The Niche Hypothesis: How Animals Taught Us to Dance and Sing
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The Niche Hypothesis: How Animals
Taught Us to Dance and Sing
By Bernie L. Krause, Ph.D.
N
ative Americans have long been aware a valley just south of the lake and motioned for me
that there is a symphony of natural to sit on the ground. I immediately began to shiver
sounds where each creature voice performs in the cold October air but continued to sit for the
as an integral part of an animal orchestra. They are better part of an hour, every now and then watching
not alone. Indigenous cultures throughout the Angus, who was sitting quietly about 50 feet away
world are keenly aware of the power and influence of upstream. For a long while, except for a few jays and
natural sound in each of their musical creations. As ravens, nothing happened. Suddenly, a slight breeze
an artist and naturalist, I have long been fascinated coming from up the valley began to stir some of the
by the ways in which hunters from non-industrial branches and the forest burst into the sound of a
societies determine types, numbers, and condition of large pipe-organ chord appearing to come from
game and other creatures hundreds of meters distant everywhere at once. Angus, seeing the startled look
through dark forest undergrowth by sound where on my face, walked slowly to where I was sitting and
nothing appears to the Western eye or our untrained said, “Do you know what makes the sound, yet?”
ear to be especially distinct. As we are primarily a “No,” I said. “I have no idea.” He then walked over
visual culture, no longer connected to what environ- to the bank of the stream and, kneeling low to the
ments can tell us through sound, we’ve lost aural water’s edge, pointed to the different length reeds
acuity once central to the that had been broken by the
dynamic of our lives. wind and weight of the newly
While working with formed ice. He took out his
the Nez Perce in Idaho and knife and cut one at the base,
central Washington in the late whittled some holes, brought
60s and early 70s, a tribal the instrument to his lips and
elder by the name of Angus began to play a melody. When
Wilson suddenly became very he stopped, he said, “This is
silent when I told him I was a how we learned our music.” It
musician. “You white folks wasn’t until ten years later,
know nothing about music,” while recording in the forests of
he said, teasing me. “But I’ll eastern Kenya that that morn-
teach you something about it ing at Lake Wallowa came to
if you want.” Early the next mind again. It was there that I
morning we headed out from began to wonder about the
Lewiston to Lake Wallowa importance of natural sound to
into northeastern Oregon...to the entire context of our
one of the many ancient survival and our cultural
campsites of Chief Joseph and success.
his small band prior to 1877. Since the end of the 19th
Wilson led me to the bank of Century, biologists and zoolo-
a small stream coming out of Bernie Krause in the field recording gist have been focusing their
1research in large part on the study of singular crea- the subtle differences in sound between the various
tures in an effort to understand an organism’s con- mini-habitats (as small as 20 sq. meters) in a forest,
nection to the whole environment. Isolated studies even when these localities appear to have visually
were always easier to grasp and measure within the identical biological and geological components.
canons of pure and carefully considered academic More likely than not, even when travelling in total
terms. Study controls were easier to impose. And darkness, these remarkable groups appear to deter-
quantified results have been the proverbial means to mine their exact location simply by listening. Fur-
heaven’s gate...at no little cost to comprehensive thermore, when we closely observe the effects of
knowledge. Indeed, even in the relatively new field chimpanzees, Mountain Gorillas and Orang-Utans
of bio-acoustics (bio = life, acoustics = sound) where pounding out complex rhythms on the buttresses of
feasible recording technology first emerged in the rainforest trees, one cannot help but be struck by the
late 60s, field researchers have earnestly sampled articulation of the message, its effect on other groups
single creature sounds and have tried to isolate of primates in the vicinity of the sounds, and the
individual animal vocalizations only to find that natural origins of the human art of drumming and
significant parts of the messages have eluded them making music.
altogether. Experienced composers know that in order
In a recent essay on this subject, Stephen Jay to achieve an unimpeded resonance the sound of
Gould spoke of “...the invisibility of larger contexts each instrument must have its own unique voice and
caused by too much focus upon single items, other- place in the spectrum of events being orchestrated.
wise known as missing the forest through the trees.” All too little attention has been paid to the fact that
(“Abolish the Recent,” Natural insects, birds and mammals in
History, May, 1991, pages any given environment have
16-21.) Later in the been finding their aural
article Gould suggested that niche since the beginning of
we have a great deal of time...and much more suc-
difficulty grasping the larger, cessfully then we might have
more complex concepts - even imagined. Indeed, combining an
when they may hold the key to audition with a graphic print-out
simpler truths. Bearing this in of the diversity and structure of
mind, we are just now begin- natural sounds from a rainforest
ning to realize the important rôle forcefully demonstrates very special
ambient sound plays in our environment. Ab- relationships of many insects, birds, mammals, and
stracting the voice of a single creature from a habitat amphibians to each other. A complex vital beauty
and trying to understand it out of context is a little emerges that the best of sonic artists in Western
like trying to play Samuel Barber’s “Adagio for culture have yet to achieve. Like the recent ac-
Strings” absent a violin section as part of the orches- knowledgment that medicine owes much to
tra. rainforest flora, it is my hunch that the development
From what we have just begun to see, it our sound arts owes at least as much to the “noise” of
appears that ancient human beings had learned well our natural environments.
