Journal of Insect Behavior, Vol. 14, No. 1, 2001 Evidence for Handedness in Bumblebees Andrea R. Kells 1,2 and Dave Goulson 1 Accepted June 28, 2000; revised August 7, 2000 We describe a simple study of how bumblebees ( Bombus spp.) behave when visiting florets which are arranged in a circle around a vertical inflorescence. In four species of bees, individuals showed a tendency for rotation in the same direction around each inflorescence on successive visits, i.e., each individual tended to go either clockwise or anticlockwise. Similar behavior has also been observed in mammals including humans. The implications of this tendency to repeat tasks in the same way are discussed, particularly in relation to our understanding of the phenomenon known as flower constancy. In humans, the tendency for individuals to turn in a particular direction is strongly related to handedness. In three of the four bee species there was a significant overall tendency for the bees to rotate in a preferred direction, suggesting that they too may exhibit handedness. KEY WORDS: Bombus; rotation; foraging; nectar; handling; flower constancy. INTRODUCTION Bee foraging behavior has proved to be a fruitful and popular area of re- search, and studies in this area have greatly improved our understanding of the learning and memory capacities of insects (Menzel et al., 1993; Chittka, 1998; Menzel, 1999). Bees have the ability to learn associations between sensory stimuli, such as visual and olfactory cues, and rewards, so that they can recognize rewarding flowers (Menzel and Erber, 1978). They learn 1 Division of Biodiversity and Ecology, School of Biological Sciences, University of Southamp- ton, Biomedical Sciences Building, Bassett Crescent East, Southampton SO16 7PX, U.K. 2 To whom correspondence should be addressed. Fax: +44-2380-594269. e-mail: andrea.kells@ soton.ac.uk. 47 0892-7553/01/0100-0047$19.50/0 C  2001 Plenum Publishing Corporation