Relative effectiveness of insects versus hummingbirds as pollinators of Rubiaceae plants across elevation in Dominica, Caribbean

Author(s)

Lehmann, L. J. ^{[1, 2]} ; Maruyama, P. K. ^{[3, 4]} ; Bergamo, P. Joaquim ^{[3, 5]} ; Maglianesi, M. A. ^[6] ; Rahbek, C. ^[1] ; Dalsgaard, B. ^[1]

Affiliation

^[1] Univ Copenhagen, Nat Hist Museum Denmark, Ctr Macroecol Evolut & Climate, Univ Pk 15, DK-2100 Copenhagen - Denmark

^[2] Univ Copenhagen, Dept Biol, Sect Ecol & Evolut, Copenhagen - Denmark

^[3] Univ Estadual Campinas, Inst Biol, Dept Biol Vegetal, Campinas, SP - Brazil

^[4] Univ Fed Minas Gerais, ICB, Dept Biol Geral, Belo Horizonte, MG - Brazil

^[5] Univ Estadual Campinas, Inst Biol, Programa Posgrad Ecol, Campinas, SP - Brazil

^[6] Univ Estatal Distancia, Vicerrectoria Invest, San Jose - Costa Rica

• Document type: Journal article
• Source: Plant Biology; v. 21, n. 4, p. 738-744, JUL 2019.
• Web of Science Citations: 1

Abstract

Most angiosperms rely on animal pollination for reproduction, but the dependence on specific pollinator groups varies greatly between species and localities. Notably, such dependence may be influenced by both floral traits and environmental conditions. Despite its importance, their joint contribution has rarely been studied at the assemblage level. At two elevations on the Caribbean island of Dominica, we measured the floral traits and the relative contributions of insects versus hummingbirds as pollinators of plants in the Rubiaceae family. Pollinator importance was measured as visitation rate (VR) and single visit pollen deposition (SVD), which were combined to assess overall pollinator effectiveness (PE). In the wet and cool Dominican highland, we found that hummingbirds were relatively more frequent and effective pollinators than insects, whereas insects and hummingbirds were equally frequent and effective pollinators at the warmer and less rainy midelevation. Furthermore, floral traits correlated independently of environment with the relative importance of pollinators, hummingbirds being more important in plant species having flowers with long and wide corollas producing higher volumes of dilute nectar. Our findings show that both environmental conditions and floral traits influence whether insects or hummingbirds are the most important pollinators of plants in the Rubiaceae family, highlighting the complexity of plant-pollinator systems. (AU)

• FAPESP's process: 15/21457-4 - Linking macroecological patterns in ecological networks to functional traits of species: plant-hummingbird networks across the Americas
• Grantee: Pietro Kiyoshi Maruyama Mendonça
• Support Opportunities: Scholarships in Brazil - Post-Doctoral