. >    From what I've read, I understand that bees orient themselves with
. > respect to the asimuth of the sun.  This brought up the question of what
. > do bees do on the equinoxes at local noon on the equator?  I don't see
. > how there could be any light polarization effect in this situation
. > either.
.
.
. The sun travels from east to west, and shadow can be measures at any
. time of the day. The sun azimuth plus a time will provide a direction.
 
   It's not quit clear to me that you understood the question.  Under
the condition I mentioned the sun has no azimuth.  It's like asking
what the longitude of the north pole is? Is the north pole east or
west of Greenwhich?  Also, there are no shadows, except directly under
overhanging objects.  The sun is directly overhead, 90 degrees up.
 
-Bruce