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Home / Equine Research Bank / PLoS One / Are horses capable of mirror self-recognition? A pilot study...
PloS one2017; 12(5); e0176717; doi: 10.1371/journal.pone.0176717

Are horses capable of mirror self-recognition? A pilot study.

Abstract: Mirror Self-Recognition (MSR) unveils complex cognitive, social and emotional skills and it has been found only in humans and few other species, such as great apes, dolphins, elephants and magpies. In this pilot study, we tested if horses show the capacity of MSR. Four subjects living socially under naturalistic conditions were selected for the experiment. We adopted the classical mark test, which consists in placing a coloured mark on an out-of-view body part, visible only through mirror inspection. If the animal considers the image as its own, it will use its reflection to detect the mark and will try to explore it. We enhanced the classical paradigm by introducing a double-check control. Only in the presence of the reflecting surface, animals performed tactile and olfactory exploration of the mirror and looked behind it. These behaviors suggest that subjects were trying to associate multiple sensory cues (visual, tactile and olfactory) to the image in the mirror. The lack of correspondence between the collected stimuli in front of the mirror and the response to the colored mark lead us to affirm that horses are able to perceive that the reflected image is incongruent when compared with the memorized information of a real horse. However, without replication of data, the self-directed behavior towards the colored marks showed by our horses cannot be sufficient per se to affirm that horses are capable of self-recognition.
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Publication Date: 2017-05-16 PubMed ID: 28510577PubMed Central: PMC5433687DOI: 10.1371/journal.pone.0176717Google 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 explores whether horses have mirror self-recognition (MSR) abilities, a cognitive skill found in few species, by using a mark test under naturalistic conditions. The results suggest horses may perceive incongruities between a reflected image and their information about a real horse, but self-recognition cannot be definitively confirmed without further data replication.

About the Research

The study focused on investigating the potential for MSR in horses. MSR is a cognitive skill that indicates an animal’s capacity to recognize its own reflection in a mirror. This ability presents complex cognitive, social, and emotional skills and has previously only been noted in humans and a few other species like elephants, dolphins, and magpies.

  • The researchers selected four horses that lived under naturalistic social conditions for their pilot study.
  • They applied the classical mark test, which implied placing a coloured mark on a body part of an animal that could only be seen through mirror inspection. If an animal perceives the image as its own, it will examine the mark via its reflection.
  • The researchers enhanced the traditional mark test by adding a ‘double-check’ control.

Key Findings and Interpretations

  • The horses only performed tactile and olfactory exploration of the mirror and looked behind it when a reflecting surface was present. This behaviour suggests that the horses tried to associate multiple sensory cues – visual, tactile, and olfactory – with the image in the mirror.
  • The collected data indicated a lack of correspondence between the horses’ stimuli in front of the mirror and the response to the coloured mark. From this, the researchers inferred that the horses could perceive that the reflected image was incongruent when compared with their memorized information of a real horse.

Limits of the Study

The researchers caution that, owing to the limitations of their pilot study, these findings should be interpreted with caution. They admitted that the self-directed behaviour towards the coloured marks displayed by the horses is not sufficient in itself to definitively assert that horses are capable of self-recognition. More data replication is needed for conclusive evidence of horses possessing MSR.

Cite This Article

APA
Baragli P, Demuru E, Scopa C, Palagi E. (2017). Are horses capable of mirror self-recognition? A pilot study. PLoS One, 12(5), e0176717. https://doi.org/10.1371/journal.pone.0176717

Publication

PloS one
ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 12
Issue: 5
Pages: e0176717
PII: e0176717

Researcher Affiliations

Baragli, Paolo
  • Dipartimento di Scienze Veterinarie, Università di Pisa, Pisa, Italy.
  • Museo di Storia Naturale, Università di Pisa, Calci, Italy.
Demuru, Elisa
  • Museo di Storia Naturale, Università di Pisa, Calci, Italy.
Scopa, Chiara
  • Dipartimento di Scienze Veterinarie, Università di Pisa, Pisa, Italy.
  • Museo di Storia Naturale, Università di Pisa, Calci, Italy.
Palagi, Elisabetta
  • Museo di Storia Naturale, Università di Pisa, Calci, Italy.
  • Unità di Primatologia Cognitiva, ISTC-CNR, Roma, Italy.

MeSH Terms

  • Animals
  • Behavior, Animal
  • Horses
  • Pilot Projects
  • Recognition, Psychology
  • Visual Perception

Conflict of Interest Statement

The authors have declared that no competing interests exist.

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