title: Masting promotes individual- and population-level reproduction by increasing pollination efficiency.
abstract: Masting is a reproductive strategy defined as the intermittent and synchronized production of large seed crops by a plant population. The pollination efficiency hypothesis proposes that masting increases pollination success in plants. Despite its general appeal, no previous studies have used long-term data together with population- and individual-level analyses to assess pollination efficiency between mast and non-mast events. Here we rigorously tested the pollination efficiency hypothesis in ponderosa pine (Pinus ponderosa), a long-lived monoecious, wind-pollinated species, using a data set on 217 trees monitored annually for 20 years. Relative investment in male and female function by individual trees did not vary between mast and non-mast years. At both the population and individual level, the rate of production of mature female cones relative to male strobili production was higher in mast than non-mast years, consistent with the predicted benefit of reproductive synchrony on reproductive success. In addition, at the individual level we found a higher conversion of unfertilized female conelets into mature female cones during a mast year compared to a non-mast year. Collectively, parallel results at the population and individual tree level provide robust evidence for the ecological, and potentially also evolutionary, benefits of masting through increased pollination efficiency.
authors.forename: Xoaquín
authors.initials: X
authors.lastname: Moreira
authors.forename: Luis
authors.initials: L
authors.lastname: Abdala-Roberts
authors.forename: Yan B
authors.initials: YB
authors.lastname: Linhart
authors.forename: Kailen A
authors.initials: KA
authors.lastname: Mooney
mesh_terms: D005298:Fertility; D041604:Pinus ponderosa / Q000502:physiology*; D054817:Pollination / Q000502:physiology*; D012639:Seeds / Q000502:physiology*; D013997:Time Factors