Oxytocin homogenizes horse group organization.
- Journal Article
Summary
The research investigates how the hormone oxytocin impacts the social organization of horse groups, finding it encourages a more evenly distributed social structure.
Objective of the Study
The researchers in this study aim to understand how the hormone oxytocin, which is often connected with social bonding and cohesion, influences the group-level social organization of horses. They conducted the study with 5 groups of horses (total 58 horses: 12 mares and 46 geldings).
Methodology
- The researchers administered exogenous intranasal oxytocin, an artificially-created version of the hormone, to the horses.
- They used GPS tracking devices and social network analysis to study the impact of the hormone on the horses’ movement and social interactions.
Findings
- The study found that oxytocin reduced differences across social levels. This means that interactions among the horses became more evenly distributed following the introduction of oxytocin.
- The hormone also altered existing social preferences among the horses. Instead of strengthening existing bonds, oxytocin led horses who rarely interacted to spend more time together. Conversely, horses who often associated with each other spent more time apart after oxytocin was introduced.
- Overall, the hormone led to a more distributed social structure among the horses and reduced clustering at the network level.
Significance of the Study
This investigation’s findings lend empirical support to the idea that oxytocin plays a crucial part in group cohesion and social organization among species. The researchers posit that this study contributes to our understanding of oxytocin’s role in collective behavior, social organization, as well as the evolution of group-based sociality across different species (taxa).
Cite This Article
Publication
Researcher Affiliations
- Institute for Advanced Study, Kyoto University, Kyoto, Japan.
- Wildlife Research Center, Kyoto University, Kyoto, Japan.
- Wildlife Research Center, Kyoto University, Kyoto, Japan.
- Research Center for Integrative Evolutionary Science, The Graduate University of Advanced Science (SOKENDAI), Hayama, Japan.
- Department of Animal Sciences, Teikyo University of Science, Tokyo, Japan.
- Institute for Advanced Study, Kyoto University, Kyoto, Japan.
- Wildlife Research Center, Kyoto University, Kyoto, Japan.
Conflict of Interest Statement
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