While few studies have focused exclusively on the influence of sound on territory, it is now becoming apparent that every wild site I’ve recorded generates bioacoustic boundaries that define its territorial limits. So what exactly are the boundaries of these biophonies? From a set position, how far out do the acoustic characteristics of the biophony remain intact before they begin to shift? If indeed they do shift, what sonic components have changed?
Little by little, with more time in the field, I discovered that new pieces of the niche hypothesis puzzle began to fit, and I found evidence that it is possible to define animals’ geographical territory through an analysis of biophonic expression. When the thought of acoustically defined territory occurred to me, I set out to determine if there were ways to experience the phenomenon. The idea for acoustic mapping was inspired by a couple of groups performing aircraft noise studies. One, Harris, Miller, Miller, and Hanson, a Massachusetts acoustics firm headed by Nick Miller, had created an animated model for the National Park Service (NPS) at the Grand Canyon, showing how single-and twin-engine aircraft noise penetrated the surrounding landscape as the planes passed over different natural settings. The aircraft sound signatures were detected by numerous monitoring stations set up throughout the study territory. When an aircraft flew over the park, the display would show a cartoonlike colored moving overlay with the symbol of an airplane and a radiation pattern representing the output of its sound, thereby defining the range over which the signal could be detected.
The intention of the study was to show park managers how they could oversee the soundscape experience of visitors. Aircraft noise, however, is a lot less subtle than the myriad sounds of a biophony.
Usually, when I wish to know how a territory is defined—whether by geological features or by boundaries of cities, parks, or private land—I reach for a map filled with grids or turn to imagery from services such as Google Maps. But in order to show how the natural soundscape can be used as a different means of defining a biome’s borders, a few colleagues and I initially worked within the limits of 100 square meter grids that had been meticulously laid out by etymologists, botanists, ornithologists, and herpetologists at several subtropical forest research sites, such as La Selva in Costa Rica. We looked for periods of day or night when the biophonies remained constant and then we walked through the grids, crossing them at different angles, listening for zones and recording where the mixtures began to change.
On listening to playback, analyzing the notes from on-site observations, and comparing spectrograms, we found that the combined creature voices defined territorial boundaries quite differently than the geographically detailed maps we held in our hand. For one thing, it was clear that the margins characterized by the soundscapes didn’t align with the human grid lines or other rational borders we might create. Nonhuman animals don’t understand 100-meter-square grids or, for that matter, county, state, and country margins. At the point where the spectrogram partitioning began to show changes in biophonic structure, we knew we had reached an acoustic perimeter. We redrew the charts with overlays that reflected these new findings, then plotted a number of acoustic sectors and replaced the square grids with our new boundaries—borders that partitioned the map into amoebalike shapes, each an acoustic region that, while mutable, would tend to remain stable within a limited area over time. Working within the technical limitations of our first attempt, we realized that in order to derive more accurate information, we would need a vast network of stand-alone, data-rich, synchronized monitoring devices spread out at regular intervals throughout the habitat as well as more detailed spectrogram software—practical technologies that had not yet been realized but that are now becoming commonplace. Nevertheless, the initial implications from the data we did collect were striking.
The unique characteristics of each separate habitat are reminiscent of the signature sounds that permeate the body of a composer’s work. Anyone even vaguely familiar with Mozart and Aaron Copland can instantly tell the difference between their two styles. No less passionate, the carefully structured compositions of Mozart are extremely formal and constricted in comparison to the more open neoclassic and symphonic themes generated during the early twentieth century. Just as a dedicated listener of classical, pop, or jazz music can identify the individual sound signature of a group or composer, those of us who have enough acoustic and dynamic detail stored in our heads can determine the time of day or night and the precise region we’re hearing by simply listening to an audio recording of a biome for a few seconds. The natural voice themes become as clear as the main theme in Beethoven’s Ninth Symphony, fourth movement.
While mapping, we noticed again that insects tended to create niches that remained constant in each biome for long periods during each day and night. Also, when one sound source dropped out at the end of its cyclical performance, another usually began to vocalize, typically within seconds, leaving the impression that replacement was necessary to keep some underlying acoustic-bandwidth structure intact. Over these “group” performances we could hear animal “soloists” who appeared for brief periods—often transient birds, mobile amphibians and mammals, and other organisms that would move in and out of the primary acoustic field. Like an eight-bar blues solo on guitar, their voices, too, seemed to fit into acoustic channels or temporal niches where little or no conflicting aural energy was present.
One great adaptive advantage of having all of the contributing voices of a habitat partitioned into niches is that the whole within an entire niche configuration often sounds more vital, rich, and powerful than the sum of its parts. The harmonic content of the drone voices—insects and chorusing frogs, for instance—sometimes adds what in music terms is called frequency or amplitude modulation. Another example of frequency modulation is vibrato added to a note played on a violin. If a violinist is playing a C-natural in the second position on the A string, she can modulate the C seven or eight times a second by rolling her finger back and forth, a bit flat and sharp of C’s 523 Hz, adding an effect that musicians call vibrato. If the violinist periodically varies the volume of the C in much the same way, she would be modulating the amplitude.