the lessons imparted by natural sounds. Their lives Based on R. Murray Schafer’s exceptional
depended as much (if not more) on their ability to vision of sound, the premise that soundscape ecology
hear and understand the audio information imparted or the study of sound in any environment provides
by their surroundings as those given by visual cues. important clues as to “the effects of the acoustic
Small enclaves like the Jivaro and other tribes of the environment... or the physical responses or
Amazon Basin survive using this information today. behavioural characteristics of those living within it”
Not only can these extraordinary folks distinguish (Handbook for Acoustic Ecology, B. Truax, Ed.,
one creature sound from another but they recognize ARC Publications, 1978), we are just beginning to
2Insects
8K
6K
4K
2K
Lesser Antilles Swift (Chaetura martinica) Mourning Dove (Zenaida macroura)
0 10 Seconds
Pic Paradis, St. Maarten
Figure 1
listen more symbiotically to sound in our varied seem to have been aware that each creature appears
environments. What our ancestors knew and what to have its own sonic niche (channel, or space) in the
successfully guides many forest inhabitants today is frequency spectrum and/or time slot occupied by no
the knowledge that every zone in any given environ- other at that particular moment. Taking a giant leap
ment, where the natural habitat is still completely when considering the habitat as a whole, the sounds
intact, has its own unique voice. Sometimes, if one of each of these zones are so unique and important
moves just 10 or 20 meters in one direction or to creature life in a given location, if one creature
another in any old-growth habitat, the sound will be stops vocalizing, another immediately joins the
quite different even where there is similar vegetation chorus to keep that audio bio-spectrum intact. An
and climate. audio bio-spectrum is a acoustical spectrographic
From the early bio-acoustic mapping of any particular habitat by
studies we have done, I believe we frequency (pitch, sometimes tone) and
have recently discovered some amplitude (loudness) over short periods
evidence of the roots of ancient of time.
musical composition...something which Territory is now defined in
has evolved over time and from dimensions well beyond the 3-D
which ancient human beings topographical. In younger habi-
learned some pretty complex tats birds and mammals will
formulae. First of all, these folks occupy only one niche at a time.
316K
12K Asian Paradise Flycatcher
(Terpsiphone Paradisi)
8K
4K
Brown Barbet
(Calorhamphus fuliginosus)
Ferruginous Babbler
(Trichastoma bicolor)
0 10 Seconds
Kalimantaan, Borneo
Figure 2
However, in older environments, disappearing Latin American
some tropical rainforest animal winter nesting grounds.
vocalizations, like the Asian paradise Where these environments
flycatcher (Terpsiphone paradisi), are so have been deforested, and when
highly specialized that their voices birds try to move to nearby and
occupy several niches of the audio bio- ostensibly similar or secondary
spectrum at the same time thus growth habitats, they discover that they
laying territorial claim to are unable to be heard. Our studies are
several audio channels. From beginning to show a strong likelihood
our observations of the Asian that survival might be impaired
paradise flycatcher, we suspect because territorial and/or gender
that we will soon be able to related communications are masked.
utilize this acoustical method- Figures 1 and 2 show simple and
ology to help determine the age complex habitat ambient niches where consis-
of certain habitats. Not a few migrating eastern tent dark lines running horizontally across the page
American warblers, able to learn only one song and represent a unique mixtures of insect voices shown
call in their lives, find themselves unable to adjust to occupying several “bands” of a 20 - 10,000 Hertz
the changes in ambient sound when they fly to their frequency spectrum in Figure 1 and a 20 - 20kHz
4spectrum in Figure 2. would often wait for up
The darker the line, the to 30 hours in one
greater the amplitude in location for a desired
that particular range. The event to take place.
