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From: kell@cs.albany.edu (Brian A. Kell)
Newsgroups: sci.skeptic,sci.bio
Subject: Re: Further Evolving Eyebrows
Message-ID: <241@karp.albany.edu>
Date: 5 Nov 90 17:01:20 GMT
References: <1371@cluster.cs.su.oz.au> <2431@anaxagoras.ils.nwu.edu> <1990Nov5.123912.15186@ioe.lon.ac.uk>
Followup-To: sci.bio
Organization: SUNY Albany, Comp Sci Dept, Albany, NY
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In article <1990Nov5.123912.15186@ioe.lon.ac.uk>, teexmmo@ioe.lon.ac.uk (Matthew Moore) writes:
> The Hardy-Morgan theory of human evolution (aka the aquatic theory)
> considers eyebrows to be sunshades. What do you do if the sun gets in
> your eyes? - You frown, or lower your eyebrows.

... and maybe shade your eyes with your hand?

My theory (although I'm no expert!) has always been that eyebrows make
really good rain gutters.  If you ever stand/walk/hike/jog/etc. in
the rain, you may notice that the raindrops hitting your forehead are neatly
diverted to the side by your eyebrows, allowing clearer vision than if
the water were dribbling into your eyes.  This seems to have an
obvious selective advantage for hunting and/or evading predators in
the days before umbrellas and windshield wipers.

----------------------------------------------------------------------------
Brian Kell 
SUNY/Albany Departments of Computer Science and Biological Sciences
brian@isadora.albany.edu
kell@cs.albany.edu
bk7295@albnyvms.bitnet