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Special Molecule Gives Birds a Magnetic Biocompass

Aaron Rowe writes "CORDIS news reports that a team of scientists has identified a family of molecules called cryptochromes that allow migratory birds to sense magnetic fields. Curiously enough, these molecules only function when accompanied by blue light. The article also mentions, 'The researchers also suggest that, as cryptochromes have been strongly conserved throughout evolution, all biological organisms could have the ability to detect magnetic fields, even if they do not use them.'"

18 of 276 comments (clear)

  1. Hrm... by PieSquared · · Score: 5, Funny

    Where do I sign up to get these powers enabled? I totally would go for it, even if it is a really lame 6th or 7th sense. Like, if I was lost in the woods with no cell phone and nothing to make a shadow with, and no running water... it could be mildly useful!

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    1. Re:Hrm... by Smallpond · · Score: 4, Funny

      "Where do I sign up to get these powers enabled?"

      It's a BIOS setting. You have to turn it on at conception.

    2. Re:Hrm... by Gotta+ask+yourself.. · · Score: 4, Insightful

      You jokingly stress an important point there: might this molecule be related to the orientation sense some people seem to have more developed than others?

  2. My brother-in-law does sense it by WindBourne · · Score: 4, Interesting

    When he gets off the plane at DIA, his first question is which way to north. Once he has his berings, he always knows his directions. Even when traveling through the mountains, day or night, he is able to figure out the direction quickly. Pretty impressive. What I find interesting is that plane travels screws him up. Once on the ground, If he does not get his bearing quickl, he appears to get more uncomfortable as time passes.

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    1. Re:My brother-in-law does sense it by smilindog2000 · · Score: 4, Interesting

      We do have a built-in gyroscope, though not a compass. I'm pretty sure guys have a stronger sense of it then girls. Makes sense... hunting and all.

      I have a good sense of direction, but now and then I get all messed up. It's a really strange feeling when I realize this has happened, and the internal gyro has to flip 180 degrees. There's a sense of the world shifting, almost like motion.

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    2. Re:My brother-in-law does sense it by Doc+Ruby · · Score: 4, Funny

      6/20 vision (assuming you're using the British/meters notation) means your friend had to stand 6 meters from something that others can see clearly at 20 meters. The only doctors wanting to study those eyes would be optometrists wanting to sell him glasses.

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    3. Re:My brother-in-law does sense it by OverlordQ · · Score: 4, Insightful

      When he gets off the plane at DIA, his first question is which way to north.

      Um, if he actually could sense the magnetic field, he could tell which way was north and which was south. Thank God we dont have to tell magnets which say is 'North' to get them to work.

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  3. Radio by Spazmania · · Score: 4, Funny

    And since radio is just a modulated electromagnetic signal, we should be able to pick up Rock 'n Roll on our teeth by exposing them to blue LEDs. It remains only to train our brains to understand this new sixth sense...

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  4. Reminds me of a Bill Bailey joke by Centurix · · Score: 4, Funny

    Where he was reading Brief History of Time and read "light is effected by gravity", to which he concluded that it was easier to drop things in the dark.

    -1 offtopic.

    Mind you, maybe I could strap a blue LED to an albatross and find my way home when I'm drunk.

    +1 ontopic.

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  5. Hey birds! by cryptochrome · · Score: 4, Funny

    I'm way ahead of you.

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  6. F=IL X B by afmstuff · · Score: 5, Insightful

    This is interesting in the sense that these are very low frequency (~0Hz) fields which transfer much less power to the molecule which interacts with it than say visible light which operates at a much higher frequency and is comprised of a coupled electric and magnetic field. Of course the latter has been known to be sensed by sighted animals for quite some time. One way to view this is as an extension of the mechanism of vision- a photon causes a fast (actually one of the fastest reactions known) trans->cis conformational shift in retinol which drives a voltage down the optic nerve... the mechanism described in the FTA is the next step: once a radical is formed, it responds in a magnetic field. Apparently this response is also sensed. Interesting finding!

  7. Iron in your nose by TubeSteak · · Score: 4, Informative
    According to http://everything2.com/index.pl?node=nose
    • There's a compass in my nose?

    • All humans have a trace amount of iron in their noses, a rudimentary compass found in the ethmoid bone (between the eyes) to help in directional finding relative to the earth's magnetic field.

    • Studies show that many people have the ability to use these magnetic deposits to orient themselves-even when blindfolded and removed from such external clues as sunlight-to within a few degrees of the North Pole, exactly as a compass does.

    • Though no one knows how this "sixth" sense is processed by the brain more then two dozen animals, including the dolphin, tuna, salmon, salamander, pigeon, and honeybee have been found to have similar magnetic deposits in their brains to help them in navigation and migration.


