Expérimental
Collective motion is a fascinating observation where the ensemble of agents can be seen as a single living object that can deform, flow and merge. A wealth of approaches has been developed over the years to model such systems including discrete and continuous strategies. In this new project, we focus on an original system that has barely been studied in the frame of mechanics and not at all in terms of rheology: a honeybee cluster. When a colony divides, the queen bee and thousands of worker bees swarm out of the hive and form a cohesive structure similar to a liquid drop hanging on a wire. The intriguing apparent mechanical properties of bee crowds are reminiscent of cohesive grains, like wet sand. Unlike granular materials, bees are active and cognitive, each agent can intentionally adapt its own movements, in this perspective the system is a promising tool to tackle new questions in the field of cognitive active matter. Based on preliminary experiments, the intern will measure the flowing of living bee clusters through a constriction and try to quantify its physical properties as a living material. This is an interdisciplinary project with interactions with complex fluids physics, numerical modeling, active matter and ethology.