Animals Make Music: a Look at Non-Human Musical Expression

Multimodal Technologies and Interaction

Review Animals Make Music: A Look at Non-Human Musical Expression

Reinhard Gupﬁnger * and Martin Kaltenbrunner

Institute of Media Studies, University of Art and Design Linz, 4020 Linz, Austria; [email protected] * Correspondence: reinhard.gupﬁ[email protected]

Received: 20 April 2018; Accepted: 28 August 2018; Published: 2 September 2018

Abstract: The use of musical instruments and interfaces that involve animals in the interaction process is an emerging, yet not widespread practice. The projects that have been implemented in this unusual field are raising questions concerning ethical principles, animal-centered design processes, and the possible benefits and risks for the animals involved. Animal–Computer Interaction is a novel field of research that offers a framework (ACI manifesto) for implementing interactive technology for animals. Based on this framework, we have examined several projects focusing on the interplay between animals and music technology in order to arrive at a better understanding of animal-based musical projects. Building on this, we will discuss how the implementation of new musical instruments and interfaces could provide new opportunities for improving the quality of life for grey parrots living in captivity.

Keywords: ACI; animal music; animal-centered design; metamusic

1. Introduction The number of physical products and software applications developed speciﬁcally for animals and the commercial interest in technological mediators for human–animal interactions is growing [1–4]. In addition to the physical and graphical interaction design aspects of such technology, sound and music can also play an important role in the design process [5]. Despite the increasing amount of hardware and software for animals, there are only a few studies devoted to the use of audio technologies to enrich the living environment of animals in captivity [6–8]. In 2016, a research project was started by the authors of this paper in collaboration with the artist group alien productions and the zoologists and animal keepers of ARGE Papageienschutz. The principal goal of this project is to design and develop musical instruments and interfaces for a group of grey parrots held in captivity at an animal shelter near Vienna. This research is based on an ongoing art project named metamusic [9], which was initiated in 2012 by alien productions. Adopting an artistic approach, the collective has been investigating how grey parrots react to musical stimuli, exploring whether they can become an intrinsic part of interactive sound installations, and assessing whether they are capable of producing “parrot music” (new music that does not have to sound like music to human ears) by themselves. The project aims to generate artistic output for humans while improving the quality of life for grey parrots in captivity with musical instruments and interfaces. Recent research in the ﬁeld of cognitive biology has focused on the role of animals listening to human music as a concept of enrichment [10–13]. Since most of the music is selected by humans, this can lead to anthropomorphic biases. Therefore, the music should be attuned to the animals’ auditory skills. Studies have shown that non-human species also have musical skills [14–16] and display entrainment to auditory stimuli [17,18]. Animal species such as grey parrots, cockatoos, elephants, primates, pigeons, and carps have been found to be able to discriminate between different

Multimodal Technologies and Interact. 2018, 2, 51; doi:10.3390/mti2030051 www.mdpi.com/journal/mti Multimodal Technologies and Interact. 2018, 2, 51 2 of 14 composers or different genres, prefer music to silence, or move in rhythmic synchronicity to the musical beat [Multimodal10,14,17 Technol.–19]. Interact. 2018, 2, x FOR PEER REVIEW 2 of 14 According to further studies, some parrot species such as grey parrots and cockatoos have musical skillscomposers and a natural or different feeling genres, for rhythm prefer [17 music,18]. Greyto sile parrots,nce, or move for example, in rhythmic can synchronicity repeat musical to patternsthe musical beat [10,14,17–19]. and have the ability to reproduce sounds [15,20]. In this respect, it appears appropriate to work with According to further studies, some parrot species such as grey parrots and cockatoos have grey parrots in the context of animal-based music. musical skills and a natural feeling for rhythm [17,18]. Grey parrots, for example, can repeat musical Inpatterns 2011, and Clara have Mancini the ability in herto reproduce “Animal–Computer sounds [15,20]. Interaction In this respect, (ACI): it appears A Manifesto” appropriate proposed to the keystoneswork with grey for ACIparrots as in a the field context of research. of animal-based ACI researchmusic. aims to understand the interaction between animalsIn 2011, Clara and Mancini the computing in her “Animal–Computer technology [21], Interaction and is therefore (ACI): A a Manifesto” significant proposed step toward the an ethicalkeystones implementation for ACI as of a suchfield of technologies. research. ACI In rese thisarch manifesto, aims to understand Mancini discussed the interaction ethical between principles, guidelines,animals and and methodologiesthe computing technology for the design, [21], and analysis, is therefore and evaluation a significant of step ACI toward systems. an ethical To the best of ourimplementation knowledge, there of such is no technologies. comprehensive In this summary manifesto, and Mancini analysis discussed of projects ethical that involve principles, animals interactingguidelines, with and music methodologies instruments for and the design, interfaces. analysis We, thereforeand evaluation have of examined ACI systems. different To the approachesbest of our knowledge, there is no comprehensive summary and analysis of projects that involve animals and technologies in diverse fields from a musical interface designer’s perspective. This paper gives an interacting with music instruments and interfaces. We therefore have examined different overview of current technologies and important developments in the context of musical instruments approaches and technologies in diverse fields from a musical interface designer’s perspective. This that includepaper gives animals an overview in the musicof current and technologies sound-generating and important process, developments with a focus in on the the context creative of and artisticmusical outcomes instruments for both that animals include and animals humans. in the We music are interestedand sound-generating in gaining aprocess, better understandingwith a focus of the actualon the role creative of the and animals artistic interacting outcomes for with both such animals technologies. and humans. This We paper are interested attempts toin determinegaining a the factorsbetter that understanding could lead to of a the suitable actual design role of approachthe animals and interacting its ethical with implementation. such technologies. This paper attempts to determine the factors that could lead to a suitable design approach and its ethical 2. Culturalimplementation. Context

