Collective Decision Making in Tibetan Macaques: How Followers Affect the Rules and Efficiency of Group Movement

Primate societies must undergo successful collective decision making during group movement to stay cohesive and provide the ecological and evolutionary benefits of sociality. This study investigates how a fan structure facilitates successful group movement in the YA1 group of Tibetan macaques (<em>Macaca thibetana</em>) at Mt. Huangshan National Reserve in Anhui, China. We used structural equation modeling (SEM) to determine the relative influences of sex, age, maternal kinship, dominance, and social network centrality on the number of fans (consistent followers) an individual had, and the number of group members an individual was a fan of (fandom). SEM revealed that dominant females had more fans, while younger, dominant individuals with more familial connections were fans of more individuals. Fans and fandom were most strongly influenced by dominance, displaying a strong network of females occupying top positions in the hierarchy who consistently followed each other. Rules used in affiliative interactions were maintained during movement to aid in successful collective decision making. In addition, we examined the relationship between the fan structure and movement efficiency. We found a positive regression between fans and efficiency (R²=0.402), and a negative correlation between fans and number of unsuccessful movements (Rs=-0.367), suggesting a link between the social connections maintained in a movement and the efficiency of the movement. Dominant females with more fans initiated less efficient movements because the complex fan structure slowed the joining process. However, individuals with more fans led fewer unsuccessful movements, suggesting a relationship between fans and initiation success. These findings displayed a complex network of social relationships within Tibetan macaque societies that were used during group movement organization to maintain cohesion and mediate the benefits of sociality.

Name thesis:degree_name

Master of Science (MS)

Discipline thesis:degree_discipline

Primate Behavior

Year dc:date.available

2017

Author dc:creator

• Rowe, Amanda

Contributors dc:contributor

• Lixing Sun
• Lori K. Sheeran
• R. Steven Wagner

• Tibetan macaque
• Macaca thibetana
• Collective Movement
• Fan
• Fandom
• Structural Equation Modeling
• Behavior and Ethology
• Biological and Physical Anthropology
• Zoology

Language dc:language

English

Repository record dc:identifier

https://digitalcommons.cwu.edu/etd/633

OAI identifier oai:identifier

oai:digitalcommons.cwu.edu:etd-1641