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bioRxiv · 10.1101/2025.02.14.637444

Local adaptation of the mosquito vector, Aedes aegypti, and implications for predicting the effects of temperature and climate change on dengue transmission.

Abstract

There is concern that increases in temperature due to climate change could lead to shifts in the dynamics and distribution of mosquito vectors. Many current models assume there are average thermal performance curves for a given vector species transmission. However, this one-size-fits-all assumption ignores the potential for local adaptation to create population-specific differences in thermal performance. In this study, we explored thermal performance of five independent field populations of Ae. aegypti from Mexico, together with a standard laboratory strain. We reared these six populations at temperatures between 13{degrees}C-37{degrees}C to generate thermal performance curves for a suite of life-history traits. Composite models integrating these traits revealed the effects of temperature on population growth rates and dengue virus transmission potential. The results provide strong evidence for the potential for local adaptation in Ae. aegypti populations, challenging applicability of one-size-fits-all thermal performance models to assess climate impact on mosquito-borne diseases.

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Dennington, N., Grossman, M., Teeple, J., Johnson, L. R., Shocket, M., McGraw, E., Thomas, M. B.. 2025-02-17. Local adaptation of the mosquito vector, Aedes aegypti, and implications for predicting the effects of temperature and climate change on dengue transmission.. https://doi.org/10.1101/2025.02.14.637444

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