What is so special about the spectrum of the visible light? Why can’t we see radio waves or ultra violet rays?

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What is so special about visible light spectrum?

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Anonymous 0 Comments

A simple answer is that we only have 3 cones in our eyes to detect visible light (Red, Blue and Green cones) if we had more cones or receptors we would be able to. I think in the future, it’d be possible with a bionic eye.

Anonymous 0 Comments

It’s not the light that defines what we see. It’s our eyes. Other animals have different ranges of visible light.

Anonymous 0 Comments

In the most basic way, the visible light is special because it is visible. Human eyes can see it, so we called it “light”. Once we figured out ways to change near-visible light into something we could interpret (IR/UV cameras, certain types of fluorescence, etc.) we realized that there was more to light than just what we can see, so we renamed the part that was special to our eyes “light we can see” which shortens to “visible light”.

Why do our eyes interpret visible light while other frequencies on the electromagnetic spectrum are ignored? The evolutionary answer is because there was no reason for humans to see a broader spectrum; most animals that do see a broader spectrum have specialized needs. Bees use it to recognize certain types of flowers, and sea creatures need to see even when the water filters out visible light as two examples. Humans don’t have those needs.

Why don’t our eyes see a broader spectrum anyway? Because evolution is a lazy way to design a creature and it stops trying to be better the moment it is good enough to survive for a little while.

Anonymous 0 Comments

It’s sort of just based on what can be detected and what let’s life evolve in the first place.

High energy radiation like gamma isn’t so good for life as it tends to destroy cells. Low energy like radio is hard to detect since it doesn’t have enough energy to be detectable by the chemical processes our eyes use.

UV is cool, but is still energetic enough to cause problems like skin cancer. A number of animals/insects have evolved vision that hits the UV range so it’s not completely out of the question though.

Infrared might be interesting, but the problem is that infrared is emitted by anything warm. Looking at infrared cameras you can see things that are warmer and colder than their environment, but all the background is washed out. That and you are warm, so your eyeballs would be emitting their own infrared which isn’t so good. Maybe think of it like trying to see normal visible light with a tiny flashlight -inside your eyeballs.

Visible light is also available in pretty decent quantity from the sun.

Anonymous 0 Comments

It’s only a hypothesis, but the visible spectrum is the only light that is given off by the sun in large amounts, reaches the surface, and easily passes through water (which is where vision evolved), so it’s kind of the only game in town.

By the time life moved onto land, vision was highly specialized. Ultraviolet and infrared can be used on lands since they pass through the air, but it’s tough to get there via natural selection. Marginally functional UV and IR sensing eye cells would dilute the already working other ones and likely make the organism less fit since it’s vision would overall be worse. It’s kind of like trying to evolve another joint in your limb. No matter how good it might be in 10 million years, it’s almost certainly bad NOW and will be selected against.

All that’s before getting into the problems of damaging other vision receptors if the eye lets in UV and noise issues since the animal’s body is a source of IR. Not that some animals haven’t come to use it. Some insects can see UV, and some can sense IR but don’t use their eyes for it.

Anonymous 0 Comments

the only thing special about the visible light spectrum is that we can see it.

the rest of the spectrum is just light we didn’t evolve or were built to see. as it was either not valuable to our way of life or very difficult to adapt to(probably both most of the time) as bees for example can see uv light but can’t detect colors they evolved a narrower and less complex view of light but with a different range or spectrum. different materials(chemicals) react to light and affect light differently. plants and animals developed pigmentation and color detection within fairly easy spectrum to use(due to availability of elements) to communicate(ie hey human i have a delicious apple ready for you to ingest, fertilize my seeds and poop it out somewhere it can grow.

the same is true of hearing frequencies.

Anonymous 0 Comments

There is not anything special about it. As we evolved those with eyes that were sensitive to that part of the spectrum were provided the best chance at survival. Therefore allowing those genes to be passed on to subsequent generations.

Anonymous 0 Comments

Simplest answer that doesn’t seem to have be explicitly said yet… you have a physical body, it’s only going to be possible to detect waves that interact with physical matter. Further long wave than infrared and the light becomes harder to focus with any lens the eye might have, rather is increasingly absorbed at heat. Further short wave than ultra violet and you get into low energy X ray territory, which will pass through most matter.

So since life is made of matter, any ‘eye’ you might have would have to make use of electromagnetic waves that most strongly interact with matter. Which is pretty much the visible spectrum range. (A little further either side is possible but natural selection has not found it to add much to survival)