The proboscis extension reflex not elicited in Magachilid bees

Authors: VOREL, CORY - UTAH STATE UNIVERSITY; Pitts Singer, Theresa

Submitted to: Journal of Kansas Entomological Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/15/2009
Publication Date: 4/22/2010
Citation: Vorel, C.A., Pitts Singer, T. 2010. The proboscis extension reflex not elicited in Magachilid bees. Journal of Kansas Entomological Society. 83(1): 80-83.

Interpretive Summary: Honey bees will reflexively extend their proboscis (“tongue”) in response to their antennae being touched with a droplet of sugar-water solution. For decades, this proboscis extension reflex (PER) of honey bees has been used as a tool to further the understanding of bee “mental” processes, such as learning and memory, and revealing their neural and molecular foundations. The PER has also been used to demonstrate learning abilities of bumble bees and stingless bees. Our initial attempts to use simple PER elicitation procedures failed with the solitary blue orchard bee, although honey bees easily responded. The lack of response in blue orchard bees could have been due to the technique used or to particular characteristics of the species tested. To determine whether the technique used to elicit the PER from honey bees can be adapted for use with other bees, we tested variations of the traditional PER elicitation technique on several species of solitary and social bees and wasps. By fully or partially restraining their bodies but not their heads, we attempted to elicit the PER from honey bees, yellowjacket wasps, bumble bees, blue orchard bees, alfalfa leafcutting bees, and sunflower leafcutting bees. The social (colony-dwelling) bees and wasps responded to a drop of sugar-water touched to their antennae by extending their mouthparts. The solitary species never responded with the PER. Consequently, for answering questions about the mental processes of solitary bees, an alternative technique will have to be used and perhaps a different behavioral response will have to be sought.

Technical Abstract: Honey bees (Apis mellifera L.) will reflexively extend their proboscis in response to antennal stimulation with sucrose solution. For decades, the proboscis extension reflex (PER) of honey bees has been used as a tool to further the understanding of their cognitive processes, such as learning and memory, and revealing their neural and molecular foundations. The PER has also been used to demonstrate learning abilities of other social bees, bumble bees (Bombus) and stingless bees (e.g., Melipona). Our initial attempts to use simple PER elicitation procedures failed with the solitary blue orchard bee, O. lignaria Say (Hymenoptera: Megachildae), although honey bees readily responded. The lack of response in O. lignaria could have been due to procedural factors or species-specific factors. To determine whether the technique used to elicit the PER from honey bees can be adapted for use with other bees, we tested variations of the traditional PER elicitation technique on several species of Hymenoptera. By fully or partially restraining their bodies but not their heads, we attempted to elicit the PER from honey bees, Vespula spp. (yellowjacket wasps), Bombus spp. (bumble bees), O. lignaria, Megachile rotundata Fabricius (alfalfa leafcutting bee), and M. pugnata. The eusocial bees and wasps responded to a drop of sucrose touched to their antennae by extending their mouthparts. The solitary species never responded with the PER. Consequently, for answering questions about the cognitive processes of solitary bees, an alternative conditioning technique will have to be used and perhaps a different behavioral response will have to be sought.