Study shows sea slugs act like plants

COLLEGE STATION, Texas, Nov. 26 (UPI) -- The sea slug is a bit of a chameleon, behaving more like a plant instead of the mollusk it is, Texas A&M University researchers found.

The Elysia chlorotica acts like a plant because it has at least one gene required for photosynthesis, the process by which plants trap the sun's energy and convert it to food, said Texas A&M biology Professor James Manhart.

"We found that the slug has at least one gene required for photosynthesis in its nuclear genome, which has never been found in any animal," Manhart said in a news release. "The critical thing is the plastids come from the alga but the slug nucleus contains at least one, and probably more, of the genes required for plastid functioning."

These plastids remain in the slug after it eats algae, photosynthesizing and providing it food, Manhart said. The result, he said, is the creature becoming a "solar-powered" slug and capable of making its own food like plants do.

"The slug needs the alga to mature and complete its life cycle," Manhart says. "It is totally dependent on the alga to survive. Once the slug has acquired a sufficient amount of plastids it can survive, like plants, for at least nine months by trapping solar energy and converting it into food."