Let me rephrase the question – Do we call the Visible Spectrum that because that’s what we can see or is there something different about that part of electromagnetic spectrum (ES) that allow vision to occur. Alternately, If light is dual in nature, being both a wave and a particle, is that the same for other parts of the ES?
Which brings me to the question that I’m most curious about; would it be possible for a creature exist that can see, the same way we see, but using frequencies from other areas of the ES?
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Yes, there are creatures that can see outside of the human visible spectrum, but not very far. Just a bit into the infrared and the ultraviolet.
As for why we can detect those wavelengths, two main reasons. One, those wavelengths pass through water. As it is believed that life started in the ocean, the first eyes would only have been able to detect light that could penetrate into the ocean.
Second, these wavelengths have the property that they can interact with small molecules. Infrared light and longer wavelengths are too big and weak to effect much, and mostly just scatter off our cells. Ultraviolet light and smaller wavelengths are too small and powerful, and will shoot right through our cells, mostly zipping right through but sometimes causing damage. The wavelengths in between, however, can be absorbed by the right kind of molecule, and the energy of that absorption can be used to send a signal that “hey, I just caught a photon!”
So yes, the visible range does have some special properties that make it suitable for use in vision.
I have heard anecdotal tales of insects being affected by very long wavelengths, like the 120 Hz signal from power lines, but I have not seen any scientific confirmation. It is possible that some creatures can detect wavelengths far from the visual spectrum in some way, but it wouldn’t be in the form of “vision.”
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