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THE PORPOISE-SONAR PROJECT AT FSU'S MARINE LAB
Between 1952 and 1956, Kellogg worked closely with Robert Kohler at FSU's marine lab at Alligator Point, on the Gulf of Mexico just south of Tallahassee, to carry out a project investigating the possibility that porpoises use sonar in navigation and foraging. Bob Kohler was a skilled engineer, with great practical smarts and creativity who, in today's terminology, was a one-man "Technical Support Group" for the entire campus at that time. The first two papers from this project were published in Science in 1952 and 1953, with Kohler as a co-author.
- Winthrop Kellogg at FSU Marine Lab,
(early 1950s)
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- Bob Kohler at FSU Psych Dept Lab (2002)
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How Kellogg's Porpoise Research Got Started: Bob Kohler's Account
During this time [circa 1951] I got involved with Dr. Kellogg of psychology. I had done a lot of work for the psychology department as a whole and got to know Dr. Kellogg. One day we went out on his sailboat, and we were just sailing along -- he had a beautiful little sailboat -- just sailing along and here come the porpoises right up by the bow riding the bow wave. This was in the summertime. He was looking at those things. This guy had more sense under his fingernails than I have in my head, you know. He was really a sharp nail. He looked at the porpoises, and he looked at the water, and we passed a stake or something in the water -- you know a fisherman would always mark a place by driving a stake down in the bottom. And he'd say, "Bob, how do they keep from running into these stakes? Or for that matter, from running into the boats." And, just joking, I said, "Maybe they have sonar." I knew that bats had sonar, and so did he. In fact, another man named Kellogg is the one who discovered this, and there's no relation. Anyway, Kellogg decided by gosh he was going to find out, so he started working on the porpoise problem. From: Robert Kohler's Oral History (1999), The Reichelt Program for Oral History, Florida State University.
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Kellogg's entire research program on porpoises was summarized in several papers and particularly in his book: W.N. Kellogg (1961) Porpoises and Sonar. Chicago: University of Chicago Press. In the material that follows, we highlight main points of the project as described in Kellogg's book. However, we urge you to look at a longer and fascinating excerpt from Robert Kohler's Oral History which provides an untold perspective on Kellogg's famous porpoise work and a case study of how behavioral-research methods were combined with state-of-the-art technology in FSU's Psychology Department in the 1950s. The Department's research has reflected that combination ever since expanding and maintaining a world-class Technical Support Group. Kohler's account provides a unique perspective on how the porpoise work got started and how it proceeded, and is an excellent case history in the scientific method.
THE
PROJECT
"The project. . . .was sponsored and supported
by the Office of Naval Research (ONR) and the National
Science Foundation(NSF). The ONR lent indispensable
underwater sound gear, and the NSF gave financial aid in
the form of substantial research grants. Additional funds
for carrying on the work were obtained from the
Psychology Department, the Oceanographic Institute and
the research Council of Florida State University
(Porpoises and Sonar, 1961, p.IX)."
THE
GOALS OF THE PROJECT: KELLOGG'S STATEMENT
The goals of the project were
summarized in Porpoises and Sonar (1961):
"[The] [o]bject of the series of
investigations. . . .has been to demonstrate the
process of sonar or echo-ranging in the bottle nose
dolphin, Tursiops truncates. [I] wanted to
find out if a dolphin or porpoise could locate food
objects, like fishes, by bouncing echoes off the
fishes' bodies. [I] wanted to discover whether
it could avoid submerged obstructions by using its
ears alone. [Kellogg] wanted to learn if it
could navigate at night or in turbid water without
employing vision, tough, or any of the chemical
senses. To do this under controlled conditions,
[he] had to eliminate all of the other sensory
avenues which these animals might conceivably make use
of in such situations. The research program as a whole
has included both wild or free-swimming, as
well as captive, porpoises." (Porpoises and
Sonar, 1961, p. 151)
"[The] study of porpoise sonar has been
divided into three main steps or stages. First,
[I] analyzed the sound pulses which these
animals emit for the purpose of echo-ranging.