Sometimes all that insect and amphibian racket creates intermodulation, where two or more signals are so close in pitch that they occasionally beat against each other, momentarily canceling each other’s signal—a totally different acoustic effect than any of the original sources sounding individually.
Each cohesive habitat expresses itself through its own special niche composition—its unique voice. Think of moving from one biophonic territory to another as moving along the path of an acoustic spectrum—from low to high frequency, from one point in time to another through space. In the case of biophonies and geophonies, the bioacoustic spectrum is completely biomedependent—biophonies are universal only in the sense that they exist nearly everywhere natural soundscapes are experienced. Each biophony is as different in texture as our own vocal signatures.
When modern humans first appeared in the tapestry of the biosphere, they had to be quick studies, categorizing their knowledge of the acoustic environment in ways that could be useful. Our ancestors would have understood that some sounds could be a practical means for survival. To the extent that people’s existence depended on a harmonious relationship with their surroundings, a dialogue with the forest became an imperative. Louis Sarno, a musical anthropologist from New Jersey who has been living with and recording the music and natural soundscapes of the Babenzélé pygmies (Ba’Aka) in the Dzanga-Sangha forest of the Central African Republic since the mid-1980s, often tells the story of how the young children of the Ba’Aka seem to know, almost instinctively, not only the practical meaning of sounds within the forest soundscape—as related to sources of food and danger—but also the social signals (spirits, inspiration for music, and even occasional linguistic expression).
Close links between humanity and the soundscape have always been an essential lens through which we understand the world. Our kno
wledge of biophonies and how they change over long periods of time and under a variety of climactic and seasonal circumstances enhances our modern geological, topographical, and floral distribution scope of understanding, providing details not likely to be captured in satellite imagery or topographical mapping sequences. Those of us living close to the natural world have learned the permutations of these dynamics well. It is likely that buried deep within the human limbic brain is ancient wiring that springs to life every time we reconnect with these delicate webs of acoustic finery—the multiple layers of resonance that still exist in parts of the wild.
It didn’t take early humans long to find useful ways of incorporating biophonic information into hunts, ceremonies, language, and the dialoguing exchanges of music—our first organization of sound.
CHAPTER FIVE
First Notes
Each of us consumes a world of sound, but our primary soundscape defines our environment. As a child, mine comprised the range of sound from our home and the surrounding open fields and woods. When I was around two years old, my family moved to what was then a transitional zone between urban and rural Detroit—former Midwest farmland where bird and insect sound still flourished but where the remaining landscape would be altered shortly after World War II into modest, middle-class, red-brick housing. This was an epic transformation from the vast, heavily wooded moraine shaped by the last glaciers to the compressed mass that would define much of postwar urban America.
Our unassuming home was badly insulated for weather and sound. Even with the windows shut tight, birdsong from the fields and occasional traffic from the street blended with the interior clamor of the Krause family. Because of my compromised vision—the result of astigmatism and farsightedness—sound was the sensory element that most captured my imagination and helped me find my way in the world. Despite our location at the corner of what would soon become a busy intersection, when we first moved I would listen to exotic dawn and evening choruses—birds, insects, and occasional frogs from the surrounding fields, which hadn’t yet been dissected into lots for more homes like ours.
My tiny room, just large enough for a crib or a small single bed, was located on the second floor, in the back of the house above the kitchen. It was the farthest from the street, facing northwest and looking across what, to a young child, were vast open fields. During spring it was infused with daybreak and dusk songs of mourning doves, wood warblers, cardinals, chickadees, vireos, robins, starlings, pheasants, amphibians, crickets, and a variety of insects. I came to know the sounds of the nonhuman creatures of my youth very well. They were mixed with doors that would creak, click, and snap open and shut as the humans in the house rose each morning. Plumbing would spring to life from the bathroom down the hall. The sounds of clattering pots, plates, and silverware would rattle up through my floor with a reassuring timbre when my dad got up early and ate breakfast before heading off to work. Most evenings before bedtime, crowning the normal sounds that filled each day, an announcer’s voice or the sound of music would rise from the old Philco radio and record player sitting in the far corner of the living room.
After everything was shut down for the night, my dad would come to my room and read stories. I especially liked the tales that evoked acoustic events—pirate yarns; legends of giants, their huge feet thundering across the landscape; ancient battles; children lost in the woods, obsessed by mysterious noises. In the end, however, it was the faithful combination of the whip-poor-will and crickets outside my window that finally lulled me to sleep.
The house itself, a fifteen-hundred-square-foot home typical of many prewar dwellings of the time, had its own voice: the walls oscillated and thudded slightly with a low-frequency shudder—felt more physically than aurally—when it was windy and the pressure on one side of the building was different from that on the other. And as the wartime Detroit industrial population exploded, other houses filled vacant lots where we once kept a victory garden, streets were paved, birdsong disappeared, and we found ourselves surrounded by the din of ceaseless human enterprise. All of those early soundscapes are still clear in my mind—I’d recognize them instantly if I heard them again. No picture of our family, our home, or our surroundings can even begin to convey the animation of that environment as well as my memories of the sounds inside and outside that house.
