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Published online 30 April 2008 | Nature | doi:10.1038/news.2008.788
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'Chemical compass' created
Lab work proves reactions can be influenced by the Earth's weak magnetic field.
Research published this week proves for the first time that chemical reactions can be influenced by magnetic fields as weak as the Earth’s — a vital finding for one theory regarding animal navigation.
Many animals are thought to use the Earth’s magnetic field to navigate, including not only birds but also some mammals, fish and even lobsters.
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The only living organisms able to use the earth's magnetic field to navigate are humans. And humans can do it only providing they manufacture, purchase, borrow, or steal, a magnetic compass. The scientific literature is full of claims that various subhuman animals use the earth's magnetic field to navigate. Unfortunately, all these claims are based on pseudoscience. For instance, many such claims are based on "determining" how migratory animals migrate, by studying the animals during the migratory season, under conditions where they are prevented from being able to migrate, (by being cooped in very small "orientation cages", "orientation funnels", or small arenas, or when they are tethered). It is, , in principle impossible to determine how animals do something specific by studying them when they do not do it! Claims that homing pigeons use the earth's magnetic field to navigate back home, are based on studying trained homing pigeons released far from home, after having very strong magnets attached to their backs, but ignoring the fact that the strong magnet, (not the bird), will certainly react to the earth's magnetic field, and turn to align itself in the direction of the earth's magnetic forces, thus forcing the bird to turn into that direction, and denying it the freedom to fly in any desired direction. To understand that it is necessary to realize that when a magnet is attached to the bird, the bird is attached to the magnet! The "magnetic compass" hypothesis for subhuman animals is the second greatest goof in the whole history of the behavioral science, after the first one, which is the Nobel winning "discovery" that honeybee-recruits navigate by using distance & direction information contained in their foragers'-dances; which humans alone can extract following a considerable amount of preliminary research. The whole field of behavioral science is sinking under the weight of a lot of rubbish based on the belief in the existence of "instincts", which has its origin in myth, and religion, instead of proper science. See Frank A. Beach. The descent of instinct. The Psychological Review, 62(6): 401-410 (1955).
The only living organisms able to use the earth's magnetic field to navigate are humans. And humans can do it only provided they manufacture, purchase, borrow, or steal, a magnetic compass. All claims that various subhuman animals use the earth's magnetic field to navigate, are based on none other than pseudoscience. For instance, there are very many claims published in prestigious scientific journals, stating that various migratory animals navigate by using the earth's magnetic field, based on the counter-scientific notion that you can determine how such animals migrate, by studying them during the migration season, under conditions where they are deliberately prevented from being able to migrate. It is, in principle, impossible to determine how animals do anything specific, by studying them under conditions where they do not do it! Claims that homing pigeons can use the earth's magnetic field to find their way back home, are based on studying trained homing pigeons, released far from home, with a very strong magnet attached to their back. It is the magnet (not the bird) that reacts to the earth's magnetic field, turning to align itself in the direction of the earth's magnetic forces, thus forcing the bird that is attached to the magnet, to align itself in the same direction, and consequently denying the bird the freedom to head in any desired direction! The claim that various subhuman animals navigate by using the earth's magnetic field, is the second greatest goof in the whole history of the behavioral science. The first one is the Nobel winning "discovery" that honeybee-recruits navigate by using distance & direction information contained in their foragers'-dances; which only humans can extract, and only after very lengthy preliminary research. The whole field of behavioral science is inundated by an almost endless amount of rubbish, due to scientists who still believe in the existence of genetically predetermined "instincts", even though the concept of "instinct" has its origin in myth, religion, and wishful thinking, instead of proper science. See Frank A. Beach. The descent of instinct. The Psychological Review, 62(6): 401-410 (1955).
Magnetite minerals occur naturally in some animals. It seems even humans may have a small amount in the region of the nose. There is evidence that more ancient humankind and ancestors had larger amounts of naturally occuring magnetite in their heads. The researchers in this current study did not attach magnets to the birds as far as I can see. They did however "create" an artificial chemical compass to study in the lab via spectroscopy. Apparently they report this "compass" aligned with the Earth's weak magnetic field (probably referring to extremely low frequency magnetic flow lines). Lobsters constantly reorient themselves along weak magnetic field lines during particular seasons. I do not see what any of this would have to do with 'instinct' or some sort of extra-sensory perception or 'gut feelings' that you allude to R.R. I do agree birds and other animals could use far more obvious means such as landmarks, pheremones, habit, learned behavior to get where they need to be. Yet magnetite is a real mineral found in animals and in the earth. Its also being investigated for its unique properties exhibited at the nanoscale in hopes of building meso-scale devices and other sensors as well as electronic instruments. The idea that a bird's eyes contain a chemical allowing it to "see" weak magnetic fields does seem a bit strange. From a neuroscience perspective I'd suspect humans utilize the deductive method of apperception. Reminds me of when someone 'knows' an answer or solution but really does not understand how they knew the answer. Many people may mistake this ability for what you refer to as the pseudoscience of instinct. One could think of a police detective who has a hunch but she really is drawing upon previous experiences and it is possible a bit of guesswork.