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by direwolf20 127 days ago
I believe during a certain age range your eyes determine they've grown to the correct size based on how well they focus, and ancestral humans mostly focused at far away things. When we spend lots of time indoors and looking at screens, our eyes adapt to this as the default focus. Since they're also evolved to look at things nearer than the default focus but not farther (since it's meant to be at infinity), this creates myopia.
1 comments
bglazer 127 days ago
That's a lovely theory, if quite imprecise in terms of the actual biology of eye development. The actually important part of science (the part that requires a lot of expertise and judgement) is figuring out how to make that an actually testable hypothesis and then whether or not its true.
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moralestapia 126 days ago
>if quite imprecise in terms of the actual biology of eye development

Explain how, please.

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bglazer 126 days ago
> a certain age range your eyes determine they've grown to the correct size based on how well they focus

A certain age -> which one? Why?

your eyes determine -> How? What molecular growth signaling pathways are involved? How do they integrate with your brain's visual processing centers and how does that relate to "how well [your eyes] focus". Is there a biomechanical signal from muscle stress or eye curvature?

How would you test this? You'd have to change this process somehow to show that the effect is real, but you obviously can't do that with humans, so you'd probably have to use mice, but their eyes are different, but how so?

Without any of this information, it's a nice "just-so" story about cavemen looking at the horizon, but not much more than that.

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direwolf20 125 days ago
You don't need to know the molecular growth pathways to test a biological hypothesis. We don't know which molecular pathways cause lung cancer when you smoke.
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bglazer 125 days ago
We absolutely do know about the molecular pathways that cause smoking induced lung cancer. It’s TP53 and RB1 mutations (among many others). There are probably more than a hundred thousand published papers about precisely this question
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