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Home / Equine Research Bank / Front Vet Sci / Horse vision through two lenses: Tinbergen’s Four Ques...
Frontiers in veterinary science2025; 12; 1647911; doi: 10.3389/fvets.2025.1647911

Horse vision through two lenses: Tinbergen’s Four Questions and the Five Domains.

Abstract: To improve human-horse interactions and reduce the risk of injury, it is essential to adopt an equi-centric perspective that prioritizes how horses perceive their environment. This review focuses on the equine visual system, both because it is the most studied of the horse's senses and because misunderstandings about how horses see can lead to unsafe or unsustainable handling. By applying two complementary frameworks, namely Tinbergen's Four Questions and the Five Domains model, we examine equine vision from both a biological and a welfare-oriented perspective. We explore the anatomical and functional features of the horse's eye, the development and evolution of visual capacities, and how these relate to behavior, performance and welfare, while also challenging common myths. Horses possess visual adaptations that enable them to perceive fine details, detect color, and see in dim light conditions. However, their evolutionary history as a prey species has shaped them to be highly sensitive to unfamiliar shapes and movements which we also need to be aware of. Ultimately, a deeper understanding of how horses process visual information can help correct misunderstandings, guide safer management practices, and support more ethical and effective care.
Copyright © 2025 Roth and McGreevy.
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Publication Date: 2025-08-14 PubMed ID: 40895790PubMed Central: PMC12392641DOI: 10.3389/fvets.2025.1647911Google Scholar: Lookup
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  • Journal Article
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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.

Overview

  • This research article examines how horses perceive their environment through their vision, using two analytical frameworks to better understand equine eyesight and its implications for behavior, welfare, and human-horse interactions.

Introduction to the Research

  • The article emphasizes the importance of adopting an “equi-centric” perspective, which means viewing the world from the horse’s point of view to improve safety and welfare in human-horse relationships.
  • The focus is on the equine visual system because:
    • It is the most studied of the horse’s sensory systems.
    • There are prevalent misunderstandings about how horses see that can lead to unsafe or inappropriate handling.

Analytical Frameworks Used

  • Tinbergen’s Four Questions:
    • A biological framework that addresses animal behavior by exploring:
      • Function (adaptation) – Why a trait or behavior exists;
      • Phylogeny (evolution) – How the trait evolved over time;
      • Mechanism (causation) – How the trait works physiologically;
      • Ontogeny (development) – How the trait develops in the individual.
    • This framework helps explain the evolutionary and developmental aspects of horse vision and its biological purpose.
  • The Five Domains Model:
    • A welfare-oriented framework used to assess an animal’s overall wellbeing, focusing on:
      • Nutrition, environment, health, behavior, and mental state.
    • This model shifts the focus from biological facts alone to include practical welfare outcomes and ethical considerations in how horses are managed.

Equine Visual System: Anatomical and Functional Features

  • Horses have specific eye structures that:
    • Enable perception of fine visual details.
    • Allow color discrimination—horses can see some colors, contradicting the myth that they only see in black and white.
    • Provide good vision in low light conditions, which is an evolutionary adaptation to crepuscular activity (dawn and dusk).
  • Despite these strengths, horses’ vision has limitations shaped by their evolutionary ecology as prey animals:
    • Highly sensitive to unfamiliar shapes and movements, triggering flight or startle responses.
    • Wide field of view but with visual blind spots directly in front and behind their heads.

Behavioral Implications of Visual Capacities

  • How horses process visual information influences:
    • Their safety responses to novel or surprising stimuli.
    • Performance in tasks requiring visual discrimination.
    • Stress and anxiety levels, which impact overall welfare.
  • The article challenges common myths regarding horse vision, such as the idea that horses see only in black and white or that they cannot see objects directly in front of them.

Applying Insights to Welfare and Management

  • A deeper understanding of equine vision can:
    • Correct misperceptions that may lead to unsafe handling practices.
    • Inform safer ways to approach, manage, and design environments for horses.
    • Support ethical care by acknowledging how horses experience their surroundings.
  • Knowledge gained from the two frameworks leads to improved welfare through practices tailored to the horse’s perceptual world.

Conclusion

  • This review integrates biological and welfare perspectives to give a comprehensive understanding of horse vision.
  • By recognizing how horses see the world, handlers and caretakers can improve communication, reduce risk, and promote more humane treatment.

Cite This Article

APA
Roth LSV, McGreevy P. (2025). Horse vision through two lenses: Tinbergen’s Four Questions and the Five Domains. Front Vet Sci, 12, 1647911. https://doi.org/10.3389/fvets.2025.1647911

Publication

Frontiers in veterinary science
ISSN: 2297-1769
NlmUniqueID: 101666658
Country: Switzerland
Language: English
Volume: 12
Pages: 1647911
PII: 1647911

Researcher Affiliations

Roth, Lina S V
  • IFM Biology, Linköping University, Linköping, Sweden.
McGreevy, Paul
  • Faculty of Science, Sydney School of Veterinary Science, University of Sydney, Sydney, NSW, Australia.

Conflict of Interest Statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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