    I will dispute their statement about pigeons though. I recall watching or reading something where the scientists put trackers on homing pigeons to discover how they found their way around. Turns out they follow landmarks.

    The pigeons often took indirect routes, because they were following a road. The scientists didn't figure this out even after they realized the paths were very odd... it didn't click until someone looked at a road map.
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    1. Re:Iron in your nose by Centurix · · Score: 5, Funny

      With a nose the size of mine I'm not looking forward to the polar shift. I'll have to wear kneepads and a helmet.

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      Task Mangler
  8. Detecting Changing Magnetic Fields by DrLudicrous · · Score: 4, Interesting

    Anecdotally, I have heard of many people "sensing" the magnetic field of an MRI scanner. I have had a few MRI's done on myself, and can attest to this feeling. It is strange, mostly in the head, somewhat like when one feels dizzy or just a tinge of seasickness. I think that is has something to do with the fact that as you enter the scanner, the field you experience changes quite rapidly. Once you are in the scanner, I haven't really noticed the queasiness as much, though it still feels strange. However, I attribute this second sensation more to the fact that one is contained inside a small tube with all kinds of weird noises and vibrations going around. So at the very least, some people seem to be sensitive to changing fields above some threshold.

    1. Re:Detecting Changing Magnetic Fields by DrLudicrous · · Score: 4, Informative
      You are right in some respects. The moment to which you refer is the nuclear magnetic moment of the hydrogen atom, which are quite plentiful in most living things, ourselves included, due to the prevalence of water. In MRI, the torque these moments experience causes them to change their alignment from being in the same direction as an externally applied magnetic field (hence the big MRI magnet), to one that lies perpendicular to the direction of the external field. As they do this, the precess about the external field axis at a rate called the "Larmor frequency" (i.e. they rotate about it). This causes the magnetic flux inside the MRI receiver coil (more or less a loop of wire) to change, and by Lenz's Law, an EMF (voltage) will be induced. This is the signal that is detected.

      Note that while the magnetic moments are being manipulated, the actual water molecules themselves are more or less unaffected. This is one reason that MRI/NMR is such a great way to measure molecular self-diffusion- the phenomenon of diffusion is unaffected by all the magnetic fields being bandied about the sample. So to sum up, the "torque" the water molecules experience is one that affects only the magnetic orientation of the hydrogen atoms in your body, and not the actual physical orientation. And the signal that an MRI machine detects is not coming from the return to equilibrium of the water molecules as much as it comes from the precession of the asffected magnetic moments about the direction of the external field.

  9. Re:I know this is SERIOUSLY OT but I need to ask. by Rix · · Score: 4, Funny

    Oh get over it already. All of you have been running around like a little girl with a skinned knee for 5 damned years. Suck it up.

  10. Re:Extinction by FleaPlus · · Score: 4, Informative

    I think you've just hit upon a new theory as to why the dinosaurs went extinct. Is there any evidence, for or against? How well are the dinosaur extinction event and the magnetic pole flips narrowed down, and could the dinosaur extinction be a delayed reaction?

    Well, the thing is, magnetic pole reversals actually happen pretty often, according to Wikipedia at a rate of 1-5 events every million years. Since the dinosaurs lived 65-230 million years ago, by looking at this graph we can deduce that during their existence they experienced a few dozen pole reversals.

    Now that I look at it though, it is somewhat interesting that the Cretaceous Long Normal, an abnormally long (~40 million year) period during which there were no pole reversals at all, ended around 15 million years before the dinosaurs disappeared. I personally think it's just a coincidence, though.

  11. There is news, very small and buried at the end by Alfred,+Lord+Tennyso · · Score: 5, Informative

    It's a very badly written press release. In fact the actual science has zilch to do with birds and everything to do with plants using the same molecule. They described the way light and magnetic fields interact to change the way the plant stem grows, except in plants without the cryptochrome molecule.

    Which is just basic, everyday scientific advancement: a very small and excruciatingly dull thing, presented with a tie-in to something more interesting in an attempt to look sexier and get funding. Scientists hate doing it, but if you want to keep doing science, that's what you do.

    This article IS news, but only in the narrowest sense: new information. But after you take that new information, tie it in to something more interesting but only indirectly related (which you put at the front of the press release, and the actual new stuff at the end), then summarize it for Slashdot (skipping the stuff at the end), "news" becomes "olds".

    One final note: when I call the work "small", I don't mean to dis the grad students who worked thousands of hours tending the plants, measuring them, putting that data into the computer, analyzing that data, probably cutting them open and measuring that... such immense grunt work for a minor advance [promptly blown up into something irrelevant by university's press department] is the heavy-lifting of science. It's gotta be done but it's not glamorous or even interesting.