Interspecific Pollen Loss by Hummingbirds Visiting Flower Mixtures: Effects of Floral Architecture

Abstract

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Field evidence of strong differential pollen placement by Old World bat-pollinated plants

“…Additionally, previous field studies have typically collected pollen from a single time interval, without examining whether pollen patterns on the pollinators' bodies change throughout the foraging period (but see Howell, 1977). Our findings provide empirical evidence that differential pollen placement can occur in nature, in spite of processes known to diminish these patterns such as grooming (Thomson, 1986;Inouye et al, 1994;Harder and Wilson, 1998;Flanagan et al, 2009) or contact with various plant surfaces (Waser, 1983;Murcia and Feinsinger, 1996;Mitchell et al, 2009).…”

“…By placing pollen on different areas of a pollinator's body, plant species should lose less pollen to heterospecific flowers (improving male fitness) and receive less heterospecific pollen on stigmas (improving female fitness) (Waser, 1983;Morales and Traveset, 2008;Muchhala and Thomson, 2012;Stewart and Dudash, 2016a). However, support for the importance and effectiveness of differential pollen placement has been mixed (Howell, 1977;Armbruster et al, 1994;Murcia and Feinsinger, 1996;Muchhala and Potts, 2007;Flanagan et al, 2009;Muchhala and Thomson, 2012;Stewart and Dudash, 2016a).…”

“…For example, Murcia and Feinsinger (1996) found that even heterospecific plants with widely different floral morphologies can interfere with pollen movement between conspecific flowers, since heterospecific corollas and other plant structures can brush pollen off the bodies of pollinators. Additionally, pollen may be lost or spread across different body parts during grooming (Thomson, 1986;Inouye et al, 1994;Harder and Wilson, 1998;Flanagan et al, 2009).…”

Feeding behavior of hummingbirds and perching birds on Erythrina speciosa Andrews (Fabaceae) flowers in an urban area, Londrina, Paraná, Brazil

“…Nectar characteristics, patterns of secretion and availability, flower production, spatial arrangement, and morphological aspects of flowers and flower-visiting birds are important in order to understand the foraging behavior of birds on flowers (FEINSINGER & COLWELL 1978, WASER 1983, KEARNS & INOUYE 1993, as well as the consequences on pollen flow and seed set (MURCIA & FEINSINGER 1996, FRANCESCHINELLI & BAWA 2000.…”

Comportamento fenológico de três espécies de Jatropha (Euphorbiaceae) da Caatinga, semi-árido do Brasil

“…Esse resultado está de acordo com a hipótese de Seghieri et al (1995) Alguns autores sugerem que a sobreposição de floração sempre induz à diminuição na produção de frutos devido à competição por polinizadores e à perda de pólen nas flores de outras espécies (e.g. Campbell 1985, Murcia & Feinsinger 1996. Entretanto, esse parece não ser o caso das espécies estudadas no presente trabalho, já que são polinizados principalmente por Apis mellifera, muito abundante na área (Neves 2008).…”