Data from: Natural selection on floral morphology depends on climate

Climate has the potential to influence evolution, but how it influences
the strength or direction of natural selection is largely unknown. We
quantified the strength of selection on four floral traits of the
subalpine herb Ipomopsis sp. in 10 years that differed in precipitation,
causing extreme temporal variation in the date of snowmelt in the Colorado
Rocky Mountains. The chosen floral traits were under selection by
hummingbird and hawkmoth pollinators, with hawkmoth abundance highly
variable across years. Selection for flower length showed environmental
sensitivity, with stronger selection in years with later snowmelt, as
higher water resources can allow translation of pollination success into
fitness based on seed production. Selection on corolla width also varied
across years, favouring narrower corolla tubes in two unusual years with
hawkmoths, and wider corollas in another late snowmelt year. Our results
illustrate how changes in climate could alter natural selection even when
the primary selective agent is not directly influenced.