When it’s time to move, new studies reveal that a free-living coral disregards the traditional advice and heads directly toward the light.
When it’s migration time, research from QUT shows how a free-living coral bypasses conventional wisdom and gravitates straight to the light.
This study, spearheaded by Dr. Brett Lewis from the QUT School of Atmospheric and Earth Sciences along with the Reef Restoration and Adaptation Program, was published in PLOS One. It explored the movement, navigation, and light responsiveness of the free-living mushroom coral Cycloseris cyclolites in its natural settings.
“Not all coral species remain fixed to the ocean floor; some live independently and can roam to find their ideal environments,” noted Dr. Lewis.
“Nonetheless, the way these mobile corals journey and navigate during migration remains largely unclear.”
Cycloseris cyclolites is a charming little free-living mushroom coral known for its ability to move between various reef habitats, often in pursuit of the best light conditions.
Through high-resolution time-lapse photography, the research team discovered that Cycloseris cyclolites can traverse its environment using a method called pulsed inflation. This involves the coral inflating and deflating its tissue in rhythmic pulses to push itself forward, somewhat akin to the movement seen in jellyfish.
This method seems to be common among free-living corals, assisting in actions like reverting to an upright position if flipped, rejecting sediment when buried during storms, and now, moving towards light – all behaviors crucial for the coral’s survival in complex settings.
“Our research indicates that pulsed inflation is not merely a survival mechanism but a vital technique for migration and orientation,” Dr. Lewis explained.
“The capability of Cycloseris cyclolites to gravitate toward specific light sources is intriguing, drawing parallels to other marine organisms like jellyfish, suggesting they may possess more advanced neurological abilities than previously recognized.”
Additionally, it was found that Cycloseris cyclolites particularly favors blue light, with 86.7 percent of the corals moving toward blue light sources, as opposed to just 20 percent for white light.
This ability to differentiate between various light wavelengths fits with their preference for deeper water environments, where blue light is more prevalent, and may be essential for their migration to the optimal depths necessary for survival, reproduction, and dispersal.
The insights gathered concerning coral mobility reveal how closely related these corals are to jellyfish, which have been studied as pivotal to the evolutionary development of the centralized nervous system present in humans today.
“Our discoveries also carry significant ecological ramifications,” said Dr. Lewis.
“By understanding their migration tactics, researchers could better predict how these wandering corals might withstand, endure, or adjust to shifts in environmental factors, such as changes in sea temperatures due to climate change, which can be mitigated by the deeper waters these corals seek out.”
“As climate-driven changes escalate, a quicker migration could greatly improve their chances of survival.”
