The world’s coral reefs are increasingly threatened by the changing climate. Both warmer ocean temperatures and increasing ocean acidification are damaging coral populations and endangering the very existence of coral reefs.
We think of corals as colorful fanciful structures under the sea, some of which are as big as automobiles. However, corals are actually tiny marine invertebrates. What we see are colonies composed of innumerable genetically identical polyps. Each polyp is a sac-like animal a few millimeters in diameter and a few centimeters in length. These polyps excrete a calcium-based exoskeleton that, when combined with those of its neighbors, forms the undersea structures we see.
Corals actually breed by spawning, an annual process of releasing eggs and sperm into the water under a full moon. A research group in Hawaii is trying to engage in selective breeding of corals in order to create strains that have the best chance of surviving increasingly inhospitable ocean conditions.
They tagged corals that were observed to survive a particularly hot spell in local waters and will pick specimens of these rugged individuals for use in “arranged coral marriages”. By this process of “assisted evolution”, they hope to create coral strains that can survive what is likely to be the warmer, more acid seas of the future.
This sort of process has been going in among the plants and animals in our own food supply for millennia. The notion that such selective breeding should be applied to coral reefs is a new one. But researchers looking at the decline of coral populations in places like the Great Barrier Reef and the Red Sea believe that this sort of proactive approach may be the last great hope for these amazing undersea colonies.
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As Ocean Waters Heat Up, A Quest to Create ‘Super Corals’
Photo, posted September 7, 2011, courtesy of Derek Keats via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio.