Deep-sea biologists surveying the Weddell Sea in Antarctica came across an icefish nesting site that is roughly the size of the island nation of Malta.
Absorbent and yellow and … mobile? Sea sponges on the move in Arctic Ocean
A new study suggests that sea sponges are moving across the seafloor of the Arctic Ocean, which challenges the idea that these creatures are primarily immobile.
Previous research has shown that sponges can make limited movements in a laboratory setting, but this is the first time sea sponge trails have been observed in the ocean and attributed to sponge movement.
The researchers hypothesize that the sponges are moving to find food or disperse juveniles, although further research is needed before conclusions can be drawn.
Sea sponges don’t move. At least, that’s what a lot of people used to think about these aquatic invertebrates. But a new study has upended this assumption, and pushed and prodded scientific thought into a new direction.
Arctic sponges leave trails as they wander
The sponges were thought to be stationary, but they leave sneaky spikes on the seafloor.
Trails left by sponges as they crawl across the seafloor. Credit: AWI OFOBS team, PS101
Adult marine sponges are usually thought to be stationary, picking a spot on the seafloor while still in their larval stage and sticking to it. Lacking muscles to move around, they’re referred to as ‘sessile’ – fixed in one place, as opposed to ‘motile’ marine creatures.
But a paper published in
Current Biology has described trails across the Arctic seafloor, made of brown spicules: spikes that belong to the sponges and provide structural support. This indicates that the mature sponges were on the move.