title: Wolf howling is mediated by relationship quality rather than underlying emotional stress.
abstract: While considerable research has addressed the function of animal vocalizations, the proximate mechanisms driving call production remain surprisingly unclear. Vocalizations may be driven by emotions and the physiological state evoked by changes in the social-ecological environment, or animals may have more control over their vocalizations, using them in flexible ways mediated by the animal's understanding of its surrounding social world. While both explanations are plausible and neither excludes the other, to date no study has attempted to experimentally investigate the influence of both emotional and cognitive factors on animal vocal usage. We aimed to disentangle the relative contribution of both mechanisms by examining howling in captive wolves. Using a separation experiment and by measuring cortisol levels, we specifically investigated whether howling is a physiological stress response to group fragmentation and whether it is driven by social factors, particularly relationship quality. Results showed that relationship quality between the howler and the leaving individual better predicted howling than did the current physiological state. Our findings shed important light on the degree to which animal vocal production can be considered as voluntary.
authors: Department of Evolutionary and Functional Biology, University of Parma, 43121 Parma, Italy; Wolf Science Centre, 2115 Ernstbrunn, Austria.
authors: Francesco
authors: F
authors: Mazzini
authors: Simon W
authors: SW
authors: Townsend
authors: Zsófia
authors: Z
authors: Virányi
authors: Friederike
authors: F
authors: Range
mesh_terms: D000819:Animal Communication; D000818:Animals; D004644:Emotions; D006854:Hydrocortisone / Q000032:analysis; D012463:Saliva / Q000737:chemistry; D013315:Stress, Psychological; D019596:Wolves / Q000502:physiology*
chemical_list: D006854:Hydrocortisone
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