Audiogram of the long-eared hedgehog (Hemiechinus auritus)
Data from: Ravizza, R.J., Heffner, H.E., and Masterton, B.(1969) Hearing in primitive mammals: II, Hedgehog (Hemiechinus auritus). Journal of Auditory Research, 9, 8-11.
Absolute thresholds (in dB re 20 µPa) for two hedgehogs
(designated A and B)
|
Frequency (in kHz) |
Individual Thresholds (in dB) |
Average |
|
|
A |
B |
||
|
.25 |
68 |
70 |
69 |
|
.5 |
63 |
63 |
63 |
|
1 |
46 |
49 |
48 |
|
2 |
31 |
31 |
31 |
|
4 |
19 |
8 |
14 |
|
8 |
9 |
-3 |
3 |
|
16 |
11 |
5 |
8 |
|
32 |
19 |
14 |
16 |
|
45 |
46 |
29 |
38 |
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 |
.25 |
— |
|
60 |
.52 |
— |
|
50 |
.88 |
56* |
|
40 |
1.35 |
52 |
|
30 |
2.1 |
40 |
*Extrapolated value
Additional Parameters:
Body weight = 500 g
Functional interaural distance = 167 µs
(Time required for sound to travel around the head from one auditory meatus to the other.)
Comments: Threshold values taken from original data.
An audiogram of the African hedgehog (Atelerix sp.) indicates that hedgehogs may not be as sensitive to low frequencies as indicated here (Koay, unpublished).