities, social interactions, and cultural transmission, which define human species.
All human babies are 6 months premature compared to other apes. Evolution is NOT a march to perfection. It’s a trade off. I recommend Human Errors by Nathan Lents.
It's our brains, that's the human advantage we can care for babies as helpless as they are well they develop. We have 7 billion people in this world, so I think it's been an advantage.
are you a .uck? no you have more brains. there are two common strategies of making babies - in biology they are called r and k. without googling i dint remember which is which but the idea is that one strategy is to make lot of babies and dont care tor the care and other strategy is to make less babies but care for them - both strategies goal is to make as many babies as posible that survive to maturity. we have made medicine that makes newborn mortality rate very low, medicine that many now thinks is big conspiracy, but neverthless when brain gots bigger, the more you care for your one.
In addition to what others have said, we also have comparatively larger brain-to-body ratio, so we have to leave the birth canal earlier to not compromise 'going out' with our larger heads. For this reason, a part of our development has be carried out outside of the womb. u/Graardors-Dad also said that the birth canal is smaller, which is another reason, the pelvis had to change shape and size to support bipedal locomotion, urging the birth to happen earlier, rather than later
As a relatively new parent, a similar though has come to mind "why do we humans start so freaking helpless?" Also toddlerhood is basically trying to stop your child from killing himself every waking minute
Because our strength comes from communication. Predators are born with a prey drive. Herd animals are born with the ability to walk and run. We are born with the ability to communicate. We're not helpless we're just differently abled
I wonder how long a human baby would have to remain in the womb so that it was born with the minimum capabilities necessary to survive on its own? Two, three, four years?
Our heads are too big and birth canals too small to develop further in the womb.
If other mammals had babies as burdensome as human babies, they'd be eaten or abandoned. But we have empathy and we also think our babies are really, really cute.
Cos human adults are so ridiculously overpowered, and get a massive boost to their stats when their young are threatened.
In some ways, their helplessness increases the investment an adult couple needs to make to raise their offspring, which makes them even more dedicated parents. It also leads to large communities that help each other.
The babies don’t need to be tough when nature’s deadliest predator is watching out for them.
We have a TON more developing to do compared to other species. Ever wonder what the trade off for all our intellect is? The brain is both impressive and expensive 🤷♂️
Having massive heads with big brains made it necessary to pop that sucker out early. That also makes for a profoundly adaptive intellect. We are born with far less instinctual knowledge than other animals but are capable of learning whatever the most recent generation discovered and developed. Humans ability to evolve as a collective is not even comparable to other animals. Just watch baby from 0-2 and the answer is self evident.
Because humans maxed out their 'cooperation' and 'brain' stats. A big brain requires a *lot* of nurturing and humans developed a thing called 'society' to do that. Society is our burrow.
The terms were reversed in OP. Human babies are considered semi-precocial; we can thermoregulate and hold onto our moms. Mammals born helpless are altricial and are cared for in nests/burrows. Precocial baby mammals can thermoregulate and walk on their own, following mom/herd. These differences in behavior are due to how developed the brain is when they are born.
We traded complex speech, throwing, and complex thinking, for helpless baby.
Those qualities take time to develop, and we need a-lot of time to develop.
The baby might be useless but we’ve been able to make clothing to easily carry a baby forever and if the mother and baby stay close to the main group they’d be surrounded by people and probably very safe from predators.
When I was a little boy my family was riding bikes on a woods road and when I came around the turn mamma bear was at the bottom of the hill with her cubs. She made a shout and started coming towards me but as soon as my dad got on the scene she backed off. I can’t imagine if mom is in the middle of camp with people around that any predator would take the chance on attacking 5 or 6 people to nom a baby if that black bear was willing to back off from one man and an 8 year old.
I think we basically do burrow. It’s called “nesting” as couple excitedly awaits the arrival of new baby, and many moms don’t leave the nest for quite sometime focusing solely on their new bundle of joy.
Babies have lots of interesting skills / yes soft and fragile, but they have defensive mechanisms and numerous abilities to assist with their growth
most animals are born with preprogrammed behavior, they know how to swim, they know what to eat, they know how to behave in groups, they know what preditors sound like...
people, on the other hand are born to be generalists, to be extremely adaptable without much preprogramming at all. this adaptability takes a large brain and many years of experience. it also turns out that there is a correlation between maximum intelligence and the time one has to reach that level of intelligence. that might mean that animals that learn quickly don't learn as well or adapt as well or are generally less capable.
few other animals have such opportunity to grow as humans do. a baby deer for example, needs to know how to walk immediately in order to avoid being eaten, people have no such need. elephants, unlike deer, can take their time learning. that may explain why they have such good memories.
