Re: echolocating bats-how do they know what they hear is their echo?

All insectivorous bat species echolocate.

Each species produces a limited range of ultrasound frequencies. For example, Hipposideros speoris emits a frequency of about 135 kilohertz, Hipposideros bicolor emits in a range close to 150 kilohertz, and another related species of Hipposideros atter emits a frequency of about 200 kilohertz.

During echolocation, each outgoing call is registered in the brain so that the echo can be compared to the original sound.

When more than one bat belonging to the same species forage in the same area, they avoid "jamming" of their ultrasound frequency in a simple and clever way - each bat fine tunes its emission frequency and specifically 'listens' for the Doppler shifted echoes of that frequency.