Marine losers abound in the hustling currents of warming and acidifying oceans. Trying to figure out which types of sea life, particularly those that form calcium carbonate-rich cells and exoskeletons, such as some plankton, corals, and shellfish, will thrive amid climate change can be like playing a high-stakes shell game.
New research suggests that at least one type of plankton could overcome what would seem to be long odds, and double down on its ecosystem dominance. The surprise finding is a positive early development in an oft-bleak field as scientists start to investigate which marine species face the greatest risks of dying out — their shells emptied by the lethal effects of environmental switcheroos.
Most of global warming’s heat is ending up in the oceans, making the waters less hospitable for many species.
And a quarter of the carbon dioxide pumped into the air by humans is dissolving into oceans, where it undergoes chemical reactions that increase the water’s acidity by reducing concentrations of carbonates that some organisms use to produce shells. These changes have contributed to coral bleaching, to holes in sea snail shells, and to die-offs at oyster farms.
Coccolithophores are single-celled plants surrounded by individual calcium carbonate sheaths that underpin many food webs. They form plankton blooms so thick they are tracked using satellites.
Researchers working in a laboratory exposed a species of the plankton, Emiliania huxleyi, to fast-paced environmental changes reminiscent of those underway in the wild. They reported Sunday in the journal Nature Climate Change that they had observed surprisingly fast rates of evolutionary adaptation.
Much more work with this and other types of sea life will be needed before scientists can paint any kind of clear picture of the future of marine ecosystems. But the findings provide important early clues.
“You will get species that are able to evolve, and others that are not,” Reusch said. “That’s a big question that will occupy us for the next 10 or 20 years; to find out if there are any meta attributes that we can tell from the genomes, and from the physiology, that are telling us how evolutionarily flexible they are.”
http://www.weather.com/news/science/environment/what-survive-oceans-hotter-acidic-20140915
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