Homing Pigeons
"Numerous experiments on homing have already been carried out with pigeons. Nevertheless, after nearly a century of dedicated but frustrating research, no one knows how pigeons home, and all attempts to explain their navigational ability in terms of known senses and physical forces have so far proved unsuccessful. Researchers in this field readily admit the problem. 'The amazing flexibility of homing and migrating birds has been a puzzle for years. Remove cue after cue, and yet animals still retain some backup strategy for establishing flight direction.' 'The problem of navigation remains essentially unsolved.'
The inertial navigation hypothesis [that pigeons 'register the twists and turns of the outward journey'] can...be ruled out, and is no longer seriously entertained by researchers in the field.
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I propose that the sense of direction of homing pigeons depends on something rather like an invisible elastic band connecting them to their home, and drawing them back toward it. When they are taken away, this band is stretched. If on their return flight they overshoot their home, as some of the pigeons flying with frosted-glass contact lenses did, this connection serves to pull them back again.
Source
Not so, Rupe. Pigeons don't use "morphic fields" when they navigate. They follow the roads.
Researchers have cracked the puzzle of how pigeons find their way home: they just follow the main roads.
Zoologists now believe the phrase "as the crow flies" no longer means the shortest most direct route between two points. They say it is likely that crows and other diurnal birds also choose AA-suggested routes, even though it makes their journeys longer.
Some pigeons stick so rigidly to the roads that they even fly round roundabouts before choosing the exit to lead them back to their lofts.
Source: Daily Telegraph (requires free registration)
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