FYI, you might want to check out following article at BBC's website
(http://news.bbc.co.uk/2/hi/science/nature/3629775.stm), summarizing a paper
in most recent issue of AAAS's "Science" journal on intriguing new research
findings about the navigational adaptability of migrating birds. Study
results tend "to confirm that birds can 'reset' their navigation systems
daily by comparing the direction of the sunset with the magnetic signals
they detect."

Bruce Moorhead
Port Angeles, WA
bruceb at olypen.com