Abstract Genetic variation is essential for adaptation to rapid environmental changes. Identifying genetic variation associated with climate-change related phenotypes is therefore the necessary first step towards predictive models of genomic vulnerability. Here we used a whole-genome scan to identify candidate genetic variants associated with differences in behavioural resilience to ocean acidification in a coral reef fish. We identified three genomic regions that differ between individuals that are behaviourally tolerant compared with behaviourally sensitive to elevated CO 2 . These include a dopamine receptor ( drd4rs ), cadherin related family member 5-like ( cdhr5l ), Synapse-associated protein 1 ( syap1 ), and GRB2 Associated Regulator of MAPK1 Subtype 2 ( garem2 ), which have previously been found to modify behaviour related to boldness, novelty seeking, and learning in other species, and differ between behaviourally tolerant and sensitive individuals. Consequently, the identified genes are promising candidates in the search of the genetic underpinnings and adaptive potential of behavioural resilience to ocean acidification in fishes.

Genetic architecture of behavioural resilience to ocean acidification