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bioRxiv · 10.1101/2020.10.29.361568

Elevated temperatures drive the evolution of armor loss in the threespine stickleback Gasterosteus aculeatus

Smith, C.·Zieba, G.·Przybylski, M.
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Abstract

While there is evidence of genetic and phenotypic responses to climate change, few studies have demonstrated change in functional traits with a known genetic basis. Here we present evidence for an evolutionary adaptive response to elevated temperatures in freshwater populations of the threespine stickleback (Gasterosteus aculeatus). Using a unique set of historical data and museum specimens, in combination with contemporary samples, we fitted a Bayesian spatial model to identify a population-level decline in the number of lateral bony plates, comprising anti-predator armor, in multiple populations of sticklebacks over the last 90 years in Poland. Armor loss was predicted by elevated temperatures and is proposed to be a correlated response to selection for reduced body size. This study demonstrates a change in a functional trait of known genetic basis in response to elevated temperature, and illustrates the utility of the threespine stickleback as a model for measuring the evolutionary and ecological impacts of environmental change across the northern hemisphere.

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Smith, C., Zieba, G., Przybylski, M.. 2020-10-30. Elevated temperatures drive the evolution of armor loss in the threespine stickleback Gasterosteus aculeatus. https://doi.org/10.1101/2020.10.29.361568

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