January 28, 2014
Researchers Plea For Long-Term Ocean Acidification Research
Brett Smith for redOrbit.com - Your Universe Online
More research is necessary for an accurate determination of how marine species will cope long-term with ocean acidification, according to a new research review in the journal Trends in Ecology and Evolution.
"We can't measure evolutionary responses in all organisms, so we need to choose carefully to get the most bang for our buck," said review author Jennifer Sunday, a post-doctoral researcher at The University of British Columbia in Canada. "Species of ecological and economic importance, or species that will allow us to make useful generalizations, should be studied so we can project changes in our ocean ecosystems."
Study author Jonathon Stillman said the review provides “a way to move forward from people studying how organisms react to changes in the environment to being able to understand how they may evolve as the ocean changes.”
As the Earth's atmosphere gets ever more infused with carbon dioxide from the burning of fossil fuels, some of these greenhouse gases reacts with seawater, causing it to become more acidic. Notable scientific studies within the past two years, including one connecting the breakdown of Pacific Northwest oyster hatcheries to acidic waters, have made acidification into a commercial and political issue, in addition to being a scientific one.
According to the new review, if marine organisms adapt over time to acidification, they may react to acidic waters in a much different fashion than they do in the current oceans.
"We really don't need more studies that tell us how an organism is going to respond instantaneously," said Stillman, an associate professor of biology at San Francisco State University. "We need to know how they will really respond in the future and that depends on their capacity for adaptation."
Study researchers reviewed 18 studies on ocean acidification published between 2004 and 2013. The team’s analyses included methods that could increase the evolutionary focus of future research and possibly provide a clearer picture of the condition of our future oceans.
While most analyses of ocean acidification’s impact do not consider the potential for evolutionary responses, authors of the review were looking to highlight the small but growing list of reports that do and point to two experimental approaches: either raising organisms for multiple generations to model evolution in the laboratory or tracking genetic variation in normal populations.
“Both approaches have demonstrated some capacity for evolution, and now we must focus on the details of that process,” Sunday said. “Research must turn to actually estimating rates of evolutionary change in different species.”
The ideal study would be to track "organisms over many generations, and to be able to look at what the genetic contribution is to how they respond to changes in their environment," Stillman said. "It would be similar to breeding studies that the biomedical community has been doing for a long time in animals like mice, but it's something that we don't typically do that often or that well with marine organisms."
The review authors emphasized that future research should target ecologically important species, identify models that stand for taxonomic or functional groups, and consider uniqueness within the food web. They also said researchers should consider previous work on responses to additional stressors, such as rising water temperatures.