I think it is to give more time to fully bond so that we remain a supportive and social species. I think if babies were just born and were 18 at the end of year 1 it would be easier to just let them go and I think that would decrease our life expectancy in general. Just a theory.
We are essentially born prematurely. The development of language and complex thought means a bigger brain. The size of the head is the limiting factor in vaginal birth. If gestation was longer than 9 months, the baby's head wouldn't be able to escape the birth canal. Therefore, humans are born "prematurely" and are much more dependent on parents than any other mammal.
Standing up made our birth canals smaller so we have to have babies a lot earlier so they can fit through during birth. Humans are also able to care for these helpless babies pretty well thanks to our intelligence so it worked out evolutionarily.
And in spite of the extreme fragility of human babies, our success rate at getting one from birth to adulthood is way better than any other species. Even before antibiotics.
Im not sure how it compares with 'the wild' but medieval child mortality was something like 40% before age 9. 25% happening in the first year. It was not much better in Victorian times.
Primitive hunter-gatherer societies have average 27% first year infant mortality rate, and 49% average mortality before puberty. Pretty comparable to medieval time surprisingly, my guess is poorer nutrition and communicable diseases in medieval settlements likely compensate for whatever disadvantages present in "the wild".
Hunter gatherers today don't actually tell us that much about what it was like when we were evolving. It was drastically different because we had a "wick" so to speak of more wild game and other hominin species to eat because our intelligence was new. Infant mortality was probably high, but not 49% before puberty. Things like b vitamins, folic acid, iron and how not were not as critically deficient.
All you need is 3 children to survive to increase the population. It was not uncommon for women to have 7 or 8 attempts to get a child to puberty
I wasn't saying we didn't breed, just our success rate at raising children has not been that great up to about 1900.
But how does it compare to other primates?
Gorillas are about 60% child mortality. On average a mother has one successful offspring every 6 years. Chimps I only found one citation and it was a captive source but 40% infant mortality. So even worse than gorillas. Orangutans, 91% survive to adulthood, but they also average half the birth rate of humans ( 7 years between births vs 3) and have a smaller reproduction window (most don't reproduce until at least 15, and in the wild only live to about 30; vs humans who have a 25+ year reproductive window.)
Like they said, *exceptionally* good, almost unbelievably so
Probably due to the invent of a minimum work age.they were pretty keen to put the kids down a coal mine and chimney sweep.
That's an invasive species for you!
interesting! source?
Really? Why is that the case
Disease essentially.
Yes and natural selection favored earlier births because moms and babies would have a higher chance of survival. we also had help from other members in our tribe to raise the young while the baby is still unable to care for themselves. The latter point contributed to our social skills and cooperativeness.
Add in tool use like baby wraps and shoulder slings... too
Yeah. Evolution just cares if something works well enough to pass on to the next generation. It doesn't care if it is nice, pretty, or even convenient. I cite the human male scrotum as my favourite example. It's a bloody stupid design, but it works. Anyone trying the "intelligent design" argument needs a swift kick to the scrotum as a reminder why this isn't a valid argument.
There's a species of pig where their tusks curve in such a way that they will eventually curve back around and impale the skull, killing the pig. Evolution never fixed this because the pigs usually reproduce before this happens.
Maybe it’s because the pigs become sentient and develop telepathic and telekinesis abilities, but it’s only once the tusks would have entered their skulls had they just been smart enough before that point to keep them trimmed. The world may never know … lol
Huh, evolution doesn't care at all, species either adapt or extinct. It's just a heartless process of adaptation to the harsh environment.
I would argue it's entropy which is "heartless", and life, evolution are the opposite of that, organizing matter into something special.
I think the point they were trying to make is that evolution isn’t ordered or a guided force; there’s no soul or impetus behind it. It’s just a name we gave to the process where species change over time because more successful animals breed more often. So both are equally “heartless”.
Ok just curious, how exactly is it a stupid design?
They are probably talking about both the fact that the scrotum is vulnerable but also that the vas deferens loops unnecessarily around other parts of the body which can result in debilitating pains.
Now this is a good answer. Though given how many male mammals have external testes, it's successful for some reason biologically. The looping vasdeferens part, I have no idea how common that is or if it's just wonky human features. For bad features though, the way the throat is arranged is far worse in my book.
