Feeding is a sedentary act for reef sponges — as are all other tasks.
Sponges rely on water currents to carry nutritious phytoplankton and bacteria into their orbit since they’re attached to the seafloor.
Sometimes they ingest particles that are too big to break down, so they employ a familiar technique to dispose of waste.
Current Biology/Kornder et al
Writing this week in the journal Current Biology, researchers recorded sponges sneezing mucus in slow motion to rid their bodies of unwanted substances.
Georgette Douwma/Stone/Getty Images
“Let’s be clear: sponges don’t sneeze like humans do. A sponge sneeze takes about half an hour to complete. But both sponge and human sneezes exist as a waste disposal mechanism.”
Up close on the surface of the Caribbean stove-pipe sponge, Aplysina archeri, discarded particles form into stringy bits of mucus that accumulate at junctions all over its body.
Then over the course of roughly 30 minutes, the sponge constricts its tissue to free mucus clumps from its surface.
In this time-lapse, unidentified fauna swipe away bits of mucus from the surface of a sponge in the Great Barrier Reef.
And here, small worms scavenge inside the mucus highways of the sponge Hallsarca caerulea in the Southern Caribbean.
One organism’s trash is another’s treasure.
“Some organic matter exists in the water surrounding the coral reef, but most of it is not concentrated enough for other animals to eat. Sponges transform this material into eatable mucus.”