The auditory filter shape of delphinid odontocetes was previously considered to be typically mammalian constant-quality in which filter bandwidths increase proportionally with frequency. Recent studies with porpoises demonstrate constant-bandwidth portions of the auditory filter. The critical ratios for a bottlenose dolphin were measured between 40 and 120 kHz by behaviorally determining the subject’s ability to detect pure tones in the presence of white noise. Critical ratios as a function of frequency were constant, indicating the auditory filter acts as a constant-bandwidth system in this frequency range. Re-analysis of past studies supports these findings, and suggests the delphinid auditory system is best characterized as a constant-Q system below 40 kHz and a constant-bandwidth-like system between 40 kHz and 120 kHz before returning to a constant Q pattern at the highest frequencies.

1.
Amundin
,
M.
(
1991
). “
Click repetition rate patterns in communicative sounds from the harbour porpoise, Phocoena phocoena
,” in
Sound Production in Odontocetes with Emphasis on the Harbour porpoise, Phocoena phocoena
(
Swede AB
,
Stockholm
), pp.
128
.
2.
Aroyan
,
J. L.
(
2001
). “
Three-dimensional modeling of hearing in Delphinus delphis
,”
J. Acoust. Soc. Am.
110
,
3305
3318
.
3.
Au
,
W. W. L.
(
1993
).
The Sonar of Dolphins
(
Springer
,
New York
), pp.
77
94
.
4.
Au
,
W. W. L.
,
Floyd
,
R. W.
,
Penner
,
R. H.
, and
Murchison
,
A. E.
(
1974
). “
Measurement of echolocation signals of the Atlantic bottlenose dolphin, Tursiops truncatus (Montagu), in open waters
,”
J. Acoust. Soc. Am.
56
,
1280
1290
.
5.
Au
,
W. W.
, and
Moore
,
P. W. B.
(
1990
). “
Critical ratio and critical bandwidth for the Atlantic Bottle-Nosed Dolphin
,”
J. Acoust. Soc. Am.
83
,
1635
1638
.
6.
Au
,
W. W. L.
,
Moore
,
P. W. B.
, and
Pawloski
,
D. A.
(
1988
). “
Detection of complex echoes in noise by an echolocating dolphin
,”
J. Acoust. Soc. Am.
83
,
662
668
.
7.
Au
,
W. L.
, and
Pawloski
,
D. A.
(
1990
). “
Cylinder wall thickness difference discrimination by an echolocating dolphin
,”
J. Acoust. Soc. Am.
88
,
S4
S5
.
8.
Au
,
W. W. L.
,
Pawloski
,
J. L.
, and
Nachtigall
,
P. E.
(
1995
). “
Echolocation signals and transmission beam pattern of a false killer whale (Pseudorca crassidens)
,”
J. Acoust. Soc. Am.
98
,
51
59
.
9.
Au
,
W. W. L.
,
Penner
,
R. H.
, and
Turl
,
C. W.
(
1987
). “
Propagation of beluga echolocation signals
,”
J. Acoust. Soc. Am.
82
,
807
813
.
10.
Cody
,
A. R.
, and
Russel
,
I. J.
(
1987
). “
The response of hair cells in the basil turn of the guinea-pig cohclea to tones
,”
J. Physiol.
383
,
551
569
.
11.
Diercks
,
K. J.
,
Trochta
,
R. T.
,
Greenlaw
,
C. F.
,
Evans
,
W. E.
(
1971
). “
Recording and analysis of dolphin echolocation signals
,”
J. Acoust. Soc. Am.
49
,
1729
1732
.
12.
Dooling
,
R. J.
, and
Saunders
,
J. C.
(
1975
). “
Hearing in the parakeet (Melopsittacus undulatus): Absolute thresholds, critical ratios, frequency difference limens, and vocalizations
,”
J. Comp. Physiol. Psychol.
88
,
1
20
.
13.
Fletcher
,
H.
(
1940
). “
Auditory patterns
,”
Rev. Mod. Phys.
12
,
47
65
.
14.
Gellermann
,
L. W.
(
1933
). “
Chance orders of alternating stimuli in visual discrimination experiments
,”
J. Genet. Psychol.
42
,
206
208
.
15.
Hansen
,
M.
,
Wahlberg
,
M.
, and
Madsen
,
P. T.
(
2008
). “
Low-frequency components in harbor porpoise (Phocoena phocoena) clicks: Communication signal, by-products, or artifacts?
J. Acoust. Soc. Am.
124
,
4059
4068
.
16.