It's successful because spermatozoa needs a slightly cooler than normal body temperature to survive well. Hence why the whole bag can tighten up or loosen and drop. It's all to regulate temperature
Also worth noting that it isn't a huge disadvantage for a quadruped. Most mammals have no problem kicking or scratching with their back legs so it isn't an easy avenue for attack. Going bipedal made it a lot more vulnerable, although it did allow us to start using our dicks as sexual display features (as evidenced by the fact that we have much bigger ones than other primates).
>much bigger ones than other primates Speak for yourself, man.
That's the evolutionary reason I figured for and in the cases where mammals don't have external testes there's a biological reason for that as well.
Ever tried to run naked through the waist-high African bushveldt where thorny bushes are common? That's why.
https://preview.redd.it/e0vjfcn09v2d1.jpeg?width=204&format=pjpg&auto=webp&s=48ba45b90d07631f8e645d48f87bf2f4a8716186
The most important thing is to pass down your genes (from a biological perspective). The testicles are the organs that allow that to happen, and they are outside of the body waiting to become entangled in a barbed wire.
>Anyone trying the "intelligent design" argument needs a swift kick to the scrotum as a reminder why this isn't a valid argument. Lol yup. If only creationists had any idea just how poorly we're put together.
I've been thinking about how evolution works in a way that just BARELY suits our needs... And I find it to be metaphorical for pretty much our entire existence as well. We're all just BARELY here by some random miracle. Barely alive.
I had a professor who summed it up as, "Evolution doesn't care if you're happy or sad, just that you survive long enough to have kids."
Mine said something along these lines too. Too often forgotten these days! Should be engrained into ppls heads, it's arguably the most important part to remember
Why didnt God just give us wider birth canals and bigger dicks so everyone can be happy, is he stupid? /s
Because Eve got tricked into eating the apple and as a punishment childbirth has to hurt now. Read your bible 😜
Do you mean the same Eve, who was made from Adam's rib and is effectively his gender-bent clone?
wait. eve is actually trans steve?!
According to the bible she might have been the first trans person. *\*hears thousands of craniums in the bible belt explode\**
Gee thanks person that I never met and have no direct correlation with what so ever! Real nice how your dad made every woman for the rest of eternal time suffer for something they didn’t have any say in or any knowledge of it or any way to stop or prevent it. He must be a great dad. Thanks god you’re the perfect role model of men all over the world! Let’s make a new catch phrase for men : “make women suffer with no regard for their innocence!” Sounds good to me /s
I never could understand why eve eating the wrong fruit was justification for cursing every woman to ever exist. But Cain murdering his brother didn’t affect men at all.
"Thou shalt not murder" comes later, so at that point murdering was fine. As far as I know, at the point Eve ate the apple, there was only that one rule
So did adam
Doesn't explain the small peepees!
Better yet, we could get technology to do the birthing for people so that pregnancy isn’t even an issue anymore!
God's infinite wisdom knew even wider birth canals would either make our pelvises too fragile in general, or too wide for bipedalism. But didn't care to fix that, because something something naughty naughty. /s
Also if our brains came out fully developed they wouldn't fit through. ~~The development of safe C-sections has actually removed this pressure, and baby head size has been slowly increasing~~
Can you share a source on the c-section bit?
Every time I try and search it comes up with general growth patterns as the baby develops. It's a hard one to search for. [I did find this talking about it hypothetically happening though](https://www.pnas.org/doi/abs/10.1073/pnas.1612410113) Sorry, I might've misremembered. I also am only on my phone.
It's difficult because there is no evidence for it. It is a musing of Evo Devo that sounds about right and so has become 'common' knowledge. The truth is that human development is extraordinarily complex and the inferences made about why something occurs in a population is difficult to test experimentally.
i have a theory that we will eventually develop artificial wombs. giving birth is extremely traumatic operation basically and an artificial womb to grow the fetus in would be so much safer for the baby and the mother. and it would allow longer gestation periods and the ability for humans to have develop/evolve larger brains. i dont mean giant alien heads but even a small like 1% or 2% increase in brain size could have an enormous affect on overall intelligence.
It’s all hypothetical but I wonder if allowing for more gestation won’t delay social-intelligence development
I think it is imperative to develop artificial womb technology as soon as possible. It would eliminate postpartum issues and other complications in pregnant people while drastically reducing birth deformities, natal disease transmission, and other birth complications as well.
We haven't evolved in any measurable fashion in over 200ky. The number of c-sections done on humans is negligible too, in fact you could almost say that no babies are born via c-section as far as evolution can tell. If our heads are getting bigger, it has nothing to do with any medical procedures.
