Bob Crantz wrote:

Joe,


However, there are piles of dead birds to be found at the poles. Birds, and
other animals, have small bits of paramagnetic material in their skulls that
help with direction finding. Once they get near the poles they try to fly
straight up and eventually fall to the ground from exhaustion.

You have a wonderfully inventive imagination!

An even bigger problem is GPS navigation near the true poles. To a GPS unit
all direction is lost at the pole.

Why would this be? I don't see why the location algorithym should become
invalid at these locations.

Cheers
Marty