Below you will find a link to an article discussing a protein discovered in birds' eyes called cryptochrome, which allows them to detect magnetic fields when no landmark is in view. This explains how they travel with such instantaneous organization. The heart of the question I was interested in lies in the latter portion of Ed Young's article. I have pasted it in below the link to the full article. The connections between light, cryptochrome and a magnetic sense were laid out by Klaus Schulten and Thorsten Ritz in 2000, in a bravura paper that united biology and quantum physics.
http://blogs.discovermagazine.com/notrocketscience/2011/06/21/humans-have-a-magnetic-sensor-in-our-eyes-but-can-we-see-magnetic-fields/#.UsSyxCjTLlI
Can humans sense magnetic fields?
The current consensus is that humans cannot sense magnetic fields. Birds can do it, as can bats, turtles, ants, mole rats, sharks, rays, and more. Recently, Czech scientists have suggested that foxes, cows and deer also have the same ability. But look at all the recent reviews in this field, and you’ll see very little mention of our own species. A decade ago, a German group showed that our vision is slightly more sensitive in some directions than in others, but the results have not caught on.
It wasn’t always like this. In the 1980s, Robin Baker from the University of Manchester carried out a series of experiments which seemed to show that humans could sense magnetic fields. He took busloads of blindfolded volunteers on winding journeys for several kilometres before asking them to point their way back home. They did so more often than expected, and if they wore magnets on their heads, their accuracy dropped.
The results were published in Science and you can read Baker’s own description of his study in this 1980 issue of New Scientist. He even wrote a book about it. At the time, Baker said, “Whatever the repercussions, we have no alternative but to take seriously the possibility that Man has a magnetic sense of direction.”
Unfortunately, the main repercussion was a fierce series of rebuttals. Over the next decade, several groups around the world failed to repeat Baker’s results, even though Baker himself had no problems in doing so. He argued that their failure could have been due to local magnetic anomalies or brief changes in the strength of the magnetic field due to solar activity.
An American duo – Gould and Able – charitably suggested that Baker’s British students “either had cues available to them which were absent in our experiments, or are dramatically better than Americans in using whatever cues may be involved.” Max Westby and Karen Partridge, who failed to replicate Baker’s results in Sheffield, were less kind. “Perhaps it depends on which side of the Pennine Hills the experiments are conducted?” they asked. “It is obviously extremely difficult to counter all conceivable explanations for a negative result but we are forced to wonder about the ecological importance of a magnetic sense, the existence of which is so difficult to demonstrate.”
In the end, Baker relented and he moved on to the science of sperm. When I talked to him about the new study, he confesses that he hasn’t kept up with the field. “I’d spent nearly a decade, tested thousands of people under all sorts of conditions, and had absolutely no doubt. Then people did a few tests here and there and claimed the experiments didn’t replicate,” he says. “Even after I’d collected everybody else’s results and published that taken together, they did in fact constitute successful replication, nobody wanted to know. There was an element of ‘Sod them, then’.”
Reppert thinks that Baker’s story was an unfortunate one, especially since he stopped just when others were starting to discover light-based magnetic sensors. “I think Baker’s work was very good work but a lot of people had trouble reproducing aspects of it,” says Reppert. “It’s just very hard to do these sorts of behavioural experiments in humans.”
My thoughts are that magnetic sensing is connected to a more primitive instinctual state.
http://blogs.discovermagazine.com/notrocketscience/2011/06/21/humans-have-a-magnetic-sensor-in-our-eyes-but-can-we-see-magnetic-fields/#.UsSyxCjTLlI
Can humans sense magnetic fields?
The current consensus is that humans cannot sense magnetic fields. Birds can do it, as can bats, turtles, ants, mole rats, sharks, rays, and more. Recently, Czech scientists have suggested that foxes, cows and deer also have the same ability. But look at all the recent reviews in this field, and you’ll see very little mention of our own species. A decade ago, a German group showed that our vision is slightly more sensitive in some directions than in others, but the results have not caught on.
It wasn’t always like this. In the 1980s, Robin Baker from the University of Manchester carried out a series of experiments which seemed to show that humans could sense magnetic fields. He took busloads of blindfolded volunteers on winding journeys for several kilometres before asking them to point their way back home. They did so more often than expected, and if they wore magnets on their heads, their accuracy dropped.
The results were published in Science and you can read Baker’s own description of his study in this 1980 issue of New Scientist. He even wrote a book about it. At the time, Baker said, “Whatever the repercussions, we have no alternative but to take seriously the possibility that Man has a magnetic sense of direction.”
Unfortunately, the main repercussion was a fierce series of rebuttals. Over the next decade, several groups around the world failed to repeat Baker’s results, even though Baker himself had no problems in doing so. He argued that their failure could have been due to local magnetic anomalies or brief changes in the strength of the magnetic field due to solar activity.
An American duo – Gould and Able – charitably suggested that Baker’s British students “either had cues available to them which were absent in our experiments, or are dramatically better than Americans in using whatever cues may be involved.” Max Westby and Karen Partridge, who failed to replicate Baker’s results in Sheffield, were less kind. “Perhaps it depends on which side of the Pennine Hills the experiments are conducted?” they asked. “It is obviously extremely difficult to counter all conceivable explanations for a negative result but we are forced to wonder about the ecological importance of a magnetic sense, the existence of which is so difficult to demonstrate.”
In the end, Baker relented and he moved on to the science of sperm. When I talked to him about the new study, he confesses that he hasn’t kept up with the field. “I’d spent nearly a decade, tested thousands of people under all sorts of conditions, and had absolutely no doubt. Then people did a few tests here and there and claimed the experiments didn’t replicate,” he says. “Even after I’d collected everybody else’s results and published that taken together, they did in fact constitute successful replication, nobody wanted to know. There was an element of ‘Sod them, then’.”
Reppert thinks that Baker’s story was an unfortunate one, especially since he stopped just when others were starting to discover light-based magnetic sensors. “I think Baker’s work was very good work but a lot of people had trouble reproducing aspects of it,” says Reppert. “It’s just very hard to do these sorts of behavioural experiments in humans.”
My thoughts are that magnetic sensing is connected to a more primitive instinctual state.
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