As you can see from the illustration above, visible light is only a very small portion of all light waves. You may ask yourself why is it that we only see the "visible" portion of light? If you study the illustration above, you will see at the earth's surface almost all the wavelengths with any significant energy are visible (see the green peak). There are some very small amounts of ultraviolet and infrared wavelengths that are present. In some cases, insects and animals have adapted to see with those wavelengths.

* Actual scale is spectral irradiance [kw/(m²mm)]. Solar spectral irradiation on a horizontal surface at sea level: clear day with the sun at its highest point.