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Home / Equine Research Bank / Biol Lett / Mean mares? Habitat features influence female aggression in ...
Biology letters2025; 21(1); 20240494; doi: 10.1098/rsbl.2024.0494

Mean mares? Habitat features influence female aggression in response to social instability in the feral horse (Equus caballus).

Abstract: It is unclear how habitat features alter animal responses to social instability. Only by uncovering such interactions can we fully understand the evolutionary drivers and fitness consequences of sociality. We capitalize on a management-induced manipulation of social stability in an island population of free-ranging feral horses (), living across three distinct habitat types. We tested whether female group-changing behaviour (a reliable measure of social instability) affected (i) female-female aggression, (ii) rank within female dominance hierarchies, (iii) stability of female hierarchies (in the groups they joined and/or left), and (iv) how habitat characteristics shaped these responses. Female group-changing behaviour positively predicted aggression from other females, but only when habitat features such as visibility and freshwater distribution were considered. We found no strong association among female group-changing behaviour and the aggression initiated, female rank or the stability of female dominance hierarchies. Our work reveals that animal responses to social instability are nuanced and impacted by the surrounding habitat. A better understanding of these impacts can help elucidate evolutionary drivers of sociality and mitigate unintended effects of management practices.
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Publication Date: 2025-01-15 PubMed ID: 39812012PubMed Central: PMC11733773DOI: 10.1098/rsbl.2024.0494Google 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 examines the link between habitat features and the behavior of feral horses, specifically female aggression, in response to social instability. The study suggests that habitat characteristics influence how these horses react to social instability, with changes promoting aggressive behavior among females.

Objective and Methodology

  • The primary objective of this paper is to understand how habitat features influence the animal reactions to social instability.
  • Insights into these relationships can offer a deeper understanding of evolutionary drivers and the consequences of social behavior in animals.
  • The research methodology involved studying an island population of “free-ranging” feral horses.
  • These horses either naturally inhabited or were forced into three different types of habitats as part of management-induced experiments on social stability.

Key Findings

  • The researchers found a correlation between female group-changing behavior, an indicator of social instability, and aggressiveness of other females.
  • This correlation was prominent only when habitat characteristics were considered.

Further Analysis

  • The researchers found no significant relationship between female group-changing behavior and the initiation of aggression or their ranks in the dominance hierarchies.
  • Similarly, the stability of female dominance hierarchies was found to be unaltered by group-changing behavior.
  • This indicates that a female horse’s position in a social structure and her aggressiveness are not necessarily determined by her propensity to change social groups.

Implications

  • The study suggests the complex reactions that animals have to social instability, which are greatly influenced by their surroundings.
  • Such findings shed light on the evolutionary factors that drive social behavior in animals and may help to mitigate any inadvertent effects of management practices.

Cite This Article

APA
Nuñez CMV, Adelman JS. (2025). Mean mares? Habitat features influence female aggression in response to social instability in the feral horse (Equus caballus). Biol Lett, 21(1), 20240494. https://doi.org/10.1098/rsbl.2024.0494

Publication

Biology letters
ISSN: 1744-957X
NlmUniqueID: 101247722
Country: England
Language: English
Volume: 21
Issue: 1
Pages: 20240494
PII: 20240494

Researcher Affiliations

Nuñez, Cassandra M V
  • Department of Biological Sciences, The University of Memphis, Memphis, TN, USA.
Adelman, James S
  • Department of Biological Sciences, The University of Memphis, Memphis, TN, USA.

MeSH Terms

  • Animals
  • Female
  • Aggression
  • Horses / physiology
  • Horses / psychology
  • Ecosystem
  • Social Dominance
  • Behavior, Animal / physiology
  • Social Behavior

Grant Funding

  • Association for American University Women (Research Publication Grant in Engineering, Medicine and Science, 2023-24)
  • University of Memphis (College of Arts and Sciences Faculty Research Grant, 2021)
  • University of Memphis (College of Arts and Sciences Faculty Research Grant, 2021)
  • Association for American University Women (Research Publication Grant in Engineering, Medicine and Science, 2023-24)

Conflict of Interest Statement

We declare we have no competing interests.

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