Background
The authors begin by stating that "metabolic rate determines the physiological and life-history performances of ectotherms [animals whose regulation of body temperature depends on external sources]," and, therefore, they add that "the extent to which such rates are sensitive and plastic to environmental perturbation is central to an organism's ability to function in a changing environment." Unfortunately, they also note that "little is known of long-term metabolic plasticity and potential for metabolic adaptation in marine ectotherms exposed to elevated pCO2."

What was done
"To define the potential for metabolic acclimatization and adaptation that allows colonization of elevated pCO2 areas," Calosi et al. "carried out a series of in situ transplant and mutual transplant experiments populated with polychaetes [a polyphyletic class of annelid worms] living around the shallow-water CO2 vents system off Ischia [Naples, Italy]." In the first of these experiments, they say they "characterized metabolic rates and responses of the polychaetes," which allowed them "to infer the potential for metabolic adaptation in tolerant versus sensitive species, as well as between populations of tolerant species found both inside and outside the vent areas."

What was learned
Noting that previous studies have shown that "unicellular organisms can adapt to elevated pCO2," citing Lohbeck et al. (2012), Benner et al. (2013) and Tatters et al. (2013), the eleven scientists say their study (1) "provides evidence that a marine ectotherm (Platynereis dumerilii) has been able to genetically and physiologically adapt to chronic and elevated levels of pCO2," and that it (2) "supports those studies that have indicated the potential of marine metazoans [animals with differentiated tissues, including nerves and muscles] to adapt to elevated pCO2," citing the work of Pespeni et al. (2013), Pistevos et al. (2011), Sunday et al. (2011), Foo et al. (2012), Schlegel et al. (2012), Padilla-Gamiño et al. (2013) and Kelly et al. (2013).

What it means
"Ultimately," in the words of Calosi et al., "the ability of marine organisms to persist in a rapidly changing ocean is largely dependent on the taxa's ability for rapid physiological adaption, which could potentially occur, via genetic assimilation of emerging phenotypes," as demonstrated by the studies of Ghalambor et al. (2007), Reznick and Ghalambor (2001), Waddington (1942), Torres Dowdall et al. (2012) and Pigliucci et al. (2006), while in reference to their own study, they say "it appears that both plasticity and adaptation may be key to prevent species' risk for extinction in the face of ongoing ocean acidification." And so it would also appear that the potential for polychaetes and many other marine life forms to successfully cope with ocean acidification is indeed rather good.

References
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