[I] sought to determine whether any of their
water-borne noises possess the necessary temporal and
acoustic characteristics for proper use as sonar
signals. Second, [I] turned to the receiving
side to find out if the echoes from porpoise sound
pulses could be adequately decoded and analyzed.
Lastly, [I] studied the porpoise in action by
examining its ability to use its own sound signals in
navigation and in orientation. This last stage has
taken up the greater portion of the book"
(Porpoises and Sonar, 1961, p. 152)
THE LAB AT
ALLIGATOR POINT

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Kellogg, Kohler and others working with porpoises at the FSU Marine laboratory (circa 1953)
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Kellogg (center, in ball cap) setting up for a
testing session at the lab (circa
1953)
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Apparatus used for analyzing porpoise sounds.
The equipment shown here produced the photographs
of echo-ranging pulses seen next . (1)
Audio-amplifier. (2) Loud-speaker. (3) Oscilloscope
camera. (4) Cathode-ray oscilloscope. (5)
Audio-oscillator (for calibration). (6) Band-pass
filter. (7-7') Ampex tape recorder from which
porpoise noises are sent to oscilloscope. (8)
Auxiliary recorder
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SOME MAIN
RESULTS
DESCRIPTION OF
PORPOISE SOUNDS
"The underwater sounds which porpoises
produce[d] most often [were] successive
series of rapidly repeated clicks or pings. These noises
[were] analyze[d] acoustically by several
methods and in several places. [The noises]. . .
.contained a wide band of both sonic and ultrasonic
frequencies extending as high as 170,00 cycles per
second. Echoes from such clicks have been measured and
photographed." (Porpoises and Sonar , 1961, p.153)
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Oscilloscopic photographs of porpoise
clicks or sound pulses used in echo-ranging.
(Top) Filmstrip showing a brief train of
porpoises clicks beginning about half-second
after a surface splash. Several harmonics are
indicated by the different densities of the
spikes. The noise of the splash is shown at the
left of the film. The clicks in this picture
were photographed live as the porpoise made
them. (Bottom) The same train of sound-pings
photographed from the play-back of Ampex
magnetic tape. The two pictures will be seen to
be identical except for a slight AC modulation
in the base line of the lower photograph.
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(Top) Photograph of the cathode-ray
screen of a panoramic ultrasonic analyzer,
showing frequency components occurring between
80 and 120kc. in a series of porpoise clicks.
Separate pips represent coincidence of the sweep
of the cathode-ray tube with different clicks.
Twelve clicks that occurred during the
photographic exposure (0.5 sec. in this
instance) thus contained frequencies extending
at least to 120kc. (Bottom) Photograph of the
cathode-ray tube of the panoramic analyzer when
the tuning range was 10-200kc. The strongest
frequencies, so far as intensity is concerned,
will be seen to lie below 25 kc., but the short
pips at the right indicate the presence of
frequencies of 140, 155, and 170 kc.,
respectively.
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Underwater photograph shows animals
examining a hydrophone which was submerged in
order to pick up their sounds. (Courtesy Marine
Studios)
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A series of clicks expanded laterally
on this 35-mm. Filmstrip so to show echoes. The
large vertical spike represents the original
pulse, and secondary spike immediately to the
right of each pulse is its echo.
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THE
PORPOISE SONAR SYSTEM - EAR AND
BRAIN
"The ear and brain of the animal have
been shown to be highy advanced in development.
They possess important adaptations for the
perception and analysis of underwater sounds.
The acoustic receptor is able to compensate for
changes in external pressure due to water depth.
Porpoises have a much greater range of hearing
than human beings and, consequently respond to
many vibrations in the field of ultrasound. The
unusual sonar pulses which they send out, and
the excellent receptor which they possess,
constitute an acute transmitting-receiving
mechanism. The brain, moreover, adapted as it is
to the sense of hearing, appears to be well
equipped to act as a decoder and computer for
the neural impulses reaching it." (Porpoises
and Sonar, 1961, p.153)
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Diagram showing probable action of the
blowhole in closed (left) and open (right)
positions. The external valve and the
anterior-posterior projecting processes are
indicated. Auditory vibrations could conceivably
be made whether by the lip of the blowhole, or
lower down in the passage (modified from
Howell).
