From wikipedia - "The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye."
So humans can see the light from 400-700 nm and this is because our eyes can interpret/sense this little portion of the electromagnetic spectrum.
I wonder - could somewhere out there exist a creature which is possible to see different part of the spectrum ? I know that on Earth a creature can have a different visual spectrum "flavour" but I do not know whether it is possible the visible spectrum to be completely different - e.g. on some other planet can creatures exist that can say to see light in lets say 1500-2000 nm ?