Assuming unchanged density of tissues, mass is proportional to volume and strength is proportional to muscle/bone cross section. According to the square-cube law[1], to keep the same weight to strength ratio under ≃20% higher gravity, body linear dimensions should be down-scaled by 1/1.2 ≃ 83%.
So I think not many generations would be necessary, given individuals with 83% the average size or smaller are a common occurrence. The trait small body size should just become more common.
I look forward to the dwarf federation gaining independance from the terran hegemony. I only hoping we perfect stasis technology in time for me to sleep a few generations and witness it.
A great question. And one fascinating but maybe disturbing thing we have seen from the ISS is the body seems to be pretty aggressive with bone decalcification in lower-G environments. I don't know if there's a corollary for higher-G, and the mechanism is orthogonal to questions about heritability, but meaningful changes happen even within the life span of a single person.
You can doubt it. If only it was possible to go to these locations in real life and verify it yourself? That's exactly what I did. I went to Dartmoor and the difference is quite noticeable. YMMV
All life is a stack of autonomic systems. My hunch is that a human in a high G environment would make a bunch of adaptations even if they were born in orbit. By 3-5 generations they might even be another species. I am sure there has been some research done on raising mice in a high-g environment.
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I'm curious how many generations of natural selection it would take humans to adapt to the new gravity assuming we had no technology to do it.
Assuming unchanged density of tissues, mass is proportional to volume and strength is proportional to muscle/bone cross section. According to the square-cube law[1], to keep the same weight to strength ratio under ≃20% higher gravity, body linear dimensions should be down-scaled by 1/1.2 ≃ 83%.
So I think not many generations would be necessary, given individuals with 83% the average size or smaller are a common occurrence. The trait small body size should just become more common.
[1] https://en.wikipedia.org/wiki/Square%E2%80%93cube_law
I look forward to the dwarf federation gaining independance from the terran hegemony. I only hoping we perfect stasis technology in time for me to sleep a few generations and witness it.
A great question. And one fascinating but maybe disturbing thing we have seen from the ISS is the body seems to be pretty aggressive with bone decalcification in lower-G environments. I don't know if there's a corollary for higher-G, and the mechanism is orthogonal to questions about heritability, but meaningful changes happen even within the life span of a single person.
Gravity strength varies all over Earth so there are areas with slightly higher than normal gravity. eg. Dartmoor. I wonder if people who live there have higher bone density? https://en.wikipedia.org/wiki/Gravity_anomalies_of_Britain_a...
I’d assume any such signal will be buried in the noise. The difference is very small.
You might be interested to know that the difference is quite noticeable! At least on Dartmoor. Walking feels very different.
The variation is about 0.7%. I doubt a human would notice anything different.
You can doubt it. If only it was possible to go to these locations in real life and verify it yourself? That's exactly what I did. I went to Dartmoor and the difference is quite noticeable. YMMV
All life is a stack of autonomic systems. My hunch is that a human in a high G environment would make a bunch of adaptations even if they were born in orbit. By 3-5 generations they might even be another species. I am sure there has been some research done on raising mice in a high-g environment.
Hypergravity and microgravity exhibited reversal effects on the bone and muscle mass in mice
https://www.nature.com/articles/s41598-019-42829-z