April 23, 2013
For The Rock Hyrax, A Balanced Triad Is Best Within The Social Group
April Flowers for redOrbit.com - Your Universe Online
Humans follow complex social situations to decide who to befriend or abandon. A new study that seeks to advance our understanding of the structure of animal social networks reveals that animals use the same level of sophistication in judging social configurations.
Published this week in Animal Behaviour, this study is the first to apply a long-standing theory of social psychology — called "structural balance," the theory analyzes human relationships — to an animal population in order to better understand the mechanisms underlying the structure of animal social groups. The scientists analyzed social bonds in behavioral data obtained from a long-term study of the rock hyrax, a small mammal that lives in colonies across Africa and the Middle East.
In structural balance theory, the positive and negative ties between three individuals, or triads, are considered. The theory suggests that "the friend of my enemy is my enemy" triangle configuration is more stable and more common than the "friend of my enemy is my friend" triangle. "The friend of my friend is my friend" is another stable configuration in the social network, while "the enemy of my enemy is my enemy" is an unstable state, according to the theory.
Structural balance theory has the ability to predict patterns in the structure of the whole social network, which is the potential power of the data gleaned. The theory can also predict changes that occur over time, as unstable triads are expected to change to stable ones.
"We all live in social networks of some kind, either online or offline, and we are interested in understanding how these groups form and dissolve and their internal dynamics, but while studying these human dynamics is important, it's also very difficult and in many cases impractical. So we study how sociality evolved in animals, which might offer us some insights into our own social behavior. And indeed, the structural balance theory that was developed to study human behavior appears to be relevant in animals as well," said Amiyaal Ilany, a postdoctoral fellow at the National Institute for Mathematical and Biological Synthesis.
The rock hyraxes observed tended to form balanced triads, and change unbalanced triads to balanced ones over time. New individuals in the population, such as new pups or males that migrated into the network, introduced social instability by forming often unbalanced triads. This caused the network as a whole to retain some level of instability. Contrary to classical structural balance theory, the study found that the "enemy of my enemy is my enemy" configuration was actually a stable configuration.
The study findings suggest that structural balance may play a role in the evolution of social structures by selecting against certain specific configurations. It may also serve as a psychological mechanism, allowing specific social structures to exist and preventing cooperation between members of different groups.
"The results indicated that changes in social relationships are dependent not only on two individuals, but significantly on third parties, which underscores the importance of structural balance theory in explaining the evolution of complex natural social systems," Ilany said, who was a doctoral student at Tel Aviv University when the research was begun.