Prof Tim Ravasi and Dr Davide Spatafora present their research on how the molecular basis and behavioural adjustments reveal potential local adaptation to acidifying oceans, a lesson from natural analogues, the second webinar from the International CO2 Natural Analogues (ICONA) Network. The first response by animals to a changing environment is predominantly through modification of their behaviour. In this context, investigating behavioural responses of fish living under low-pH/high-CO2 conditions (e.g. off volcanic seep sites) may contribute to a better understanding of how marine species might adjust or adapt to environmental conditions under projected ocean change scenarios. We carried out field-based observations and translocation experiments in the Vulcano island natural CO2 seep (southern Italy) to assess whether there is evidence for local behavioural adaptation and/or acclimatization of fish after long and short-term exposure to ocean acidification conditions predicted to occur by the end of this century. The responses of two temperate fish species, characterized by a limited home range, have been investigated and compared between fish from low-pH/high pCO2 sites and fish from control sites. Furthermore, understanding the molecular underpinnings responsible for acclimatization to acidified waters, by means of an integrated study of the brain transcriptional program of wild fish species, can elucidate on the variation in responses. We collected 130 individuals of six different reef fish species from a natural volcanic CO2 seep and nearby control reefs in Papua New Guinea. Differences in brain gene expression in fish from CO2 seeps compared to fish from control sites as well as differences among species identified the molecular pathways controlling the cellular responses to elevated CO2. These studies provide a broader understanding as to the behavioural and molecular alterations crucial for coping with naturally elevated CO2 conditions.
GOA-ON, YouTube, 2 November 2022. Video.