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A comparison of the brain cavity of a
porpoise with that of an adult human being. The
tops of the skulls were sawed off of these
diagrams. The human skull is on the left. The
frontal portion of both skulls points upward.
The lateral dimension of the porpoise brain is
greater than its anterior-posterior dimension.
This is reversed from the proportions of the
human brain and that of other mammals.
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BEHAVING WITHOUT
VISION
"Another way of eliminating vision which proved
effective was to conduct tests during the night, when it
was so dark 'you couldn't see your hand before your
face.' Still a third method was to immerse invisible
obstructions, like sheets of plate glass and transparent
Plexiglas, and to see whether the animal could avoid
colliding with them. (Porpoises and Sonar, 1961,
p.153)."
DISTINGUISHING
BETWEEN FISHES
"[I] learned. . . .porpoises are able to
differentiate between food-fish of different sizes by
listening to the echoes reflected from the fishes'
bodies. This came to light in a discrimination
experiment. In the tests which were made, the two fish to
be distinguished not only had different reflecting areas,
but they were also of different species. One of the
fishes was distasteful or unpalatable to the porpoise,
and it would reject this variety of fish even after it
had one in its mouth. The other or "positive' food-fish
was a species which was much sought after." (Porpoises
and Sonar, 1961, p.155)
The turbidity of the
water acted somewhat like a one-way-vision screen.
The experimenters above the water level could see
sufficiently far beneath the surface to observe the
porpoise's head and mouth, but the animal could not
detect the target fishes in a horizontal direction.
The difference between the absolute threshold for
distance and the differential
threshold-to-threshold of discrimination between
the target fishes is also illustrated in this
figure.
AVOIDING INVISIBLE
SURFACES
"In another situation, a pair of desirable or
preferred food-fish were used as rewards. Each fish was
now identical in size and visual appearance; yet the
arrangement was such that one of the paired fishes was
always offered behind an invisible sheet of plate glass.
The remaining fish was readily available and could be
taken and eaten by the animal. The glass was sometimes in
front of the right-hand fish and sometimes in front of
the left-hand fish. If a porpoise relied on vision in
such a situation, it would certainly make some approaches
to the glass. Yet, because a sheet of glass 'sounds
different' from a small fish, no mistakes at all occurred
in more than 200 trials (Porpoises and Sonar,
1961, p.155)."
Plan of the
net experiment. A steel net or fence was
stretched tightly across the porpoise pool
beneath the water, dividing it into two
sections. Two openings or doorways in the fence
permitted the animals to swim from one section
of the pool to the other. A heavy sheet of clear
Plexiglas was used as a barrier to block one of
the openings. An opaque plastic curtain,
manipulated from the bank, was lowered between
trials to cover both openings.
EXPLORING WITH
SOUND
"During intensive work with two experimental
subjects, many interesting discoveries came to light.
[Kellogg] found, for one thing, that the noises
of a splash upon the surface of the water inevitably
triggered a series of porpoise sound pulses. The animals
appeared to be "looking with their ears" to find out if
some foreign object had entered the water. If a splash
was made alone, without the immersion of a target, the
sputtering signals stopped after a few seconds. When a
splash was followed by the presence of some new object in
the water, exploratory sound signals continued-presumably
until the size and distance of the object had been
determined (Porpoises and Sonar, 1961, p. 154)."
RUNNING AN
OBSTACLE COURSE
"Thirty-six sheet-metal poles were suspended
over an enclosed area. These could be simultaneously
lowered into the water by assistants who operated tackle
from the shore. Only a limited space was allowed for
movement between these submerged obstructions. Each pole
gave off a bell-like ring when touched or struck, so that
collisions were automatically registered on
sound-recording tape even though they could not be seen.
A few collisions occurred at first, but as soon as the
[porpoises] got used to making the short and
difficult turns required in this situation, the errors
ceased. Even at night, there were no further collisions."
