Melody in Human–Cat Communication (Meowsic) Origins, Past, Present and Future Schötz, Susanne; Eklund, Robert; van de Weijer, Joost

Published in: Proceedings of FONETIK 2016

2016

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Citation for published version (APA): Schötz, S., Eklund, R., & van de Weijer, J. (2016). Melody in Human–Cat Communication (Meowsic): Origins, Past, Present and Future. In Proceedings of FONETIK 2016 (pp. 19–24). (TMH-QPSR; Vol. 57, No. 1). https://www.ida.liu.se/~robek28/pdf/Schotz_Eklund_VanDeWeijer_2016_Meowsic_Fonetik2016.pdf

Total number of authors: 3

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LUND UNIVERSITY

PO Box 117 221 00 Lund +46 46-222 00 00 Melody in Human–Cat Communication (Meowsic): Origins, Past, Present and Future 1 2 3 Susanne Schötz, Robert Eklund, Joost van de Weijer 1Department of Clinical Sciences, Division of Logopedics, Phoniatrics, and Audiology / Humanities Laboratory, Lund University, Sweden 2 Department of Culture and Communication, Division of Language and Culture, Linköping University, Sweden 3 Center for Languages and Literature, Division of General Linguistics and Phonetics / Humanities Laboratory, Lund University, Sweden [email protected], [email protected], [email protected]

Abstract Eklund had the opportunity to record the impressive cheetah Caine (see Web The recently funded, five-year, project Resources), Eklund, Peters and Duthie Melody in Human–Cat Communication (2010) presented a study on purring in (Meowsic) has received vast media a big cheetah and a small domestic cat attention, both nationally and around at Fonetik 2010, Lund University. They the world. In this paper we summarize showed that purring F0 was roughly the how our activities got started, our same in both species (~30 Hz), despite published results so far, the present the 25-fold difference in size between situation and how we envision our the animals. They also examined the planned, future research, including differences between egressive and some of the core hypotheses to be ingressive phases in both species, and addressed by the project. later studies have shown that these are Introduction subject to large individual variation in both frequency, amplitude and duration. The recently funded, five-year, project Inspired by the paper and the Melody in Human–Cat Communication talk, Schötz went home and recorded (Meowsic) has received vast media the purring of her own cat Vincent. attention, both nationally and around Moreover, when she a few months the world. In this paper we summarize later became caretaker of the three how our activities got started, our young cats Donna, Rocky and published results so far, the present Turbo she recorded them as well, situation and how we envision our contacted Eklund and that way initiated planned, future research, including collaboration. some of the core hypotheses to be The Past (2011–2015) addressed by the project members. Since the Swedish national Fonetik The aforementioned collaboration, and conferences have been at the core when the addition of Joost van de Weijer to it comes to dissemination of our results the mix, has resulted in a plethora of within this field, we deemed it studies, both of purring and of other appropriate to summarize and present felid vocalisations. These are briefly our findings at the 2016 meeting. described in the following.

The Origins (2010) More purring (2011)

