THE SOCIOECOLOGICAL CORRELATES OF COLLECTIVE MOVEMENTS IN GIRAFFES

The emergence of collective behaviors within groups from potentially divergent individual behaviors and needs remains uninvestigated in many social species. Giraffes are known to exhibit substantial social fluidity, given the high degree of fission-fusion dynamics that shape their grouping patterns. However, the patterns and processes underlying giraffe collective movements are unknown. Using behavioral observations, we examined the influence of individual factors (sex and age), social context (group size and type), and habitat characteristics (open and closed) on the decision-making process that shapes giraffe collective movements and resultant group fission. We find that adult females exhibit a greater propensity to initiate group movements, whereas subadult individuals follow movements more quickly than other age groups. Within larger groups, decision-making leading to collective movements is slower than within smaller groups. Movements in larger groups are also more likely to result in group fission. These results contribute to a growing body of knowledge on the coordination of collective movement across species. By illuminating collective movement dynamics in an understudied large mammal species with a high degree of fission-fusion dynamics, we contribute to the potential for cross-species investigations into the mechanisms of collective behavior and the factors that drive inter- and intraspecific variation.