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Home / Equine Research Bank / Sci Rep / Horses discriminate between facial expressions of conspecifi...
Scientific reports2016; 6; 38322; doi: 10.1038/srep38322

Horses discriminate between facial expressions of conspecifics.

Abstract: In humans, facial expressions are rich sources of social information and have an important role in regulating social interactions. However, the extent to which this is true in non-human animals, and particularly in non-primates, remains largely unknown. Therefore we tested whether domestic horses (Equus caballus) could discriminate between facial expressions of their conspecifics captured in different contexts, and whether viewing these expressions elicited functionally relevant reactions. Horses were more likely to approach photographic stimuli displaying facial expressions associated with positive attention and relaxation, and to avoid stimuli displaying an expression associated with aggression. Moreover, differing patterns of heart rate changes were observed in response to viewing the positive anticipation and agonistic facial expressions. These results indicate that horses spontaneously discriminate between photographs of unknown conspecifics portraying different facial expressions, showing appropriate behavioural and physiological responses. Thus horses, an animal far-removed from the primate lineage, also have the ability to use facial expressions as a means of gaining social information and potentially regulating social interactions.
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Publication Date: 2016-12-20 PubMed ID: 27995958PubMed Central: PMC5171796DOI: 10.1038/srep38322Google 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.

This research study examines whether horses can discriminate between different facial expressions of other horses and react appropriately. It found that horses not only successfully differentiate between expressions, but also display appropriate responses in behavior and heart rate.

Objective of the Research

  • The objective of the study was to explore whether domestic horses (Equus caballus) can distinguish between various facial expressions of their own species (conspecifics). This built on the understanding that in humans, facial expressions are a primary source of social information and play a pivotal role in social interactions. The study aimed to investigate to what extent this is also true for non-human animals, focusing specifically on non-primate species.

Methodology

  • Researchers tested the horses’ abilities to discriminate between different facial expressions by presenting them with photographic stimuli. The photographs represented various contexts including positive attention, relaxation, and aggression.
  • They monitored the horses’ behaviors, such as whether they approached or avoided the images, under these different stimuli. Additionally, they kept track of changes in the horses’ heart rates to record physiological responses.

Findings

  • The research study found that horses were more likely to approach images displaying facial expressions associated with positive attention and relaxation. They tended to avoid images depicting aggressive expressions.
  • There were also notably different patterns in heart rate changes when the horses were presented with photographs showing positive anticipation versus those showing agonistic or aggressive facial expressions.

Implications

  • These findings suggest that horses can spontaneously discriminate between different facial expressions portrayed in photographs of other horses, unknown to them, and respond appropriately both behaviorally and physiologically.
  • This indicates that horses, even though they are far removed from the primate lineage, also have the ability to use facial expressions for gathering social information and potentially regulating social interactions. It contributes to a broader understanding that the ability to interpret facial expressions is not limited to humans and primates, but may be more prevalent across the animal kingdom than previously thought.

Cite This Article

APA
Wathan J, Proops L, Grounds K, McComb K. (2016). Horses discriminate between facial expressions of conspecifics. Sci Rep, 6, 38322. https://doi.org/10.1038/srep38322

Publication

Scientific reports
ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 6
Pages: 38322
PII: 38322

Researcher Affiliations

Wathan, J
  • Mammal Vocal Communication and Cognition Research, School of Psychology, University of Sussex, UK.
Proops, L
  • Mammal Vocal Communication and Cognition Research, School of Psychology, University of Sussex, UK.
  • Centre for Comparative and Evolutionary Psychology, Department of Psychology, University of Portsmouth, UK.
Grounds, K
  • Mammal Vocal Communication and Cognition Research, School of Psychology, University of Sussex, UK.
McComb, K
  • Mammal Vocal Communication and Cognition Research, School of Psychology, University of Sussex, UK.

MeSH Terms

  • Aggression / physiology
  • Aggression / psychology
  • Animals
  • Attention / physiology
  • Facial Expression
  • Heart Rate / physiology
  • Horses / physiology
  • Horses / psychology
  • Humans
  • Photography

Grant Funding

  • BB/F016808/1 / Biotechnology and Biological Sciences Research Council

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