'Robust' corals primed to resist coral bleaching

November 1, 2018, ARC Centre of Excellence in Coral Reef Studies
New research has found "robust" corals, including this brain coral (Leptoria), may be more resilient, at least in the short term, to bleaching. Credit: ARC CoE for Coral Reef Studies/ Christopher Brunner

Using advanced genomic techniques, a team of researchers led by Dr. Hua (Emily) Ying of The Australian National University (ANU) and Prof David Miller of the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at James Cook University (JCU), have found that the group of corals classified as "robust," which includes a number of the brain corals and mushroom corals, have a key physiological advantage over "complex" corals, including common branching corals such as the staghorn coral.

In a new paper published today in the prestigious journal Genome Biology, researchers report that "robust" corals possess a unique capacity to generate an "essential" amino .

"Amino acids are the building blocks of life," said lead author Dr. Emily Ying of ANU Research School of Biology.

"Amino acids are crucial, for example, in repairing tissue or growing new tissue. But, generating is energetically costly for animals, so they usually only generate 11 of the 20 required for life. The remaining nine amino acids are called the 'essential' amino acids because they must be supplied by the animal's diet. For corals, this includes tiny drifting animals known as 'zooplankton.'"

But this is not the only form of sustenance for corals. Through a mutually-beneficial relationship with microalgae known as Symbiodinium, corals are supplied the energy needed to build their hard skeletons.

"Symbiodinium also supplies the with some of the 'essential' amino acids, making them less dependent on their diet than other animals," said senior author Prof David Miller of Coral CoE at JCU.

The research suggests that "robust" corals, such as brain corals, may be more resilient to bleaching than "complex" corals, such as branching staghorns, Orpheus Island QLD. Credit: ARC CoE for Coral Reef Studies/ Tory Chase

For example, when global warming causes corals to bleach, they expel their resident Symbiodinium and are therefore suddenly fully dependent on their diet to meet this nutritional requirement.

"We now know that 'robust' corals can make at least one of the 'essential' amino acids without relying on Symbiodinium. This suggests that they may be more resilient, at least in the short term, to bleaching than the 'complex' corals such as the branching staghorns," explained Prof Miller.

Until now, scientists had few clues about why some corals only host a specific Symbiodinium type and others are less particular.

"Our research also suggests that 'robust' corals are less choosey about which species of microalgae can take up residence in the coral's tissue. The ability to host a broader range of Symbiodinium types could facilitate more rapid acclimation to higher temperatures," said Prof Miller.

Explore further: A super-algae to save our seas

More information: Hua Ying et al, Comparative genomics reveals the distinct evolutionary trajectories of the robust and complex coral lineages, Genome Biology (2018). DOI: 10.1186/s13059-018-1552-8

Related Stories

A super-algae to save our seas

July 20, 2017

Coral reefs are our most diverse marine habitat. They provide over US$30 billion to the world economy every year and directly support over 500 million people. However, they are vulnerable with climate change impact models ...

Immunity could be key to addressing coral crisis

July 9, 2018

Coral reefs support a quarter of all marine life, feed hundreds of millions of people and contribute vastly to the global economy. But they are dying in mass bleaching events, as climate change warms our oceans and breaks ...

Helping corals to cope with pressure

August 28, 2017

Tiny plant cells, known as dinoflagellates, that live within coral tissue can help to regulate the osmotic pressure in corals to better cope with a highly saline environment. KAUST researchers suggest this may be one of the ...

Recommended for you

The friendly extortioner takes it all

February 15, 2019

Cooperating with other people makes many things easier. However, competition is also a characteristic aspect of our society. In their struggle for contracts and positions, people have to be more successful than their competitors ...

A river of stars in the solar neighborhood

February 15, 2019

Astronomy & Astrophysics publishes the work of researchers from the University of Vienna, who have found a river of stars, a stellar stream in astronomical parlance, covering most of the southern sky. The stream is relatively ...

Where is the universe hiding its missing mass?

February 15, 2019

Astronomers have spent decades looking for something that sounds like it would be hard to miss: about a third of the "normal" matter in the Universe. New results from NASA's Chandra X-ray Observatory may have helped them ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.