Sea creatures began to glow half a billion years ago

When a shaggy bamboo coral ( Isidella tentaculum ) gets jostled by the arm of a remotely operated submersible, its limbs begin to sparkle with bluish light. The gleam penetrates the blackness of the deep sea, where many octocorals—an ancient, diverse group of marine invertebrates that includes quill-shaped sea pens, bamboo corals, and other soft corals and waving sea fans—form lush underwater gardens. Some three-quarters of all undersea animals can generate their own light , but the origin of this ability has been shrouded in mystery. Now, research reported today in the Proceedings of the Royal Society B suggests the trait originated in octocorals at least 540 million years ago —nearly 300 million years earlier than scientists previously had thought. The findings demonstrate “how much we still have left to learn” about the creatures that illuminate Earth’s oceans, says Heather Bracken-Grissom, a marine evolutionary biologist at Florida International University who wasn’t involved in the work. Most bioluminescent animals use the same basic chemical reaction: an enzyme, luciferase, adds oxygen to a type of compound known as a luciferin, producing light as a byproduct. Previous research suggests this ability evolved at least 94 separate times , although some groups of animals that are predominantly bioluminescent contain a few “dull” members, which suggests the underlying chemica...
Source: Science of Aging Knowledge Environment - Category: Geriatrics Source Type: research