These aren’t the sponges you’d ordinarily meet with soapsuds in a bathtub. These eat meat.
Unlike other sponges, the newly discovered deep-sea sponge “Abestopluma” turns nature inside out. It has evolved a taste for animals that happen to swim into its spindly arms.
In contrast, ordinary sponges - including the bath kind - are filter-feeders, using small chambers to screen out tiny plants that flow through with seawater. So the discovery is a true surprise, reported Wednesday in the British journal Nature.
“All available evidence shows that the sponge is an effective carnivore,” wrote marine biologist Jean Vacelet, at the University of Aix, in Marseille, France.
Vacelet said the carnivorous sponges were found in a submerged Mediterranean cave, where normal sponge food - tiny marine plants - is scarce. Similar sponges, probably also carnivorous, tend to live about 30,000 feet deep in the open sea.
According to zoologist Michelle Kelly-Borges at the Natural History Museum in London, “sponges are impressively adaptable to their environment.” But it’s surprising one evolved so thoroughly it doesn’t much resemble a sponge anymore.