Adaptation and acclimatization to ocean acidification in marine ectotherms: anin situtransplant experiment with polychaetes at a shallow CO₂vent system

Abstract

Metabolic rate determines the physiological and life-history performances of ectotherms. Thus, 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. Little is known of long-term metabolic plasticity and potential for metabolic adaptation in marine ectotherms exposed to elevated p CO 2 . Consequently, we carried out a series of in situ transplant experiments using a number of tolerant and sensitive polychaete species living around a natural CO 2 vent system. Here, we show that a marine metazoan (i.e. Platynereis dumerilii ) was able to adapt to chronic and elevated levels of p CO 2 . The vent population of P. dumerilii was physiologically and genetically different from nearby populations that experience low p CO 2 , as well as smaller in body size. By contrast, different populations of Amphiglena mediterranea showed marked physiological plasticity indicating that adaptation or acclimatization are both viable strategies for the successful colonization of elevated p CO 2 environments. In addition, sensitive species showed either a reduced or increased metabolism when exposed acutely to elevated p CO 2 . Our findings may help explain, from a metabolic perspective, the occurrence of past mass extinction, as well as shed light on alternative pathways of resilience in species facing ongoing ocean acidification.

Species-specific responses to ocean acidification should account for local adaptation and adaptive plasticity

“…Evaluating experimentally how marine organisms with multi-year generation times will respond to changes in physical-chemical conditions over long timescales can be extremely difficult. Comparative studies using species with geographic ranges spanning large environmental gradients in pH/p CO2 may help us to understand how long-term adaptation to different environments can modulate individual sensitivity to additional stressors 27,28 . However, there are few studies that have assessed how responses to changing pH/p CO2 conditions vary among individuals (that is, within the same species) from geographically distant populations [29][30][31] .…”

Long-term exposure to elevated pCO2 more than warming modifies early-life shell growth in a temperate gastropod

“…The energetic implications of dealing with multiple stressors can cause a reduction and/or reallocation of an organism's energy budget such that trade-offs among different homeostatic processes caused by a given stressor can reduce the individual's ability to cope with another stressor (e.g. Calosi et al, 2013). These interactions can lead to complex changes at the individual-level and in species interactions, affecting the natural structuring of biological communities (Queiros et al, 2015).…”

Calcareous green alga H alimeda tolerates ocean acidification conditions at tropical carbon dioxide seeps

“…Volcanic CO 2 seeps and areas of CO 2 upwelling have been described worldwide in temperate (Calosi et al 2013;Cigliano et al 2010;Hall-Spencer et al 2008;Inoue et al 2013;Johnson et al 2012;Porzio et al 2011) and tropical (Fabricius et al 2011(Fabricius et al , 2014Johnson et al 2012;Noonan et al 2013;Russell et al 2013;Uthicke and Fabricius 2012;Uthicke et al 2013) regions. So far, studies suggest reduced pH at CO 2 seeps in PNG lead to a decline in coral diversity with structurally complex species being particularly affected, and reduced taxonomic richness and density of coral juveniles, and low cover of crustose coralline algae (Fabricius et al 2011(Fabricius et al , 2014.…”