CASCB Talk: Drivers of individual behavioural diversity within collectives: two case studies in ants

Time
Monday, 22. January 2024
15:30 - 16:30

Location
ZT702 and online

Organizer
CASCB

Speaker:
Dr. Alba Motes Rodrigo, University of Lausanne

Join the talk on Zoom

Ants are ubiquitous across terrestrial ecosystems. This colonizing success is the result of a series of characteristics that make them unique in their ability to adapt to new habitats and flexibly cope with environmental change. These characteristics include a decentralized communication network and emergent traits such as division of labour. Division of labour is facilitated by the expression of diverse behavioural phenotypes and sensitivity thresholds within the colony that result in different groups of ants performing different tasks. Although the adaptive value of division of labour in social insects is well established, the role that socio-ecological factors play in modulating inter-individual behavioural variation within colonies, remain poorly understood. This talk will present two studies where we tackle this question using a state-of-the-art tracking system to automatically collect behavioural and spatial data.

In the first study, Dr. Alba Motes Rodrigo will present, how they tested how task engagement and worker density jointly affect worker behaviour in Leptothorax acervorum ants. To address this question, they developed a dual system that combined automated behavioural tracking with a robotic dummy that they used to provide standardized tactile stimuli to target individuals. Using this dual system, they found that task engagement and worker density have independent effects on worker behaviour. The results suggest that ants’ responsiveness and alarm behaviour are density-dependent and that ants experience a process of habituation to tactile stimulation over time. In addition, they found that ants’ probability to respond to the stimulation was dependent on the task the ant was engaged in when the stimulus was presented.

In the second study that Rodrigo will present, they explored how an individual’s behaviour and social environment changes when it suffers a physical disturbance (i.e., injury) in the carpenter ant Camponotus fellah. Pairing behavioural and social network analyses, they show that injured ants receive more attention than control ants in terms of woundcare, grooming and trophallaxis. In addition, injured ants become more peripheral in the colony’s network as a consequence of their injury although they maintain their nodal degree. They also show that injured individuals were predominantly tended by ants that shared space and social connections with them in the days preceding the injury.

Combined, these two studies provide new insights on the socio-ecological drivers of inter-individual behavioural variation in ant colonies and further our understanding of how decentralized systems self-regulate.

Dr. Alba Motes Rodrigo is currently a postdoctoral researcher at the Department of Ecology and Evolution of the University of Lausanne (Switzerland) in the Evolutionary Genetics and Ecology of Social Life Group. Her research focuses on linking individual and group level processes in social species. Currently, she is investigating social diffusion processes (epidemics and information flow) in a variety of ant species using automated data collection methods and social network analysis. During her PhD, she was part of the ERC STONECULT project, where she conducted cognitive experiments with great apes on stone knapping acquisition to recostruct how early hominins acquired their technological repertoires and cultures. Previously, she studied song acquisition and learning in norwegian pied flycatchers, tool-excavating behaviour in chimpanzees and primate laterality.