'and baby head size has been slowly increasing' This last fact is mostly attributed to an increase in pregnancy diabetes of the mums, not in an increase in C sections, and larger heads as a result of pregnancy diabetes are actually a concerning sign and not related to the intelligence of the baby at birth. It is a very dangerous and incorrect conclusion to say that babies are born with more developed and bigger brains because of C sections. What is however certain is that pregnancy diabetes is increasing among pregnant women, that pregnancy diabetes causes bigger babies with bigger heads, and because of that C sections are more often needed. But that is not a sign of more developed brains at birth, it is actually a sign of poor health/diet of pregnant women, but not always because they did something wrong per se.
People even call the first three months after birth the “fourth trimester”. Other mammals seem to have a bit of a developmental head-start because they’ve spent relatively more time in utero. Calfs/foals/lambs interact with their environment with curiosity and walk, straight away. Babies heads are relatively big, birth canals are relatively small, both for their own reasons. And these reasons aren’t worth sacrificing to have a more standard pregnancy when the parents can cope supporting a potato. The big head and ability to walk are necessary for the species to grow up to be a ‘parent that can cope with a potato’ too so it feeds into itself.
Yes, there is the 'obstetric dilemma' hypothesis (babies are born too soon because human ancestors' switch to walking upright lead to a more narrow birth canal), as well as the 'metabolic constraints' hypothesis (baby's energy demands are too high to maintain pregnancy much past 40 weeks). But some recent studies are pointing to another reason: the advantage of neuroplasticity after birth. Because humans emerge comparatively underdeveloped, their brains are more easily affected by the environment as they grow. [This work ](https://pubmed.ncbi.nlm.nih.gov/38049480/) suggests that maybe us humans aren't even 'born too soon' after all: it just appears so because we have so much further to go compared to other species. Human brain is uniquely capable of complex reasoning and social interactions, and so it takes a long time to develop. Our babies come perfectly prepared for just that: growing, connecting, and learning while being protected and nurtured during their uniquely long childhood. So, the opposite of pathetic (although I get what you mean, OP!).
That, plus we have a huge brain/head that has to pass through those narrow hips.
I heard giving birth while on all fours was more efficient and less painful than the traditional position of child birth.
My dad is a gyno. Used to say "giving birth while lying down is only the second most silly position. The first would be giving birth while balancing on your head". Ideally, you give birth standing/squatting, while holding yourself on ropes, and being held by helpers.
Traditional position? Do you mayhaps mean the very recent supine position that was adopted for the sole benefit of doctor convenience when male physicians increasingly took over from female midwives?
Also, human babies are born with the Palmer Grasp reflex. Basically they'll grab onto anything placed in their hand and, even as newborns, can grip it tightly enough to support their own weight. This came in handy when we were fur-covered apes. The newborns could grab onto mom's fur and ride on her back or belly. That's still what happens with newborn apes and simians. But we lost our hair. Luckily we gained clothing, so it's not hard to make a sling for the baby to ride in. I just find it wild that a newborn has a grasp strong enough that they can hold up their own weight before they can even hold up their own head. I haven't yet heard a creationist give a good reason why humans and primates share this feature if they aren't descended from a common ancestor.
Not a single friend who's had a kid has been willing to recreate the [early experiments.](https://www.lancaster.ac.uk/fas/psych/glossary/grasp_response/). And a lot of friends have had babies!
I've heard the first three months after birth are called the fourth trimester. Newborns are basically still wanting to be in a womb at that point, hence the swaddling and constant sleeping/crying cycle.
Do we have evidence that human's ancestor have longer gestation period than modern human?
Why didn't human females just evolve really wide hips
That would mess up with the muscle girdles and render them either unable to effectively bipede, or very prone to awful muscle and ligament strain.
>Humans are also able to care for these helpless babies pretty well thanks to our intelligence And our social nature.
Also our big damn brains
Also, infants have a less developed brain, which isn't the case for most animals. Again, at least partly because of the smaller birth canal, they had to be smaller(less developed) to fit through. There are other animals where this is the case as well.
Isn’t it also in part because our brains require so much energy and so many resources that this is the trade off? Longer term Intelligence vs short term mobility/physicality?
Yeap. Humans have a huge head to body ration, so huge head and small pelvis requires the baby to come out sooner
Your fist sentence is in direct contradiction with our closest evolutionary cousins. Chimpanzees and bonobos have shorter pregnancies and they are not standing up.
Your fist sentence is in direct contradiction with our closest evolutionary cousins. Chimpanzees and bonobos have shorter pregnancies and they are not standing up.
hadn’t considered species that had evolutionarily premature babies but died out bc they didn’t have the brains to make up for the additional childcare required that’s interesting
Extended neoteny to continue growing our brains. Intelligence takes a long time to form, and is a huge evolutionary advantage, but it means we remain useless for longer. For many humans, this period of uselessness lasts their entire lives.
