Domestic horses send signals to humans when they face with an unsolvable task
Some domestic animals are thought to be skilled at social communication with humans due to the process of domestication. Horses, being in close relationship with humans, similar to dogs, might be skilled at communication with humans. Previous studies have indicated that they are sensitive to bodily signals and the attentional state of humans; however, there are few studies that investigate communication with humans and responses to the knowledge state of humans. Our first question was whether and how horses send signals to their potentially helpful but ignorant caretakers in a problem-solving situation where a food item was hidden in a bucket that was accessible only to the caretakers. We then examined whether horses alter their behaviours on the basis of the caretakers’ knowledge of where the food was hidden. We found that horses communicated to their caretakers using visual and tactile signals. The signalling behaviour of the horses significantly increased in conditions where the caretakers had not seen the hiding of the food. These results suggest that horses alter their communicative behaviour towards humans in accordance with humans’ knowledge state.
KeywordsHorses Social cognition Communication Knowledge state
Special thanks to the students of the equestrian club in Kobe University. We are grateful to Fuki Maehara for her support in our study’s video analysis. We also thank Dr. Shigeto Dobata for his support in the study’s statistical analysis. The study was supported by grants from the Japan Society for the Promotion of Science (KAKENHI Nos. 26118509, 15H01619 and 15H05309 to Shinya Yamamoto).
Compliance with ethical standards
The experimental procedure for the horses was approved by the Institutional Animal Care and Use Committee (Permission number: 27-12-02) and carried out according to the Kobe University Animal Experimentation Regulation. All procedures adhered to the Japanese Act on the Welfare and Management of Animals.
Conflict of interest
We have no competing interests.
- Byrne RW, Whiten A (1989) Machiavellian intelligence: social expertise and the evolution of intellect in monkeys, apes, and humans. Oxford Science Publications, New YorkGoogle Scholar
- Feh C (2005) Relationships and communication in socially natural horse herds. In: Mills D, McDonnell S (eds) The domestic horse: the evolution, development and management of its behaviour. Cambridge University Press, Cambridge, pp 83–93Google Scholar
- Kaminski J, Bräuer J, Call J, Tomasello M (2009) Domestic dogs are sensitive to a human's perspective. Behaviour 146:979–998Google Scholar
- Kusunose R, Tanaka T, Satou S, Kondo S (1995) The repertoire of behaviour. In: Sato S, Kondo S, Tanaka T, Kusunose R (eds) Ethograms of farm animals. Asakura Shoten, Tokyo, pp 18–97 (in Japanese) Google Scholar
- Levine MA (2005) Domestication and early history of the horse. In: Mills D, McDonnell S (eds) The domestic horse: the evolution, development and management of its behaviour. Cambridge University Press, Cambridge, pp 5–22Google Scholar
- Nicol CJ (2005) Learning abilities in the horse. In: Mills D, McDonnell S (eds) The domestic horse: the evolution, development and management of its behaviour. Cambridge University Press, Cambridge, pp 169–183Google Scholar
- R Development Core Team (2005) R: a language and environment for statistical computing. R Foundation for Statistical Computing. Vienna. http://www.R-project.org