Musical2. Cultural instruments Context and interfaces that involve animals as musical agents can be found in different ﬁelds such as New Interfaces for Musical Expression (NIME), contemporary art installations, Musical instruments and interfaces that involve animals as musical agents can be found in animal cognition experiments, and ACI. Some of the earliest examples of conjectural musical different fields such as New Interfaces for Musical Expression (NIME), contemporary art instruments that (ab)use animals as sound generators can be found between the 16th and 19th centuries installations, animal cognition experiments, and ACI. Some of the earliest examples of conjectural undermusical the names instruments of the thatCat (ab)use Organ oranimals the Pig as sound Organ generators([22], Figure can 1be). found Both arebetween speculative, the 16th and piano-like 19th instrumentscenturies in under which the cats names or pigs of the are Cat placed Organ inside or the orPig attached Organ ([22], to the Figure instrument. 1). Both are When speculative, the keys are pressed,piano-like thus poking instruments the pig in orwhich pinching cats or the pigs tail are of pl theaced cat, inside the animalor attached cries to out the in instrument. pain and generatesWhen a pitchedthe sound.keys are Since pressed, both thus instruments poking the are pig based or pinching on inﬂicting the tail painof the upon cat, the animals, animal suchcries bizarreout in pain musical instrumentsand generates have nevera pitched been sound. built Since out of both ethical instruments and animal are based welfare on concerns.inflicting pain However, upon animals, these ideas providesuch evidence bizarre musical of an earlyinstruments interest have in humansnever been making built out music of ethical involving and animal animals, welfare in thisconcerns. case, as a structuralHowever, part these of the ideas musical provide instrument evidence itself. of an In early general, interest live in animals humans are making not usually music involving a constitutive animals, in this case, as a structural part of the musical instrument itself. In general, live animals are part of musical instruments, and there are not many examples in which such instruments have actually not usually a constitutive part of musical instruments, and there are not many examples in which been put into practice. such instruments have actually been put into practice.

Figure 1. Pig Organ, cover illustration for the piece of sheet music “La Piganino” [22]. Figure 1. Pig Organ, cover illustration for the piece of sheet music “La Piganino” [22].

Multimodal Technologies and Interact. 2018, 2, 51 3 of 14

The idea of animals becoming anthropomorphic musicians playing traditional acoustic instruments is much more common in the literature. Well-known fairy tales such as The Town Musicians of Bremen have popularized this concept. Since the middle of the 20th century, this particular configuration has often been restaged in a circus environment, where, in general, various species including primates were capable of performing various musical tasks through conditioning [23]. A related topic within the field of Human–Computer Interaction (HCI) is the design and use of new technologies for musical expression and artistic performance. Researchers and artists are developing new musical instruments and interfaces with the aim of understanding and influencing new forms of artistic expression, usability, and playability. The introduction and development of new technologies in this field also opens up new possibilities to include animals in the music-generating process. The projects we could find from this community are mostly combinations of a computer vision system tracking the animals, and a sound-generating system, which is controlled by the animals’ movements. A common setup in this field is fish-based interfaces [24–30]. The video tracking system observes the fish in the aquarium, and the sounds are generated or processed by the generally random movements of the fish [24]. The output of such fish-based musical interfaces can be manifold and creative, but since the fish are separated from the audio feedback, they lack an animal-centered design approach. Thus, in some of the projects, all of the plants, stones, and other aquarium furniture have been removed to provide a better camera view, which leads to the discussion of potential negative impacts on the living environment of the fish themselves. Another extensive field in which live animals are used in installations and projects is the contemporary art world. Various projects such as Harness by Robert Wechsler [31] or from here to ear by Céleste Boursier-Mougenot [32] focus on the relationship between animals and humans, and how animals can become the author or co-author of artworks or the creative process. Some artists such as Céleste Boursier-Mougenot deal with the musicality of animals by building installations that involve animals creating sonic environments. Birds, which are known for their musical talents [14,15], often play an important role in such art installations. In the field of animal cognition, test setups, for example with touchscreens, are sometimes used in experiments to provide an insight into the animals’ musicality or musical preferences [1]. However, these test devices are less attractive for musical interface design, because they generally do not focus on a playful design. However, their results, such as evidence of the entrainment of animals to music stimuli [17,18], have great significance for our study. These kinds of test devices have enabled scientists to gather evidence that animal species have auditory skills and musical talents, and examine how these skills work [15,16]. ACI aims at gaining a better understanding of how animals interact with technology, and thus some ACI employs technology as a mediator between different species, including humans. Even though ACI is growing fast, the potential opportunities for acoustic enrichment in the context of ACI technology have received little attention.

