Publication Date:
2017-05-31
Description:
Ocean acidification severely affects bivalves, especially their larval stages. Consequently, the fate of this ecologically
and economically important group depends on the capacity and rate of evolutionary adaptation to altered ocean carbonate
chemistry.Wedocument successful settlement ofwild mussel larvae (Mytilus edulis) in a periodicallyCO2-enriched
habitat. The larval fitness of the population originating fromthe CO2-enriched habitat was compared to the response of a
population from a nonenriched habitat in a common garden experiment. The high CO2–adapted population showed
higher fitness under elevated PCO2 (partial pressure of CO2) than the non-adapted cohort, demonstrating, for the first
time, an evolutionary response of a natural mussel population to ocean acidification. To assess the rate of adaptation,
we performed a selection experiment over three generations. CO2 tolerance differed substantially between the families
within the F1 generation, and survival was drastically decreased in the highest, yet realistic, PCO2 treatment. Selection of
CO2-tolerant F1 animals resulted in higher calcification performance of F2 larvae during early shell formation but did not
improve overall survival. Our results thus reveal significant short-term selective responses of traits directly affected by
ocean acidification and long-term adaptation potential in a key bivalve species. Because immediate response to selection
did not directly translate into increased fitness,multigenerational studies need to take into consideration themultivariate
nature of selection acting in natural habitats. Combinations of short-termselectionwith long-term adaptation in populations
from CO2-enriched versus nonenriched natural habitats represent promising approaches for estimating adaptive
potential of organisms facing global change.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
Format:
application/pdf
Permalink