(Porpoises and Sonar, 1961, p. 156)
General
design of the outdoor "porpoise laboratory." The
dimensions of the pool were 55 by 70 feet.
Overhanging cables between rows of telephone
poles to the east and west were used for
supporting underwater apparatus or partitions. A
small crane or hoist to the south permitted
lowering of heavy acoustical equipment.
SUMMARY AND
CONCLUSION
The major contribution of the Porpoise and Sonar
(1961) project was not that porpoises made sounds, which
had been recorded by the US Navy in the early 1940s, but
what the sounds were used for. The findings were even
viewed as "
have a bearing on national defense, as
a means of improving Navy sonar or echo ranging of the
porpoise is superior in many respects to the best that
man has yet been able to develop
" (Porpoises
and Sonar, 1961, p.152).
In a second porpoise project carried out in California
after Kellogg left Florida State University, he tested
the visual and problem-solving capacities of porpoises
above and below the water line. A summary of this work is
found in Kellogg and Rice (1966) and in Benjamin &
Bruce (1982, p. 475-478).
Robert Kohler (1922 - 2011): Obituary in the Tallahassee Democrat, October 30, 2011 (with highlighted section)
Robert Kohler, 88, of Tallahassee, Florida, passed away on Friday, 0ctober 28, 2011. Born October 31, 1922, in Milwaukee, Wisconsin, to Robert Urban Kohler and Helen Schlumn Kohler.
He moved to Midway, Florida in 1936, and graduated from Shanks High School. Robert voluntarily enlisted in the Army 1942, serving in the Air Corps as a Radar Repairman during WWII, then in Japan as part of the reconstruction. Upon return to Tallahassee, he enrolled at the Florida State College for Women (summer enrollment allowed for male students), joined the opening class of the Tallahassee Branch of the University of Floirida as a student at Florida State University when it became coed. He completed both Bachelor's and Master's degrees in Physics at FSU. He met his future wife, Marie Aiken, at FSU, and they were wed on January 28, 1950 in Tallahassee.
Robert worked as an Electronics Engineer at FSU, designing and installing equipment for many departments. Of these, he most enjoyed his work with Winthrop Kellogg, PhD, developing the equipment for the original research on echolocation in porpoises. He designed and built three early Tallahassee radio stations, including the first WFSU AM and FM stations, where he was also the first disc jockey. In addition, Robert along with Bill Ragsdale ("Willie the weatherman") designed and built WFSU-TV. He also worked at WTAL as an engineer and disc jockey. He became the Radiation Safety Officer at FSU, then worked for the FSU extension programs teaching Civil Defense and Disaster Preparedness to county personnel throughout the state. Finally, he worked for the State of Florida in Disaster Planning and nuclear power plant safety. He was known for his ability to find creative solutions to problems, and his ability to make needed equipment out of found materials, recycling and re-purposing before those words were in the dictionary. Robert was constantly being asked to fix equipment for many people, including the late Ruby Diamond, who engaged him to keep her music boxes working, and the Tallahassee Regional Airport, where he was called upon to repair the radar and air traffic control communications systems at many odd hours for years. He enjoyed what his family called "tinkering", fixing clocks, musical instruments, and electronic equipment of all kinds.
Robert was an active member of the Tallahassee Elks Lodge 937 for many years, serving as Tiler from 1990 until his death. He enjoyed traditional Jazz music, and collected a large number of recordings over the years. He is survived by his wife of 62 years, Marie Aiken Kohler, his children, James Kohler, Lisa Jernigan (Doug), and Lori Kohler, grandchildren (who called him "Oompah") Emily Kohler, Samuel Rozar, Leah Rozar, Sara Rozar, and Robert Kohler, as well as Ruth Kohler, plus many friends from his work days and the Elks Club.
He was predeceased by his brothers, James Kohler and Gerald Kohler.
A memorial service will be held on his birthday, Monday, October 31, 2011, 4 pm, at the Tallahassee Elks Lodge, 276 N. Magnolia Drive.
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