Following activities as a volunteer at At Fonetik 2011, KTH, in Stockholm, the Dell Cheetah Centre in Parys, South Schötz and Eklund (2011) presented a Africa (see Web Resources), where paper on purring in four domestic cats. The results added to the previously Human perception of cat vocalisations reported characteristics of egressive and Schötz and van de Weijer (2014a/b) ingressive phases. (Incidentally, Eklund examined human listeners’ ability to and colleagues presented two papers on classify domestic cat vocalisations lion roars at the same conference: (meows) recorded during feeding time Eklund et al. 2011; Ananthakrishnan (food related meows) and while waiting et al., 2011.) to visit a veterinarian (vet related meows). A pitch analysis showed Beyond purring (2012–2015) a tendency for food related meows to In 2012 – while/although Eklund once have rising F0 contours, while vet again presented a paper on purring, related meows tended to have falling this times in cheetahs (Eklund et al. F0 contours. Thirty listeners judged 2012a) – both Eklund and Schötz, twelve meows (six of each context). independently, moved beyond purring, Classification accuracy was signi- and presented papers on vocalisations ficantly above chance, and listeners from a wider perspective in domestic who reported previous experience with cats (Schötz, 2012) and agonistic cats performed significantly better than vocalisations in cheetahs (Eklund et al. inexperienced listeners. Moreover, the 2012b; also see Web Resources). two food related meows with the During the period 2012–2015, highest classification accuracy showed Schötz and her colleague van de clear rising F0 contours, while clear Weijer established themselves as the falling F0 contours characterized the authorities par excellence on domestic two vet related meows that received the cat vocalisations, from different highest classification accuracy. perspectives, described below. Additionally, Schötz (2014) conducted a pilot study where 36 Affiliative cat vocalisations human listeners classified 28 cat vocalisations into seven emotion In 2012, Schötz collected 538 affiliative categories. Classification accuracy and vocalisations from three domestic cats. between-listener agreement varied Based on auditive analysis, the considerably between vocalisations. vocalisations were categorized into five The vocalisations were subdivided into types and analysed for duration and F0. categories based on the emotions Within each type, duration was similar perceived by most listeners and across the three cats, but F0 compared in an acoustic analysis. measurements (mean, minimum and Preliminary results suggest that cats maximum) were not, due to the large vary their intonation to signal different type number of intonation patterns used emotions, and that humans perceive in each type. them based on cues used to signal emotion in human speech. Surprisingly, Prey-directed cat vocalisations the chirr (trill) vocalisation used for affiliative greetings was often Schötz (2013) collected 257 prey- misjudged as anger. directed vocalisations from three cats. Agonistic cat vocalisations The sounds were subdivided into the types chatter, chirp, tweet and tweedle, Schötz (2015) recorded 468 agonistic and analysed for duration and F0. cat vocalisations as one cat was Variation was found within and introduced to her home with three between these types as well as within resident cats. Six vocalisation types and between the three cats in both were identified: growl, howl, howl- duration and F0. growl, hiss, spit and snarl. Numerous other merged vocalisations and order to learn more about how cats use combinations were also observed. prosodic variation when interacting An acoustic analysis showed with humans. Specifically, we will try differences within and between all to answer three main research types in duration, F0 and spectral centre questions: of gravity. 1. What are the most common types of During the same period, Eklund cat vocalisations and how do they and Peters (2013) presented a study of differ prosodically? purring in cheetahs of different ages, as well as a tongue-in-cheek paper on “Cat 2. Which types are used in different contexts or situations? Language” as described in a thesis from 1895 (Eklund, 2015). 3. How do human listeners perceive this prosodic variation? The Present (2015–2016) Our hypotheses are: In January 2015 the authors wrote an application for a project grant 1. Cats “semi-consciously” use distinct with the aim to combine the findings prosodic patterns (intonation, of our earlier studies further, with intensity, length and voice quality) focus on prosody in human–cat vocal in different contexts to adjust, interaction. The project received emphasize or alter the meaning of a funding from the Marcus and Amalia vocalisation

Wallenberg foundation (MAW) in 2. Similar types of prosodic variation December 2015, and will start officially are used by different/most cats. in September 2016. The project objectives are described below. 3. Experienced human listeners are able to interpret this variation. The Future (2016–) A searchable and annotated corpus with The purpose of the project is to study high quality sound and video recordings the communication between humans of at least 30 domestic cats from two and domestic cats. Specifically, we will regions of Sweden (East central, South) investigate how prosody, including will be collected. We will record the voice, melody (intonation) and cats together with their human speaking style – in human speech as caretakers in their homes in everyday well as in cat vocalisations – influence interactive situations, e.g. at feeding vocal communication. The project will time, when greeting a companion, carry out two major studies. during play, etc.

Study 1. Prosody in cat vocalisations Based on auditory and acoustic analyses of the cat vocalisations, we This study will build on existing will develop a typology of the prosodic theories of cat vocalisations. Previous variation of cat vocalisations. studies (e.g. Moelk, 1944; Ohala, 1984; Schötz & van de Weijer, 2014a/b, Study 2. Cat perception of (human) speech prosody Schötz, 2014) suggest that cats vary the intonation and other prosodic features As was shown by Burnham, Kitamura (voice quality, rhythm and duration) in and Vollmer-Conna (2002), pet- different contexts and when signalling directed speech shares many of different emotions and/or messages. the characteristics of infant-directed However, to our knowledge no larger speech. However, we do not know systematic acoustic study of the nature whether pets, like infants, are also more of this variation has been carried out. drawn to this kind of speech than to We will explore a number of features in speech that lacks these characteristics. In order to investigate this question is a prerequisite for dialectal variation: we will carry out a discrimination without learning, no dialects. experiment in which we expose cats to External collaboration audio samples of pet-directed and adult- directed speech – natural as well as The research team collaborates with resynthesized stimuli – and record their clinical veterinarians, including reactions to these samples. This Ann-Charlotte Sandberg (Landskrona experiment will serve two purposes: Smådjursklinik), and also with etho- First, we want to explore which logists, including Jennie Westander behavioral responses in cats may be (PhD in Ethology, head of Education used in an experimental setting. and Research at Kolmården Wildlife As preliminary candidates for such Park) and Elin Hirsch (PhD student in responses, we consider head (and eye) Applied Ethology, Swedish University turns, ear and body movements, and of Agricultural Sciences). exploring behaviour; Second, we want Moreover, we will collaborate with to investigate whether any of these some of the world’s leading experts on responses is suggestive of a preference animal communication and felid for either: a) pet-directed, or adult- vocalisations, including Dr. Gustav directed, speech; b) children’s or adult Peters, Professor Gisela Håkansson, and voices; c) familiar or unfamiliar voices. Professor Emeritus John Ohala. This To minimise the stress level of the means that we will be in very good cat participants, the experimental position to elucidate acoustic-phonetic sessions will be carried out in the cats’ aspects of cat vocalisations, relevant home environment. We will use a for communication between humans specially built mobile box (which is and cats. carefully cleaned after each session to Parallel projects remove any remaining scents) to provide a similar environment for all Outside Meowsic, the research team is cats, and the video recordings will be also active in three related projects that scored by two independent judges in most likely will prove of value. order to guarantee objectivity and First, in 2013 Eklund recorded reliability of the results. various cheetah vocalisations at the N/a’an ku sè Foundation in Namibia, as Inspiration: dialects in cats? part of project officially sanctioned by

