Audiogram of the fox squirrel (Sciurus niger)
Data from: Jackson, L., Heffner, H.E., and Heffner, R.S.(1997) Audiogram of the fox squirrel, (Sciurus niger). Journal of Comparative Psychology, 111, 100-104.
Absolute thresholds (in dB re 20 µN/m2) for two fox squirrels
(designated A and B)
|
Frequency (in kHz) |
Individual Thresholds (in dB) |
Average |
|
|
A |
B |
||
|
.063 |
81 |
78 |
79.5 |
|
.125 |
58 |
56 |
57 |
|
.250 |
29 |
32 |
30.5 |
|
.500 |
11 |
12.5 |
12 |
|
1 |
8 |
9 |
8.5 |
|
2 |
5 |
10.5 |
8 |
|
4 |
13 |
7 |
10 |
|
8 |
0 |
1.5 |
0.8 |
|
16 |
20 |
16 |
18 |
|
32 |
20 |
14 |
17 |
|
45 |
52 |
32 |
42 |
|
50 |
69 |
60 |
64.5 |
|
56 |
— |
85 |
85 |
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 |
.084 |
52 |
|
60 |
.113 |
49 |
|
50 |
.150 |
47 |
|
40 |
.195 |
44 |
|
30 |
.250 |
38 |
Additional Parameters:
Body weight = 750 g
Functional interaural distance= 155 µs
(Time required for sound to travel around the head from one auditory meatus to the other.)
Comments: Threshold values taken from original data.