## Object features extracted by an echolocating dolphin from acoustic echoes: computational models and behavioral data

Gennadi Zaslavski

University authority for applied research,

RAMOT, Tel-Aviv University, Israel

gennadi.zaslavski@gmail.com

Theoretical time resolution of the bottlenose dolphin echolocation clicks is as high as 15 -20 microseconds. Given a very broad frequency range of the bottlenose dolphin hearing extending from 5-10 kHz to as far as 130-135 kHz the dolphin sonar time resolution could be as high as the theoretical time resolution of the echolocation clicks. Multi-highlight structure of a target echo in response to brief echolocation clicks results in the echo frequency spectrum being rippled, with local maxima and minima at different frequencies. There are many computer simulated models of echo-processing in dolphins. Most of these models are based on the frequency domain analysis of target echoes although the time domain features of an echo are normally more conspicuous than the frequency domain features. As long as an actual time resolution of the dolphin sonar is not known it is impossible to choose between the frequency and time domain analysis. In this presentation I discuss some data we obtained in behavioral experiments with bottlenose dolphins indicating the auditory time resolution as high as around 20 microseconds which is the theoretical time resolution of the bottlenose dolphin echolocation clicks. With this high auditory time resolution bottlenose dolphins appear capable of extracting the time domain features of echoes from most of real targets and phantom echoes tested in numerous behavioral experiments.