Further inspiration concerning language the Namibian Government. Analyses learning comes from both ancient are under way and will be conducted in and recent sources. Already Aristotle collaboration with Dr. Florian Weise, observed that birds exhibited both Stuart Munro and Gustav Peters. vocal learning and dialectal variation Second, Eklund is collaborating (Zirin, 1980). Moreover, recently it was with Dr Andrew Kitchener and Georg discovered that the Norwegian fin Hantke at National Museums Scotland whales have at least six different in Edinburgh, where post mortems of dialects (Vester et al. 2016) – which all felid species are planned in order to does not come as a surprise since map larynx structures with reported the literature is replete with reports vocalisations in those species. of “dialects” in animal vocalisations. Third, Schötz and van de Weijer Thus, we hypothesize to find dialectal collaborate with Elin Hirsch and variation in domestic cats. Maria Andersson, Swedish University Another issue is to what extent – if of Agricultural Science and the Centre at all – vocal learning can be observed. for Feline Behaviour and Welfare in a This, as already Aristotle mentioned, multi-disciplinary study of prosody, behaviour and welfare in the domestic An acoustic analysis of lion cat. The plan is to develop a web based roars. II: Vocal tract charac- toolbox with descriptions and examples teristics. In: Quarterly Progress to be used by humans wanting to assess and Status Report TMH-QPSR, cat welfare and well-being. 51, Proceedings from Fonetik 2011, 8–10 June 2011, Royal Media attention Institute of Technology, University press releases are normally Stockholm, Sweden, 5–8. made only when results are beginning Annals of Improbable Research, to show up, but Lund University made May/June 2015, 21(3), Special an exception for our project, which issue “Cats (and Dogs)”, 6–8. proved a correct decision: media Burnham, D., Kitamura, C., Vollmer- attention has been enormous, and the Conna, U. (2002). What’s New, authors find it hard to even keep track Pussycat? On Talking to Babies of where Meowsic is reported. and Animals. Science, 296, 1435. We have now (June 2016) done over Eklund, R., Peters, G. (2013). thirty interviews which have resulted A comparative acoustic analysis of in over 100 articles in magazines, purring in juvenile, subadult and newspapers and websites. adult cheetahs. In: Robert Eklund Just to mention a few, we have (ed.), Proceedings of Fonetik 2013, been covered by National Geographic, the XXVIth Swedish Phonetics The Washington Post, The Guardian, Conference, Studies in Language BBC 5 Live, The Telegraph, Daily and Culture, no. 21, 12–13 June Mail, as well as Swedish radio, TV 2013, Linköping University, and press, Norwegian radio and online Linköping, Sweden, 25–28. all over the world, including Chile, Eklund, R. (2015). Grimaldi’s China and Vietnam. “Discovery of the Cat Language”: However, we take special pride in A theory in need of revival (or being covered in a special issue “Cats perhaps not?) In: Proceedings (and Dogs)” of Annals of Improbable from Fonetik 2015, Working Research (i.e. the people behind the Papers 55/2015, 8–10 June 2015, Ig Nobel Prizes) where three of our Lund University, Lund, Sweden, papers are mentioned, and Eklund’s 27–30. purring website is also referred to (see Eklund, R., Peters, G., Duthie, E. D. References and Web resources). (2010). An acoustic analysis of purring in the cheetah (Acinonyx Acknowledgements jubatus) and in the domestic cat (Felis catus). In: Proceedings of The authors gratefully acknowledge Fonetik 2010, Lund University, support from Marcus and Amalia 2–4 June 2010, Lund, Sweden, Wallenbergs Minnesfond and Lund 17–22. University Humanities Lab. We are also Eklund, R., Peters, G., very grateful to all our consultants for Ananthakrishnan, G., Mabiza, E. their support and participation in the (2011). An acoustic analysis of project. We would also like to thank all lion roars. I: Data collection our cat informants. and spectrogram and waveform

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