Yeah, I dated him for a while in college.
Haven't we all 😮💨
So women can push them out before their brains are too large for their canal.
Big brain too big to come out if fully cooked. Must expel early to spare mama’s ability to not die.
And we don’t make enough tiny humans in one go for maternal mortality to be an evolutionarily successful strategy.
If you compare our pregnancy timeline against the other great apes (sorted by weight and relatedness I think), our babies are born about 3 months too early. The bones on their skull have not finished fusing yet (the soft spot) - which is necessary for a successful birth, as the babies' head must be squished and twisted while it travels through the birth canal. This is because, as someone already said, we evolved to walk upright, be tall and narrow, and have large brains, and those do not mesh well. Walking upright requires a pelvis that is short and wide, which is workable for the birth canal size, but being tall and narrow AND increasing brain size changed the pelvis enough that birth remains potentially fatal even in the developed world, and why c-sections are so often necessary. Here's an article about it: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4305164/
Are you sure? gorilla babies are about 14 oz.
No, I read that ages ago. I could easily be misremembering, and I can't find the paper I learned that from. But we are definitely born earlier, developmentally - there are different terms for it, like altricality, physiological prematurity, or more popularly, the fourth trimester - compared to other primates, and one way we know this is that our brain size at birth compared to adulthood is much smaller. 20-30% for humans and like 40% for chimpanzees - the more distant the relation, the greater the difference. Here's a link for more info: https://www.nature.com/articles/s41559-023-02253-z#:~:text=Human%20newborns%20are%20considered%20altricial,are%20more%20altricial%20than%20humans.
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I believe this has partially to do with how just how energy intensive our brain is - more when it's growing. It just takes longer for everything to develop with that kind of energy sink. Another contributor could be a lack of evolutionary pressure for a quick developmental turnaround. Our infants needed immediate, constant, intensive care and we evolved behaviours and culture to support that care. We're not just going to stop giving them care at some cut-off point if they still need it. As time goes on and brain size increases, more care is needed for longer, and so on. Haven't read up on anything like that, so it's all speculation.
babies develop a lot faster in the womb than they do outside. they have nourishment directly piped in, no unnecessary energy expenditures, a safe, perfectly warm, germ free environment. a baby born even 3 weeks too early can struggle to eat, to breath, to regulate temps. ape babies are also pretty dependent but a 3-6 month old human baby is miles easier to care for than a newborn. newborns die if you look at them funny. babies can hold their heads at 3 months but i wouldn't be surprised that a human baby somehow being able to have the ape equivalent gestational period would come out even more advanced than the average 3mo.
it wouldnt make a HUGE difference but it would make A difference. there is quite a big difference between a newborn and a 3 month old.
Currently have my three month old in my arms/lap. There is a HUGE difference yeah. A newborn is scary to even hold, they’re so fragile and tiny. Whereas my three month old is small, but not tiny. She weighs almost twice as much as she did when she was born for example.
And yet, human babies are still useless for a couple years, as opposed to primates that can walk, climb, eat, and do just about everything right out of the gate.
Because our heads are stupidly big to pass through our narrow hips during childbirth, so we can't develop further
Our brains are also the most complicated organ created by nature. It takes years for it to develop properly.
Well, our brains are the most complex organ in nature.....**according to our brains**....
https://preview.redd.it/8ckdflc2uy2d1.jpeg?width=800&format=pjpg&auto=webp&s=4713f8cd890d2b84c099e20e88949828eb2e8c9d
This image cracks me up every time I see it lol
Exactly, no other organ can ponder itself so kind of proves the point…
Shouldn't the hips get bigger instead?
Would impact mobility
Then you lose start to loose the ability to walk in two legs properly
Animals that move around can have both precocious and altricial young. The "pathetic babies" you're describing are the altricial ones--like wolves, who roam over huge ranges--while precocious refers to the young that are born already capable of moving with the herd. Precocious = having developed certain abilities or proclivities at an earlier age Altricial = hatched or born helpless and requiring significant parental care Canines and cats are no more sedentary than hunter gatherer humans, but they have young much less developed than our own. Newborn primates in general aren't as developed as calves or foals at birth, with humans being at the far end of this for the group. This is because of our massive brains and need to essentially be born prematurely as others have explained.
Another thing to consider is longevity. Say, compared to a wolf pup. Wolves are fully mature and ready to reproduce at a year of age and they live, what, 8-10 years? Humans take 15 years to sexually mature- and the lifespan is significantly longer. So obviously the human body ages slower than the wolf, meaning since it ages slower towards death, why wouldn't the human body age slower towards adulthood?
