The role of personality in movement and reproductive differentiation in the termite Reticulitermes labralis

Animal personality traits play a key role in shaping individual behaviour and social differentiation. In the termite Reticulitermes labralis, workers display two distinct personality types when encountering heterospecific individuals. This study investigated how these personality types influence movement patterns and reproductive differentiation. Using individually marked workers and automated tracking, we quantified multiple movement parameters (speed, distance, time spent stationary, turning metrics and step length distributions) and compared them among shy workers, aggressive workers and queens. We found that shy workers exhibited lower locomotor activity and shorter movement distances than aggressive workers, suggesting that their movement patterns were highly similar to those of queens. Moreover, a subset of aggressive workers demonstrated plasticity by transitioning to shy-like behaviours following queen removal. Aggressive workers that rapidly transitioned to shy-like behaviour differentiated into supplementary reproductives earlier than those that transitioned later or remained aggressive, although the overall differentiation rate did not differ significantly. This suggests that personality traits and their plasticity play critical roles in mediating the transition from worker to reproductive status. The shift from aggression towards shyness serves as a transition point for reproductive differentiation, revealing how individual-level variation contributes to caste dynamics and social evolution in termite societies.