short lines toward the Out of boredom and
bottom of the page in because there was
Figure 1 represent the low nothing else to do at
voice of a Zenaida dove, a the time, we began to
species of bird living in record pure ambient
the Virgin Islands on St. sounds. When a bird
Maarten. This sample sang or a mammal or
was taken on Pic Paradis, amphibian vocalized,
a 400m mountain on the the voices appeared to
French side. The Figure fit in relation to all of
2 sample was recorded the natural sounds of
recently in Borneo. the immediate environ-
Again, the consistent ment in terms of
horizontal lines running frequency and prosody
across the middle of the (rhythm). Over a
page represent insect number of years we
voices. However, notice would return to the
the Asian Paradise fly- same sites only to find,
catcher (Terpsiphone when the recordings
paradisi) vocalizations at were analyzed, that each
both the left and right place showed incredible
sides of the page. Its Krause in the field bio-acoustic
voice is made up of three consistency...much like
harmonic components called formants. And they fit we would expect to find from fingerprint matching.
uniquely and exactly into several niches where there The bird, mammal and frog vocalizations we re-
is little or no vocal energy represented by the light or corded all seemed to fit neatly into their respective
white spaces. It turns out that in every unaltered niches. And the bio-acoustic niches from the same
habitat we have recorded, many birds, mammals locations all remained the same (given time of year,
and amphibians find and learn to vocalize in acousti- day, and weather patterns). Having just begun to
cal niches unimpeded by the voices of less mobile work in Indonesian rainforests, early analysis indi-
creatures such as near-ranging insects. cates similar results from each of the biomes we have
We first noticed this phenomenon while visited and recorded.
working in Africa in the early 80s. Many habitats While the audio bio-spectra of each location
have been recorded since. To obtain these recordings remain essentially constant, large habitats of the
we would typically spend 500 hours on site to get 15 same region will show local variability and regional
minutes of usable material...a ratio of 2,000:1. The similarities, all at the same time. However, each
long wait is due primarily to the introduction of area generates its own unique voiceprint and can be
human-induced mechanical noise(s) like chain saws identified by sonogram. We find this to be particu-
(from 20 miles away), aircraft, motorized riverboats, larly true where the density of living organisms is
etc. To date, our library consists of approximately greater such as tropical rainforest habitats. As more
3,500 hours of material...20% of it from now-extinct creatures vie for acoustical space, the ability to clearly
habitats. articulate a voice within that space is more critical to
While recording species-specific creatures, we each species’ survival. As would be expected,
5acoustical definition changes as we move away from keep ourselves separated from the notion of “nature.”
the equator north or south to more temperate zones. The use of the very word, itself, sets us apart. It is
In these habitats, creature voices and well-defined interesting to note that no Native American word for
acoustical spaces are determined by more loosely “nature” exists in any language of the 500 nations.
tangible criteria. We do not to use it to describe any of our work.
If, as we are suggesting, the ambient sound Natural orchestrations, the sounds of our
of primary growth habitats functions much as a unaltered temperate, tropical, arctic, desert and
modern day orchestra with each creature voice marine habitats, are becoming exceedingly rare and
occupying its own place on the environmental music difficult to find. The keys to our musical past and
staff relative to frequency, amplitude, timbre, and the origins of complex intra-species connection may
duration of sound, then there is a clear acoustical be learned from the acoustic output of these wonder-
message being sent as to the biological health of ful places. We are beginning to learn that the
these locations. Some people, believing that fragile isolated voice of a song bird cannot give us very
environments can be continuously and endlessly much useful information. It is the acoustical fabric
developed, must begin to listen, as well as observe into which that song is woven that offers up an elixir
what changes are taking place. Developmental of formidable intelligence that enlightens us about
advocates suggest that if just small biological islands ourselves, our past, and the very creatures we have
are preserved, that will be enough...especially for the longed to know so well.
development of eco-tourism. ‘Life is too short not
to get as much as we can out of it.’
However, it has been shown in our own
country from work done in North American na- Glen Ellen, California
tional parks that species are becoming extinct and
that they are doing so in an inverse relationship to
the size and age of the parks and at an increasing
rate. The smaller the park, the faster the decay.
When we have tried to record in new stands of trees
planted in the Olympic peninsula by Georgia-Pacific
and other lumber companies, we have found a
profound lack of bio-diversity evidenced first by the
obvious monoculture of corn-rowed stands of fast-
growing pines and very little supporting vegetation
growing on the forest floor, but more so by the
overwhelming silence. Compare these recordings
with those of nearby healthy old-growth forests and
the measurable differences are astounding.
Research continues on the issues suggested
by this hypothesis. The study of acoustic ecology W i l d
began in the late 70s and has just recently begun to
be considered as a valuable tool for defining the S a n c t u a r y
health of both marine and terrestrial habitats around
the world. Adding this information to the body of
knowledge is important for many reasons not the This article first appeared as "Bioacoustics, Habitat
least of which is rediscovery of a direct cultural link Ambience in Ecological Balance," Whole Earth
to our natural surroundings before they all disappear. Review, #57, Winter, 1987.
For the past two centuries Western academics,
writers, and artists have labored at some length to © 1987-1998 Wild Sanctuary
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