RT Journal Article
SR Electronic
T1 Interactions during growth eclipse interactions during flowering for determining plant fecundity in pollinator-sharing annual plants
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.03.31.437969
DO 10.1101/2021.03.31.437969
A1 Aubrie R. M. James
A1 Monica A. Geber
YR 2021
UL http://biorxiv.org/content/early/2021/04/01/2021.03.31.437969.abstract
AB Species interactions are foundational to ecological theory, but studies often reduce the complex nature of species interactions. In plant ecology, the result is that interactions during vegetative growth and flowering are considered separately, though both can affect fecundity. Here we use a system of annual flowering plants in the genus Clarkia to ask how interactions during flowering and growth contribute to plant interactions, and if pollinator behaviors explain apparent patterns in plant interactions during flowering. We measure seed success and fecundity of Clarkia focal plants in experimental interaction plots with the effect of pollinators experimentally removed or retained. We also observe pollinator behaviors in the plots and experimental arrays. During flowering, pollinators significantly changed the effect of Clarkia interactions on seed success in 31% of species interactions, and these changes corresponded to pollinator behaviors. Whole-plant fecundity, however, did not depend on interactions between Clarkia; instead, non-Clarkia forbs that grew earlier in the season limited fecundity, constituting a priority effect during vegetative growth. Our study shows that interactions during vegetative growth can preclude the effect of pollinator-mediated interactions on fecundity by limiting potential reproductive output, and that simultaneously studying different modes of interaction allows for understanding the contingency of ecological outcomes.Competing Interest StatementThe authors have declared no competing interest.