Data from: Leaf herbivory imposes fitness costs mediated by hummingbird and insect pollinators

Plant responses induced by herbivore damage can provide fitness benefits,
but can also have important costs due to altered interactions with
mutualist pollinators. We examined the effects of plant responses to
herbivory in a hummingbird-pollinated distylous shrub, Palicourea
angustifolia. Through a series of field experiments we investigated
whether damage from foliar herbivores leads to a reduction in fruit set,
influences floral visitation, or alters floral traits that may influence
pollinator preference or pollinator efficiency. Foliar herbivory by a
generalist grasshopper led to reduced fruit set in branches that were
directly damaged as well as in adjacent undamaged branches on the same
plant. Furthermore, herbivory resulted in reduced floral visitation from
two common hummingbird species and two bee species. An investigation into
the potential mechanisms behind reduced floral visitation in induced
plants showed that foliar herbivore damage resulted in shorter styles and
lower nectar volumes. This reduction in style length could reduce pollen
deposition between different floral morphs that is required for optimal
pollination in a distylous plant. We did not detect any differences in the
volatile blends released by damaged and undamaged branches, suggesting
that foliar herbivore-induced changes in floral morphology and rewards,
and not volatile blends, are the primary mechanism mediating changes in
visitation. Our results provide novel mechanisms for how plant responses
induced by foliar herbivores can lead to ecological costs.