caa a22 4500 606193383 CHVBK 20210128100909.0 cr unu---uuuuu 210128e20150501xx s 000 0 eng 10.1007/s10682-014-9718-7 doi (NATIONALLICENCE)springer-10.1007/s10682-014-9718-7 Nectar palatability can selectively filter bird and insect visitors to coral tree flowers [Elektronische Daten] [Susan Nicolson, Sara Lerch-Henning, Megan Welsford, Steven Johnson] Secondary compounds in nectar may play a decisive role in determining the spectrum of floral visitors on plants. Flowers of the African coral tree Erythrina caffra are visited mainly by generalist passerine nectarivores, such as weavers and bulbuls. As the nectar of this species tastes very bitter to humans, it was hypothesized that secondary compounds may repel sunbirds and honeybees which are common in the same habitats yet seldom consume the nectar. We conducted choice tests using fresh nectar and both sucrose and hexose (glucose/fructose) solutions of the same concentration as the nectar. White-bellied Sunbirds (Cinnyris talatala) were repelled by nectar of both E. caffra and a related species Erythrina lysistemon, but Dark-capped Bulbuls (Pycnonotus tricolor) did not discriminate between the Erythrina nectar and control sugar solution in terms of amounts consumed. Honeybees (Apis mellifera scutellata) probed exposed droplets of E. caffra nectar and a control sugar solution at the same rate, suggesting that there is no volatile deterrent, but they immediately withdrew their proboscis far more often from the droplets of Erythrina nectar than they did from the sugar solution, suggesting that they find Erythrina nectar distasteful. These results contribute to a growing awareness that non-sugar components of nectar can play important functional roles in plant pollination systems. Springer International Publishing Switzerland, 2014 Bird pollination nationallicence Bitter nectar nationallicence Dilute nectar nationallicence Erythrina nationallicence Generalist nectarivores nationallicence Nicolson Susan Department of Zoology and Entomology, University of Pretoria, Private Bag X20, 0028, Hatfield, South Africa aut Lerch-Henning Sara Department of Zoology and Entomology, University of Pretoria, Private Bag X20, 0028, Hatfield, South Africa aut Welsford Megan School of Life Sciences, University of KwaZulu Natal, P/Bag X01, 3209, Scottsville, Pietermaritzburg, South Africa aut Johnson Steven School of Life Sciences, University of KwaZulu Natal, P/Bag X01, 3209, Scottsville, Pietermaritzburg, South Africa aut Evolutionary Ecology Springer International Publishing 29/3(2015-05-01), 405-417 0269-7653 29:3<405 2015 29 10682 https://doi.org/10.1007/s10682-014-9718-7 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10682-014-9718-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Nicolson Susan Department of Zoology and Entomology, University of Pretoria, Private Bag X20, 0028, Hatfield, South Africa aut NATIONALLICENCE 700 1- Lerch-Henning Sara Department of Zoology and Entomology, University of Pretoria, Private Bag X20, 0028, Hatfield, South Africa aut NATIONALLICENCE 700 1- Welsford Megan School of Life Sciences, University of KwaZulu Natal, P/Bag X01, 3209, Scottsville, Pietermaritzburg, South Africa aut NATIONALLICENCE 700 1- Johnson Steven School of Life Sciences, University of KwaZulu Natal, P/Bag X01, 3209, Scottsville, Pietermaritzburg, South Africa aut NATIONALLICENCE 773 0- Evolutionary Ecology Springer International Publishing 29/3(2015-05-01), 405-417 0269-7653 29:3<405 2015 29 10682