Social network analysis in the study of nonhuman primates: a historical perspective

Abstract

Advances over the last 15 years have made social network analysis (SNA) a powerful tool for the study of nonhuman primate social behavior. Although many SNA-based techniques have been only very recently adopted in primatological research, others have been commonly used by primatologists for decades. The roots of SNA also stem from some of the same conceptual frameworks as the majority of nonhuman primate behavioral research. The rapid development of SNA in recent years has led to questions within the primatological community of where and how SNA fits within this field. We aim to address these questions by providing an overview of the historical relationship between SNA and the study of nonhuman primates. We begin with a brief history of the development of SNA, followed by a detailed description of the network-based visualization techniques, analytical methods and conceptual frameworks which have been employed by primatologists since as early as the 1960s. We also introduce some of the latest advances to SNA, thereby demonstrating that this approach contains novel tools for the study of nonhuman primate social behavior which may be used to shed light on questions that cannot be addressed fully using more conventional methods.

Figure 1

a. Sociogram of a rhesus macaques grooming network, reproduced following Sade (1965, Figure 3), b. Spring-embedded version of Sade’s sociogram generated in Netdraw. The individual with the highest centrality (‘1957’) is placed in the center of the spring-embedded graph. In both sociograms, circles represent females, triangles males. Lines between nodes represent the presence of a grooming tie. Arrows indicate the direction of grooming (i.e. given or received) and the weight of lines indicate the relative frequency at which grooming occurred.

Figure 2

Schematic representation of Hinde’s conceptual framework for the study of nonhuman primate social behavior, reproduced following Hinde (1976, Figure 1). Relationships between individuals emerge from the patterning of their interactions, and social structure emerges from the patterning of relationships. Social structure consequently feeds back to influence relationships and interactions, and relationships feedback to influence interactions. In this schematic, interactions are grouped according to type; for example, affiliative, agonistic and sexual interactions, while relationships are grouped according to the types of individuals involved; for example, mother-infant, male-female and kin-based relationships.