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Okarin
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I feel like some of the answers miss that this question actually works in reverse.

Why did our - and most animals' - eyes evolve to see EM radiation specifically in this range of frequencies? Because that was the most useful and practical one to focus on as a way to get information about the environment. It just so happens that it's the "just right" EM frequency range for most solid matter to interact with it in some way, and the one provided abundantly by the Sun for everything to reflect, so it was very useful. Infrared is the other one that could be even more useful, as everything emits it, and some animals do have limited infrared detection capabilities, but the downside there is that your own sensor organ would also emit infrared (since it's just a property of things at a certain temperature), so there would be a lot of noise. Good low frequency infrared cameras need to be cooled down with liquid nitrogen, that's not easy to do for a living organism.

Meanwhile, microwaves just aren't common in nature, and radio frequencies even if they were would be way too imprecise for the scales and distances living beings operate on. Lions aren't hunting plane-sized gazelles from 20 km away. On the other end of the scale, UVs aren't as abundant and the higher in frequency you go, the more dangerous things get. You could I suppose imagine some biological organism that metabolises and concentrates uranium or some other radioactive element to develop an organ that acts as a gamma emitter to use these radiation for sensory purposes. But that has several downsides. It's complicated, it's expensive, it's dangerous (high energy radiation equates cellular damage for virtually all life), and since gammas are so penetrating they are most useful in transmission, not reflection. Maybe such animals could work in packs, using each other's sources to identify what's in between them. That might be a cool idea for a speculative biology story set on an alien planet, but on Earth, light is just that much more convenient!

Consider also, now we can create glass and a few other solid things that are also transparent. Still not so perfectly non-interacting as to be invisible (the refraction gives them away), but enough to fool someone who isn't paying attention. But such things did not exist in the ancestral environment. As far as the bird that crashes into it is concerned, glass is an eldritch magical forcefield beyond its comprehension.

I feel like some of the answers miss that this question actually works in reverse.

Why did our - and most animals' - eyes evolve to see EM radiation specifically in this range of frequencies? Because that was the most useful and practical one to focus on as a way to get information about the environment. It just so happens that it's the "just right" EM frequency range for most solid matter to interact with it in some way, and the one provided abundantly by the Sun for everything to reflect, so it was very useful. Infrared is the other one that could be even more useful, as everything emits it, and some animals do have limited infrared detection capabilities, but the downside there is that your own sensor organ would also emit infrared (since it's just a property of things at a certain temperature), so there would be a lot of noise. Good low frequency infrared cameras need to be cooled down with liquid nitrogen, that's not easy to do for a living organism.

Consider also, now we can create glass and a few other solid things that are also transparent. Still not so perfectly non-interacting as to be invisible (the refraction gives them away), but enough to fool someone who isn't paying attention. But such things did not exist in the ancestral environment. As far as the bird that crashes into it is concerned, glass is an eldritch magical forcefield beyond its comprehension.

I feel like some of the answers miss that this question actually works in reverse.

Why did our - and most animals' - eyes evolve to see EM radiation specifically in this range of frequencies? Because that was the most useful and practical one to focus on as a way to get information about the environment. It just so happens that it's the "just right" EM frequency range for most solid matter to interact with it in some way, and the one provided abundantly by the Sun for everything to reflect, so it was very useful. Infrared is the other one that could be even more useful, as everything emits it, and some animals do have limited infrared detection capabilities, but the downside there is that your own sensor organ would also emit infrared (since it's just a property of things at a certain temperature), so there would be a lot of noise. Good low frequency infrared cameras need to be cooled down with liquid nitrogen, that's not easy to do for a living organism.

Meanwhile, microwaves just aren't common in nature, and radio frequencies even if they were would be way too imprecise for the scales and distances living beings operate on. Lions aren't hunting plane-sized gazelles from 20 km away. On the other end of the scale, UVs aren't as abundant and the higher in frequency you go, the more dangerous things get. You could I suppose imagine some biological organism that metabolises and concentrates uranium or some other radioactive element to develop an organ that acts as a gamma emitter to use these radiation for sensory purposes. But that has several downsides. It's complicated, it's expensive, it's dangerous (high energy radiation equates cellular damage for virtually all life), and since gammas are so penetrating they are most useful in transmission, not reflection. Maybe such animals could work in packs, using each other's sources to identify what's in between them. That might be a cool idea for a speculative biology story set on an alien planet, but on Earth, light is just that much more convenient!

Consider also, now we can create glass and a few other solid things that are also transparent. Still not so perfectly non-interacting as to be invisible (the refraction gives them away), but enough to fool someone who isn't paying attention. But such things did not exist in the ancestral environment. As far as the bird that crashes into it is concerned, glass is an eldritch magical forcefield beyond its comprehension.

Source Link
Okarin
  • 481
  • 2
  • 10

I feel like some of the answers miss that this question actually works in reverse.

Why did our - and most animals' - eyes evolve to see EM radiation specifically in this range of frequencies? Because that was the most useful and practical one to focus on as a way to get information about the environment. It just so happens that it's the "just right" EM frequency range for most solid matter to interact with it in some way, and the one provided abundantly by the Sun for everything to reflect, so it was very useful. Infrared is the other one that could be even more useful, as everything emits it, and some animals do have limited infrared detection capabilities, but the downside there is that your own sensor organ would also emit infrared (since it's just a property of things at a certain temperature), so there would be a lot of noise. Good low frequency infrared cameras need to be cooled down with liquid nitrogen, that's not easy to do for a living organism.

Consider also, now we can create glass and a few other solid things that are also transparent. Still not so perfectly non-interacting as to be invisible (the refraction gives them away), but enough to fool someone who isn't paying attention. But such things did not exist in the ancestral environment. As far as the bird that crashes into it is concerned, glass is an eldritch magical forcefield beyond its comprehension.