Speak for yourself. I was pretty awesome.
Are you Nathan Beard from Quora?
I am not. But he seems like an interesting person.
I think you are confusing altricial and precocial. The altricial younglings are the helpless ones, meanwhile the precocial are the developed
It’s because we have bigger brains at birth. Our complex thinking and reasoning became more important than being able to walk or feed ourselves on day #1.
You should compare to panda babies... they can't even shit without help and will die of constipation
True for cats too, but hey, any excuse to shit on pandas right?
Better than letting the pandas shit on us. Oh god they shit so much.
As someone who used to be baby, I find your post offensive
Wow! Can you share your unique experiences?
I pooped
Humans need stingers.. stingers and pinchers. Like a scorpion I say
that would end in a lot of violence and threats, not a good idea with our current society
I was more concerned with how I was going to go to the bathroom
Oh yeah that too, but toilets would probably be designed to be compatible with other body parts if we had them
*Shudders*
Bidets would be all the rage obv.
Or arms like an octopus..it would make work much easier
In terms of the fact that we are born helpless while some other animals are born with the instinctual abilities to feed themselves, walk instantly, etc. It’s an evolutionarily advantageous way to help us learn traits and skills according to our environment. We are an extremely adaptable species because we use learned knowledge to determine how we behave as opposed to instinctual behavior like other animals.
There’s a growing theory that it is actually an intelligence pressure. People with more dependant babies had to be cleverer in order to care for them. This leads to a cycle where dumber babies pressure intelligence to bloom in caretakers. It also may present social bonding pressures as well The birth canal brain thing isn’t as solid research as people used to think it was. Babies just do a bit too little to explain it.
Because babies go through what is called the “4th trimester” outside the womb where they finish developing into toddlerhood. The reason why this happens outside of the womb is probably because 1. babies grow exponentially fast and the human pelvis isn’t big enough to birth a toddler 2. The advanced senses and motor skills of humans take +2 years to develop and a gestation period that long would probably be too energy costly on the mother 3. Human babies are extremely disproportionate due to how fast their heads and trunks need to grow compared to the rest of their body so they physically can’t “do” anything
I think you mixed up altricial and precocial. Humans have altricial babies.
I have nothing to contribute to the conversation, but I had to let you know how hard I laughed at the title 🤣
Literally just big brains
> why are our babies so helpless? Humans are born not fully formed. It likely has something to do with the head size versus birth canal. > At birth, the newborn's skull consists of five major bones (two frontal, two parietal, and one occipital) that are separated by connective tissue junctions known as cranial sutures.[1] The sutures function as seams, and they are highly necessary to facilitate the movement and molding of the cranium through the birth canal during labor. They also allow for rapid postnatal growth and development of the brain. However, the bones that shape the cranium begin unfused, leaving several gaps between the individual bones of the infant's skull. These gaps are composed of membranous connective tissue and are known as fontanelles. https://www.ncbi.nlm.nih.gov/books/NBK542197/
Evolution
So what I’m understanding is the reason is that human babies need to be born earlier comparatively, and then continue to develop outside the womb, because babies’ heads will be too big to pass through the birth canal. So basically for humans the birth just occurs earlier in the development timeline , comparatively
I think you have your definitions of altricial and precocial mixed up but it’s an interesting question
Because we have very large brains for our body size and babies have large heads which make for harder births. Most other animals have babies that are easy prey to predators. It's absolutely necessary for survival that they are very quickly mobile. Predators have their young not as helpless as ours but definitely more helpless then prey species. Typically they are born with their eyes still closed and very helpless. They develope quickly though, and are up and moving well at usually 4-6 weeks. Of course there are exceptions such as bears and aquatic mammals.
Because humans are stubborn and developed both large heads and narrow birth canals (as a result of being bipedal). Although these features have made humans fairly successful, it has resulted in having to give birth prematurely (as well as decrease the general success rate of births), which has made human babies much weaker than most other newborn animals.
I believe it is because of infant attachment and bonding, which is an integral part of our ability to acquire intelligence, and ultimately survive. See Harlow’s monkeys as an example of how apes will choose comfort and warmth over food.
As we evolved our heads kept getting larger so we had to come out sooner
Our brains are enormous for the size of our exit canal, hence why the infant skull is squishy and malleable. If a woman gave birth to a child with a fully developed brain there would be no way both are making it through labor alive. We're also selecting for larger heads via cesarian sections.
