Cool-water corals can adapt to a slightly warmer ocean, but only if global greenhouse gas emissions are reduced. That's according to a study published November 1 in the journal Science Advances of genetic adaptation and the likely effects of future warming on tabletop corals in the Cook Islands.
The study found that some corals in the normally cool waters of the Cook Islands carry genetic variants that predispose them to heat tolerance. This could help the population adapt more quickly to rising temperatures. But the preliminary results show they may not adapt quickly enough to outpace climate change.
"These corals aren't going to adapt at an unlimited rate," said lead author Rachael Bay, a postdoctoral scholar at the University of California, Davis. "Keeping these reefs around requires curbing emissions."
Simulating future climate
In previous work, the researchers identified genes that make some individual corals more heat tolerant than others. In the current study, they found these warm water variants in corals in the Cook Islands, at low levels.
To test how well the corals could use these genes to adapt to future climate change, the scientists ran computer simulations based on projections by the U.N. Intergovernmental Panel for Climate Change. In a business-as-usual scenario, emissions continue to rise rapidly throughout the 21st century, and temperatures rise between 2 and 3.7 degrees Celsius. The least severe scenario is where warming does not exceed 1.8 degrees Celsius by 2100. In between is the moderate scenario suggested by the Paris Accord, in which emissions peak and then rapidly decline by about 2040.
In the simulations, coral could survive under the mild and moderate scenarios. But under the more severe scenarios, adaptation was not fast enough to prevent extinction.
This research focused specifically on tabletop corals. Further study is needed to understand the broader implications for other coral species.
"Many existing coral populations have a bank of adaptations that has been evolving for a long time," said co-author Steve Palumbi from Stanford University. "Those existing adaptations are an asset for them to survive longer and for us humans to benefit longer."
Reef-building corals are among the most vulnerable organisms to rising ocean temperatures. Over the past three years, coral reefs have experienced the worst bleaching and mortality events in recorded history, largely due to warmer waters.
"This sort of framework could be used for any population we want to help adapt to future climate change, whether it's corals or birds or insects," Bay said. "It's a way to integrate the genomic data to produce tangible, predictive outcomes."
Explore further:
Coral reef experts deliver urgent recommendations for future research
More information:
R.A. Bay el al., "Genomic models predict successful coral adaptation if future ocean warming rates are reduced," Science Advances (2017). advances.sciencemag.org/content/3/11/e1701413
Shootist
2 / 5 (4) Nov 01, 2017How often has the climate changed in the past 1/2 billion years?
stankerns
2.3 / 5 (3) Nov 01, 2017Stan
thomasct
1 / 5 (3) Nov 02, 2017antialias_physorg
5 / 5 (3) Nov 02, 2017The question is: how fast has it changed? And is the speed of the current change slow enough for them to have a chance to adapt?
A fats change means a high selection pressure. If at any time all of the current organisms of a species are selected against it's game over. Evolution is not a magical silver bullet.
Any time we see fast change in the geological record we see mass extinctions (and let's not kid ourselves: Extinctions affect first and foremost higher lifeforms, as they are more reliant on multiple factors in the environment being just right)
barakn
not rated yet Nov 02, 201710% water vapor could occur in an minimum air temperature of ~47°C or 117°F, at 100% saturation. Unfortunately these kinds of temperatures occur in deserts where the air is typically nowhere near saturation. The record highest dewpoint was 95°F in Dhahran, Saudi Arabia, and the air temp was only 108°F. Do you have any proof of your 10% claim?
barakn
5 / 5 (2) Nov 02, 2017"The Mount Pinatubo eruption emitted 42 million tonnes of CO2 (Gerlach et al 1996). Compare this to human emissions in 1991: 23 billion tonnes of CO2 (CDIAC). The strongest eruption over the last half-century amounted to 0.2% of human CO2 emissions in that year." https://www.skept...php?r=50 Thomasct's purpose here is to misinform.
antialias_physorg
5 / 5 (3) Nov 02, 2017That shifts the balance a tiiiny bit. It also might make you understand why we're mounting up CO2 (and why this is a problem) whereas we're not mounting up water vapor (i.e. why man made water vapor is not a problem).
But hey, both have the same solution: Less fossil fuels (which produces CO2 AND water vapor upon use) and more wind, hydro and solar (which don't).
leetennant
not rated yet Nov 02, 2017If you'd done something radical like, I don't know, read the article you're commenting on, then you'd know they're talking about the pace of change and its impact on adaptation.
But that would involve educating yourself on the issue on which you have strong opinions. Wouldn't want to do that.
leetennant
5 / 5 (1) Nov 02, 2017In that increasing temperatures causes the climate to change then, yes, this is literally true.
Water vapour is between 1-4% of the atmosphere depending on location and even time of day. You know why varies so much? Because it's short-lived. CO2 is a weaker GHG but lasts longer.
As per the USGS, volcanos emit approximately 1% of human missions.
And with the methodology they use, there'd be no consensus on plate tectonics in geology. Unless you think every paper out of CERN must first establish a position on gravity.
These are all really easy facts to check with some basic effort.