Herman
,
L. M.
, and
Tavolga
,
W. N.
(
1980
). “
The communication systems of cetaceans
,” in
Cetacean Behaviour
, edited by
L. M.
Herman
(
Wiley Interscience
,
New York
), pp.
149
209
.
17.
Ibsen
,
S. D.
,
Au
,
W. W. L.
,
Nachtigall
,
P. E.
, and
Breese
,
M.
(
2009
). “
Functional bandwidth of an echolocating Atlantic bottlenose dolphin (Tursiops truncatus)
,”
J. Acoust. Soc. Am.
125
,
1214
1221
.
18.
Johnson
,
C. S.
(
1968
). “
Masked tonal thresholds in the bottlenosed porpoise
,”
J. Acoust. Soc. Am.
44
(
4
),
965
967
.
19.
Johnson
,
C. S.
,
McManus
,
M. W.
, and
Skaar
,
D.
(
1989
). “
Masked tonal hearing thresholds in the beluga whale
,”
J. Acoust. Soc. Am.
85
(
6
),
2651
2654
.
20.
Kamminga
,
C.
, and
Wiersma
,
H.
(
1981
). “
Investigations on cetacean sonar II. Acoustical similarities and differences in odontocete sonar signals
,”
Aquat. Mamm.
8
,
41
61
.
21.
Kastelein
,
R. A.
,
Bunskoek
,
P.
,
Hagedoorn
,
M.
,
Au
,
W. W. L.
, and
de Haan
,
D.
(
2002
). “
Audiogram of a harbor porpoise (Phocoena phocoena) measured with narrow-band frequency-modulated signals
,”
J. Acoust. Soc. Am.
112
,
334
344
.
22.
Kastelein
,
R. A.
,
Wensveen
,
P. J.
,
Hoek
,
L.
,
Au
,
W. W. L.
,
Terhune
,
J. M.
, and
de Jong
,
C. A. F.
(
2009
). “
Critical ratios in harbor porpoises (Phocoena phocoena) for tonal signals between 0.315 and 150 kHz in random Gaussian white noise
,”
J. Acoust. Soc. Am.
126
,
1588
1597
.
23.
Ketten
,
D.
, and
Wartzok
,
D.
(
1990
). “
Three-dimensional reconstructions of the dolphin ear
,” in
Sensory Abilities of Cetaceans
, edited by
J.
Thomas
and
R.
Kastelein
(
Plenum Press
,
New York
), pp.
81
105
.
24.
Kiang
,
N. Y.
,
Watanabe
,
T.
,
Thomas
,
E. C.
, and
Clark
,
L. F.
(
1962
). “
Stimulus coding in the cat’s auditory nerve
,”
Ann. Otol. Rhinol. Laryngol.
71
,
1009
1026
.
25.
Lammers
,
M. O.
,
Au
,
W. W. L.
, and
Herzing
,
D. L.
(
2003
). “
The broadband social acoustic signaling behavior of spinner and spotted dolphins
,”
J. Acoust. Soc. Am.
114
,
1629
1639
.
26.
Long
,
G. R.
(
1977
). “
Masked auditory thresholds from the bat, Rhinolophus ferrumequinum
,”
J. Comp. Physiol.
116
,
247
255
.
27.
Mellen
,
R. H.
(
1952
). “
The thermal-noise limit in the detection of underwater acoustic signals
,”
J. Acoust. Soc. Am.
24
,
478
480
.
28.
Mohl
,
B.
, and
Andersen
,
S.
(
1973
). “
Echolocation-high-frequency component in click of a harbor porpoise (Phocoena-Ph. L.)
,”
J. Acoust. Soc. Am.
54
,
1368
1372
.
29.
Moore
,
P. W. B.
,
Hall
,
R. W.
,
Friedl
,
W. A.
, and
Nachtigall
,
P. E.
(
1984
). “
The critical interval in dolphin echolocation: What is it?
,”
J. Acoust. Soc. Am.
76
,
314
317
.
30.
Moore
,
P. W. B.
,
Pawloski
,
D. A.
, and
Dankiewicz
,
L.
(
1995
). “
Interaural time and intensity difference thresholds in the bottlenose dolphin (Tursiops truncatus)
,” in
Sensory Systems of Aquatic Mammals
, edited by
R. A.
Kastelein
,
J. A.
Thomas
, and
P. E.
Nachtigall
(
DeSpil
,
Woerden, Netherlands
), pp.
11
23
.
31.
Moss
,
C. F.
, and
Simmons
,
A. M.
(
1986
). “
Frequency selectivity of hearing in the green treefrog, Hyla cinerea
,”
J. Comp. Physiol. A.
159
,
257
266
.
