Thermal performance of Aedes sierrensis life history traits for populations collected across the species range

How mosquitoes may respond to rapid climate warming remains unknown for
most species, but will have major consequences for their future
distributions, with cascading impacts on human well-being, biodiversity,
and ecosystem function. We investigated the adaptive potential of a
wide-ranging mosquito species, Aedes sierrensis, across a large climatic
gradient by conducting a common garden experiment measuring the thermal
limits of mosquito life history traits. Although field-collected
populations originated from vastly different thermal environments that
spanned over 1,200 km, we found limited variation in upper thermal
tolerance between populations. In particular, the upper thermal limits of
all life history traits varied by <3°C across the species range
and, for most traits, did not differ significantly between populations.
For one life history trait—pupal development rate—we did detect
significant variation in upper thermal limits between populations, and
this variation was strongly correlated with source temperatures, providing
evidence of local thermal adaptation for pupal development.
 However, we found that maximum environmental temperatures across
most of the species’ range already regularly exceed the highest upper
thermal limits estimated under constant temperatures. This result suggests
that strategies for coping with and/or avoiding thermal extremes are
likely key components of current and future mosquito thermal tolerance.