10.5061/DRYAD.HHMGQNKCG
Caruso, Christina
0000-0001-7069-9572
University of Guelph
Panique, Hazel
University of Guelph
Simulated pollinator declines intensify selection on floral traits that
facilitate selfing and outcrossing in Impatiens capensis
Dryad
dataset
2020
Natural Sciences and Engineering Research Council
https://ror.org/01h531d29
2020-11-21T00:00:00Z
2020-11-21T00:00:00Z
en
38471 bytes
2
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
PREMISE OF THE STUDY: Anthropogenic environmental change is causing
pollinator populations to decline. These declines should intensify
selection for floral traits that facilitate outcrossing by making plants
more attractive to pollinators and/or for floral traits that facilitate
selfing in the absence of pollinators. However, the effect of pollinator
declines on selection on floral traits could be modified by other
environmental factors such as herbivores. METHODS: We studied the
effect of simulated pollinator declines on selection on floral traits of
Impatiens capensis, a mixed-mating species that produces both obligately
selfing cleistogamous flowers and primarily outcrossing chasmogamous
flowers. We measured directional selection differentials via seeds per
plant on two traits that facilitate outcrossing (chasmogamous flower size
and number) and one trait that facilitates selfing (cleistogamous flower
number) in ambient, reduced pollinator access, and reduced pollinator
access + increased foliar herbivory treatments. RESULTS: Reduced
pollinator access intensified selection for larger chasmogamous flowers
and more cleistogamous flowers. In contrast, increased herbivory did not
affect selection on any floral trait. CONCLUSIONS: Reduced pollinator
access intensified selection for a trait that facilitates outcrossing,
suggesting that even species such as I. capensis that can autonomously
self-pollinate have the potential to respond to pollinator declines by
evolving floral traits that reinforce interactions between plants and
pollinators. However, reduced pollinator access also intensified selection
for a trait that facilitates selfing, suggesting that I. capensis could
adapt to pollinator declines by evolving floral traits that maintain the
production of both selfed and outcrossed seeds.