Nav: Home

Corals light the way to a healthy partnership

January 21, 2019

Corals know how to attract good company. New research finds that corals emit an enticing fluorescent green light that attracts the mobile microalgae, known as Symbiodinium, that are critical to the establishment of a healthy partnership.

The study led by researchers at Japan's National Institute for Basic Biology and the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE) sheds new light on the mechanism that brings corals and Symbiodinium together, for example, following a bleaching episode.

"Most reef corals can not function without Symbiodinium," said Shunichi Takahashi from the National Institute of Basic Biology.

"Following the back-to-back mass bleaching events, images of bleached white coral contrasted with healthy, vibrantly coloured coral were widespread. The key difference between the two is the abundance of Symbiodinum in the coral's tissue. Without sufficient Symbiodinum, which provide corals with nutrients via photosynthesis, the coral will starve."

"Thirty percent of corals receive their Symbiodinium from their parents, the other seventy percent, need a different mechanism," said co-author Prof Andrew Baird of Coral CoE

But what brings the two organisms together? Corals are stationary creatures, however Symbiodinium can move freely through the water column.

The study reveals that corals have evolved a cunning ability to draw the Symbiodinium to them.

The researchers used the chalice coral, Echinophyllia aspera, to test whether the green fluorescent light emitted by corals under certain conditions can signal the Symbiodinium in the water column to move towards them: a process known as "positive phototaxis."

"Our research identifies a novel biological signaling tool that underlies the success of a relationship essential for healthy coral reef ecosystems, " said Prof Baird.
-end-
The paper "Green fluorescence from cnidarian hosts attracts symbiotic algae" is published in the journal Proceedings of the National Academy of Sciences.

ARC Centre of Excellence in Coral Reef Studies

Related Coral Articles:

Coral reefs: Centuries of human impact
In her AAAS talk, ASU researcher Katie Cramer outlines the evidence of the long-ago human footprints that set the stage for the recent coral reef die-offs we are witnessing today.
Coral genes go with the flow further than expected
Simulations reveal unexpected connections in the Red Sea basin that could help marine conservation.
New deep-water coral discovered
A new octocoral species was recently discovered in a biodiversity hotspot and World Heritage Site in Pacific Panama.
3-D printed coral could help endangered reefs
Threats to coral reefs are everywhere--rising water temperatures, ocean acidification, coral bleaching, fishing and other human activities.
How to restore a coral reef
New guidelines drafted by a consortium of concerned experts could enable corals to adapt to changing environments and help restore declining populations in the Caribbean.
Fussy fish can have their coral, and eat it too
Fussy fish seeking refuge from climate change on deeper reefs can still keep their specialised diets.
Coral reefs shifting away from equator
Coral reefs are retreating from equatorial waters and establishing new reefs in more temperate regions, according to new research in the journal Marine Ecology Progress Series.
Changing how we predict coral bleaching
A remote sensing algorithm offers better predictions of Red Sea coral bleaching and can be fine tuned for use in other tropical marine ecosystems.
Leopard coral grouper: Overexploited
Researchers measured the population stock in Saleh Bay, Indonesia of the commercially valuable leopard coral grouper (Plectropomus leopardus), a species subject to population collapse due to high fishing pressure.
Coral reefs can't return from acid trip
When put to the test, corals and coralline algae are not able to acclimatise to ocean acidification.
More Coral News and Coral Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Uncharted
There's so much we've yet to explore–from outer space to the deep ocean to our own brains. This hour, Manoush goes on a journey through those uncharted places, led by TED Science Curator David Biello.
Now Playing: Science for the People

#555 Coronavirus
It's everywhere, and it felt disingenuous for us here at Science for the People to avoid it, so here is our episode on Coronavirus. It's ok to give this one a skip if this isn't what you want to listen to right now. Check out the links below for other great podcasts mentioned in the intro. Host Rachelle Saunders gets us up to date on what the Coronavirus is, how it spreads, and what we know and don't know with Dr Jason Kindrachuk, Assistant Professor in the Department of Medical Microbiology and infectious diseases at the University of Manitoba. And...
Now Playing: Radiolab

Dispatch 1: Numbers
In a recent Radiolab group huddle, with coronavirus unraveling around us, the team found themselves grappling with all the numbers connected to COVID-19. Our new found 6 foot bubbles of personal space. Three percent mortality rate (or 1, or 2, or 4). 7,000 cases (now, much much more). So in the wake of that meeting, we reflect on the onslaught of numbers - what they reveal, and what they hide.  Support Radiolab today at Radiolab.org/donate.