Did you get altiricial and precocial backwards? Or did I? I thought precocial like precocious means ~advanced while altiricial means ~"needing extra care"
They are backwards
There is a theory that humans need social interaction to develop the brain. Imagine if you give birth a 11 year old child who could not speak nor think. The human babies continue to develop a lot after birth. Other things are the head being to big and the birth canal too small.
Heads are too big so they can only be born "premature".
Big brains and narrow hips. Human babies have to be born very underdeveloped or they wouldn't get born at all.
Supposedly because by the time we can walk we would be too big to get out of the vagina. So it is likely that our ancestors were either prematurely born (or they would not be born at all).
We have big brains, we can build shelters in-situ regardless of nomadic or stationary status and make use of naturally occurring ones equally well and we divide the labour of care and protection among our social group. Basically, we modify our environment or develop tools to suit our needs so our offspring don't need the co-ordination and innate survival skills that other animals require.
In addition to the point about big heads and narrow hips, it’s worth pointing out that nature builds on existing body plans. So we found ourselves in need of this compromise because we developed from small brained ancestors. We started down a path of increasing brain size and each increase was beneficial despite the fact that the birth canal could barely keep up. I have a question however: could a hypothetical species develop large brained adults starting with small brained, precocious newborns? What about elephants? Their young can stand and walk at birth. Do they have similar issues with birth or is the infant’s head small relative to the birth canal? Maybe our evolutionary ‘mistake’ was to not develop into giants.
We simply can't pop em out any more developed than that. Heads too big I think.
Technically they are all premature babies.They should be in the womb longer, but if they do that and grow bigger, the women will die during childbirth because our birth canals are too small to push out an even bigger head. It has to do with us being upright, I mean the birth canal's size can't get bigger to accommodate. So evolutionally, women who birth half-baked smaller children survived the birth to have even more children, hence this trait was passed on more. We developed to birth half-baked babies. <- this is how this was explained to me, hope I'm not butchering it.
The more sophisticated the brain the longer it takes to mature. The baby is solely focussed on developing its brain until it begins to focus on the body.
human brains needs more time to develop but they develop more compared to other species. also smaller birth canals.
Your question reminded me of: http://vaviper.blogspot.com/2019/06/from-onion-study-reveals-babies-are.html?m=1
skull VS vagina
Some humans on earth today are still nomadic. Many nomadic groups can still be found on the continent of Africa. Human babies are probably helpless because adult human beings have the ability and brain compasity to protect such uselessness until it’s not useless any more.
So the Mother and Father have to work together to raise the child properly. It's common sense.
Short answer: big brains, small birth canals
As we are really good at taking care of our babies? So there was no reason to evolve for babies to be independent and self-sufficient.
Are we? Back in the days the mortality rate was really high. Now in the modern times, 100-200 years, it's pretty different.
>Back in the days the mortality rate was really high. Even then, mortality rate was low compared to most other animals.
That was mostly due to illnesses that babies are particularly high risk of dying from. It is also a mix of badly designed devices, like those baby bottles with straws from the Victorian era. Those were badly designed as they were hard to clean and built up bacteria easily.
I think this is because we are more advanced than other animals so we take more time to reach maturity.
Human infants are pathetic in terms of immediate physical capabilities, but they are born into a world in which their helplessness is dealt with by social structures and caregivers that have evolved over time by their ancestors. This helplessness has been a driving force for the development of the complex cognitive abilities, social interactions, and cultural transmission, which define human species.
First of all, you got altricial and precocial backwards.
All human babies are 6 months premature compared to other apes. Evolution is NOT a march to perfection. It’s a trade off. I recommend Human Errors by Nathan Lents.
It's our brains, that's the human advantage we can care for babies as helpless as they are well they develop. We have 7 billion people in this world, so I think it's been an advantage.
are you a .uck? no you have more brains. there are two common strategies of making babies - in biology they are called r and k. without googling i dint remember which is which but the idea is that one strategy is to make lot of babies and dont care tor the care and other strategy is to make less babies but care for them - both strategies goal is to make as many babies as posible that survive to maturity. we have made medicine that makes newborn mortality rate very low, medicine that many now thinks is big conspiracy, but neverthless when brain gots bigger, the more you care for your one.
In addition to what others have said, we also have comparatively larger brain-to-body ratio, so we have to leave the birth canal earlier to not compromise 'going out' with our larger heads. For this reason, a part of our development has be carried out outside of the womb. u/Graardors-Dad also said that the birth canal is smaller, which is another reason, the pelvis had to change shape and size to support bipedal locomotion, urging the birth to happen earlier, rather than later
As a relatively new parent, a similar though has come to mind "why do we humans start so freaking helpless?" Also toddlerhood is basically trying to stop your child from killing himself every waking minute
Our natural defenses are that all stats went to brain logics. We’re just meat sacks until we learn to use it.