3. Musical Animal–Machine Interaction Based on the more active or passive role that animals can play in the interaction process with musical instruments and interfaces, we shall now discuss and analyze some projects focusing on the interaction between animals and music technology that we have identified as relevant to ACI. The analysis and classification of these projects provides a source of data that could potentially lead to further contributions in this field, and theoretical improvements in an animal-centered design process. In the following, we shall define four categories, which are generally based on the degree of musical agency of the individual species involved: Animal Movement as Control Source; Animals as Unconscious Performers; Animals as Trained Musicians; and Animals as Voluntary Musicians. Loosely related to the overall evolutionary stage, these categories are based on the musical understanding and the related physical and cognitive abilities of the individual species, which range from a complete lack of any auditory perception and expression to highly developed musical abilities and vocal Multimodal Technologies and Interact. 2018, 2, 51 4 of 14 expression. We intend to implement and extend the findings from the last category (Animals as Multimodal Technol. Interact. 2018, 2, x FOR PEER REVIEW 4 of 14 Voluntary Musicians) in our ongoing project to develop and design musical instruments and interfaces for greyabilities parrots. and vocal expression. We intend to implement and extend the findings from the last category (Animals as Voluntary Musicians) in our ongoing project to develop and design musical 3.1. Animalinstruments Movement and interfaces as Control for Source grey parrots. The first category of musical interfaces generally involves lower life forms such as bacteria or 3.1. Animal Movement as Control Source other simple animal species such as worms. These animals either completely lack any auditory sensory capabilitiesThe or first acoustic category expression, of musical orinterfaces are completely generally isolatedinvolves lower from perceivinglife forms such any as musical bacteria stimuli.or Thus,other in such simple a configuration, animal species these such animals as worms. only These play animals a passive either role, completely since they lack are unableany auditory to interact sensory capabilities or acoustic expression, or are completely isolated from perceiving any musical with input devices in the sound generation process, and only serve as nearly aleatory control sources. stimuli. Thus, in such a configuration, these animals only play a passive role, since they are unable to A typicalinteract example with input of suchdevices a musicalin the sound instrument, generation which process, in and this only case serve is controlled as nearly aleatory by live control worms, is the Dinsources. Datin A Duderotypical exampleproject developedof such a musical by Peter instrument, Blasser. which As the in wormsthis case wriggle is controlled around by live metallic contactworms, pins, is their the Din movements Datin Dudero modify project the developed circuits inside by Peter the Blasse synthr. and As the produce worms different wriggle soundsaround [33]. The experimentalmetallic contact design pins, their of the movements instrument modify appears the circuits to be suitedinside the to thesynth limited and produce physical different abilities of the wormssounds and [33]. basically The experimental integrates design their of bodies the instrument into the appears musical to circuitry be suited itself. to theIt limited remains physical unclear if the wormsabilities are of perceivingthe worms and the basically low-voltage integrates signals their though bodies theirinto the bodies musical and circuitry are capable itself. ofIt remains sensing any musicalunclear result if the at all.worms are perceiving the low-voltage signals though their bodies and are capable of sensing any musical result at all. Many of the musical examples we have found use a video tracking system to observe various Many of the musical examples we have found use a video tracking system to observe various animals and create sounds based on the overall movements of these animals. The most common animals and create sounds based on the overall movements of these animals. The most common speciesspecies used used in thesein these systems systems are are fish fish in in an an aquarium.aquarium. Since Since the the mid-2000 mid-2000s,s, this thisidea idea has been has been exploredexplored in different in different fields fields with with various various fish fish species.species. For For example, example, TheThe Accessible Accessible Aquarium Aquarium is a is a long-timelong-time project project of the of Georgia the Georgia Institute Institute of Technology of Technology in Atlanta in Atlanta that that is based is based on theon fieldthe field of informal of learninginformal environments. learning environments. It attempts toIt attempts make aquaria, to make zoos, aquaria, and sciencezoos, and centers science more centers accessible more for visitorsaccessible through for interaction visitors through and sonification,interaction and and soni thusfication, enhance and thethusvisitors’ enhance learningthe visitors’ experience learning [25]. The Accessibleexperience Aquarium [25]. Theenvironment Accessible Aquarium allows visitors environment to mimic allows the animals’ visitors movements to mimic the by usinganimals’ tangible objectsmovements to tell when by using a new tangible fish enters objects the to viewingtell when range,a new fish what enters kind the of viewing fish it is, range, and inwhat what kind direction of fish it is, and in what direction it’s moving; or add sounds or melodies to a specific aquarium fish. it’s moving; or add sounds or melodies to a specific aquarium fish. Sonifications corresponding to the Sonifications corresponding to the visitors’ movements can be paired with real-time animal-based visitors’ movements can be paired with real-time animal-based sonifications produced by the existing sonifications produced by the existing system to generate a musical composition of the visitors and systemthe to fish generate [26]. a musical composition of the visitors and the fish [26]. OtherOther fish-based fish-based projects projects such such as FuXi as FuXi[24 ],[24],Submersed Submersed Songs Songs[27 ],[27],Quintetto Quintetto([28 ([28],], Figure Figure2), 2),Musica sull’AcquaMusica[ 29sull’Acqua], and Sonification [29], and Sonification of Fish Movement of Fish Movement [30] take [30] a take more a artisticmore artistic approach. approach. Here, Here, fish are employedfish are as musicalemployed instruments as musical and instruments interfaces forand soundinterfaces installations for sound or musicalinstallations performances. or musical Even thoughperformances. all of the projects Even though mentioned all of abovethe projects use a me videontioned tracking above system, use a video they tracking differ from system, each they other in the waydiffer in from which each sound other isin mappedthe way in to which the fishes’ sound movementis mapped to and the whatfishes’ kind movement of sound and waswhat generated. kind Althoughof sound it has was been generated. shown thatAlthough some it fish has species been sh suchown asthat carp some can fish discriminate species such between as carp differentcan discriminate between different styles of music [34], and gurnard also have audio communication styles of music [34], and gurnard also have audio communication skills [35], these particular abilities skills [35], these particular abilities have not been investigated within the fish-based projects found have not been investigated within the fish-based projects found in this field. in this field.

Figure 2. Fish-based instrument Quintetto by Quiet ensemble 2009 [19]. Figure 2. Fish-based instrument Quintetto by Quiet ensemble 2009 [19].

Multimodal Technol. Interact. 2018, 2, x FOR PEER REVIEW 5 of 14 Multimodal Technologies and Interact. 2018, 2, 51 5 of 14 3.2. Animals as Unconscious Performers

