Biofluorescence is the absorption of electromagnetic wavelengths from the visible light spectrum by fluorescent proteins in a living organism, and the reemission of that light at a lower energy level. This causes the light that is absorbed to be a different color than the light that is re-emitted. Stimulating light excites an electron, raising energy to an unstable level. This instability is unfavorable, so the energized electron is returned to a stable state almost as immediately as it becomes unstable. This return to stability corresponds with the release of excess energy in the form of fluorescent light. This emission of light is only observable when the stimulant light is still providing light to the organism/object and is typically yellow, orange, red, green, or purple. Biofluorescence is often confused with the following forms of biotic light, bioluminescence and biophosphorescence