The middle ear of the Tokay Gecko

1. Amplitudes of middle ear structure were measured in Gekko gecko, using the Mössbauer effect. 2. The amplitude of the columella/extracolumella system is more or less constant up to 1 kHz and then falls off. 3. A frequency-dependent lever ratio exists between the inferior process on the drum and the columella. 4. Below 2 kHz the drum locations tested all had higher amplitudes than the inferior process. 5. The vibration pattern of the drum is simple below 3 kHz, but breaks into at least two peaks above this frequency. 6. The drum vibrates in phase at low frequencies, but at higher frequencies larger phase variations exist. 7. All the above factors contribute to highly efficient impedance matching at low frequencies, but poor matching above about 4 kHz. 8. The eardrum intensity response is linear at the intensities used.