3.2.This Animals section as Unconsciousdeals with Performersprojects that involve animals directly touching or triggering the interfaces, instruments, or sensors, and also involves species that have a developed hearing capability.This Nevertheless, section deals these with species projects lack that a general involve cognitive animals directlyunderstanding touching of the or triggeringcausality of the theirinterfaces, actions instruments,in relation to or the sensors, musical and results, also involves and are species therefore that unconscious have a developed musical hearing performers. capability. TheNevertheless, Intelligent MIDI these speciesSequencing lack with a general Hamster cognitive Control understanding project by Levy of the Lorenzo causality was of their a musical actions in instrumentrelation to that the musicalgenerated results, sounds and based are therefore on the unconsciousmovements musicalof six hamsters. performers. Each The hamsterIntelligent was MIDI placedSequencing inside witha narrow Hamster single Control trackproject where bythey Levy could Lorenzo only move was ain musical a lateral instrument direction. Based that generated on the effectivesounds range based of on a thedistance movements sensor ofand six the hamsters. typical length Each hamster of a hamster, was placed Lorenzo inside decided a narrow to build single 36-inchtrack wheretracks. theyThis couldallowed only the move hamsters in a lateral to walk, direction. sit up, Basedand turn on thearound effective while range still ofremaining a distance withinsensor sight and of the the typical distance length sensor of a hamster,[36]. The Lorenzo sounds decided generated to build depended 36-inch on tracks. the distance This allowed of the the hamsterhamsters from to the walk, sensor. sit up, The and hamsters turn around had whileno free still ch remainingoice to interact within with sight the of instrument, the distance and sensor they [36 ]. hadThe only sounds limited generated space to dependedmove within on the the instrument distance of tracks. the hamster It is unclear from thehow sensor. long the The hamsters hamsters had had to nostay free in the choice instrument. to interact with the instrument, and they had only limited space to move within the instrumentRobert Wechsler tracks. Itadopted is unclear a different how long approach the hamsters in his hadHarness to stay project in the [31]. instrument. He combined a mouse cage, includingRobert Wechsler a mouse adopted wheel, awith different a music approach box situated in his Harness outsideproject of the [ 31cage.]. He When combined the mouse a mouse exercisedcage, including on the wheel, a mouse it powered wheel, withthe music a music box, box and situated thus produced outside ofthe the sounds cage. stored When within the mouse it. Basedexercised on our on work the wheel,with grey it powered parrots the[37], music we assume box, and that thus it is produced a good approach the sounds for storedutilizing within a well-establishedit. Based on our device work for with pet greyenvironments. parrots [37 ],Ho wewever, assume positioning that it is the a good music approach box outside for utilizing of the a cagewell-established and therefore deviceshielding for it pet from environments. direct audio However, feedbackpositioning in the cage theseems music disadvantageous, box outside of thesince cage it alsoand isolates therefore the shielding mouse from it from the direct musical audio result. feedback in the cage seems disadvantageous, since it also isolatesA well-known the mouse art from project the musicalis from here result. to ear ([32], Figure 3) by Céleste Boursier-Mougenot. Since 1999, heA well-knownhas been developing art project musical is from hereenvironments to ear ([32 ],and Figure installations3) by C é lestefor finches Boursier-Mougenot. in public exhibitions.Since 1999, The he installations has been developing combine musicala set of environmentstraditional musical and installations instruments—mainly for finches electric in public guitarsexhibitions. and drums—that The installations serve combineas a resting a set place of traditional for the finches musical and instruments—mainly produce sounds upon electric contact. guitars Theand public drums—that is invited serve to enter as a restingthe installation place for sp theace finches and mingle and produce with the sounds finches, upon whose contact. movements The public generateis invited a live to entermusical the piece. installation Each installation space and can mingle be considered with the finches, as a unique whose piece movements that is living generate and a ephemeral;live musical it is piece. determined Each installation by the given can variables be considered of the situation as a unique and piece linked that to is the living circumstances and ephemeral; of theit given is determined moment by[32]. the Influenced given variables by the of audien the situationce, the andfinches linked generate to the a circumstances random sound of collage the given thatmoment allows [32 for]. Influenced minimal bycompositional the audience, theprocedures finches generate and choreographies a random sound defined collage thatby allowsspatial for arrangements.minimal compositional This project procedures is currently and one choreographies of the most defined established by spatial instal arrangements.lations in the This field project of animal–humanis currently one sound of the installation. most established Since it installationshas been shown in the that field finches of animal–human have musical soundabilities installation. [14,16], it wouldSince it be has interesting been shown to provide that finches them have with musical musical abilities instruments [14,16], that it would are adapted be interesting to the physical to provide skillsthem of withthe finches. musical instruments that are adapted to the physical skills of the finches.

FigureFigure 3. From 3. From here here to to ear ear byby Celeste Celeste Boursier-MougenotBoursier-Mougenot [32 [32].].

Multimodal Technologies and Interact. 2018, 2, 51 6 of 14

3.3. Animals as Trained Musicians

InMultimodal this section, Technol. Interact. we shall2018, 2,look x FOR atPEER projects REVIEW in which animals become active music performers. 6 of 14 There are numerous entertaining videos circulating virally around the Internet showing animals playing3.3. musicalAnimals as instruments. Trained Musicians. On video-sharing websites, there are numerous videos of dogs [38] and cats [39] playingIn this section, the piano, we shall trained look sealsat projects playing in which toy wind animals instruments become active [40], music and hens performers. playing toy instrumentsThere are [41 numerous]. entertaining videos circulating virally around the Internet showing animals Inplaying 2014, musical the zookeepers instruments. of the On Smithsonian’s video-sharing Nationalwebsites, Zoothere in are Washington numerous D.C.videos provided of dogs their[38] zoo animalsand with cats [39] some playing musical the instruments piano, trained [42 seals]. For playing example, toy wind they equippedinstruments their [40], otters and hens with playing a keyboard toy instruments [41]. and the orangutans with xylophones. The zoo’s intention was to enhance the well-being of the captive In 2014, the zookeepers of the Smithsonian’s National Zoo in Washington D.C. provided their animals, keep them active, and enrich their environment. They used traditional instruments designed zoo animals with some musical instruments [42]. For example, they equipped their otters with a for humanskeyboard such and asthe keyboards, orangutans with xylophones, xylophones. and The harmonicas, zoo’s intention which was obviouslyto enhance the was well-being a disadvantage of to somethe animalscaptive animals, with different keep them physiologies. active, and Thus, enrich it seemstheir environment. that the zookeepers They used did traditional not select the instrumentsinstruments based designed on the for skills humans of the such different as keyboa animalrds, xylophones, species. and harmonicas, which obviously Elephantswas a disadvantage are another to some species animals that with have different been given physiologies. musical Thus, instruments it seems that to enrich the zookeepers their lives in captivity.did not An select early the attempt instruments in this based regard on the was skills made of the by different the Thai animal Elephant species. Conversation Center with its Thai ElephantElephants Orchestra are another(Figure species4). Withthat have the intentionbeen given of musical creating instruments music for to humans, enrich their they lives designed in and builtcaptivity. massive An early musical attempt instruments in this regard adapted was made to theby the physical Thai Elephant abilities Conversation of the elephants. Center with In 1997, its Thai Elephant Orchestra (Figure 4). With the intention of creating music for humans, they designed the orchestra made its ﬁrst recording with ﬁve elephants, and subsequently released an audio CD in and built massive musical instruments adapted to the physical abilities of the elephants. In 1997, the 2001. From the very beginning, it was clear that elephants could, through endless repetition, be taught orchestra made its first recording with five elephants, and subsequently released an audio CD in to play2001. complex From the patterns very beginning, [43]. However, it was the clear creators that elephants decided thatcould, making through music endless should repetition, also be be fun for the elephants.taught to play Thus, complex the only patterns commands [43]. However, given to the the creators elephants decided were that to making start, stop, music and should occasionally also the numberbe fun for of timesthe elephants. to strike Thus, an instrument the only commands [43]. given to the elephants were to start, stop, and Theoccasionally instruments the number that of were times used to strike in thean instrument orchestra [43]. were mainly percussion instruments that the elephantsThe instruments could play that with were their used trunks. in the orchestra The percussion were mainly instruments percussion ranged instruments from that slit the drums, marimba-likeelephants instruments,could play with and their gongs trunks. to thunder The perc sheets,ussion bells, instruments and xylophones. ranged from Other slit instrumentsdrums, includedmarimba-like single-string instruments, instruments, and gongs harmonicas, to thunder and sh windeets, instruments.bells, and xylophones. The designs Other of instruments the instruments included single-string instruments, harmonicas, and wind instruments. The designs of the were adapted to the elephant’s anatomy and skills, and to the Thai cultural environment in which instruments were adapted to the elephant’s anatomy and skills, and to the Thai cultural the animals lived. The elephants often heard Thai music; therefore, the instruments were adapted environment in which the animals lived. The elephants often heard Thai music; therefore, the to soundinstruments similar were to Thai adapted instruments to sound [ 43similar]. It hasto Thai also instruments been observed [43]. thatIt has elephants also been observed can play that a steady beat [elephants44,45]. During can play the a coursesteady ofbeat the [44,45]. project, During it was th showne course that of the they project, could it make was shown music togetherthat they with othercould elephants make andmusic humans together [44 with]. The other combination elephants and of goodhumans instrument [44]. The designcombination and the of elephants’good musicalinstrument skills makes design this and project the elephants’ a promising musical approach. skills makes That thethis projectproject wasa promising founded approach. to raise money That for the Thaithe project Elephant was Conversation founded to raise Center money and forthus the Thai became Elephant a tourist Conversation attraction Center may and have thus had became a negative impacta tourist on the attraction animals. may For have instance, had a negative the project impact focused on the animals. on training For instance, elephants the to project play focused human-like musicon for training a human elephants audience. to play It wouldhuman-like have mu beensic interestingfor a human to audience. see what It would would havehave happenedbeen interesting to see what would have happened without any training, by just providing the elephants without any training, by just providing the elephants with musical instruments and seeing what kind with musical instruments and seeing what kind of musical output they created without the need to of musical output they created without the need to entertain a crowd of visitors. entertain a crowd of visitors.

Figure 4. The Thai Elephant Orchestra [43]. Figure 4. The Thai Elephant Orchestra [43].

Multimodal Technol. Interact. 2018, 2, x FOR PEER REVIEW 7 of 14

3.4.Multimodal Animals Technologies as Voluntary and Interact. Musicians2018, 2, 51 7 of 14 In the context of ACI, Fiona French [6] is currently investigating the potential of technological enrichment3.4. Animals for as Voluntarycaptive elephants. Musicians The design of the interactive toys for elephants also focuses on acoustic enrichment experiences. For example, one design concept was based on a harp-like instrumentIn the contextthat the ofelephants ACI, Fiona could French play with [6] is their currently trunks investigating [46]. In collaboration the potential with of animal technological welfare expertsenrichment and forelephant captive keepers, elephants. French The designutilized of sensors the interactive and switches toys for for elephants triggering also sounds. focuses The on soundsacoustic were enrichment adapted experiences. to the elephants’ For example, preferences, one design and concept60–70 Hz was frequencies based on a were harp-like used instrument to arouse thethat interest the elephants of the participating could play with elephant their Valli trunks [46]. [46 A]. further In collaboration relevant study with animalin ACI was welfare carried experts out withand elephantorangutans keepers, in zoos French by Pons utilized [7]. A sensors sound-ba andsed switches interactive for triggeringsystem was sounds. developed The soundsfor auditory were enrichment.adapted to the Instead elephants’ of providing preferences, orangutans and 60–70 with Hz human frequencies music, were the used system to arouse allowed the the interest animals of the to exploreparticipating different elephant typesValli of sounds[46]. A by further manipulating relevant study tangible in ACI object wass. carriedThe sound out withpreferences orangutans of the in orangutanszoos by Pons were [7]. A incorporated sound-based interactiveinto the design system pr wasocess, developed thus making for auditory it animal-centered. enrichment. Instead In our of opinion,providing the orangutans works of French with human and Pons music, could the be system seen allowedas best practices the animals in the to explorecontext differentof ACI, and types both of approachessounds by manipulating could be used tangible for the objects. development The sound of preferences musical instruments of the orangutans and interfaces were incorporated for other speciesinto the as design well. process, thus making it animal-centered. In our opinion, the works of French and Ponsmetamusic could be seenis a asproject best practicesby the artist in the group context alien of productions ACI, and both (Martin approaches Breindl, could Norbert be used Math, for and the Andreadevelopment Sodomka) of musical that was instruments produced and in interfacescooperation for otherwith a species group asof well. African grey parrots. Since 2012,metamusic the artistsis have a project been byworking the artist in groupclose collaalienboration productions with(Martin zoologists Breindl,, biologists, Norbert and Math, animal and Andreakeepers. Sodomka) that was produced in cooperation with a group of African grey parrots. Since 2012, the artistsThe initial have beenidea workingbehind the in closeproject collaboration was to deve withlop zoologists,interactive biologists,sound installations and animal for keepers. animals held Thein captivity initial idea in behindzoological the project gardens. was Much to develop remains interactive to be done sound to installations offer new forchallenges animals heldand diversionsin captivity to in the zoological zoo inhabitants. gardens. Muchmetamusic remains aims to to be build done electronic to offer new sound challenges installations and diversions to be used to bythe the zoo animals inhabitants. themselves.metamusic Usingaims a wide to build range electronic of sensors sound and installations tools, the animals to be used are able by the to animalsexplore andthemselves. play with Using sounds a wide and rangesonic ofmoods. sensors Based and on tools, the theadvice animals of their are ablezoologic to exploreal collaborators, and play withthey havesounds centered and sonic their moods. attention Based on on parrots, the advice which of theirhave zoologicalturned out collaborators, to be the ideal they animal have centered species becausetheir attention of their on nature. parrots, Although which have they turned are regarded out to be theas wild ideal animals animal specieswith complex because social of their flocking nature. Althoughbehavior, each they of are the regarded birds has as been wild animalsbred or at with least complex raised by social humans. ﬂocking behavior, each of the birds has beenThe bredmetamusic or at leastproject raised has byshown humans. that there is great potential for these kinds of open-sound environmentsThe metamusic and greyproject parrots. has shown In collaboration that there is with great the potential grey parrots, for these the kinds artists of open-soundhave been developingenvironments and and modifying grey parrots. mechanical In collaboration and electronic with the instruments grey parrots, and the artiststools that have can been be developingplayed by theand modifyingbirds themselves. mechanical Fine-tuned and electronic sensors instruments provide andinteractive tools that modulation can be played of the by thesounds. birds Nevertheless,themselves. Fine-tuned the musical sensors patterns provide and sonic interactive structures modulation generated of by the the sounds. parrots Nevertheless,are not meant the to soundmusical aesthetically patterns and meaningful sonic structures to human generated ears. The by theproject parrots also areintend not meantfor the toparrots sound communicate aesthetically withmeaningful each other to human by means ears. of Thetheir project own musical also intend output for created the parrots by their communicate personalized with instruments each other ([9], by Figuremeans 5). of their own musical output created by their personalized instruments ([9], Figure5).

Figure 5. metamusic, joystick device [37]. Figure 5. metamusic, joystick device [37].

Multimodal Technologies and Interact. 2018, 2, 51 8 of 14

4. Animal-Centered Musical Interaction Design In general, all of the projects presented above have strengths and weaknesses in terms of their concepts and implementations. There are already promising approaches to improve the quality of life for animals in captivity with the use of music and sounds. In some of the projects, the selection of animal species seems arbitrary and not related to the animals’ cognitive and physical skills. We have shown that some projects lack an animal-centered perspective, and many of the participating animals do not voluntarily intend to generate music by interacting with the provided interface or instrument. Additionally, many animals have been specifically trained or conditioned in order to perform predefined musical patterns. Some of the projects also raise questions regarding the design of interfaces and musical instruments, which were not explicitly adapted to the abilities and needs of the participating animals. The use of traditional musical instruments designed for humans may not be appropriate, and reveals a lack of an animal-centered design approach, as proposed in Mancini’s ACI manifesto [9]. In some cases, the animals had no choice between different musical instruments or interfaces. It is hard to imagine that more ambitious musical performances could be performed in these settings, and ethical principles are another consideration altogether. Another question that needs to be addressed is the meaning of sound and music to the animals. Although there are approaches to adapt the frequencies of the sounds [6,37,46] or the music to the personal preferences of the animals [1,7], there is no evidence that any species appreciated the acoustic stimuli. A number of studies in the field of biomusicology, for example [47–50], have found that animals prefer sounds and musical arrangements that are biologically relevant for them. This important point was not considered in the examples provided above, and it is therefore questionable if any of the approaches provided beneficial enrichment to the animals. Our work is focused on finding a framework that would fulfill the challenging tasks of implementing an animal-centered design process, generating an artistic output, and above all, helping to stimulate discussion about enriching the quality of life of grey parrots in captivity. In the next section, we shall look at the key points involved in the implementation of musical interfaces for animals.

4.1. Musical Capabilities The selection of an appropriate animal species for participation in the interaction process with musical instruments and interfaces is of essential importance. Based on expertise gathered from animal cognition [14], we have identiﬁed several animal species that have a particularly high degree of musicality, such as spontaneous entrainment, in comparison to others. Hoeschele’s list of species with vocal learning and entrainment abilities also shows those animal species that have been tested and shown to have musical skills. As Figure6 shows, vocal learning ability is generally a good indicator that the species has strong auditory skills. Entrainment in animals is unusual, and involves the ability to align their movements to a musical beat. This ability has been found in grey parrots, cockatoos, and elephants, and has thus disproved the claim that entrainment to music is unique to humans [17,18]. These animals are able to move synchronously to music. Therefore, it is reasonable to assume that these animals can also maintain a rhythm with a steady tempo, as the active music performers of the Thai Elephant Orchestra have demonstrated. The animals on the list have the best prerequisites for playing an active role in projects that involve musical instruments. The questions of whether these talented animals appreciate music and whether they like making music or not require further study. Finally, whether the music created by animals pleases people is secondary to an animal-centered approach, and as such, animal music need not sound like music to human ears. A further approach would be to select an animal species that is close to humans such as chimpanzees. It seems likely that they would share some human cognitive abilities [14], and thus would be interesting for further research. For example, orangutans, another related species, have shown interest in sound objects for individual auditory enrichment [7]. The Toronto Zoo Multimodal Technologies and Interact. 2018, 2, 51 9 of 14 conducted a study to determine the music preference of orangutans by using a participant-controlled, dichotomous-choice design. The orangutans were trained to indicate their music preference via touchscreen [1]. Furthermore, the orangutans of the Smithsonian’s National Zoo in Washington D.C. were equipped with xylophones, and it was reported that they showed interest in playing them [42]. Multimodal Technol. Interact. 2018, 2, x FOR PEER REVIEW 9 of 14

FigureFigure 6. 6.Vocal Vocal learning learning and and entrainment entrainment inin animals according to to Hoeschele Hoeschele [14]. [14 ].

