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Home / Equine Research Bank / Sci Rep / Aerial drone observations identified a multilevel society in...
Scientific reports2021; 11(1); 71; doi: 10.1038/s41598-020-79790-1

Aerial drone observations identified a multilevel society in feral horses.

Abstract: The study of non-human multilevel societies can give us insights into how group-level relationships function and are maintained in a social system, but their mechanisms are still poorly understood. The aim of this study was to apply spatial association data obtained from drones to verify the presence of a multilevel structure in a feral horse society. We took aerial photos of individuals that appeared in pre-fixed areas and collected positional data. The threshold distance of the association was defined based on the distribution pattern of the inter-individual distance. The association rates of individuals showed bimodality, suggesting the presence of small social organizations or "units". Inter-unit distances were significantly smaller than those in randomly replaced data, which showed that units associate to form a higher-level social organization or "herd". Moreover, this herd had a structure where large mixed-sex units were more likely to occupy the center than small mixed-sex units and all-male-units, which were instead on the periphery. These three pieces of evidence regarding the existence of units, unit association, and stable positioning among units strongly indicated a multilevel structure in horse society. The present study contributes to understanding the functions and mechanisms of multilevel societies through comparisons with other social indices and models as well as cross-species comparisons in future studies.
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Publication Date: 2021-01-08 PubMed ID: 33420148PubMed Central: PMC7794487DOI: 10.1038/s41598-020-79790-1Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research involves the use of drone technology to investigate and understand the multilevel society structure of feral horses.

Research Purpose

The primary aim of this investigation was to discover the existence of a multilevel society in a group of feral horses using new technology – drones. The researchers aimed to delve into the nuances of non-human multilevel societies, such as that of feral horses, to gain insights into their social structuring, behavioral patterns, and relationships.

Research Method

  • The researchers used drones to take aerial photos of the feral horses in pre-determined areas. The ability to observe from above provided a broader, non-intrusive perspective that is not possible to achieve with traditional ground level observation methods.
  • Focusing on the proximity between the horses, they collected data on their positional attributes. They used the distance between the horses to create thresholds for defining associations.

Findings

  • The collected data inferred a bimodal distribution of association rates among the horses, indicating the existence of smaller social units within the larger group.
  • Smaller social units (or “units”) were found to exist within larger social groups (or “herds”). The researchers discovered that the distance between units was significantly less than expected in randomly replaced data, suggesting deliberate maintenance by the horses.
  • Interestingly, the research found that these herds had a specific order. Larger mixed-sex units occupied the central positions while smaller mix-sex units and all-male-units were situated on the periphery.

These results strongly suggest the existence of a multilevel social structure within feral horse societies.

Implications of the Research

The observations made in this study contribute significantly to understanding not only the social structure of horse societies, but also provides foundational comparative data for future studies examining other non-human animal societies. Researchers can further utilize this understanding to develop more comprehensive models predicting non-human group behaviors and interactions, such as decision making, social affiliations, and spatial arrangement.

Cite This Article

APA
Maeda T, Ochi S, Ringhofer M, Sosa S, Sueur C, Hirata S, Yamamoto S. (2021). Aerial drone observations identified a multilevel society in feral horses. Sci Rep, 11(1), 71. https://doi.org/10.1038/s41598-020-79790-1

Publication

Scientific reports
ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 11
Issue: 1
Pages: 71
PII: 71

Researcher Affiliations

Maeda, Tamao
  • Wildlife Research Centre, Kyoto University, 2-24 Tanaka-Sekiden-cho, Sakyo, Kyoto, Japan. tamao@powarch.com.
Ochi, Sakiho
  • Wildlife Research Centre, Kyoto University, 2-24 Tanaka-Sekiden-cho, Sakyo, Kyoto, Japan.
Ringhofer, Monamie
  • Institute for Advanced Study, Kyoto University, Yoshida Ushinomiya-cho, Sakyo, Kyoto, Japan.
Sosa, Sebastian
  • Université de Strasbourg, CNRS, IPHC, UMR 7178, Strasbourg, France.
Sueur, Cédric
  • Université de Strasbourg, CNRS, IPHC, UMR 7178, Strasbourg, France.
  • Institut Universitaire de France, Paris, France.
Hirata, Satoshi
  • Wildlife Research Centre, Kyoto University, 2-24 Tanaka-Sekiden-cho, Sakyo, Kyoto, Japan.
Yamamoto, Shinya
  • Institute for Advanced Study, Kyoto University, Yoshida Ushinomiya-cho, Sakyo, Kyoto, Japan. shinyayamamoto1981@gmail.com.

MeSH Terms

  • Aircraft
  • Animals
  • Female
  • Horses / psychology
  • Male
  • Photography
  • Social Behavior

Grant Funding

  • LGP-U04 / Japan Society for the Promotion of Science
  • KAKENHI, No. 18K18342 / Japan Society for the Promotion of Science
  • KAKENHI No. 18H05524 / Japan Society for the Promotion of Science
  • KAKENHI No. 15H05309 / Japan Society for the Promotion of Science
  • SPIRITS / Kyoto University

Conflict of Interest Statement

The authors declare no competing interests.

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Citations

This article has been cited 6 times.
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