title: Domestic horses send signals to humans when they face with an unsolvable task.
abstract: 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.
authors.affiliation: Graduate School of Intercultural Studies, Kobe University, 1-2-1 Tsurukabuto, Nada-ku, Kobe, 657-8501, Japan. r_monamie@pony.kobe.u-ac.jp.
authors.forename: Monamie
authors.identifier: 0000-0002-4813-939X
authors.initials: M
authors.lastname: Ringhofer
authors.affiliation: Graduate School of Intercultural Studies, Kobe University, 1-2-1 Tsurukabuto, Nada-ku, Kobe, 657-8501, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D003142:Communication; D003463:Cues; D005260:Female; D006736:Horses / Q000523:psychology*; D006801:Humans; D008297:Male; D011340:Problem Solving; D012919:Social Behavior; D014741:Video Recording; D014828:Vocalization, Animal
keywords: Communication; Horses; Knowledge state; Social cognition