One of the most creative uses of those fantastic satellite images from Google Earth comes from the most unlikely of places. Sabine Begall
, a zoologist at the University of Duisberg-Essen, along with a few of her collaborators, carried out some painstaking measurements of the alignment of cattle in farmers' fields. They discovered some remarkable things. For one, they found a significant tendency for cattle to align themselves in the north-south direction
. Because even the powerful satellite images used by Google did not have sufficient resolution to distinguish head from tail, the investigators were not able to say whether the animals faced north or south, but the data are otherwise convincing, and some recent counter-claims
that Begall’s group may have committed some sampling errors seem to have been quelled
for the time being. Equally interesting was the group’s claim that cattle grazing in the vicinity of high-tension power lines did not show north-south orientation
, suggesting that the extremely low-frequency magnetic fields emitted by such lines may have disrupted the natural orientation of the cattle.
The idea that magnetic fields can be used for orientation is not new. It’s been known for some time that a wide range of animals—from bacteria to birds—use magnetic fields to find their way from place to place. But solid demonstrations of magnetic field sensitivity in mammals is less common. There have been some studies of preferences for nesting sites in a variety of rodents, and there is the remarkable story of the naked mole rat, a burrowing rodent with poor eyesight that appears to find its way through subterranean tunnels using its sensitivity to magnetic fields.
But in the case of ruminating animals (and I love the image evoked by that phrase, by the way, of cows gently nuzzling the grass while they struggle with a difficult paragraph from Wittgenstein’s Philosophical Investigations), what is the point of aligning themselves with the Earth’s axes? In a recent review, Begall’s group speculate that one advantage to such alignment may be that it helps them pay attention! Supposing that information from other senses such as hearing and vision are competing for brain processing time with whatever form the processing of magnetic information might take, they suggest that a north-south alignment may be the best position for quelling cross-talk between different senses. It’s also possible, given that some evidence suggests that the magnetic sense resides in the eye, that magnetic alignment increases the sensitivity of the visual system, albeit ever so slightly.
What about us? There’s a fantastically interesting history to the scientific exploration of the magnetic sense in human beings. British biologist, Robin Baker, conducted a series of controversial experiments designed to determine whether human beings used the magnetic sense to navigate. In some of his experiments, he had blindfolded research participants driven by bus on long, meandering rides through the countryside following which they were asked to point toward home. Baker reported significant differences between groups of participants who had been asked to wear magnets on their heads and those who had not. Baker’s experiments were met with skepticism, and others were unable to replicate Baker’s findings (though Baker insisted to the end of the debate that these researchers had failed to correctly duplicate either his methodology or his analytical procedures). Eventually, Baker turned his attention to other issues (the kamikaze sperm hypothesis, for one!), and, frustrated by changes he saw in the British university system, he ultimately gave up research to live in the south of Spain, where he continues to write.
More recent studies, though, have produced some tantalizing suggestions that magnetic fields may influence certain subtle aspects of human behaviour and physiology. One study has shown that the latency to REM sleep onset is shorter in those lying in the east-west direction than in those lying in the north-south direction. A handful of other experiments have shown that some properties of human brainwaves vary depending on the orientation of the participant. One study, for example, showed that alpha waves, which are characteristic of quiet relaxation, seem to constitute a stronger component of the EEG in participants who are facing east or west as compared to those facing north or south.
As a psychologist interested in architectural design, I pay attention to the ongoing discussion about the application of ancient practices such as feng shui and vastu shastra to the design of structures, and I’ll have more to say about this in a later post. In some of the practices of these traditions, I see faint echoes of the principles laid out by architects working from rather different starting points (Christopher Alexander, for one), and this connection interests me a great deal. But I’ve never paid as close attention to the parts of these traditions that prescribe how a building should be laid out with respect to the cardinal directions of the planet. Now, given recent findings on magnetic alignment in animals and the very faint rumble that we, too, may have some sensitivities to the Earth’s magnetic fields, I’m wondering just a little about this. Even if the effects of these fields were exquisitely subtle, is it possible that, over the course of very long exposures, they could exert an effect on our fortunes?
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