When is it necessary to avoid your enemies? A stingless bee ignores aggressive competitor cues to explore food sources

Abstract

Social insects have the ability to perform tasks in an organized way. Communication plays a key role in controlling these processes, and throughout evolution, these organisms developed a complex system for transferring information. Different stingless bee species use the same resource during foraging that could lead to an eventual competition. It is important for organisms to access the costs of confrontation with rival individuals and the energetic gain from foraging when exploiting a food source. Thus, the present work aimed to investigate behavioral responses in the foraging activity of Plebeia droryana Friese, 1900 in the presence of chemical and visual cues of Trigona spinipes Fabricius, 1793. Foragers of P. droryana were trained to visit artificial feeders with two different sugar concentrations and were exposed to chemical and visual cues of T. spinipes at different setups, but always separately. We also identified the cuticular hydrocarbons (CHCs) of T. spinipes foragers. Both visual and chemical cues from T. spinipes did not cause P. droryana to decrease its foraging activity at 50% sucrose concentration. We found that 40% concentration caused bees to reduce the foraging effort when faced with visual cues from T. spinipes. Thus, similar to other species, we found that P. droryana was attracted to the food source containing a 50% sugar solution regardless of the presence of T. spinipes chemical cues. Based on our results, we infer that food quality is the most important factor when P. droryana foragers are exploiting a food source.