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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.
posted on behalf of Ruth Rosin: Rebuttal to comment by David Deal (DD): The authors of the reported study indeed did not attach any magnets to birds. They did not even study any living organisms at all, and their study is irrelevant to navigation by living organisms, because there has never been any valid evidence that any subhuman animals use the earth's magnetic field to navigate. The presence of magnetizable granules in various organism does not warrant any conclusions that the animals that have such granules use them as magnets to navigate. When the granules are found, they are never associated with any sense-organ. Moreover, the granules occur in widely varying amounts in individuals of the same species from different environments, and even in different individuals of the same species, in the same environment. All this raises very serious doubts regarding the possibility that the granules might serve any important biological function. The granules are obviously of an environmental origin. They enter the body with the food and/or water ingested, and are most likely simply useless junk, sequestered in specific tissues, because the animals' excretory systems are unable to excrete the granules to the outside. I have no idea where DD obtained the information that "lobsters constantly reorient themselves along weak magnetic field lines during specific seasons". Right now I cannot even imagine why the lobsters would ever do that, let alone do it during a specific seasons, and what use they might at all make of it. (It would be helpful if DD could provide a reference to the relevant scientific publication.) I do remember having seen several years ago a report which claimed that lobsters were affected by magnetic fields created by passing an electric current through metal coils. The lobsters were monitored by a scuba-diver, who had to repeatedly abruptly swim to the surface & back down, to give instructions to colleagues in a boat, when to switch the electric current on, or off. But the possible effect of the observer's sudden swimming motions on the observed animals, was completely ignored! The belief in the existence of "instincts" is basic to the whole issue, because it first misled not a few biologists into believing that honeybee-recruits had an "instinctive" ability to extract & use for navigation, spatial information contained in foragers'-dances, that scientists can extract only by relying on a considerable amount of preliminary scientific research, which honeybees obviously do not do. Shortly afterwards it misled many other biologists into believing that migratory birds that migrate for the first time, without the company of experienced adults that had already migrated before, have an "instinctive" knowledge of the route along which they need to migrate, over terrain they had never even visited before. Groundless claims for navigation by use of the earth' magnetic field, based on shoddy research, then quickly spread to homing pigeons, as well as various additional migratory animals that migrate by flying, or swimming.