Sign up for our free Health Check email to receive exclusive analysis on the week in health
Get our free Health Check email
Get our free Health Check email
A new study has found that the free-living mushroom coral responds to specific types of light by “walking” towards it, suggesting remarkable adaptability in the marine species.
Not all corals are attached to their seabed substrate, and some “free-living” species are known to migrate into preferred habitats.
But exactly how they move and navigate has remained a mystery.
The new study, published in the journal PLOS One, found that the small free-living mushroom coral Cycloseris cyclolites uses the movements of rolling, sliding or pulsing in pursuit of optimal light conditions.
Light exposure plays a key role in the survival of corals, influencing photosynthesis and their growth and health.
Researchers at the Queensland University of Technology in Australia used high-resolution time-lapse imaging to track mushroom corals as they were exposed to specific light wavelengths.
They found the coral moves by inflating and deflating its tissue in rhythmic bursts to propel itself forward, like jellyfish do, with a strong preference for blue and white light.
Such free-living corals seem to be using this previously unseen movement for other functions as well, such as self-righting when turned upside down and for sediment rejection when buried during storms, helping them survive in complex environments. “The ability of Cycloseris cyclolites to move towards specific light sources is a fascinating parallel to other marine species like jellyfish, which suggests they are more neurologically sophisticated than previously thought,” Brett Lewis, an author of the study, said.
The coral’s preference for specific light types appears to align with their preference for deeper water habitats, researchers said.
Blue light dominates at depths closer to the seafloor and showing preference for this wavelength could be crucial for the coral’s migration for survival, reproduction and dispersal.
The findings offer a window into the remarkable capabilities of corals, challenging perceptions of the organisms as passive entities.
Researchers said the study has implications for protecting corals threatened by climate change. “Understanding their movement strategies could help scientists predict how migratory corals might resist, survive or adapt to changes in environmental conditions such as sea surface changes caused by climate change, which can be reduced by the deeper waters these corals migrate to,” Dr Lewis said.
“With these climate-driven factors increasing, the faster the migration, the higher the chance of survival.”
