Melody Matters: An Acoustic Study of Domestic Cat Meows in Six Contexts and Four Mental States Susanne Schötz 1 , Joost van de Weijer 2 , Robert Eklund 3 1 Department of Logopedics, Phoniatrics and Audiology, Lund University, Sweden 2 Lund University Humanities Lab, Sweden 3 Department of Culture and Communication, Linköping University, Sweden Corresponding Author: Susanne Schötz Dept. of Logopedics, Phoniatrics, and Audiology, Lund University, SE-221 85 Lund, Sweden Email address: susanne.schotz@med.lu.se Abstract This study investigates domestic cat meows in different contexts and mental states. Measures of fundamental frequency (f0) and duration as well as f0 contours of 780 meows from 40 cats were analysed. We found significant effects of recording context and of mental state on f0 and duration. Moreover, positive (e.g. affiliative) contexts and mental states tended to have rising f0 contours while meows produced in negative (e.g. stressed) contexts and mental states had predominantly falling f0 contours. Our results suggest that cats use biological codes and paralinguistic information to signal mental state. Introduction Acoustic cues to paralinguistic information like a human speaker’s physical and emotional state can be found in fundamental frequency (f0), intensity and duration (see e.g. Gangamohan, Kadiri, & Yegnanarayana, 2016). Some of these cues are related to so called biological codes, which can be observed in humans as well as nonhuman species. An example is that according to the ‘frequency code’ high f0 indicates smallness, submission, friendliness, and uncertainty, while low f0 signals largeness, dominance, aggressiveness, and certainty (Morton, 1977; Ohala, 1983; Gussenhoven, 2016). Animals are able to experience and express emotions (Bekoff, 2007, p. 42; Briefer, 2012), and as a consequence, it is reasonable to expect that their physical and mental state influences their vocalisations to include paralinguistic information found in f0 and duration. Domestic cats (Felis catus) are – next to dogs (Canis lupus familiaris) – the most common companion animals in the world. Over 600 million cats are said to live with humans worldwide (Saito, Shinozuka, Ito, & Hasegawa, 2019). Cats have developed an extensive, variable and complex vocal repertoire, probably best explained by their social organisation, their nocturnal activity and the long period of association between mother and young (Bradshaw, Casey, & Brown, 2012). Moreover, as a consequence of their interaction with human beings, cats have learned to vary and nuance their voices ever since they were domesticated, approximately 9500 years ago (Vigne, Guilaine, Debue, Haye, & Gérard, 2004). Proc. 2 nd Intl. Workshop on Vocal Interactivity in-and-between Humans, Animals and Robots (VIHAR), London, UK, 29-30 Aug 2019 29