|1.||The actual operation of the sound source and sonar beam generation is not understood. Measurements using velocity detectors instead of pressure transducers in the near-field would be helpful. Also, measuring changes in the shape of the nasal sacs might help clarify their role in sound production. When the "state of the art" is more advanced, pulse interference laser holography could be a powerful tool to study melon and other displacements during phonations.|
|2.||Experiments using human listeners and electronically transformed echoes are a useful method of studying echolocation and should be continued. The importance of target scanning needs to be determined.|
|3.||Floyd ( 1980) suggestion of using "electronic phantom" targets to test various theories is an extremely promising approach. In this type of experiment echoes are produced electronically and projected back to the dolphin in response to its own outgoing sonar pulses instead of using physical targets which simply reflect the outgoing signal. This approach allows the experimenter to check responses to specific changes in the echo.|
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