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Why is blue-green bioluminescence common among ocean organisms?

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time-lapse photo of fireflies — Bioluminescence Time-lapse image of fireflies in the Catskill Mountains, New York. Firefly light is a cold light, with approximately 100 percent of the energy given off as light and only a minute amount as heat. Only light in the visible spectrum is emitted.

Blue-green bioluminescence is common among ocean organisms primarily because of the optical properties of seawater. In the electromagnetic spectrum, blue-green light corresponds to the wavelengths that experience the maximum transmission in seawater.12

While other wavelengths of light, such as ultraviolet and infrared, are absorbed rapidly by water, blue-green light is able to penetrate to greater depths. Because this light is the most available for scattering and transmission, it is the most visible to many deep-sea organisms. Consequently, the chemical reaction—in which the enzyme luciferase catalyzes the oxidation of the pigment luciferin—has evolved in many marine species to emit light at these specific wavelengths to ensure it can be effectively seen for purposes such as communication, attracting mates, or luring prey.3124