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Title: Parental exposure of Eastern oysters ( Crassostrea virginica ) to elevated pCO2 mitigates its negative effects on early larval shell growth and morphology

Larvae of marine calcifying organisms are particularly vulnerable to the adverse effects of elevatedpCO2on shell formation because of their rapid calcification rates, reduced capacity to isolate calcifying fluid from seawater, and use of more soluble polymorphs of calcium carbonate. However, parental exposure to elevatedpCO2could benefit larval shell formation through transgenerational plastic responses. We examined the capacity of intergenerational exposure to mitigate the adverse effects of elevatedpCO2on Eastern oyster (Crassostrea virginica) early larval shell growth, shell morphology, and survival. Adult oysters were exposed to control (572 ppmpCO2) or elevatedpCO2(2827 ppmpCO2) conditions for 30 d during reproductive conditioning. Offspring from each parental treatment were produced using a partial North Carolina II cross design and grown under control and elevatedpCO2conditions for 3 d. We found evidence of transgenerational plasticity in early larval shell growth and morphology, but not in survival, in response to the parentalpCO2exposure. Larvae from parents exposed to elevatedpCO2exhibited faster shell growth rates than larvae from control parents, with this effect being significantly larger when larvae were grown under elevatedpCO2compared to control conditions. Parental exposure to elevatedpCO2, however, was insufficient to completely counteract the adverse effects of the prescribed elevatedpCO2on early larval shell formation and survival. Nevertheless, these results suggest that oysters have some capacity to acclimate intergenerationally to ocean acidification.

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Author(s) / Creator(s):
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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Limnology and Oceanography
Page Range / eLocation ID:
p. 1732-1745
Medium: X
Sponsoring Org:
National Science Foundation
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