Re: Aquatic ape theory

Bill Burnett (bbur@wpo.nerc.ac.uk)
Wed, 4 Oct 1995 13:07:45

In article <44o6lj$e86@nntp.ucs.ubc.ca> VINCENT@REG.TRIUMF.CA (pete) writes:

>Hmm, I don't know why you would say this. Any creature's hearing
>is much better under water, because of the way sound travels
>through water. I've never noticed any difficulty hearing and
>locating sounds underwater. And I can hear a power boat long
>before it sounds above water. The sound is often so clear
>that I'm fooled into thinking a boat is close approaching
>when it turns out to be still half a mile away. Sounds generated
>in the air, particularly high above sea level, are sometimes
>attenuated when they refract into the water, and of course
>near a beach, the surf can mask a lot of sounds, but in general
>no, my hearing is not impaired underwater at all.

Are you SURE you can LOCATE sounds easily? Speaking as a dedicated
recreational scuba and free diver, I certainly can't locate sounds
underwater, and I'm not unusual in this regard, most people can't. Sure, I
can hear them, but direction finding is very difficult... this is supposedly a
consequence of sound travelling much faster through water hence the time
differential between sounds reaching either ear is insufficient for a stereo
image (or so I'm told...) One of the most uncomfortable feelings you can have
is surfacing after a long breath hold dive, hearing a boat on the surface and
not knowing where it is or how far away... but you gotta come up or grow
gills... Similarly, if someone tries to attract your attention by banging on
their scuba tank everyone I know looks the wrong way and takes a while to find
you and enable visual communication... And if you consider the problems some
people have in equalising the pressure in their ears while diving I think we
can safely say that TODAY'S human ear is NOT adapted for diving... (I make
no claims for a supposed AA ear.)

B.