Aquarius Resurfaced: Microbial diversity in massive starlet coral


During NEEMO XX, a fourteen-day mission aboard Aquarius, the aquanaut team assisted researchers from FIU’s IMaGeS Lab in the collection of samples used for a study on the microbial diversity within the massive starlet coral. This coral is considered to be one of the most resilient and adaptive corals on Caribbean reefs with high recovery rates from bleaching events, so FIU researchers were naturally interested in their associated microbes.

Reef-building corals, like the massive starlet stony coral, have diverse microbial communities within them that are vital to their metabolism and physiology. These microbial communities help corals fight disease, become resilient to environmental change and help them with nutrient cycling. Most of what scientists know about the microbial diversity within these corals is centered around bacteria and a type of microalgae that lives within the coral animal belonging to the genus SymbiodiniaceaeIn order to form a more complete picture of the microbial diversity within these corals it is important to study the Symbiodiniaceaethe bacterial and the fungal communities within the coral. This study was the first to characterize these three communities simultaneously.

Using DNA sequencing, the research team was able to characterize the microbial diversity of the massive starlet coral in depths of both 50 and 80 feet. This study demonstrated that while the bacterial and fungal communities remained consistent in both depths, there was a large diversity of the Symbiodiniaceae community within the massive starlet coral that varied depending on the depth. The deeper corals had Symbiodiniaceae communities that were genetically unique from the corals in shallower depths. This difference suggests that the massive starlet coral is able to adapt to various environments by switching which Symbiodiniaceae it hosts. This study has important implications for understanding the way this coral adapts to environmental stress.

Learn more about this project here.

Aquanaut team:

  • NASA aquanaut, David Coan
  • ESA astronaut, Luca Parmitano
  • NASA astronaut, Serena Auñon
  • JAXA astronaut, Norishige Kanai
  • Habitat technician, Mark Hulsbeck
  • Habitat technician, Sean Moore