"Ultimate Reality and a Closer Look at Magnetoreception"

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Biology 202, Spring 2005
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"Ultimate Reality and a Closer Look at Magnetoreception"

Samantha Thomson

It's happened to everyone - when pulling into your driveway after a long car ride home you ask yourself, "how did I get here?" Unfortunately this is a wonderful question with a particularly unsettling answer: LUCK. There are endless speculations about reality, infinite testimonies of "unreal" events that contain no roots to the known, or plausible. "There are two levels of reality, said the Dalai Lama, referring to Buddhism's ordinarily perceived reality and the Ultimate Reality, where the mind stills to such a degree that everything appears in its true nature. Nothing is intrinsically real, he said. Things that appear to be real are so because of our perception, which solidifies them."(1)

It has been suggested that there are two qualities to every object: first, the primary quality is used to classify an object as being able to elicit a particular sensation. The secondary quality, however, is one's reaction to an object. For instance, the roads on which I drove to get back home existed because I assumed that one of their primary qualities included providing a direct route back to my house. There is, however, a problem when describing the secondary qualities of the road-if secondary qualities are defined as a particular reaction to an object (color, shape, size, etc.) then in the case of the roads I took on my drive home, do they retain no secondary qualities since I took no notice of my surroundings? (2) Furthermore, humans only have five common ways of interacting with their environments. So, how does one even begin to speculate about reality if we, as humans, lack particular sensory capabilities? Did the route home actually exist that night, or was it just an assumption I made about previous settings I had once experienced? Many animals, in particular species of birds and fish, display common behaviors in response to the Earth's magnetic field. This "sixth-sense" capability that is inaccessible to humans makes one doubt the reality of the world around us as we know it. Suddenly, given the possible existence of an infinite number of signals, the line distinguishing primary qualities from secondary qualities obtained by sensory organs fades into obscurity.

Extensive research has been conducted on the particular migration patterns of birds. Beginning in 1966 Wolfgang and Roswitha Wiltschko in Frankfurt, Germany designed numerous experiments to determine what effect magnetic fields have on particular species of birds. They conducted the experiments by placing the birds in funnel shaped cages surrounded by signal generator coils which produced oscillating magnetic fields. Then they recorded the side to which the birds migrated. The birds tended to assemble on the southern side of the cage during the fall season regardless of where "true south" was positioned (3)(4). The results were insightful and generated even more questions about physiological mechanisms, neurological integration, and the psychological impact this could have on human perception of "Ultimate Reality".

Scientists, to clarify the physical components of magnetoreception, performed follow-up research. Since the Earth produces an extremely weak magnetic field (only 0.5 Gauss), scientists knew that any proposed magnoreceptors must be capable of responding to miniscule fluctuations in exerted torque. Scientists at the University of California Irvine demonstrated through experimentation that the magnetic compass of birds is in fact light dependent. When test birds were exposed to short wavelengths of blue/green light, normal migration occurred; however, when those same birds were exposed to red light, no North-South orientation was observed (5)(6). This experiment along with many others opened new doors to the possibility of an integration of photo and magnetoreception. One necessary component for this hypothetical sensory receptor is a mechanism present in the nervous system which is able to distinguish ambient light from magnetic force fields; such an integrated mechanism is difficult for science to imagine - but then again I did make it home on a route which may not have existed.

Other experimentation was done to test the link between photo and magnoreception. Scientists attached magnets around the heads of pigeons. Results showed that the birds displayed normal migration on sunny days as the sun served as a guide. On cloudy days, however, the birds were unable to orient themselves (7). Though overwhelming evidence suggests that photoreceptors greatly play into magnoreception in birds, scientists knew that light dependence was not universal because other animals (such as Elasmobranches) are able to accurately migrate completely void of light (8).

By using magnetometers to detect materials within organisms that respond to weak magnetic forces, scientists soon discovered a mineral, F304, which they called "magnetite". Magnetite was first discovered within a particular bacterium that oriented itself in line with the North-South poles; it was then discovered in the heads of birds and Elasmobrachs which are all organisms known for their migratory tendencies (9).

Scientists agree that there are three general methods for detecting magnetic fields. One such way is the biogenetic magnetite complex. Though the magnetite complex's characteristics are consistent among a variety of organisms, little headway has been made with regards to understanding its interactions with a still unknown type of sensory organ for example, hairs, ion channels, etc. (8).

Chemical magnetoreception also serves as a method for detection. This process involves the spin states of molecules and a skewing of possible products to one more common outcome. Though it is thought that chemical magnetoreception is involved with photoreception of the retina, scientists are still skeptical of this method since these types of reactions usually require a much stronger magnetic field to produce any significant skewing of products (3)(8).

The last method of magnetoreception, electromagnetic induction, occurs in sensory structures of Elasmobranchs called the "ampullae of Lorenzini". Electroreceptors at the end of these ampullae detect subtle voltage changes in the current (while taking into account the consequence of their own movement through the water) (8). Though direct evidence of electromagnetic induction in Elasmobranches has yet to be found, it is already speculated that this type of system would be impossible for terrestrial organisms. This type of reception is so natural to the Elasmobranchs because they live in highly conductive salt water. For an induction-based system to exist in terrestrial organisms, a freely rotating internal current loop would be required as well as a specialized transduction organ as least several millimeters in diameter. I've always wondered what that hanging ball in the back of my throat did - maybe now I know!

Dr. Granville Dharmawardena of from The University of Colombo suggests that, "Twentieth century transcended science enables us to scientifically confirm that such concepts as impermanence, rebirth, telepathy and selflessness taught by the Buddha are true phenomena of nature which are beyond three spatial dimensions and therefore beyond classical science." (10) I tend to disagree with Dr. Dharmawardena's assumptions about "classical science". If we only experience the phenomena for which we have sensory receptors, then who's to say that what we experience as humans is "Ultimate Reality"? Classical science includes the phenomena of magnetoreception - a completely foreign reality to humans, yet an accepted type of reception among scientists worldwide. If this type of reception has already been revealed, then what other forms of matter are out there that we will never know about due to our poor diversity of accurate perception. So as an ever-evolving classical scientist I can safely say my home is never more than a short ride away.

References

1) Asia Africa Intelligence Wire, Oct. 7, 2002 "Buddhism's Dialogue with Science" Chopra, Swati
2)Trans4mind.com, public opinions on reality
3)University of Illinois at Urbana - Champaign, "The Magnetic Sense of Animals"
4) Ascribe Newswire, May 12, 2004, Wednesday; "Chemical Reaction in Birds Provides Sense of Direction During Migratory Flights; Study Could Help Identify Mechanism of Magnetoreception in Animals, Humans"
5) Nature, Aug. 5, 1993 v364 n6437 p491 (2)
6)University of California Irvine, a research project on integrated reception in birds
7) Highlights for Children, Oct 1999 v54 i10 p24; "The Magnetic Sense"; Myers, Jack.
8)Duke University, a discussion on magnetoreception
9) Journal of Applied Physics, May 1, 2000 v87 i9 p4653-4658; "Structure, Function and Use of the Magnetic Sense in Animals"; Walker, Michael; Diebel, Carol; Green, Colin.
10)"Buddhism and Modern Science, Buddhist opinion by Dr. Dharmawardena

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