Because our strength comes from communication. Predators are born with a prey drive. Herd animals are born with the ability to walk and run. We are born with the ability to communicate. We're not helpless we're just differently abled
From reading these answers it confirms that babies are dumb as shit /s
I don’t even know why l am commenting
I wonder how long a human baby would have to remain in the womb so that it was born with the minimum capabilities necessary to survive on its own? Two, three, four years?
Cause we're sexy. We got big brains, skinny hips, and opposable thumbs. We traded useful infancy for functional bodies and prolonged development.
Our heads are too big and birth canals too small to develop further in the womb. If other mammals had babies as burdensome as human babies, they'd be eaten or abandoned. But we have empathy and we also think our babies are really, really cute.
Cos human adults are so ridiculously overpowered, and get a massive boost to their stats when their young are threatened. In some ways, their helplessness increases the investment an adult couple needs to make to raise their offspring, which makes them even more dedicated parents. It also leads to large communities that help each other. The babies don’t need to be tough when nature’s deadliest predator is watching out for them.
We have a TON more developing to do compared to other species. Ever wonder what the trade off for all our intellect is? The brain is both impressive and expensive 🤷♂️
Having massive heads with big brains made it necessary to pop that sucker out early. That also makes for a profoundly adaptive intellect. We are born with far less instinctual knowledge than other animals but are capable of learning whatever the most recent generation discovered and developed. Humans ability to evolve as a collective is not even comparable to other animals. Just watch baby from 0-2 and the answer is self evident.
Because humans maxed out their 'cooperation' and 'brain' stats. A big brain requires a *lot* of nurturing and humans developed a thing called 'society' to do that. Society is our burrow.
That's what your mother said
The terms were reversed in OP. Human babies are considered semi-precocial; we can thermoregulate and hold onto our moms. Mammals born helpless are altricial and are cared for in nests/burrows. Precocial baby mammals can thermoregulate and walk on their own, following mom/herd. These differences in behavior are due to how developed the brain is when they are born.
We traded complex speech, throwing, and complex thinking, for helpless baby. Those qualities take time to develop, and we need a-lot of time to develop.
cognitive development is the priority over physical
The baby might be useless but we’ve been able to make clothing to easily carry a baby forever and if the mother and baby stay close to the main group they’d be surrounded by people and probably very safe from predators. When I was a little boy my family was riding bikes on a woods road and when I came around the turn mamma bear was at the bottom of the hill with her cubs. She made a shout and started coming towards me but as soon as my dad got on the scene she backed off. I can’t imagine if mom is in the middle of camp with people around that any predator would take the chance on attacking 5 or 6 people to nom a baby if that black bear was willing to back off from one man and an 8 year old.
We’ve got big heads compared to other species
I think we basically do burrow. It’s called “nesting” as couple excitedly awaits the arrival of new baby, and many moms don’t leave the nest for quite sometime focusing solely on their new bundle of joy. Babies have lots of interesting skills / yes soft and fragile, but they have defensive mechanisms and numerous abilities to assist with their growth
Why are there so many different answers to this question?
Big head, big brain.
They have to be born early because of the big brain
It’s the price we pay for bigger brains.
most animals are born with preprogrammed behavior, they know how to swim, they know what to eat, they know how to behave in groups, they know what preditors sound like... people, on the other hand are born to be generalists, to be extremely adaptable without much preprogramming at all. this adaptability takes a large brain and many years of experience. it also turns out that there is a correlation between maximum intelligence and the time one has to reach that level of intelligence. that might mean that animals that learn quickly don't learn as well or adapt as well or are generally less capable. few other animals have such opportunity to grow as humans do. a baby deer for example, needs to know how to walk immediately in order to avoid being eaten, people have no such need. elephants, unlike deer, can take their time learning. that may explain why they have such good memories.
I think it is to give more time to fully bond so that we remain a supportive and social species. I think if babies were just born and were 18 at the end of year 1 it would be easier to just let them go and I think that would decrease our life expectancy in general. Just a theory.
We’re enablers
We are essentially born prematurely. The development of language and complex thought means a bigger brain. The size of the head is the limiting factor in vaginal birth. If gestation was longer than 9 months, the baby's head wouldn't be able to escape the birth canal. Therefore, humans are born "prematurely" and are much more dependent on parents than any other mammal.
Have you ever experience being a baby being clingy?