Vibrating donor-partners during trophallaxis modulate associative learning ability of food receivers in the stingless bee Melipona quadrifasciata

MC CABE, SOFIA; HRNCIR, MICHAEL; FARINA WALTER M.

LEARNING AND MOTIVATION

ACADEMIC PRESS

Lugar: United States; Año: 2015 vol. 50 p. 11 - 21

0023-9690

Multiple sensory modalities within a communication context lead to an increased 23 responsiveness of the receptor. Due to this increase in attention when exposed to multiple 24 stimuli, it is possible that the learning ability of a receiver is modulated through 25 communication signals. Stingless bees (Apidae; Meliponini) are a good model to use in order 26 to investigate communication systems because they display a much wider behavioural 27 repertoire regarding foraging and communication than the thoroughly studied honeybee Apis 28 mellifera. Similar to honeybees, meliponine bees show appetitive unconditioned responses 29 (extension of the proboscis after contacting sugar with the antennae ) that may be 30 conditioned to odour. Such associative learning events take place within the nest, for 31 instance, when a successful forager unloads the nectar collected in the field to receiver 32 partners (trophallaxis). During these contacts, receivers obtain multimodal information about 33 the collected resource, such as its sugar content, its specific scent, and, in case of several 34 meliponine species such as Melipona quadrifasciata, thoracic pulsed vibrations produced by 35 the food donors. These vibrations correlate with the profitability of the resource exploited by 36 the forager. With this in mind, we asked whether and to what extent food receivers in 37 stingless bee colonies (M. quadrifasciata) integrate this multimodal information ? vibratory-38 olfactory-gustatory ? while receiving food from foragers. We found that the scented food 39 elicited stronger vibrations (longer and more frequent vibrations with an overall higher duty 40 cycle) than unscented food of equal sugar content. We also observed a positive correlation 41 between the amount of vibrations a bee received during trophallaxis and its subsequent 42 learning performance in a proboscis extension response conditioning procedure. Our 43 findings suggest that the vibrations during trophallaxis affect the receiver?s behaviour by 44 modulating its ability to establish the food-odour association.