Data from: Similar but different: dynamic social network analysis highlights fundamental differences between the fission-fusion societies of two equid species, the onager and Grevy's zebra

Understanding why animal societies take on the form that they do has benefited from insights gained by applying social network analysis to patterns of individual associations. Such analyses typically aggregate data over long time periods even though most selective forces that shape sociality have strong temporal elements. By explicitly incorporating the temporal signal in social interaction data we re-examine the network dynamics of the social systems of the evolutionarily closely-related Grevy's zebras and wild asses that show broadly similar social organizations. By identifying dynamic communities, previously hidden differences emerge: Grevy's zebras show more modularity than wild asses and in wild asses most communities consist of solitary individuals; and in Grevy's zebras, lactating females show a greater propensity to switch communities than non-lactating females and males. Both patterns were missed by static network analyses and in general, adding a temporal dimension provides insights into differences associated with the size and persistence of communities as well as the frequency and synchrony of their formation. Dynamic network analysis provides insights into the functional significance of these social differences and highlights the way dynamic community analysis can be applied to other species.Grevy's zebra and wild asses affiliation groupsAffiliation groups over time for grevy's zebra and wild asses. Data in contains three columns: day, group no., individual id. Day is the day (an encoding of a date) on which the groups of animals have been sighted. Group no. is the unique group id for each sighted group. All animals with the same group no. have been seen together. All group numbers are unique and do not repeat across days. Animal id is the unique identifier of an individual animal. The letter after the id indicates demographic status: Grevy's [s- stallion, b - bachelor, n - non-lactating, l - lactating], wild asses [T - territorial male, N - non-lactating, L - lactating].Grevy-Onager-groups.cs