Social network theory in the behavioural sciences: potential applications

Abstract

Social network theory has made major contributions to our understanding of human social organisation but has found relatively little application in the field of animal behaviour. In this review, we identify several broad research areas where the networks approach could greatly enhance our understanding of social patterns and processes in animals. The network theory provides a quantitative framework that can be used to characterise social structure both at the level of the individual and the population. These novel quantitative variables may provide a new tool in addressing key questions in behavioural ecology particularly in relation to the evolution of social organisation and the impact of social structure on evolutionary processes. For example, network measures could be used to compare social networks of different species or populations making full use of the comparative approach. However, the networks approach can in principle go beyond identifying structural patterns and also can help with the understanding of processes within animal populations such as disease transmission and information transfer. Finally, understanding the pattern of interactions in the network (i.e. who is connected to whom) can also shed some light on the evolution of behavioural strategies.

Keywords: Cooperation; Disease transmission; Information transfer; Mate choice; Social networks; Social organisation.

Fig. 1

Example of a social network where nodes (black circles) symbolise individuals and edges (lines) social connections between them. This fictitious network comprises 17 individuals (labelled a–p). See Table 1 for individual-based measures

Fig. 2

Social networks of Trinidadian guppies with males in black and females in white (Croft et al. 2006). The original network (a) in which all interactions are displayed was filtered so that (b) only those interactions are shown that occurred twice or more or (c) thrice or more. The latter (c) was a good indicator of cooperative interactions between pairs of individuals during predator inspection behaviour

Fig. 3

a Social network of Trinidadian guppies taken from two inter-connected pools in the Arima River. Individuals interconnected by lines were found at least twice together. b Five communities were detected in this system using simulated annealing (see Croft et al. for details of the method). The nodes are shaped according to which of the five communities they were found to be in (filled squares, filled inverted triangles, filled triangles, empty diamonds and empty circles)

Fig. 4

Different network positions of individuals and their potential influence on information transmission through a population. In a, a peripheral individual becomes the source of information and in b, a central individual

Fig. 5

Network motifs are local structural configurations in networks such as dyads and triads. Here is an example of a directed network with some possible configurations (modified from Faust and Skvoretz 2002)

Fig. 6

Differences in network structure between different contexts in fictitious human networks: information services network and military command. The number of individuals is the same, but the way in which they are linked differs (modified from Wilson 1975)