Before I was five years old, my first soundscapes were replaced with music. I began to study violin and composition. Beethoven, Mozart, and Vivaldi, my favorite composers, were soon traded for a world of jazz that my parents’ friends introduced me to. As that domain opened up and I began to ask questions about the nature of sound and music, my queries were mostly met with blank stares from my parents and their friends. Even my violin and composition teachers knew little beyond the notes on the page, the accepted range of their principal instruments, and the literature they had been exposed to. The instrumental choices my parents imagined for me—violin and piano—were as conventional as their future academic and professional visions, which centered on either law or medicine. They would never understand or quite accept why I chose the path I ultimately settled on.
As a teenager, I switched to guitar and became fluent in all styles. My choice to leave the violin behind was met by expressions of dismay and a historic number of pursed lips. From that moment on, my parents never looked forward. I never looked back. When I applied to the schools of music at Eastman, Juilliard, and the University of Michigan in 1955, I was essentially rejected on the grounds that the guitar was not a musical instrument.
A couple of years after graduation from college, while I was working as a professional studio guitarist, the folk music quartet the Weavers invited me to audition for the venerated Pete Seeger tenor slot. I was one of many artists who sent in performance tapes and risked a live audition. To my great surprise, I made the final cut and debuted with the group at their historic 1963 Carnegie Hall reunion concert, where—with Pete, Ronnie Gilbert, and Fred Hellerman—we introduced “Guantanamera” to the American public.
Around the time of the Weavers’ split in early 1964, musicians began experimenting with modular synthesizers such as the Buchla and the Moog. From the moment I first heard one, I knew that that was the kind of innovation I wanted to learn about and use. That’s when I moved to California and began to work with Paul Beaver. Through the questions that arose during our L.A. synthesizer workshops, we constantly challenged old assumptions and definitions of music.
By the time Paul and I wrote and recorded The Nonesuch Guide to Electronic Music in 1967—an introduction to analog synthesis and performance—we also felt compelled to address the ways in which the synthesizer shed new light on long-held ideas about sound and music. Foremost on our minds was a basic question: What is music? Definitions of music vary widely from culture to culture, within given societies, and even from person to person.
With the advent of sound synthesis, Paul and I thought we could reduce complicated definitions of music to a single fundamental equation, like E = mc2, by asserting that music, in the human realm, is simply nonlinguistic and conscious control of sound.
There were many reasons we arrived at this controversial explanation. For one, it seemed to fit all societies that venerate music and musicians, since a performer must—in order to create music as we know it—at the very least decide on which sound sources to control and how loud and long each sound in the sequence will be heard and expressed. In the end, it turned out that our definition was missing at least two other important factors: structure and intent.
As I became familiar with music of all types, I realized that fundamental to each form are vertical patterns—that is, instrumental texture and layering—and horizontal, or time, patterns. A particular combination of vertical and horizontal patterns gives each musical form a unique definition. A modern Greek band, for instance, might consist of a bouzouki (a three-stringed lutelike instrument), a toumbeleki (a small metal drum), a regular Western guitar, a defi (a tambourine-like percussion instrument)
, a violin (Western style), and perhaps a tambouras (the ancestor of the toumbeleki but with up to six strings). Central to the structure of the sound are stringed and percussion instruments, along with lead and occasional backup vocals.
A Balinese gamelan orchestra, on the other hand, stresses the sound structure of metallophones, xylophones, gongs, flutes, and the human voice. The Greek vertical structure is based primarily on Western twelve-tone musical tuning, while the gamelan orchestra tunings feature either five or seven notes to an octave. The plucked and bowed string textures of the Greek band will sound very different from the hammered metallic fabric of the Indonesian ensemble.
Horizontally, the structures of many Greek folk songs are propelled along with lively tempi and 5/4 and ⅞ time signatures. Gamelan music, alternatively, consists of several basic rhythmic styles of interlocking beats that unfold in hypnotic patterns throughout each piece. When these two structures are compared to American country music, with bands typically made up of guitar, bass, mandolin, fiddle, five-string banjo, a drum set, lead vocals, and tight backup harmony, vertical and horizontal organization becomes quite clear. Structures of these types are inherent in and seminal to all musical forms and have been one of the defining variables of every sonic performance humans have engaged in.
Intent is the easy part. How many of us have ever picked up or sat down at an instrument without intending to generate some kind of sound—especially when we discover that the object of our momentary curiosity produces one? When a two-year-old child sits on her parent’s lap at a piano keyboard and strikes those first notes with her fist, she realizes that she’s created something engaging and immediately becomes fascinated with trying to produce a similar result by doing the same thing again. Then she’ll strike a higher or lower fistful of notes on the keyboard. Soon enough, if she’s encouraged in the right way, this young Björk will find a melodic or textural line she particularly likes and adopt her own filters through which to project her own special voice.
The Great Animal Orchestra Page 10