On 17/05/2007, at 2:39 PM, Evan Beaver wrote:
Luckily for the bats they operate at quite different frequencies:
Radar 3MHz-110GHz
Bats Hearing 14KHz (humans stop at about 20KHz) through to 100KHz
Also radar is EM (Electromagnetic) energy, and sonar (sound) is
physical vibration of air (or water or other physical substance).
Radar operates in space. Sonar cannot.
Do any birds use Echolocation or have ridiculously high frequency
hearing?
I thought I read somewhere that Barn Owls use "passive sonar" (i.e.
they listen) to detect prey even in complete blackness. Also Gisela
Kaplan in her book about Magpies said they also listen for prey.
I will point out that submarines tend to use passive sonar except in
"attack" mode (as its more stealthy to listen rather than to echo
locate because your enemy can always listen for your emissions). I
wonder if any prey species of bats have ever developed this method of
protection?
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