Modulation of trail laying in the ant Lasius neglectus (Hymenoptera: Formicidae) and its role in the collective selection of a food source

Abstract

In this study, we explored the feeding behaviour of the invasive garden ant Lasius neglectus. In particular, we investigated its ability to select the more profitable resource in a binary choice and its pheromonal trail marking. When facing a choice between two different energy sources, workers were rapidly recruited to the most profitable one, although both the speed of the recruitment and the number of ants varied considerably with the difference between the solutions. When facing two identical sources, workers were massively recruited onto one of the two in 80% of tests, whereas in the remaining 20% the workforce was split equally between the two. In the second experiment, we supplied a single food source and then assessed if the number of marks per ant was affected by solution concentration and direction of movement (nestward or foodward), and if it varied over time. Marking activity increased with solution concentration, was more intense in nestward‐moving ants, and decreased over time. All these effects, although significant, were not pronounced. However, the marking activity of the very first ants visiting the resource was more intense, and this seems to be sufficient to explain the collective selection of the most valuable resource. Finally, marks were not evenly distributed along the trail, but concentrated at some points. The behaviour of L. neglectus is partly comparable to that of Lasius niger, but appears to be more similar to that of other invasive ant species, suggesting a possible primary role of the marking behaviour in influencing the invasiveness of this species.

Trail Pheromone Does Not Modulate Subjective Reward Evaluation in Lasius niger Ants

“…Inadvertent social information also affects resource evaluation, with ants undervaluing resources consumed in the presence of other ants, and preferring odors associated with solitary feeding over those associated with group feeding in a binary choice assay . As in many other ants, L. niger deposit pheromone trails to food sources, and deposit more pheromone to resources they perceive as being of higher quality (Beckers et al, 1992;Detrain and Prieur, 2014;Frizzi et al, 2018;Wendt et al, 2019). Pheromone deposition is also depressed by repeatedly encountering nestmates on the trail or while feeding (Czaczkes et al, 2013b; or by trail pheromone already being present on the substrate (Czaczkes et al, 2013a).…”

Application of CO2 carbon stable isotope analysis to ant trophic ecology

“…This could explain the similarity found between L. neglectus and C. scutellaris breath. Although C. scutellaris preys on other insects, its main carbohydrate source is the plantderived aphid honeydew, as well as for L. neglectus (Frizzi et al, 2016(Frizzi et al, , 2018. One important point to carefully consider when dealing with the analysis of breathed CO 2 is that the δ 13 C value reflects the catabolized substrate.…”

“…The invasive garden ant Lasius neglectus (van Loon, Boomsma & Andrasfalvy) is a Formicinae ant considered invasive in Europe (Nagy et al, 2009). This species tends to monopolize aphid aggregations and to rely primarily on honeydew (Paris & Espadaler, 2009; Frizzi et al, 2018). Whereas seed collection (with elaiosome consumption) is common, members of few genera, such as the Myrmicinae Messor and Pheidole , actually eat them (Blüthgen & Feldhaar, 2010).…”

Effect of Starvation on the Feeding Activity Toward Sugary Food in the Ant Tapinoma nigerrimum (Nylander, 1856)

“…Finally, although carbohydrates are central resources for the ants, since the need for sugary sources may affect their behavior, from the interspecific interaction to the collective decision-making (e.g. Grover et al, 2007;Arganda et al, 2014;Sola & Josens, 2016;Frizzi et al, 2018;Wittman et al, 2018), an interesting improvement of the study would be to repeat the experiment with foods rich in fats or proteins, maybe including some different indicators in the analysis, such as hormone secretion, frequencies of trophallaxis and recruitment behavior. Moreover, we selected these experimental solutions on the basis of previous studies, which showed a clear scalar response of workers.…”