Audiogram of the blind mole rat (Spalax ehrenbergi)
Data from: Heffner, R.S., and Heffner, H.E. (1992) Hearing and sound localization in blind mole rats, Spalax ehrenbergi. Hearing Research, 62, 206-216.
Absolute thresholds (in dB re 20 µN/m2) for two blind mole rats
(designated A and B)
|
Frequency (in kHz) |
Individual Thresholds (in dB) |
Average |
|
|
A |
B |
||
|
.008 |
94 |
92 |
93 |
|
.016 |
76 |
81 |
78.5 |
|
.0315 |
73 |
75 |
74 |
|
.063 |
54 |
57 |
55.5 |
|
.125 |
52 |
50 |
51 |
|
.250 |
41 |
43 |
42 |
|
.500 |
40 |
41 |
40.4 |
|
.800 |
31 |
32 |
31.5 |
|
1.6 |
44 |
45 |
44.5 |
|
4 |
57 |
46 |
51.5 |
|
8 |
74 |
60 |
67 |
|
11.2 |
87 |
87 |
87 |
Lowest and highest frequencies audible at sound
pressure levels (SPL) ranging from 30 to 70 dB SPL
|
SPL (in dB) |
Lowest audible frequency (in kHz) |
Highest audible frequency (in kHz) |
|
70 |
.037 |
8.2 |
|
60 |
.052 |
5.9 |
|
50 |
.135 |
3.4 |
|
40 |
.520 |
1.6 |
|
30 |
~.800 |
~.800 |
Additional Parameters:
Body weight = 140 g
Functional interaural distance= 87 µs
(Time required for sound to travel around the head from one auditory meatus to the other.)
Comments: Threshold values taken from original data. For another audiogram, see Bronchti, G., Heil, P., Scheich, H., and Wollberg, Z. (1989) Auditory pathway and auditory activation of primary visual targets in the blind mole rat (Spalax ehrenbergi): I.2-deoxyglucose study of subcortical centers. Journal of Comparative Neurology, 284, 253-274.