Australian scientists have discovered that some tropical fish have a greater capacity to cope with rising sea temperatures than previously thought ? by adjusting over several generations.
The discovery, by researchers at the ARC Centre of Excellence for Coral Reef Studies, James Cook University and CSIRO sheds a ray of hope amid the rising concern over the future of coral reefs and their fish under the levels of global warming expected to occur by the end of the 21st century.
Understanding the ability of species to acclimatise to rising temperatures over longer time periods is critical for predicting the biological consequences of global warming - yet it remains one of the least understood aspects of climate science. The scientists were seeking to discover how fish would cope with the elevated sea temperatures expected by 2050 and 2100.
"When we exposed damsel fish to water temperatures 1.5 degrees and 3 degrees above today's, there was a marked decline in their aerobic capacity as we'd expected," explains lead researcher Jennifer Donelson. "This affects their ability to swim fast and avoid predators."
"However when we bred the fish for several generations at higher temperatures, we found that the second generation offspring had almost completely adjusted to the higher temperatures. We were amazed? stunned, even," she says. "It shows that some species can adjust faster than the rate of climate change."
"When one generation of damselfish experiences high temperatures their whole life, the next generation is better able to cope with warmer water. We don't yet fully understand the mechanisms involved, but it doesn't seem to be simple Darwinian selection over a couple of generations," explains team leader Professor Philip Munday.
"Instead, there has been a transmission of information between the generations that enables damselfish to adjust to higher water temperatures."
The two temperatures used in the trial represent likely tropical ocean temperatures at the mid-century and by 2100, based on current trends in carbon dioxide emissions by humanity. A 3 degree increase in tropical ocean temperatures is the temperature predicted to occur if humanity's carbon dioxide emissions continue on their current trajectory.
The unusual finding suggests that some fish may have an innate ability to cope with increased sea temperatures greater than previously thought, the researchers say.
However they caution it applies so far only to a single coral reef fish species, and does not address the more complex issue of the survival of the coral habitat itself, and the effects of warming on plankton in the food chains on which fish depend.
Also, there are likely to be penalties for fish that successfully adapt to higher temperatures, Jennifer Donelson says. Initial observations suggest that the acclimatized offspring are on average smaller than their parents, and we still do not know if they are able to reproduce at the same rate as their predecessors.
Although the experiment has yet to run its full course, the researchers also say they do not expect the fishes' ability to adjust to higher temperatures to continue past 3 degrees.
"At such a level of planetary warming there will be profound changes in Earth's ecosystems, affecting all forms of life, including humans," says Prof. Munday.
However, assuming humans manage to gradually bring global warming under control, it is important to understand how well animals and plants can cope with higher temperatures, in order to manage ecosystems for optimum survival of their species and the services they provide. This research provides an early insight into the adaptive capacity of fish, the team says.
This study reveals that transgenerational acclimation is a potentially important mechanism for coping with rapid climate change. Such acclimation could reduce the impact of warming temperatures and allow some fish populations to persist across their current range, instead of having to move away in search of cooler waters.
###
"Rapid transgenerational acclimation of a tropical reef fish to climate change" by J. M. Donelson, P. L. Munday, M. I. McCormick and C. R. Pitcher, appears in the latest issue of the journal Nature Climate Change.
ARC Centre of Excellence in Coral Reef Studies: http://www.coralcoe.org.au/
Thanks to ARC Centre of Excellence in Coral Reef Studies for this article.
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
This press release has been viewed 10 time(s).
Source: http://www.labspaces.net/115716/When_the_heat_s_on__fish_can_cope
winston churchill winston churchill arkham city conjugated linoleic acid world series schedule apple earnings tampa weather
AndrolibJustIn 
The ongoing saga of Apple and Samsung slugging away at each other in patent courts all over the world continues, but in the U.S., the iPad maker has been stalled slightly in its attempts to get Samsung products banned from store shelves.
Best Buy has a deal to buy the Playstation 3D Display for $499.99, get a 160GB Playstation 3 for $100 and get an extra set of Sony 3D glasses for $25 when purchased with the Playstation Display. The PS3 Media/Bluray Remote is $14.99, SOCOM 4 is $19.99, Brink is $9.99.
Kmart provides Shop Your Way Rewards members with $50 in gaming coupons they purchase a 160GB PS3 and Battlefield 3 for PS3 and a $15 gaming coupon $40+ in gaming software is purchased.
Target offers a buy 1, get 1 50% off sale on select 3DS or DS games (Super Mario Land 3D, Starfox 64 3D, Pokemon Rumble Blast, Pokemon White, Power Rangers Samurai, Super Scribblenauts, Lalaloopay, Dora's Pet Shelter).
Toys R Us knocks 50% off any Xbox 360 or PS3 game when purchased with Need for Speed: The Run , Modern Warfare 2, Battlefield 3 or Assassin's Creed: Revelations. Buy the Skylanders Starter Pack (360/PS3), get a free Skylanders Adventure Pack. Buy Skylanders Starter Kit or Super Mario 3D Land on 3DS, get 50% off on any 3DS game. Buy Skylanders Starter Pack or Mario & Sonic at London Olympic Games, get 50% off on any Wii game. Select DS games are 2 for $40, including: Super Scribblenauts, Cars 2, Modern Warfare 3 and more.
Killzone 3: Helghast Edition $24.50 at Best Buy
Mass Effect 2 Digital Deluxe $11.99 and other download deals at Amazon
19 Days of Deals at Amazon
