by Staff Writers
Sydney (AFP) March 2, 2012
Coral offspring spawned from Australia's Great Barrier Reef clone themselves when rough weather hits with not all of the fragile embryos perishing in big waves, research showed Friday.
Scientists from the Australian Institute of Marine Science discovered the previously unknown reproductive strategy, which shows that coral offspring can form genetic clones of themselves before they settle and mature.
Coral "offspring" are usually the result of sexual reproduction -- fragile eggs fertilised either before or after being released into the water -- and are then carried by ocean currents before settling at new locations.
The new study, published in the prestigious journal Science, found that if there was some turbulence in the water such as a storm, these offspring often cloned to create genetic replicas of themselves rather than break up.
"We originally thought that if the embryos were fragmented by wave action that that the fragments may not develop into larvae," researcher Andrew Negri told AFP.
"However, when we investigated this we found that a high proportion of the fragments were successful in developing into smaller viable clones of the original embryo.
"Although smaller, these clones developed normally into coral larvae, eventually attaching and metamorphosing into coral polyps."
The researchers said they suspected the fact that fertilised coral eggs lacked a protective outer-layer or membrane, unlike most animal embryos, could be an evolutionary tactic to ensure reproduction.
"It appears that the lack of protective membrane is no accident," said Negri.
"Almost half of all these naked embryos fragmented in our experiments, suggesting that this has long been part of the corals' repertoire for maximising the impact of their reproductive efforts."
Fellow researcher Andrew Heyward said the coral, under threat from changing ocean temperatures, could benefit simultaneously from the advantages of both sexual and asexual reproduction.
"Much like humans, it is important that the offspring of corals have genetically distinct parents," he said.
"But these embryos also readily clone to form multiple versions of themselves, and it helps to explain how coral maximise their chances of finding a suitable habitat in which to settle and survive.
"In human terms this is the equivalent of giving birth to identical twins, triplets, quadruplets and so on."
Water News - Science, Technology and Politics
Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.
Forest refuse indirectly feeding bottom fish in the submarine canyons off Moloka'i
Honolulu, HI (SPX) Mar 01, 2012
Scientists from the School of Ocean and Earth Science and Technology (SOEST) at the University of Hawaii - Manoa (UHM) and colleagues recently discovered that land-based plant material and coastal macroalgae indirectly support the increased abundances of bottom fish in submarine canyons, like those off the north shore of Moloka'i. Less than a few miles from the shore, these underwater cany ... read more
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2012 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement|