Listening to the Cicada Chorus in the Plato Academy: soundscape research

Anastasia Georgaki

Résumé | Plan | Texte | Bibliographie | Notes | Citation | Auteur | a | A

Résumés   

Index   

Plan   

Introduction

ΕἰςτέττιγαΜακαρίζομένσε, τέττιξ,
ὅτιδενδρέωνἐπ΄ἄκρωνὀλίγηνδρόσονπεπωκώς,
βασιλεὺςὅπως, ἀείδειs (Ανακρέων)1

1At the beginning of my research on the decodification of the cicada singing, I started with a strong interest not in entomology but in the application of bioacoustics in music- through the domain of zoomusicology2 - and the sonic interaction between musicians and the nature. During my research, I had never imagined that there could have been written so many books and articles about these strange insects: geography of the cicada, mythology of the cicada, allegories of the cicada, music of the cicada, tasting the cicadas, mathematics of the cicada and so on.
I have started my investigation on the cicadas by recording -during the last two years- their monotonous singing from the first days of the summer till the end of September in order to decodify the changing rhythm and the variations of the chorusing which dominates the Greek soundscape(especially during July and August). Through the evaluation of my recordings in different places of Greece and a brief review of the bibliography on tettiggology I have concluded that the acoustic behavior of the cicada depends on which place you are, which time of the day, which time of the summer and how close you are in the source of the cicada. In some cases when you approach they stop immediately. Sometimes they sing in chorus and at once they stop all together for some minutes and then they restart.
Thus, I have decided to focus my research on the cicada singing at one place and I have chosen to do it at one of the most neglected areas in Athens: the archeological park of the Academy of Plato! I thought of my choice as being a tribute to the excellent Platonic dialogue on the cicada in “Phaedrus” (one of my first inspirations for this research3 ). The other reason that motivated me to start this soundscape research of the Archaeological Park at the Academy of Plato is that cicadas incessant singing during the hot daylight hours has been a constant and ubiquitous contributor to the local ambiance for millennia.

2Iannis Xenakis was frequently speaking about the cicada’s sound mass as an inspiring source for the creation of his stochastic sound synthesis4: “collisions of hail or rain with hard surfaces, murmuring of pine- forests, the song of cicadas in a summer field, “political crowds of dozens or hundreds of thousands of people’’. (Xenakis, 1992)
After many visits to the Gymnasium of the park, I tried to record the soundscape of the landscape related to the life cycle and the metamorphosis of the cicada in order to make a mapping of the their acoustic behavior from the beginning till the end of the summer (which indicates the beginning and the end of their short life!).
How and when the first cicada starts to sing? Which is the rhythm of the first singing? How it triggers other cicada to sing with him in order to attract the females?
Which is the sound of their nuptial ceremony? How do they start to feel the end of the summer and of their life? By a decreasing rhythm, frequency or amplitude? Or maybe by a decrease of all of those parameters?

ΗχέταΤέττιξ: The diachronic value of the cicada singing in the Greek landscape

3Let's start our presentation by a brief journey from the Ancient Greek to the Modern Greek poetry and literature in order to reveal the diachronic value of the cicada song in this land.5

4Tettigology has its roots in ancient civilization from Ancient China to Ancient Greece. More precisely, the cicada have so many and varied appearances in Greek culture: in literature, in the visual arts, in folklore but also in scientific writing, philosophy and religion. The ancient tettix (cicada) is one of the most inspirational insects for philosophers, poets and musicians of Ancient Greece. From the famous myth of Esope about the lazy singing cicadas (sic) and the working ants which has survived and is being taught in the schools till our days and the myth of Tithonus and Dawn (Ηώ)6 about the search for eternal youth, several myths have survived on the cicadas in the Greek and Roman literature.
The earliest explicit reference on the cicada singing, comes from Homer in the Illiad with the adjective leirios (like the flower 'lily') where Homer describes the 'shrilling voices' of the elder men, likened to Cicada song 'lily-like', after their city has been besieged7. Hesiodos reference8 underlines the advent of the summer by the first loud cicada song (ηχέτατέττιξ) and Anacreon creates a precious ode on the wonderful singing of the Tettix under the effect of dew (like the effect of the wine).9
Another interesting reference on the musicality of the cicadas comes from the myth of Eunomos an accomplished cithara player and singer, who has been assisted by a cicada during a music competition when one of the strings on his instrument snapped. The cicada climbed on his instrument and substituted its voice for the missing fifth string, enabling him to win. (Γεωργάκη, 2003)

5Apart from the mythology and the literature sources we have also the proofs of archaeologists who discovered coinage at Mycenae in the 19th century10. A thousand years later, Thucydides and later Plato write about the Cicada, which indicates, that both Mycenaeans and Athenians, were influenced by the life-cycle of the Cicada.11
The most inspirational story about the cicadas which has many allegoric interpretations about the immortality and resurrection of the souls, is discussed in Phaedrus, a dialogue authored by Plato: Socrates and Phaedrus, his student of rhetoric, engage in thoughtful repartee in an earthy setting by a lush riverbank-which nowadays is situated at Aghia Photeini-in the shade of a tree occupied by a chorus of cicadas.12 The Cicadas chirp and watch to see whether their music lulls humans to laziness or whether the humans can resist their sweet song. According to the dialogue Cicadas were originally humans who, in ancient times, allowed the first Muses to enchant them into singing and dancing so long that they stopped eating and sleeping and actually died without noticing it. The Muses rewarded them with the gift of never needing food or sleep, but to sing from birth to death. The task of the Cicadas is to watch the humans in order to report to the Muses who honors and who doesn’t.13 (Ferrari, 1987)
Τhe cicada song from the philosophical reference of Plato in Phaedrus about the reincarnation of the humans in cicadas and the immortality of soul14 to the excellent poem of Anacreon regarding the magical singing of cicada for the hedonistic part of life, brings us closer to understand how instructive and precious was the cicada singing for Ancient Greeks.
In the contemporary Attic landscape the cicada still sing and the poems of ancient Greeks find their continuity in the poems of J. Ritsos15, O.Elytis , G. Seferis, and other who exalt the summer hedonistic soundscape which is dominated by the chorusing of the cicadas.

On Cicada Singing scientific decodification16

6But it is clear that the ancient Greeks were not listening with the same ear as we do: for them, the song of the cicadas in a different soundscape, as this of Aghia Foteini described in Plato’s Phaedrus, could be a carrier of memory and a message somehow telling to people: "wake up-raise ... ".
How do we listen in our days to the cicadas? Which is the message carried by their insisting and monotone singing in chorus?
With the advent of science and technology we are invited to decodify the monotone singing of the cicadas in a different way. In order to deepen our understanding about cicadas we have gone through the secrets of entomology and we have noticed how the science has advanced (especially the last 60 years if we take into account various articles). The science of entomology has tried to solve the mystery of the cicada17 singing in different areas, as we have 2.500 species and at least 2.000 different calling songs. The researchers claim that the last decades it became evident, that the song patterns of singing cicadas are very specific and enable them to detect a presence of most species in a habitat without seeing and collecting them, just by recording and analyzing their acoustic emissions. In addition to this, one can recognize the hidden, morphologically inconspicuous species by analyzing and comparing their songs. (Boulard, 1995, p. 723)

7According to recent researches males produce a loud acoustic signal that is used to guide females towards them. The calling songs are frequently complex with changes in rhythm, amplitude modulation and, in many species, frequency modulation. A song that has many variations which deal with the physiology (specie), the temperature and the period of the summer. The sound communication of cicada is unidirectional and through that the males indicate their localization, identity and availability. Some species emit a regular succession of pulses and other have a slow pattern to their song, produced by the coordinated nervous excitation of three functional groups of muscles18. The cicada produces its characteristic loud tone by converting the energy of an extremely fast contracting muscle to sound energy, using both a mechanical and acoustic (Helmholtz) resonator. (Bennet-Clark, 1998, pp. 36-39)
Cicada songs appear to the human ear as being of great variety19. The function of the song is to assemble the local population of a cicada species (males and females) into a small group. (Sueur & Aubin, 2002, pp. 126-136) In Greece about 6 different species of cicadas have been detected. One of this species Cicada orni Linnaeus20 is one of the common cicadas throughout the Mediterranean area, being very familiar for the striking calling songs produced by males during summertime. It is distributed from the Iberian Peninsula in Western Europe to Greece and Turkey and some countries in the near East (as well as around the Black Sea). (Pinto-Juma, Simoes, Seabra, & Quartau, 2005, pp. 81-94) This cicada is known to occur in closed high shrubland and woodland, more commonly occurring in olive trees, pine trees, oak trees, and also eucalyptus and vineyards (Simues, et al., 2000, pp. 437-440). Concerning the acoustic communication of the cicada orni recent researches reveal that the song is produced by males which can sing continuously from a single site for hours, sometimes chorusing with other males. Let's investigate if in our case -where the evidences indicate the specie cicada orni-we have similar acoustic components.
Many cicadas have two components of song. This normally consists of a continuous component (i.e. a continuous phrase) and a broken component (separate phrases). The broken component may be divided into a set of repeated phrases. Other species have different broken components in their song (as in the example below). It can either be simple and repetitive (monotonous or alternating short phrase, long phrase etc) or syncopated (i.e. a more complex rhythm). (Sueur & Aubin, 2002)

Cicada mapping at the Academy of Plato

8After this analysis on the myth and the science of the cicada singing, it is time to present our project which is based on a soundscape research of the cicadas at the Academy of Plato (and most precisely at the Gymnasium area) from mid-July till the end of September in order to design the soundscape changes of the landscape in a virtual application (soundplayer).
The Academy of Plato21 today bears a strikingly different relationship to its immediate surroundings from that it enjoyed in antiquity. Today it is a 20 hectare oasis of green parkland. Walking to this area which today looks abandoned by the state despite its glamorous name, we can remark many problems in accessibility, management use of land and infrastructure.

Fig. 1. The area of Gymnasium (academy of Plato)

9Having the plan of the gymnasium area we have done different recordings which show the sonic activity of the cicadas during the month of July, August and September through four different angles, and we will present it¨
Α) in the Google earth map and
Β) in a virtual soundplayer program (which will show the activity of the cicadas depending on the season). The purpose of this application is to give an approximate description of the life-cycle of the cicada soundscape as a tribute to the platonic myth.

Methodology

10We have started the recordings in mid-July 2013, once a week, in the afternoon, in order to describe the acoustic activity of the cicadas at the Gymnasium area of the academy of Plato. Recordings were taken between 17:00 and 19:00 with temperatures ranging from 26 to 38°C. Most of the recordings were carried out using a Zoom recorder22 (at frequency ranges of 20~22,000 and 20~20,000 Hz, respectively, and at a sampling frequency of 44.1 kHz). We have also taken in account in which trees was happening the cicada solo or chorus singing (oak, olive, etc.) and their antiphonies.
The microphone was placed at a distance of at least 50 cm from the calling insect or at the angle of the rectangle (Gymnasium) at a distance about 2 meters from the trees in order to take the sound activity of the chorus. Our first concern was to identify different types of emitted songs of the cicadas and changes depending on the variations of temperature and the month in order to create a mapping of their acoustic behavior. While there is no direct correlation between habitat and the type of song produced, some general trends can be found. Before these can be defined the calling song types need to be delineated in terms of duration, frequency, tone, rhythm and complexity.
In the following paragraph, through a sound analysis with the software sonic visualizer23 we present the:
a) The main pattern (phrase) of the singing cicada (echeme24–interecheme) and their rhythm25. The definition of echeme is composed of groups of pulses and the duration of the interval between them (interecheme interval).

Fig. 2.  Oscillogram of one cicada (15/8/2013, 18:15, 34C)

Fig. 3.  Spectrogram of one cicada (15/8/2013, 18; 15, 34C)

11This signal can be described in the time domain as having echemes of 0.07 ± 0.04s (average ± standard deviation) in duration separated by intervals of 0.13 ± 0.07 s. (fig.2) It is made up of a regular repetition of echemes, which are composed of a variable number of groups of pulses. Moreover, the mean frequency was 5211 ± 100 Hz26. The spectrogram showed also a bandwidth (at -20 dB) of 7233 ± 700 Hz (fig.3)
b) Cicadas in Chorus (parameters of phasing, frequencies, amplitudes)
The next figures present the waveform and spectral analysis of a cicada chorus a hot afternoon in August 2013.

Fig. 4. Oscillogram of the cicada chorus (21/8/2013, 19:00, 28C)

Fig. 5. Spectrogram of the cicadas chorus ((21/8/2013, 19:00, 28C)

12At the second exemple, the analysis of the cicada chorus singing, can see that the pulses are not distinct as before (oscillogram) and that the mean frequency in the spectral analysis is 4.694Hz ±200 Hz with a bandwidth (at -20 dB) of 7233 ± 800 Hz
After this sample analysis of the patterns of the cicada (solo and chorus) at the Academy of Plato we have created an application in sound player where we have distributed the cicada song (according to the period from the 25/7 till the 25/9 in order to describe their acoustic behavior during summer), the degree of their chorusing and synchronization and give a virtual mapping of the Plato’s academy sound Utopia.

Further research

13Our main concern is to measure further the activity of the cicada in order to have the environmental feedback for the creation of an electroacoustic music event which will take place during the International Joint conference ICMC/SMC201427 at the Academy of Plato.
Our second concern is to create an interactive sound installation “Academic cicadas” where the actual cicada will interact with the electronic granular cicadas created by the software Cosmosf28 according to the Xenakian model. We will thus invite the audience to reinvent their eternal symbolic states of cicada through millennia: Metamorphosis, Rebirth, Self-expression and collaboration and …always on time.

Conclusions

14In this paper we have put the fundaments for a discrete soundscape research on the cicada activity at the archeological site of the Gymnasium of the Academy of Plato. We have sketched the acoustic behavior of the cicada through an allegoric link of Plato’s writings to the modern scientific results. Our main concern is to create an artistic soundbridge between the present and the past and create a future sound installation for September 2014 which will approach the platonic myth from a different acoustical view: “The Muses rewarded them with the gift of never needing food or sleep, but to sing from birth to death. The task of the Cicadas is to watch humans to report who honors the Muses and who does not.”29

15And don't forget: Cicadas only sing after they have done their last skin shed!

Ι would like to thank very much my assistant and collaborator Fotis Moschos who has helped me on the recordings and the technical aspects and the sound artist Dr. Sinan Bokesoy for his precious help on the sound player application.

Bibliographie   

Notes   

Citation   

Auteur   

Quelques mots à propos de :  Anastasia Georgaki