32.
Nachtigall
,
P. E.
(
1980
). “
Odontocete echolocation performance on object size, shape and material
,” in
Animal Sonar Systems
, edited by
R. G.
Busnel
and
J. F.
Fish
(
Plenum Press
,
New York
), pp.
71
95
.
33.
Nachtigall
,
P. E.
,
Au
,
W. W. L.
,
Pawloski
,
J.
, and
Moore
,
P. W. B.
(
1995
). “
Risso’s dolphin (Grampus griseus) hearing thresholds in Kaneohe Bay, Hawaii
,” in
Sensory Systems of Aquatic Mammals
, edited by
R.
Kastelein
,
J.
Thomas
, and
P.
Nachtigall
(
DeSpil
,
Woerden, Netherlands
), pp.
49
53
.
34.
Nachtigall
,
P. E.
,
Mooney
,
T. A.
,
Taylor
,
K. A.
,
Miller
,
L. A.
,
Rasmussen
,
M. H.
,
Akamatsu
,
T.
,
Teilmann
,
J.
,
Linnenschmidt
,
M.
, and
Vikingsson
,
G. A.
(
2008
). “
Shipboard measurements of the hearing of white-beaked dolphin Lagenorhynchus albirostris
,”
J. Exp. Bio.
211
,
642
647
.
35.
Palmer
,
A. R.
, and
Russel
,
I. J.
(
1986
). “
Phase-locking on the cochlear nerve of the guinea-pig and its relation to the receptor potential of inner hair-cells
,”
Hear. Res.
24
,
1
15
.
36.
Patterson
,
R. D.
, and
Moore
,
B. C. J.
(
1986
). “
Auditory filters and excitation patters and representations of frequency resolution
,” in
Frequency Selectivity in Hearing
, edited by
B. C. J.
Moore
(
Academic
,
London
), pp.
123
177
.
37.
Popov
,
V. V.
,
Supin
,
A. Y.
,
Wang
,
D.
, and
Wang
,
K.
(
2006
). “
Nonconstant quality of auditory filters in the porpoises, Phocoena phocoena and Neophocaena phocaenoides
,”
J. Acoust. Soc. Am.
119
,
3173
3180
.
38.
Robinson
,
D.
, and
Watson
,
C.
(
1973
). “
Phychophysical methods in modern phychoacoustics
,” in
Foundations of Moderm Auditory Theory
, edited by
J. V.
Tobias
(
Academic Press
,
New York
), pp.
99
131
.
39.
Schusterman
,
R.
(
1980
). “
Behavioral methodology in echolocation by marine mammals
” in
Animal Sonar Systems
, edited by
R.
Busnel
and
J.
Fish
(
Plenum Press
,
New York
), pp.
11
41
.
40.
Shailer
,
M. J.
,
Moore
,
B. C. J.
,
Glasberg
,
B. R.
,
Watson
,
N.
, and
Harris
,
S.
(
1990
). “
Auditory filter shapes at 8 and 10 kHz
,”
J. Acoust. Soc. Am.
88
,
141
148
.
41.
Thomas
,
J. J.
,
Pawloski
,
J.
, and
Au
,
W. W. L.
(
1990
). “
Masked hearing abilities in a false killer whale (Pseudorca crassidens)
,” in
Sensory Abilities of Cetaceans
, edited by
J.
Thomas
and
R. A.
Kastelein
(
Plenum
,
New York
), pp.
395
404
.
42.
Thomas
,
J. A.
, and
Turl
,
C.W.
(
1990
). “
Echolocation characteristics and range detection by a false killer whale (Pseudorca crassidens)
,” in
Sensory Abilities of Cetaceans
, edited by
J.
Thomas
and
R. A.
Kastelein
(
Plenum
,
New York
), pp.
321
334
.
43.
Viemeister
,
N. F.
, and
Plack
,
C. J.
(
1993
). “
Time Analysis
,” in
Human Psychophysics
, edited by
W. A.
Yost
,
A. N.
Popper
, and
R. R.
Fay
(
Springer-Verlag
,
New York
), pp.
116
154
.
44.
Wang
,
D.
,
Wursig
,
B.
, and
Evans
,
W.
(
1995
). “
Comparisons of whistles among seven odontocetes species
,” in
Sensory Systems of Aquatic Mammals
, edited by
R. A.
Kastelein
,
J. A.
Thomas
, and
P. E.
Nachtigall
(
DeSpil
,
Woerden, Netherlands
), pp.
299
323
.
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