Yazar "Sytsma, Kenneth J." seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • [ X ]
    Öğe
    Pollination Ecology, Specialization, and Genetic Isolation in Sympatric Bee-PollinatedSalvia(Lamiaceae)
    (UNIV CHICAGO PRESS, 2020) Celep, Ferhat; Atalay, Zeynep; Dikmen, Fatih; Dogan, Musa; Sytsma, Kenneth J.; Classen-Bockhoff, Regine
    Premise of research. Previous pollination ecology studies ofSalviahave shown that there is low specialization for certain subgroups of bees and that pollinator number varies with species and locality. We studied 12Salviaspecies (three clades with different corolla morphologies and staminal lever mechanisms) that in part co-occur and coflower to examine prezygotic isolation mechanisms and the degree of specialization versus generalization in pollination ecology. Methodology. Pollinators were identified using field observations, photos, and related literature across three sites in Turkey. Video documentation of the visitation rate and the site of pollen placement on the pollinator body, morphometric measurements between flowers and pollinators, flowering time, flower color, handling time, and stigma contact ratio were analyzed. Plant-pollinator networks were constructed. Pivotal results. Mechanical, phenological, and ethological isolation occurs among sympatricSalviaspecies. A morphological fit is evident between flower tube length and the proboscis length of the main pollinators. Pollinator networks indicate that most species are ecological generalists and that only a few are specialists. Conclusions. The 12Salviaspecies, though phenotypically and functionally specialized by their zygomorphic, bilabiate flowers and bee-pollination syndrome, differ in the degree of their ecological specialization. Most of the sympatricSalviaspecies tend to be ecologically generalized, with two or more main pollinators and a few additional secondary pollinators, while a fewSalviaspecies are clearly specialized. Some floral traits (e.g., flower color, morphology, size, corolla tube length and width of the corolla tube entrance, type and size of the staminal lever mechanism, small numbers of flowers in the inflorescence), a short flowering time, and a small population size appear to be correlated with the degree of ecological specialization.
  • Küçük Resim
    Öğe
    Pollinator shifts, contingent evolution, and evolutionary constraint drive floral disparity inSalvia(Lamiaceae): Evidence from morphometrics and phylogenetic comparative methods
    (WILEY, 2020) Kriebel, Ricardo; Drew, Bryan; Gonzalez-Gallegos, Jesus G.; Celep, Ferhat; Heeg, Luciann; Mahdjoub, Mohamed M.; Sytsma, Kenneth J.
    Switches in pollinators have been argued to be key drivers of floral evolution in angiosperms. However, few studies have tested the relationship between floral shape evolution and switches in pollination in large clades. In concert with a dated phylogeny, we present a morphometric analysis of corolla, anther connective, and style shape across 44% of nearly 1000 species ofSalvia(Lamiaceae) and test four hypotheses of floral evolution. We demonstrate that floral morphospace of New World (NW)Salviais largely distinct from that of Old World (OW)Salviaand that these differences are pollinator driven; shifts in floral morphology sometimes mirror shifts in pollinators; anther connectives (key constituents of theSalviastaminal lever) and styles co-evolved from curved to linear shapes following shifts from bee to bird pollination; and morphological differences between NW and OW bee flowers are partly the legacy of constraints imposed by an earlier shift to bird pollination in the NW. The distinctive staminal lever inSalviais a morphologically diverse structure that has evolved in concert with both the corolla and style, under different pollinator pressures, and in contingent fashion.