Bioluminescence on Earth Evolved Over 500 Million Years Ago, Study Finds

In the darkest corners of the planet, where the light of the Sun never touches, eerie glows can yet be found, illuminating the shadows.

This is bioluminescence, a remarkable ability that has evolved, separately, at least 94 times throughout the history of life on Earth. Bioluminescent organisms can harness chemical reactions to produce a glow of their own, a tool used for various purposes by the different creatures that wield it.

Scientists have traced this tool to its earliest known evolutionary origins: a class of corals called Octocorallia in the depths of the ocean in the Cambrian, some 540 million years ago. This is more than double the age of the previous title holder, a tiny deep-ocean crustacean that lived 267 million years ago .

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