Biology subjects

Avargues-Weber, A.

Publications and source records attributed to Avargues-Weber, A..

4 recordsLinked to original sources

bioRxiv2026

A numerical bias in honeybees: Numerousness is more salient than space and size non-numerical cues during quantity discrimination.

Despite growing evidence that many animals can evaluate quantities, the ecological relevance of numerical cognition remains debated, particularly outside vertebrates. Would individuals still rely on numerousness if less computationally demanding cues, visual features extracted at the early stage of visual processing, were available to assess quantity? In primates, individuals show a numerical bias as they tend to rely on the number of items rather than non-numerical cues, such as total area, to categorize quantities. In this study, we trained free-flying honeybees to discriminate between two and four items in conditions where numerosity covaried with the total area and perimeter (Experiment Size) or the convex hull (Experiment Space) cues, mimicking ecological contexts. Transfer tests assessed which numerical or non-numerical cues were learned and preferentially used by the bees. Bees primarily relied on numerousness over these non-numerical cues. Individual analyses revealed two consistent strategies: a "numerical bias" strategy, in which bees encoded numerical information while ignoring non-numerical cues, and a "generalist" strategy, where bees flexibly switched between cues and favored non-numerical information when cues conflicted. We further reported improved discrimination when smaller quantities appeared on the left and larger ones on the right, consistent with an oriented mental number line. Together, these findings demonstrate a spontaneous numerical bias in honeybees and reveal that individuals within the same species can adopt distinct strategies when evaluating quantity. Our findings also suggest that distantly related taxa like bees and primates may have independently evolved comparable mechanisms for quantity evaluation.

animal behavior and cognition↗

bioRxiv2024

Interindividual variability in flower pickiness by foraging bumblebees

Pollinators navigate complex and heterogeneous "flower markets", where floral resources vary in quality, availability, and spatial distribution. Bumblebees, as generalist foragers, visit numerous flowers during their foraging bouts, yet the factors influencing their flower choices and the individual differences in foraging behaviour remain poorly understood. Here, we tested how bees adjust their foraging in response to different reward structures. Bombus terrestris workers completed three foraging bouts in two artificial flower environments: one simulating a favourable environment with patches alternating high- and low-quality flowers (40% vs. 20% w/w sucrose solution), and the other a challenging environment with high-quality flowers alongside unrewarded ones (40% w/w sucrose solution vs. plain water). We hypothesised that bees would improve their foraging efficiency in both environments, but more rapidly in the more extreme one, where the greater reward difference creates stronger pressure to learn quickly. In both conditions, bees increased their sucrose intake per unit time over bouts. We also observed consistent differences in flower selectivity among individuals: in the favourable environment, bees that first visited high-quality flowers focused on them and avoided low-quality ones (became "picky"), while bees that first visited low-quality flowers kept visiting both types. Despite these differences, bees across environments and pickiness levels all reached similar sucrose intake rates by the third foraging bout, either by becoming more selective, collecting more sucrose solution, or reducing time spent foraging. These findings highlight the adaptability of bee foraging and suggest that early flower experiences may contribute to lasting individual differences in foraging behaviour. Significance statementBumblebees are highly efficient pollinators of wild plants and commercial crops, yet their foraging behaviour varies notably among individuals. Understanding why bees differ in their foraging decisions is crucial, as it affects how they collect resources. We show that individual Bombus terrestris workers rapidly adapt to flower patches with different reward qualities. Remarkably, a bees first flower visits have lasting effects: individuals that started with high-quality flowers consistently favoured them and avoided low-quality ones, while those that started with low-quality flowers continued to visit both types over time. Despite these differences, bees reached similar nectar intake rates after just three foraging trips, regardless of how selective they were. Our findings show that bees can quickly adjust their foraging behaviour, and that early experiences play a key role in how they exploit resources across different environments.

animal behavior and cognition↗

bioRxiv2021

Bees can be trained to identify SARS-CoV-2 infected samples.

The COVID-19 pandemic has illustrated the need for the development of fast and reliable testing methods for novel, zoonotic, viral diseases in both humans and animals. Pathologies lead to detectable changes in the Volatile Organic Compound (VOC) profile of animals, which can be monitored, thus allowing the development of a rapid VOC-based test. In the current study, we successfully trained honeybees (Apis mellifera) to identify SARS-CoV-2 infected minks (Neovison vison) thanks to Pavlovian conditioning protocols. The bees can be quickly conditioned to respond specifically to infected minks odours and could therefore be part of a wider SARS-CoV-2 diagnostic system. We tested two different training protocols to evaluate their performance in terms of learning rate, accuracy and memory retention. We designed a non-invasive rapid test in which multiple bees are tested in parallel on the same samples. This provided reliable results regarding a subjects health status. Using the data from the training experiments, we simulated a diagnostic evaluation trial to predict the potential efficacy of our diagnostic test, which yielded a diagnostic sensitivity of 92% and specificity of 86%. We suggest that a honeybee-based diagnostics can offer a reliable and rapid test that provides a readily available, low-input addition to the currently available testing methods. A honeybee-based diagnostic test might be particularly relevant for remote and developing communities that lack the resources and infrastructure required for mainstream testing methods.

microbiology↗

bioRxiv2018

Higher-order discrimination learning by honey bees in a virtual environment

Non-elemental learning constitutes a cognitive challenge because, contrary to elemental learning forms, it does not rely on simple associations, as events to be learned are usually ambiguous in terms of reinforcement outcome. Negative patterning constitutes a paradigmatic case of non-elemental learning, as subjects have to learn that single elements A and B are reinforced while their conjunctive representation AB is not reinforced (A+, B+ vs. AB-). Solving this problem requires treating the compound AB as being different from the linear sum of its components in order to overcome stimulus ambiguity (A+/A- and B+/B-). The honey bee is the only insect capable of mastering negative patterning as shown by numerous studies restricted mainly to the olfactory domain. Here we studied the capacity of bees to solve a negative patterning discrimination in the visual domain and used to this end a virtual reality (VR) environment in which a tethered bee walking stationary on a treadmill faces visual stimuli projected on a semicircular screen. Stimuli are updated by the bees movements, thus creating an immersive environment. Bees were trained to discriminate single-colored gratings rewarded with sucrose solution (blue, green; A+, B+) from a non-rewarded composite grating (blue-green, AB-). Bees learned this discrimination in the VR environment and inhibited to this end linear processing of the composite grating, which otherwise is treated as the sum of its components. Our results show for the first time mastering of a non-linear visual discrimination in a VR environment by honey bees, thus highlighting the value of VR for the study of cognition in insects.

animal behavior and cognition↗