The interaction of temperature and sucrose concentration on foraging preferences in bumblebees
- 754 Downloads
Several authors have found that flowers that are warmer than their surrounding environment have an advantage in attracting pollinators. Bumblebees will forage preferentially on warmer flowers, even if equal nutritional reward is available in cooler flowers. This raises the question of whether warmth and sucrose concentration are processed independently by bees, or whether sweetness detectors respond to higher sugar concentration as well as higher temperature. We find that bumblebees can use lower temperature as a cue to higher sucrose reward, showing that bees appear to process the two parameters strictly independently. Moreover, we demonstrate that sucrose concentration takes precedence over warmth, so that when there is a difference in sucrose concentration, bees will typically choose the sweeter feeder, even if the less sweet feeder is several degrees warmer.
KeywordsPollination Sensory ecology Sensory integration Sweetness detection
We thank Tom Collett and Simon Laughlin for discussions and Lucy Sandbach and David Prince for help with data collection. The project is funded by NERC grant NE/C000552/1. AGD is supported by ARC DP0878968.
- Génotelle J (1978) Expression de la viscosité des solutions sucrées. Ind Aliment Agric 95:747–755Google Scholar
- Grandi G (1961) The hymenopterous insects of the superfamily Chalcidoidea developing within the receptacles of figs. Boll Ist Entomol Univ Studi Bologna 26:1–3Google Scholar
- Heinrich B, Esch H (1994) Thermoregulation in bees. Am Sci 82:164–170Google Scholar
- Kevan PG (1989) Thermoregulation in arctic insects and flowers: Adaptation and co-adaptation in behaviour, anatomy, and physiology. In: Mercer, J (eds) Thermal physiology. Elsevier (Biomedical Division), Amsterdam, pp 747–753Google Scholar
- Menzel R, Chittka L, Eichmüller S, Geiger K, Peitsch D, Knoll P (1990) Dominance of celestial cues over landmarks disproves map-like orientation in honey bees. Z Naturforsch 45c:723–726Google Scholar
- Pye D (in press) To add another hue unto the rainbow—near ultraviolet in nature. Optics and Laser TechnologyGoogle Scholar
- Rands SA, Whitney HM (2008). Floral temperature and optimal foraging: is heat a feasible floral reward for pollinators? PLoS ONE 3(4):e2007. DOI 10.1371/journal.pone.0002007
- Seeley TD (1995) The wisdom of the hive. Harvard University Press, CambridgeGoogle Scholar
- von Frisch K (1967) The dance language and orientation of bees. Harvard University Press, CambridgeGoogle Scholar