Corals Engage in Fisticuffs with Global Warming


One of the richest hotbeds of diversity on the planet, coral reefs are also among the most vulnerable to climate change. Spikes of as little as 1 degree Celsius in sea-surface temperatures can kill off the symbiotic algae responsible for the color and nutrition of coral, resulting in a white or "bleached" appearance. And while coral can recover from bleaching if temperature aberrations resolve themselves in less than a month, the stress from sustained high temperatures can cause irreversible physiological damage, along with infections by pathogens that take advantage of the corals' compromised immunity.

But although warm temperatures occurring worldwide as a result of global warming is driving fatal epidemics in coral reefs across the globe, some corals, like the Caribbean gorgonian sea fan, aren't taking this lying down (so to speak).Drew Harvell, a professor of ecology and evolutionary biology at Cornell University, has noticed their surprising tenacity for warm temperatures. Not only are these corals somewhat temperature resilient, but they can also step-up their cellular and enzymatic defenses to fend off lethal microorganisms as temperatures get hotter. These abilities could someday be harnessed to help protect other fragile coral reefs, says Harvell.

"Some corals show unusual resilience to the double threat [of pathogens and warming seas], and we should look to these hardy corals for clues that might enhance others," said Harvell. "Other corals are more sensitive and will not survive the continued warming trend."

Another win for the home team: Scientists in Tel Aviv, Israel have isolated viruses that can attack several types of bacteria that are the bane of the more sensitive corals. :: Newswise
Image credit: Getty Images

Related Content on