4.2. PhysicalA further and Cognitive approach Abilities would be to select an animal species that is close to humans such as chimpanzees. It seems likely that they would share some human cognitive abilities [14], and thus wouldAnother be interesting crucial question for further concerns research. the developmentFor example, orangutans, of an appropriate another animal-centered related species, designhave approach,shown interest which concentratesin sound objects on the for speciﬁcindividual physical auditory and enrichment cognitive capabilities [7]. The Toronto of each Zoo species, conducted as well asa its study speciﬁc to needs.determine The the main music problem preference here isof toorangutans gather and by understandusing a participant-controlled, the animal feedback. Thisdichotomous-choice requires different design. techniques The or [2angutans], such as were a review trained of to the indica relevantte their literature music preference on the animal via species,touchscreen the observation [1]. Furthermore, of the animalsthe orangutans in their of living the Smithsonian’s environment, Na andtional the Zoo development in Washington of testingD.C. prototypeswere equipped [46]. The with design xylophones, process and of suchit was testing reported prototypes that they showed should alsointerest be basedin playing on the them results [42]. of cognitive science and animal behavior, as well as an analysis of the physical capabilities of the animal 4.2. Physical and Cognitive Abilities participants. The sounds and music that are used need to take the individual differences of the animals into account.Another Our crucial work question with grey concerns parrots the [37 developm] and French’sent of workan appropriate with elephants animal-centered [46] show design that it is alsoapproach, necessary which to adjust concentrates the pitches on the of thespecific audio physical frequencies and cognitive to make capabilities them better of perceptible each species, for as the animalwell species.as its specific needs. The main problem here is to gather and understand the animal feedback. This requires different techniques [2], such as a review of the relevant literature on the animal 4.3.species, Engagement the observation versus Training of the animals in their living environment, and the development of testing prototypes [46]. The design process of such testing prototypes should also be based on the results of With regard to the various projects presented above, there are several different approaches to cognitive science and animal behavior, as well as an analysis of the physical capabilities of the motivating the animal species that are involved in the installations. The scope ranges from imprinting animal participants. The sounds and music that are used need to take the individual differences of behaviors, intense training, and rewarding through food to setups in which the animals were free to the animals into account. Our work with grey parrots [37] and French’s work with elephants [46] interactshow withthat it the is instrumentsalso necessary and to wereadjust only the rewardedpitches of andthe motivatedaudio frequencies though to the make sounds them generated better byperceptible their actions. for Wethe animal believe species. that a setup that relies on the animals’ satisfaction to motivate them to make sounds with the musical instruments is suited for animal species such as elephants and grey parrots,4.3. Engagement which have versus been Training proven to have some form of musical skills. An engaging, playful sonic system may provide a self-training environment to improve the animals’ musical skills. The animals’ With regard to the various projects presented above, there are several different approaches to intrinsic motivation could be one of the keys to successfully implementing this kind of technology to motivating the animal species that are involved in the installations. The scope ranges from improveimprinting the well-being behaviors, intense of animals training, in captivity and reward [51,52ing]. through For example, food to French setups usesin which such the an animals approach in herwere work free withto interact elephants with [6the,46 ].instruments The elephants and arewere already only rewarded integrated and into motivated the design though process the by voluntarilysounds generated testing different by their sensorsactions. We for theirbelieve user that interfaces. a setup that In contrast,relies on the there animals’ are elephants satisfaction that to are trainedmotivate to play them musical to make instruments sounds with [43 the] or musical draw picturesinstruments under is suited the guidance for animal of trainers.species such A study as of fourelephants captive and Asian grey elephantsparrots, which at the have Melbourne been prov Zoo,en Australia,to have some examined form of painting musical by skills. elephants An in zoosengaging, [53], whichplayful issonic believed system to may be a provide form of a enrichment. self-training However, environment the to results improve indicated the animals’ that the elephantsmusical gainedskills. littleThe enrichmentanimals’ intrinsic from the motivati activityon of painting.could be one of the keys to successfully implementing this kind of technology to improve the well-being of animals in captivity [51,52]. For example, French uses such an approach in her work with elephants [6,46]. The elephants are already integrated into the design process by voluntarily testing different sensors for their user interfaces. In contrast, there are elephants that are trained to play musical instruments [43] or draw pictures under the guidance of trainers. A study of four captive Asian elephants at the Melbourne Zoo, Australia, examined painting by elephants in zoos [53], which is believed to be a form of enrichment. However, the results indicated that the elephants gained little enrichment from the activity of painting.

Multimodal Technologies and Interact. 2018, 2, 51 10 of 14

Multimodal Technol. Interact. 2018, 2, x FOR PEER REVIEW 10 of 14 5. Future Work 5. Future Work Our further research aims to show that grey parrots in captivity can generate unique artistic outcomesOur with further musical research instruments aims to andshow interfaces that grey in pa playfulrrots in environments, captivity can generate in which unique grey parrots artistic can freelyoutcomes choose with which musical instrument instruments they want and interfaces to play or in interact playful with, environments, thereby adopting in which an grey active parrots role as a performer.can freely choose We believe which there instrument is a chance they towant foster to pl relationshipsay or interact between with, thereby grey parrotsadopting and an humansactive byrole opening as a performer. new creative We communicationbelieve there is a processes chance to basedfoster onrelationships sound and between music. grey The parrots project and could expandhumans the by horizon opening of ACInew researchcreative communication by developing musical processes instruments based on sound and interfaces and music. for The animals, project and couldcould also expand provide the further horizon contributions of ACI research to design by de conceptsveloping in musical other disciplines instruments such and as interfaces HCI or animal for behavior.animals, Therefore, and could wealso conducted provide further a series contributions of experiments to design with concepts a group in of other grey parrotsdisciplines at thesuchARGE as PapageienschutzHCI or animalanimal behavior. shelter Therefore, [37]. There, we conducted we tested a the series auditory of experiments skills and with preferences a group of of the grey grey parrots at the ARGE Papageienschutz animal shelter [37]. There, we tested the auditory skills and parrots as a group, while also identifying any individual characteristics. These tests were carried out in preferences of the grey parrots as a group, while also identifying any individual characteristics. cooperation with zoologists, and respected the ethical principles of the ACI manifesto [21]. However, These tests were carried out in cooperation with zoologists, and respected the ethical principles of a suitable methodology that allows the grey parrots to participate in the design process itself has yet to the ACI manifesto [21]. However, a suitable methodology that allows the grey parrots to participate be found. Our design intended to avoid any conditioning of the animals, and instead supported their in the design process itself has yet to be found. Our design intended to avoid any conditioning of the inherentanimals, capabilities and instead and supported needs. The their individuals inherent fromcapabilities our group and of needs. grey parrotsThe individuals generally from preferred our a loudnessgroup of and grey pitch parrots matching generally their preferred own communication a loudness and habits, pitch as matching well as generally their own faster communication rhythms [37 ]. habits,Based as on well the as musical generally skills faster and rhythms preferences [37]. of our group of grey parrots, we subsequently moved on to designBased aon series the ofmusical analog skills musical and instrumentspreferences of and our computer-controlled group of grey parrots, interfaces we subsequently that adapt to thesemoved capabilities. on to design We alsoa series incorporated of analog musical our observations instruments of and the computer-controlled grey parrots’ behaviors interfaces toward that and interactionsadapt to these with ourcapabilities. experimental We also musical incorporated interfaces. our We observations observed a generalof the grey curiosity parrots’ toward behaviors any new artifacttoward that and we interactions added to the with environment, our experimental leading mu tosical an interfaces. overall exploration We observed and a ageneral tendency curiosity toward tryingtoward to disassembleany new artifact the that whole we artifact.added to While the environment, we initially leading tried to to work an overall around exploration these behaviors, and a wetendency eventually toward decided trying to incorporate to disassemble these the interactions whole artifact. into theWhile fundamental we initially interaction tried to work design around of our musicalthese artifacts.behaviors, We we are eventually currently decided designing to newincorporate musical these instruments interactions that areinto based the fundamental on traditional designinteraction metaphors design such of our as stringmusical and artifacts. percussion We are instruments, currently designing or more new contemporary musical instruments designs such that as digitalare based turntables. on traditional Finally, wedesign are alsometaphors planning such to incorporateas string and the percussion animals’ highlyinstruments, developed or more vocal capabilitiescontemporary into andesigns acoustic such feedback as digital design. turntables. All of theseFinally, designs we are also also consider planning the to particular incorporate physical the interactionanimals’ patternshighly developed of grey parrots, vocal capabilities which are mostlyinto an performedacoustic feedback with the design. parrot All beak. of these So far, designs we have also consider the particular physical interaction patterns of grey parrots, which are mostly implemented two instruments, and according to our observations, the grey parrots playfully interacted performed with the parrot beak. So far, we have implemented two instruments, and according to with them. One of them, the disc jockey (DJ) instrument, is based on a foraging wheel for parrot our observations, the grey parrots playfully interacted with them. One of them, the disc jockey (DJ) enrichment, in which the birds have to spin a wheel to collect their treats. When a grey parrot spins instrument, is based on a foraging wheel for parrot enrichment, in which the birds have to spin a the wheel of the DJ instrument (Figure7), the parrot will not be rewarded with food but with sound. wheel to collect their treats. When a grey parrot spins the wheel of the DJ instrument (Figure 7), the Sinceparrot the will parrots not arebe rewarded already familiar with food with but this with form so ofund. interaction, Since the theyparrots should are already be able tofamiliar learn quicklywith howthis to form operate of interaction, the device tothey get should their reward. be able Into furtherlearn quickly experiments how to with operate the DJthe turntabledevice to instrument,get their wereward. want to In ﬁnd further out inexperiments more detail with whether the DJ differentturntable soundsinstrument, are perceivedwe want to as find a reward out in more or a positivedetail experiencewhether different by the grey sounds parrots. are perceived as a reward or a positive experience by the grey parrots.

