Chris Mah, National Museum of Natural History
This video shows the “real-life” doppelgangers of the popular Nickelodeon cartoon characters “SpongeBob SquarePants” and “Patrick Star.” The video was taken on July 27, 2021, at a depth of 1,885 meters (about 1.2 miles) during a remotely operated vehicle dive on Retriever Seamount, one of four seamounts within the Northeast Canyons and Seamounts Marine National Monument. “SpongeBob” is represented by the yellow glass sponge of the genus Hertwigia and “Patrick” by the pink poraniid sea star of the genus Chondraster.
Although many of us are familiar with the fictional characters these animals resemble, this imagery highlights the fact that our understanding of the diversity in the deep ocean is quite limited. Case in point, these two animals might actually represent new (i.e., undescribed) species!
Although we know relatively little about the biology of these species, one thing we have observed is that their relationship is most likely very different from the animated characters they resemble. This potentially new species of Chondraster has been observed feeding on sponges — the one seen here is most likely on its way to devour its yellow “companion”!
The yellow Hertwigia sponge is what’s known as a hexactinellid, or glass sponge, that is composed of biologically secreted silica, or glass. Its bright yellow color is unusual for deep-sea animals, which are often white or orange. Many sponges have strong chemical defenses which have made them very intriguing to pharmaceutical and other biochemical industries.
Although the Chondraster sea star is very poorly understood, many sea stars in the deep ocean are predators of sponges and corals. Sea stars can have significant effects on the communities they belong to, sometimes devouring and thus affecting the composition of the species that occur there.
Published August 3, 2021