title: Predation on rose galls: parasitoids and predators determine gall size through directional selection.
abstract: Both predators and parasitoids can have significant effects on species' life history traits, such as longevity or clutch size. In the case of gall inducers, sporadically there is evidence to suggest that both vertebrate predation and insect parasitoid attack may shape the optimal gall size. While the effects of parasitoids have been studied in detail, the influence of vertebrate predation is less well-investigated. To better understand this aspect of gall size evolution, we studied vertebrate predation on galls of Diplolepis rosae on rose (Rosa canina) shrubs. We measured predation frequency, predation incidence, and predation rate in a large-scale observational field study, as well as an experimental field study. Our combined results suggest that, similarly to parasitoids, vertebrate predation makes a considerable contribution to mortality of gall inducer larvae. On the other hand, its influence on gall size is in direct contrast to the effect of parasitoids, as frequency of vertebrate predation increases with gall size. This suggests that the balance between predation and parasitoid attack shapes the optimal size of D. rosae galls.
authors.affiliation: Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Cluj-Napoca, Romania.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: László
authors.affiliation: Ecological Department, University of Debrecen, Debrecen, Hungary.
authors.forename: Katalin
authors.initials: K
authors.lastname: Sólyom
authors.affiliation: Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Cluj-Napoca, Romania.
authors.forename: Hunor
authors.initials: H
authors.lastname: Prázsmári
authors.affiliation: MTA-DE "Lendület" Behavioural Ecology Research Group, Department of Evolutionary Zoology, University of Debrecen, Debrecen, Hungary.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Barta
authors.affiliation: MTA-DE Biodiversity and Ecosystem Services Research Group, University of Debrecen, Debrecen, Hungary.
authors.forename: Béla
authors.initials: B
authors.lastname: Tóthmérész
mesh_terms: D000818:Animals; D005075:Biological Evolution; D006790:Host-Parasite Interactions / Q000502:physiology*; D007814:Larva / Q000502:physiology; D010941:Plant Tumors / Q000469:parasitology*; D011235:Predatory Behavior / Q000502:physiology*; D027826:Rosa / Q000469:parasitology*; D014863:Wasps / Q000502:physiology