title: Optimal concentrations in nectar feeding.
abstract: Nectar drinkers must feed quickly and efficiently due to the threat of predation. While the sweetest nectar offers the greatest energetic rewards, the sharp increase of viscosity with sugar concentration makes it the most difficult to transport. We here demonstrate that the sugar concentration that optimizes energy transport depends exclusively on the drinking technique employed. We identify three nectar drinking techniques: active suction, capillary suction, and viscous dipping. For each, we deduce the dependence of the volume intake rate on the nectar viscosity and thus infer an optimal sugar concentration consistent with laboratory measurements. Our results provide the first rationale for why suction feeders typically pollinate flowers with lower sugar concentration nectar than their counterparts that use viscous dipping.
authors.affiliation: Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Wonjung
authors.initials: W
authors.lastname: Kim
authors.forename: Tristan
authors.initials: T
authors.lastname: Gilet
authors.forename: John W M
authors.initials: JW
authors.lastname: Bush
mesh_terms: D000818:Animals; D001516:Bees / Q000033:anatomy & histology / Q000502:physiology*; D001696:Biomechanical Phenomena; D002241:Carbohydrates / Q000737:chemistry; D004327:Drinking Behavior / Q000502:physiology*; D008404:Massachusetts; D008855:Microscopy, Electron, Scanning; D008954:Models, Biological; D057048:Plant Nectar / Q000737:chemistry*; D054817:Pollination / Q000502:physiology; D013997:Time Factors; D014059:Tongue / Q000648:ultrastructure; D014741:Video Recording; D014783:Viscosity
chemical_list: D002241:Carbohydrates; D057048:Plant Nectar