Comment by somenameforme
4 days ago
One of the most curious things I learned about babies is that they are born with a walking instinct, long before they actually can walk. If you hold them up, they will move their legs in a perfectly correct walking fashion. But they lack the strength and agility to keep their body up. At around 3 months this walking instinct disappears, and then at around a year we 'relearn' to walk when we have the strength and agility to hold ourselves up.
But if we were on a planet with significantly lower gravity, humans would likely be walking very near immediately.
One of my kids could stand on the day she was born. She seemed super strong, so while I held her I just took my hands away, and she stood there and stared at the rest of the family. Lasted a good 10 seconds, then I thought it was enough.
My boy is 2mo old and he could lock his legs with extreme strength in the first few days. I was very impressed, but my wife told me to stop letting his legs hold any weight. Apparently his uncle was walking at 9mo but his body wasn't ready and he gave himself a hernia.
According to my wife, who is an OT, children are born with a reflex that straightens their legs and which sounds similar to what you saw.
She said they lose the reflex during their first year, and then develop the actual skill of standing separately.
It was fun to watch with our kids, too!
Is this separate from the prenatal kicking? Or just a continuation of it?
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Babies have strong legs in order to push themselves out of the womb
>> One of my kids could stand on the day she was born. She seemed super strong, so while I held her I just took my hands away, and she stood there and stared at the rest of the family. Lasted a good 10 seconds, then I thought it was enough.
Probably a good experience. However, at that age it may have been a setback if the kid fell down and got hurt because they weren't strong or coordinated enough. The experience (good or bad) of doing something for the first time can be very influential on future behavior.
If we were on a planet with significantly lower gravity, walking would be much more difficult. Notably, on flat ground we absolutely must have an upward component to our application of force with the surface - this is clearly seen in videos taken on the lunar surface during the Apollo missions. This baby on a hypothetical lower gravity world would find standing easier, yes, but not mobility. At least not once he's taken his first few trail steps.
If gravity were lower we would have evolved differently, walking would have adapted too. On the other hand babies probably wouldn't be able to walk either. Being mobile, defenseless, and not having "runaway!" as the default defense mechanism (like horses) is an evolutionary dead end.
Sure we might have evolved differently. But that doesn't mean that the human body doesn't work better at sustained 0.8G or 1.2G or whatever.
Problem is we don't have any good data about which gravitational accelerations would be suitable for long term health. We have 1g as our baseline, and we know that months in 0g messes you up and longer is a bad idea. We don't know anything about the long-term effects of living in Mars or Lunar gravity though. It could be studied using von Braun stations, but nobody has done it.
The moon has very little gravity bringing extra problems, but maybe Mars would have the right gravity to enable Babies walk from the beginning?
If you enjoy this kind of speculating you might like the Expanse series of books and TV shows.
They have humans growing up on Mars, the asteroid belt, moons. Anyone who doesn’t grow up on earth cannot go there without extreme gravity training.
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Walking would probably suck on such a planet and we would see babies bounding long distances instead!
IIRC they also have a swimming/diving instinct/reflex, which they similarly seem to unlearn after a while.
Infants will also grip anything you place in their hands.
They will also grab with their toes. Place your finger across their toes between the foot and the sweet little toesies and they will grip your finger pretty hard. We monkey