BIZARRE: Solar-powered worms are social sunbathers

What's weirder than a bright-green solar-powered worm? A bright-green solar-powered worm with a social life.

A serendipitous observation and a new series of computer simulations reveal that the mint-sauce worm is a social animal. The worm is a strange creature. Just a couple of millimeters long, these marine flatworms assemble in biofilms (a large group of microorganisms adhered to a surface)on seashores. They get their bright green color (and name) from the algae that live in their bodies. It's a codependent relationship: The algae get a home, and the worms get all of their nutrients from byproducts of algal photosynthesis.

Now, scientists have found that when the worms (Symsagittifera roscoffensis) are put in groups, they swim in circular patterns, nose to tail with one another. Researchers, observing this behavior for the first time, have also found that it occurs far more often than random chance would allow. The reason may be that the social behavior allows worms to form large groups, which, in turn, lets them regulate the amount of sun to which they expose their symbiotic algae. [

"These worms, by being social and aggregating, can create local conditions that better suit themselves," said study leader Nigel Franks, a biologist at the University of Bristol in the United Kingdom.

Report a Typo