SCIENCE LAB SCATTER : SPONGES & SNEEZES

GESUNDHEIT !

How sponges fill the seas, sneeze by sneeze.

Sneezing is far from uniquely human behavior. Maybe you've seen your dog or cat do it, or watched a YouTube video of a giraffe sneezing on an unsuspecting toddler at the zoo. In fact, sneezing doesn't even require a nervous system, let alone a nose, and dates back to some of the first multicellular animals : sponges.

This sponge has been around for at least 600 million years. ''It's the most successful animal that I know of, because it's so old, and it's everywhere,'' said Jasper de Goeji, a marine ecologist at the University of Amsterdam.

As filter feeders, sponges play a crucial role in their aquatic systems, drawing in water filled with varied organic matter, processing it and releasing it as waste on which organisms like snails, brittle stars and tube worms feed.

''A sponge is basically an animal that has a lot of little mouths and one, or several, larger outflow openings,'' Dr. de Goeji said.

For years, scientists have known that sponges can regulate their water flow with a many-minutes-long body contraction - i.e., a ''sneeze'' - but now, Dr. de Goeiji and his colleagues have found that sponges appear to sneeze as a form of self-cleaning, releasing waste particles in mucus through their ostia.

The researchers came across sponges sneezing snot while working on a project investigating the role played by sponges in moving nutrients through a reef ecosystem.

Studying this mucus might improve scientists' understanding of how microbes, and possibly diseases, are transmitted in reef ecosystems, said Blake Ushijima, who studies corals at the University of North Carolina, Wilmington, and who was not involved in the new research. [Sam Jones]