Abstract
Collective animal behavior emerges through interactions among individuals, yet research to date has largely assumed these individuals to be identical, neglecting the biological diversity that characterizes most real-world groups. We investigate the collective behavior of explicitly assembled heterogeneous groups of the predatory nematode Pristionchus pacificus. This nematode exhibits aggregation behavior on food patches and possesses a well-characterized kin-recognition system, making it a particularly powerful system for exploring how variation in interaction rules shapes collective dynamics. We find that heterogeneous social environments alter collective behaviors, driving spatial reorganization within mixed groups. We further demonstrate that this reorganization is mediated by biting interactions and show how individual biting events scale up to produce collective spatial organization. Finally, we introduce an individual-based model revealing that these interactions are both selective towards non-kin and asymmetric between different strains: meaning that one strain exerts a stronger influence on the behavior of the other. This work highlights the importance of considering individual-level behavioral responses to study collective behavior in heterogeneous groups and can yield new insights into how different P. pacificus strains interact in the natural environments.
About the speaker
Narcís is a PhD student in the lab of Serena Ding at the Center for the Advanced Study of Collective Behavior and the Max Planck Institute of Animal Behavior. He has a background in physics and has a wide-ranging interest in collective animal behavior. His current research focuses on using different nematodes as a model system to investigate how group composition, individual phenotypic traits and interaction mechanisms shape collective behavior in heterogeneous groups.