Figure 7. metamusic, disc jockey (DJ) device [7]. Figure 7. metamusic, disc jockey (DJ) device [7].

Multimodal Technol. Technologies Interact. and Interact.2018, 2, 2018x FOR, 2 ,PEER 51 REVIEW 11 11 of 14

The second device is a collaborative instrument (Figure 8) in which a parrot plays “hand-in-hand”The second devicewith another is a collaborative parrot or a instrument person. It (Figureconsists8) of in a which tube with a parrot a spring plays reverb “hand-in-hand” installed withinside another that can parrot be triggered or a person. from both It consists sides by of pul a tubeling withon a arope. spring The reverb tube instrument installed inside is intended that can to stimulatebe triggered the frombirds’ both interest sides in by interacting pulling on and a rope. making The music tube instrumenttogether, since is intended grey parrots to stimulate usually live the inbirds’ long-term interest couple in interacting relationships. and making We are music also focusing together, on since designing grey parrots further usually experimental live in long-term musical instrumentscouple relationships. and carrying We are alsoout focusingdifferent on sonic designing experiments further experimental for use in musical art installations instruments and performances.carrying out different At the sonicsame experiments time, we are for giving use in artcareful installations consideration and performances. to whether the At themusical same instrumentstime, we are givingand interfaces careful considerationdeveloped have to whetherthe potent theial musical to improve instruments the quality and of interfaces life of grey developed parrots inhave captivity. the potential to improve the quality of life of grey parrots in captivity.

Figure 8. metamusic, tube device [8]. Figure 8. metamusic, tube device [8]. 6. Conclusions 6. Conclusions Our overview of recent musical instruments and interfaces that involve animals in the Our overview of recent musical instruments and interfaces that involve animals in the interaction interaction and music-generation process is novel, and highlights the costs and benefits of projects of and music-generation process is novel, and highlights the costs and benefits of projects of this kind. this kind. It provides insights into current technologies in this field and the musical talents of It provides insights into current technologies in this field and the musical talents of animals. Some of animals. Some of the participating animal species such as elephants and grey parrots have shown the participating animal species such as elephants and grey parrots have shown musical abilities and musical abilities and skills in musical performances. We have proposed a classification based on the skills in musical performances. We have proposed a classification based on the role that the animals role that the animals play as a collaborator in the musical environments and performances. Only the play as a collaborator in the musical environments and performances. Only the few projects presented few projects presented above in Section 3.4. Animals as Voluntary Musicians seem to be promising above in Section 3.4. Animals as Voluntary Musicians seem to be promising technological and musical technological and musical mediators between the animals themselves and between animals and mediators between the animals themselves and between animals and humans. Thus, they present humans. Thus, they present approaches to improve the quality of life of animals in captivity. approaches to improve the quality of life of animals in captivity. Based on our earlier work, we plan to continue with our practice-based research approach to Based on our earlier work, we plan to continue with our practice-based research approach to develop new musical instruments and interfaces for grey parrots living in captivity. Ultimately, we develop new musical instruments and interfaces for grey parrots living in captivity. Ultimately, hope to identify general cross-species design patterns for musical instruments from our research, we hope to identify general cross-species design patterns for musical instruments from our research, which may even become relevant to human-centered design aspects. which may even become relevant to human-centered design aspects. Funding: This project is supported by the Austrian Science Fund FWF through the Programme for Arts-based Funding: This project is supported by the Austrian Science Fund FWF through the Programme for Arts-based Research (PEEK AR 349-G24). Acknowledgments: We’d also like to thankthank our partnerspartners Martin Breindl, Andrea Sodomka and Norbert Math from alien productions as well as the animalanimal keepers from ARGEARGE PapageienschutzPapageienschutz..

ConflictsConﬂicts of Interest: The authors declare nono conﬂictconflict ofof interest.interest.

Multimodal Technologies and Interact. 2018, 2, 51 12 of 14

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