Research further explores coral-algae relationship
14 Nov 2016 by Evoluted New Media
An extensive study by researchers has revealed new insights on the relationship between Carribean coral and symbiotic algae.
An extensive study by researchers has revealed new insights on the relationship between Carribean coral and symbiotic algae.
Led by researchers at the University of Exeter, more than 630 coral samples from 33 sites across the Caribbean were analysed. Rising water temperatures caused by global warming are a threat to coral reefs as it causes coral bleaching, ending with the death of coral.
Dr Jamie Stevens, from the University of Exeter and a co-author of the study, said: “The relationship between coral and symbiotic algae is crucial to the survival of coral, and the more we can understand about how and why it occurs, the better our chances of protecting and reinstating the reefs that are fundamental to a healthy marine ecosystem. This is the first time anyone has had enough data to explore this in detail.”
The reef building coral (Orbicella annularis) - found across the Caribbean - and the singled celled algae, (Symbiodinium) were the focus of this study, carried out in collaboration with the University of Queensland. Symbiodinium colonises corals, providing nutrients through photosynthesis, which the coral cannot do itself.
It is this relationship scientists determined was affected by rising sea temperatures. In the Caribbean, 14% of reefs have suffered severe coral death with an additional 46% of reefs classified as threatened. As coral plays a vast role in marine ecosystems the knock on effects to marine wildlife could be devastating.
There are hundreds of different species of Symbiodinium and while many corals will often pair with one specific type, Orbicella annularis can team up with different types, and sometimes even mixes of different species. This can determine the ‘behaviour’ of the coral.
Dr Emma Kennedy, lead author, also from the University of Exeter, said: “Genetically identical corals containing different algae mixes may grow differently or respond differently to stress, depending on the hardiness of the algae, how efficiently it photosynthesises, or how many nutrients it supplies to the host. Who you’re paired up with might well be the difference between life and death for a coral experiencing a mass bleaching event.”
The research was funded by the Natural Environment Research Council, the EU and the UK. The study was published in Proceedings of the Royal Society B.
