A bat's ability to hone in on very small objects, such as insects, is amazing. In a paper recently published in Science there is evidence that bats are not only excellent at hunting this way, but the Mexican free-tailed bat is also able to thwart their competition from catching their food through sound. These bats "jam" another bat's echolocation so that they are 85.9% less likely to catch their prey. When a hunting bat is approaching its prey the echos become more frequent, creating what is referred to as the "feeding buzz". If another bat detects this feeding buzz, it emits very quick clicking sounds that "jam" the hunting bat's signal, thus causing it to just barely miss its prey.
It is thought that this must improve the signal jammer's ability to catch more food, but this has yet to be tested. Thus far the Mexican free-tailed bat is the only bat known to do this.
The use of echolocation and the ability to pinpoint such small objects is incredible. In addition to creatures in the animal world using this tactic it was recently determined that blind people may have the ability to use a form of echolocation to navigate as well. Researchers from the University of Southampton's Institute of Sound and Vibration Research (UK) and the University of Cyprus completed studies with blind and sighted test subjects to see how they could navigate using echos and clicks. This phenomena does not necessarily have to do with lack of sight, it involves the quality of one's hearing as well. National Geographic's Brain Games recently explored this phenomena as well. See it in action here. Pretty awesome! It makes you wonder how many other things humans and animals are capable of that have yet to be discovered.
Science Daily: Echolocation: Blind people have the potential to use their "inner bat" to locate objects, study finds (Many great related articles on this link as well!)
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