TABLE 2.

	Chinchilla	Human	Rabbit	Cat
State of ear	Cochlea Drained (Fig 13A)	No Incus (Fig 13B)	IS-Joint Interrupted (Fig 13C)	Cochlea Drained (Fig 13F)
CTO, Acoustic Compliance of TM and Ossicles (m3/Pa)	1.11×10−10	1.11×10−11	1.75×10−12	6.37×10−12
Equivalent Volume (cc)	12.3	1.56	0.25	0.89
First resonance (Hz)	300	620	2000	1300
MTO, Acoustic Mass of TM and Ossicles MTO =(CTO ω2)−1 (kg-m−4)	3215	5915	3617	2354
ATM, pars tensa Area* (mm2)	70	60	20	36
mTO, ‘Effective’ Mechanical Mass mTO= MTO ATM2 (mg)	15.75	21.29	1.45	3.05
Mass of TM† (mg)	(16.3)	14	(4.7)	(8.4)
Mass of ossicles †† (mg)	11.5	54.5	4.3	15.1
Total mass of TM and ossicles (mg)	27.8	68.5	9.0	23.5

Estimates of the acoustic compliance, acoustic mass and resonant frequency of the TM and ossicles in four species based on the data of Figure 13. These data allow computations of the ‘Effective’ mechanical mass of the TM and ossicles that is compared to published mass measurements.

^*From Rosowski (1994)

^†Mass of the human TM is from Wever & Lawrence (1954). The mass of the TM of the other animals is computed by scaling the human TM mass by the ratio of the TM areas of the other animals to the human TM area.

^††From Nummela (1995)