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Magnetic poles flipping and the effect on animals

  1. Jun 4, 2008 #1
    There is supposed to be a switch of magnetic poles in several thousand years which already started 150/200 years ago. This gave me an idea. Can the changing magnetic orientation cause the whales (and other large mammals living in the sea who use the earths magnetic field) to "crash" on shores and beaches as they often do?
    Also one question regarding the flip itself. I read on PF that the flip is supposed to be gradual. Slowly "sucking through the ground" from north to south. Does that mean that there will be virtually no magnetic field protecting us during certian period of time?
  2. jcsd
  3. Jun 5, 2008 #2
    It flips in the sense that it moves from one end to the other. Its a very gradual process that takes 10,000-100,000 yrs (??) to completely move.
    The question about the whales is an interesting one (i'm more familiar with birds, i didn't know whales magnetonavigated); because whales have existed for many flips - it mustn't completely destroy their ability to navigate. This might suggest that their magnetic navigation is largely experimentally/experience based instead of genetic.

    Whales will be beached naturally, especially towards the end of their life. Currently the primary reason to my knowledge is man-made sonar.
  4. Jun 6, 2008 #3
    I'm afraid the answer is no one really knows what will happen. It's true the magnetic field protects us from cosmic rays so one might first think we might get cooked but what we do know is that the last reversal did not cause a mass extinction (and I believe Homo Erectus was around then).
  5. Jun 7, 2008 #4


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    This is a question I myself have thought about at some length, especially the lack of protection from radiation. As you probably know, the current thinking about evolution is that it is not a gradual and constant process, as once thought, but a series of sudden outbreaks. If the Earth's magnetic field grows very week at fairly regular intervals and for short periods of time (on the geological and evolutionary scale), might these periods be marked by a drastic increase in the appearence of genetic annomilies? I also suspect the weekening of the magnetic field might have soemthing to do with the hole in the ozone layer (at the poles, where the magnetic field's protection is the weekest).

    I've exchanged a few e-mails with Dr Daniel Lathrope, but haven't really scratched the surface of these questions.

    BTW: Dr Dan's work at University of Maryland can be seen here;
    http://complex.umd.edu/index.html [Broken]

    The three-meter system is supposed to start running this fall!
    Last edited by a moderator: May 3, 2017
  6. Jun 7, 2008 #5
    Hmmm, why is this thread here and what happened to the requirement to support statements with refs? Mentors?

    Here are refs:


    There is nothing whatsoever that makes us certain that a magnetic pole flip is imminent. Perhaps the magnetic field strenght is reducing as it may have been higher recently than in the past million or so years. What goes up, must come down. And even if the field would collapse in the next few hundred years or so, it may restore eventually, and we would have just another geomagnetic excursion as has happened several times in the current Bruhnes magnetic chron.

    Furthermore there is no evidence, neither for climate nor for biota to react on large changes in the geomagnetic field.
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