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Title: 10 - Adaptation and evolutionary responses to high CO2
The evolutionary history of fishes spans geological periods where atmospheric CO2 was much higher than the current-day, yet some extant species are now sensitive to high environmental CO2. Other species have adapted to live in habitats where they naturally encounter very high CO2 levels. This chapter explores the evolutionary history of fishes in relation to environmental CO2 and adaptations to high CO2 habitats. It then considers the potential for adaptive responses to predicted future CO2 levels from climate change among extant fishes. Despite a rich theory and well-developed experimental methods in quantitative genetics only a handful of studies have tested for genetic variation in CO2-sensitive traits, which might enable fish to adapt to projected future CO2 levels. This is a serious knowledge gap that needs a concerted research effort to overcome. Without basic information on genetic variation in fitness-associated traits and the strength of selection, it is not possible to make informed decisions about the impacts of elevated CO2 on fish populations over the timeframes that CO2 is changing.
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Grosell, Martin; Munday, Philip L.; Farrell, Anthony P.; Brauner, Colin J.
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Fish physiology
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National Science Foundation
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