An introduction to the special column on animal social networks

The use of social network analysis to examine the behavior of social animals has grown rapidly in the past decade. Highly accessible books introducing network analysis techniques to the animal behavior research community (Croft et al., 2008; Whitehead, 2008) provide a gateway to the field. Furthermore, periodical reviews outlining the progress of the field and introducing both new biological questions and new analysis techniques (Krause et al. fertilize the growth of the use of social network analysis to study animal social behavior. This special column on animal social networks features papers that present methodological developments as well as new empirical examples of how social network analysis can be used to uncover insights about the organization of animal groups. The papers presented here range both in taxa and biological questions providing a diverse overview of current research on animal social networks. Three main themes that harness network theory to advance our understanding of social behavior emerge in this special column: (1) the first three papers (Dey et al., 2015; Hobson et al., 2015; and Beisner et al., 2015) compare networks over time and across biological situations to understand how social relations in a certain situation or at a particular life stage impact relations in a different situation or time; (2) the next three papers (Inghilesi et al., 2015; Pinter-Wollman, 2015; and Franz et al., 2015) discuss the impact of individual variation in behavior on the function of social groups; and (3) the last paper (Greening et al., 2015) provides a new method for examining the emergence of social processes from interactions among group members. The ability to compare among networks is fundamental for uncovering the ultimate consequences of social behavior. For example, comparing among social networks of different species can elucidate the environmental pressures that result in various social struc-Furthermore, it is often the case that more than one type of network is observed for a particular social group, for example a social group may have a grooming network which is different from an aggression network (Flack et al., 2006). Understanding how interaction networks that represent different situations relate to one another may shed light on emergent properties of the group such as its social stability. However, there is only little theory on how to compare social networks, and methods of data collection can have great implications on the reliability of such comparisons (Castles et al., 2014). In this special column, …