Featured Research

from universities, journals, and other organizations

Predicting Coral Health By Identifying Nearby Microscopic Algae

Date:
July 23, 2008
Source:
University of Hawaii at Manoa
Summary:
A new indicator of coral health has been discovered in a community of microscopic single-celled algae called dinoflagellates. The study reveals that a particular type of these algae renders corals more susceptible to disease.

A diseased coral.
Credit: Michael Stat, HIMB/SOEST

A new indicator of coral health has been discovered in a community of microscopic single-celled algae called dinoflagellates. The study reveals that a particular type of these algae renders corals more susceptible to disease.

Related Articles


"Corals are fascinating organisms whose survival is dependent on dinoflagellates that live inside the coral's tissue," says lead author Michael Stat, an assistant researcher at the Hawaii Institute for Marine Biology (HIMB) at the University of Hawaii at Manoa. "The relationship between these dinoflagellates and corals has long been considered mutually beneficial, with the dinoflagellates supplying the coral with food via photosynthesis in return for recycled nutrients and shelter. Over the last 20 years it has been made clear that there are many different types of dinoflagellates in corals and that the unions or symbiosis between a given coral and their dinoflagellates can be very specific."

It had previously been considered that all dinoflagellates found in coral are equally beneficial to their coral host, but in this study Stat, along with HIMB researchers Ruth Gates and Emily Morris, present evidence that a particular type of dinoflagellate can be found in corals that are diseased or show evidence of having had a disease.

"We show that this same symbiont, called "clade A", does not produce as much food that can be used by the coral as other types of coral dinoflagellates," says Stat. "We suggest that because these coral are not receiving enough food they become more prone to disease."

The researchers sampled corals that appeared healthy and corals that appeared diseased from French Frigate Shoals in the Papahanaumokuakea Marine National Monument in the Northwestern Hawaiian Islands (NWHI). By using genetic analyses, they were able to identify the type of dinoflagellate that was present in each of these corals. They found that the healthy coral contained one type of dinoflagellate and the diseased coral contained a different type of symbiont.

"We have discovered that a group of diseased corals in the NWHI associate with a type of endosymbiotic algae that has never been found in Hawaiian corals before," says co-author Ruth Gates, an Associate Researcher at HIMB. "Our analyses suggest that these endosymbiotic algae are not providing the coral with nutrition and that the corals may be starving, making them more susceptible to disease."

To mimic the inside of coral tissue, they performed lab-controlled experiments looking at the amount of carbon produced and released by different coral dinoflagellates in an artificial environment. They found that the dinoflagellate found in healthy coral produced large amounts of carbon that it released into the outside environment, making it available to a coral as a source of food. In contrast, the dinoflagellate found in diseased coral produced a very small amount of carbon and did not release any to the outside environment to make available to a coral host as a source of food.

"Just as we have tests for human diseases such as cancer and tuberculosis, we now have the ability to screen corals for disease susceptibility," says Gates. "This discovery is a key finding that will contribute to the conservation and protection of ecologically important corals in Hawaii and elsewhere."

"This work shows for the first time that different types of coral dinoflagellates are not equally beneficial, and that there is a link between the type of dinoflagellate and coral disease," says Stat. "We also suggest that some dinoflagellates living inside coral may be acting more as a parasite than a mutualistic symbiont. The next stage in our research is to further understand the range of interactions between coral and dinoflagellates and to determine whether some types are directly harming the coral and acting as parasites."

This research was funded by the National Marine Sanctuary Program, the Hawaii Institute of Marine Biology Reserve Partnership and the National Science Foundation.


Story Source:

The above story is based on materials provided by University of Hawaii at Manoa. Note: Materials may be edited for content and length.


Journal Reference:

  1. Stat et al. Functional diversity in coral-dinoflagellate symbiosis. Proceedings of the National Academy of Sciences, 2008; 105 (27): 9256 DOI: 10.1073/pnas.0801328105

Cite This Page:

University of Hawaii at Manoa. "Predicting Coral Health By Identifying Nearby Microscopic Algae." ScienceDaily. ScienceDaily, 23 July 2008. <www.sciencedaily.com/releases/2008/07/080718085114.htm>.
University of Hawaii at Manoa. (2008, July 23). Predicting Coral Health By Identifying Nearby Microscopic Algae. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2008/07/080718085114.htm
University of Hawaii at Manoa. "Predicting Coral Health By Identifying Nearby Microscopic Algae." ScienceDaily. www.sciencedaily.com/releases/2008/07/080718085114.htm (accessed October 25, 2014).

Share This



More Earth & Climate News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

EU Gets Climate Deal, UK PM Gets Knock

EU Gets Climate Deal, UK PM Gets Knock

Reuters - Business Video Online (Oct. 24, 2014) EU leaders achieve a show of unity by striking a compromise deal on carbon emissions. But David Cameron's bid to push back EU budget contributions gets a slap in the face as the European Commission demands an extra 2bn euros. David Pollard reports. Video provided by Reuters
Powered by NewsLook.com
Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Raw: Tornado Rips Roofs in Washington State

Raw: Tornado Rips Roofs in Washington State

AP (Oct. 24, 2014) A rare tornado ripped roofs off buildings, uprooted trees and shattered windows Thursday afternoon in the southwest Washington city of Longview, but there were no reports of injuries. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Fast-Moving Lava Headed For Town On Hawaii's Big Island

Fast-Moving Lava Headed For Town On Hawaii's Big Island

Newsy (Oct. 24, 2014) Lava from the Kilauea volcano on Hawaii's Big Island has accelerated as it travels toward a town called Pahoa. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins