Re: High-frequency hearing in humans

[John Culling <cullingj@xxxxxxxxxxxxx>]

My understanding is that high-frequency hearing is basically
a mammal thing. Even the vaunted auditory system of the 
barn owl is limited to 10 kHz. The reason mammals developed
high frequency hearing is probably that they were small
and nocturnal and needed to hear where things were in
the dark with their small heads. Humans, of course only
go one octave into this exclusively mammalian sensory 
domain - we're big and don't go out nights so often these
days, so it's a bit vestigial.

Having emphasised the localisation angle, I wouldn't want
to suggest that communication is unimportant. I once heard
a demo of a rat being tickled and the sound, transformed by
a bat detector, was unmistakably giggling - they vocalise at
very high frequencies.

John.

On 25 Jan 2011 at 10:27, Piotr Majdak wrote:

> Dear list,
> 
> I'm looking for the reasons for the good high-frequency* hearing  in humans.
> 
> The reasons I have until now are actually the obvious ones:
> * Pinna localization cues
> * Interaural level cues (ILD, they actually start to work from around 2 kHz)
> 
> What do you think: if there were no need for the ILD and pinna cues, 
> would there be any other reasons?
> 
> Thanks,
> 
> Piotr
> *) say, above 8 kHz
> 
> -- 
> Piotr Majdak
> Psychoacoustics and Experimental Audiology
> Acoustics Research Institute <http://www.kfs.oeaw.ac.at>
> Austrian Academy of Sciences <http://www.oeaw.ac.at/>
> Wohllebengasse 12-14, 1040 Vienna, Austria
> Tel.: +43 1 51581-2511
> Fax: +43 1 51581-2530

Bob Masta
 
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