Multi‐generational responses of a marine polychaete to a rapid change in seawater pCO₂

Abstract

Little is known of the capacity that marine metazoans have to evolve under rapid p CO 2 changes. Consequently, we reared a marine polychaete, Ophryotrocha labronica, previously cultured for approximately 33 generations under a low/variable pH regime, under elevated and low p CO 2 for six generations. The strain used was found to be tolerant to elevated p CO 2 conditions. In generations F1 and F2 females’ fecundity was significantly lower in the low p CO 2 treatment. However, from generation F3 onwards there were no differences between p CO 2 treatments, indicating that trans‐generational effects enabled the restoration and maintenance of reproductive output. Whilst the initial fitness recovery was likely driven by trans‐generational plasticity (TGP), the results from reciprocal transplant assays, performed using F7 individuals, made it difficult to disentangle between whether TGP had persisted across multiple generations, or if evolutionary adaptation had occurred. Nonetheless, both are important mechanisms for persistence under climate change. Overall, our study highlights the importance of multi‐generational experiments in more accurately determining marine metazoans’ responses to changes in p CO 2, and strengthens the case for exploring their use in conservation, by creating specific p CO 2 tolerant strains of keystone ecosystem species.

Fluctuating thermal environments and time‐dependent effects on fruit fly egg‐hatching performance

“…Despite this, consequences to fitness may not only depend on the direct effects of extreme temperatures (Foray, Desouhant, & Gibert, ; Kostál, Renault, Mehrabianová, & Bastl, ), but environmental conditions experienced by parents could affect performance and fitness in their offspring (Salinas et al., 2013). Thus, transgenerational effects can mediate the negative impacts of extreme events (Donelson, Salinas, L. Munday, & Shama, ; Donelson, Wong, Booth, & Munday, ; Mousseau & Dingle, ; Rodríguez‐Romero, Jarrold, Massamba‐N'Siala, Spicer, & Calosi, ). As a consequence, future studies that incorporate the thermal history of organisms are important to predict the probable evolution and/or acclimation capacities of thermal sensitivity in nature.…”

Can trans‐generational experiments be used to enhance species resilience to ocean warming and acidification?

“…The experimental treatments were maintained using a carbon dioxide (CO 2 ) and temperature manipulation set‐up (Figure S1), similar to that described in Rodriguez‐Romero et al. (). Briefly, the system comprised of four deep trays (68 × 48 × 26 cm) that were half‐filled with deionized water.…”

“…Key, fitness‐related life‐history traits, including hatching event success, juvenile growth rate and survival to sexual maturity, fecundity, egg volume and female maximum size (Rodriguez‐Romero et al. ), were compared in offspring exposed within‐ and trans‐generationally. Physiological proxies for metabolic activity and function, and citrate synthase and electron transport system activities and reactive oxygen species (ROS) production (Moyes et al.…”

Historical baselines and the future of shell calcification for a foundation species in a changing ocean

“…Several exceptional long-term experiments show the existence of transgenerational effects on calcification [15], and the potential for adaptation [16] and evolutionary change [17,18]. However, such experiments are difficult for species with longer generation times or complex life cycles, and the responses of long-lived benthic marine species to ocean acidification (OA) remains poorly known [7].…”