title: Enduring voice recognition in bonobos.
abstract: Long-term social recognition is vital for species with complex social networks, where familiar individuals can encounter one another after long periods of separation. For non-human primates who live in dense forest environments, visual access to one another is often limited, and recognition of social partners over distances largely depends on vocal communication. Vocal recognition after years of separation has never been reported in any great ape species, despite their complex societies and advanced social intelligence. Here we show that bonobos, Pan paniscus, demonstrate reliable vocal recognition of social partners, even if they have been separated for five years. We experimentally tested bonobos' responses to the calls of previous group members that had been transferred between captive groups. Despite long separations, subjects responded more intensely to familiar voices than to calls from unknown individuals - the first experimental evidence that bonobos can identify individuals utilising vocalisations even years after their last encounter. Our study also suggests that bonobos may cease to discriminate between familiar and unfamiliar individuals after a period of eight years, indicating that voice representations or interest could be limited in time in this species.
authors.affiliation: Université de Lyon/Saint-Etienne, Equipe Neuro-Ethologie Sensorielle, ENES/Neuro-PSI, CNRS UMR 9197, Saint-Etienne, France.|University of St. Andrews, School of Psychology &Neuroscience, St. Andrews, Scotland, UK.
authors.forename: Sumir
authors.initials: S
authors.lastname: Keenan
authors.affiliation: Université de Lyon/Saint-Etienne, Equipe Neuro-Ethologie Sensorielle, ENES/Neuro-PSI, CNRS UMR 9197, Saint-Etienne, France.|Department of Psychology, Hunter College, CUNY, New York, USA.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Mathevon
authors.affiliation: Royal Zoological Society of Antwerp, Centre for Research and Conservation, Antwerp, Belgium.
authors.forename: Jeroen Mg
authors.initials: JM
authors.lastname: Stevens
authors.affiliation: Vallée des Singes Zoological Park, Romagne, France.
authors.forename: Jean Pascal
authors.initials: JP
authors.lastname: Guéry
authors.affiliation: University of St. Andrews, School of Psychology &Neuroscience, St. Andrews, Scotland, UK.|Université de Neuchâtel, Department of Comparative Cognition, Neuchâtel, Switzerland.
authors.forename: Klaus
authors.initials: K
authors.lastname: Zuberbühler
authors.affiliation: Université de Lyon/Saint-Etienne, Equipe Neuro-Ethologie Sensorielle, ENES/Neuro-PSI, CNRS UMR 9197, Saint-Etienne, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Levréro
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D005260:Female; D008297:Male; D019974:Pan paniscus; D021641:Recognition, Psychology; D012919:Social Behavior; D013997:Time Factors; D014831:Voice