Become a fan of Slashdot on Facebook

 



Forgot your password?
typodupeerror
×
Science

Dogs May Use Earth's Magnetic Field to Navigate (sciencemag.org) 32

sciencehabit shares an article from Science magazine: Dogs are renowned for their world-class noses, but a new study suggests they may have an additional — albeit hidden — sensory talent: a magnetic compass. The sense appears to allow them to use Earth's magnetic field to calculate shortcuts in unfamiliar terrain. The finding is a first in dogs, says Catherine Lohmann, a biologist at the University of North Carolina, Chapel Hill, who studies "magnetoreception" and navigation in turtles...

There were already hints that dogs — like many animals, and maybe even humans — can perceive Earth's magnetic field. In 2013, Hynek Burda, a sensory ecologist at the Czech University of Life Sciences Prague who has worked on magnetic reception for 3 decades, and colleagues showed dogs tend to orient themselves north-south while urinating or defecating. Because this behavior is involved in marking and recognizing territory, Burda reasoned the alignment helps dogs figure out the location relative to other spots.

Lohmann and a graduate student tracked the path of dogs on 233 separate trips spread out over three years: In 170 of these trips, the dogs stopped before they turned back and ran for about 20 meters along a north-south axis. When the animals did this, they tended to get back to the owner via a more direct route than when they didn't, the authors report in eLife...

Burda thinks the dogs run along a north-south axis to figure out which way they are. "It's the most plausible explanation," he says. Lohmann says the implication is that dogs can remember their previous heading and use the reference to the magnetic compass to figure out the most direct route home.

This discussion has been archived. No new comments can be posted.

Dogs May Use Earth's Magnetic Field to Navigate

Comments Filter:
  • ...why they are so attracted to lampposts.
  • I mean...

    REALLY?

    I'm doing SCIENCE! Sometimes the dogs ran north OR south so they must be following magnetic lines of deviation!

    And if you believe that I've got a book on phrenology to sell you.

    • Seriously... it couldn't have anything to do with visual clues like the sun.

      • Re:Really? (Score:4, Informative)

        by Calydor ( 739835 ) on Saturday July 18, 2020 @04:04PM (#60305033)

        If this is in relation to the same study I saw a couple of years ago they already accounted for things like wind, sun, shade etc. and found it had little to no effect.

        • assuming dog couldn't sense sun on cloudy day? there are a lot of reasons such an assumption could be wrong.

        • So they ran their study in the dead of night, I find that hard to believe.

        • There's so much more to how the sun impacts the environment than being able to see it directly.

          A simple example is that, in the Northern hemisphere, the South side of trees will be greener/have more growth.

          • in the Northern hemisphere, the South side of trees will be greener/have more growth.

            I'm not a zoologist, but I don't believe this also happens to the South side of dogs...

    • by account_deleted ( 4530225 ) on Saturday July 18, 2020 @04:01PM (#60305025)
      Comment removed based on user account deletion
    • I'm a bit skeptical of these claims too; while they lack some of the higher cognitive capabilities that primates are graced with, dogs are surprisingly good at figuring things out, and seem to (on average) have pretty decent spatial awareness. I'm assuming that these were trials were done during the day - can it be ruled out that were, perhaps, using features in the sky (sun, moon, clouds) or possibly other observations such as shadows for orientation? Dung beetles, for example, appear to be capable of some
      • by dgatwood ( 11270 )

        That's actually what the folks in the linked story about humans [sciencemag.org] did. They took two groups of people on a particularly winding road, then asked them to point in the general direction of home, and determined how many people could get within the right quadrant. To blind the experiment, they put magnets in the hats of half the people, and brass bars in the hats of the other half. The ones with brass had no trouble pointing in the right direction, whereas the ones with the magnets couldn't do it. It might b

    • by tragedy ( 27079 )

      It does seem like an experiment is in order. Faking the magnetic field with your own powerful magnets might be a good way to test. The problem is, it's easy to fool a dumb instrument like a compass with a faked magnetic field, but it's hard to fool an intelligent animal. If the dog can read the magnetic field, it may also be able to read the field strength and realize that it's too strong, or that the strength varies too much as it moves around, etc. If you have a sense of magnetic fields, it would make sen

    • Or they ran back and forth because they are confused?
  • Do you sense the sun? (Jackson voice of Nick Fury)

    Yes.

    Then put it on the LEFT!

  • I live ... (Score:4, Funny)

    by PPH ( 736903 ) on Saturday July 18, 2020 @04:59PM (#60305143)

    ... under some power lines. Dog just runs in a circle at 3600 RPM.

    • In all honesty, this would be one way to validate or invalidate the claims. A small collar that generates a randomly spinning magnetic field would be one way to confuse any existing magnetic sense. Alternatively, I suppose you could build a very large Faraday cage.
  • But they don't.

  • This is not a "first" for magnetic perception in dogs, nor is it very persuasive. There was research published, and much media coverage in 2014, for example slashdot! https://science.slashdot.org/s... [slashdot.org]
    There was a wonderful bit in the Canadian TV show "The Nature of Things": https://gem.cbc.ca/media/the-n... [gem.cbc.ca] (starting around the 33 minute mark). The orientation tendency is dependent on the stability of the ambient magnetic field at the time.

  • Haven't had a chance to look at this newer study but there were good reasons to doubt the conclusions of the original study. For instance, consider this post [columbia.edu] on Gelman's blog

    • Yeah, they eliminate times when the magnetic field is not "calm", whatever that means. Have these people ever used a compass? Does the compass jitter? Then why would a dog be confused? My guess is they decided that the magnetic field was not calm whenever the dogs didn't do what they expected.

  • I read the article casually.

    I tend to agree with the skeptics in this post that things like night-day and sun orientation are not accounted for, although the researcher, having done this for a long time, might know the answers to that concern. Personally, I have watched my own dog for years, and when he takes a shit he doesn't seem to give a shit which way he aims.

    The paper focuses on the dogs traverse. They can wander off to scout, but having made an arc-like outbound path, they will return more directly, akin to following a circle perimeter, then hustling back home on the chord or diameter.
    That entails a capacity to create a mental map of the space you are in. That does not require an absolute orientation to an external frame of reference, just a comprehension of your local space. So, magnetic field and even sun might not matter so much as the dog or anyone knowing that "I made a right, then another right, and I can get back home by another right rather than retracing my steps", even if Fido cannot say it it such explicit terms. The coyotes that cross my back yard every night to prowl find their way back home just fine without sun or moon.

    So, observing (doing experimental science) that dogs can navigate back to the start along a direct route regardless of the outbound path, the paper is good in that sense. But, the inference seems too much like forcing one interpretation over others without much validity for doing so.

    However, it is also important to note that biology does know how to use magnetism. Iron is abundant, so no surprise that primordial life had to learn to adapt, ignore, or utilize it. Certain archaic "extremophile" bacteria use iron for energy transduction. We are critically dependent on it, in hemoglobin, to transport oxygen. Certain bacteria are magnetotactic, able to move toward or along magnetic force lines, because they accumulate magnetite crystals. In these microorganisms, the crystal chains are substantial in size as compared to the cell as a whole, akin to our spine or liver. It is easy to see how force or torque on the chain will wiggle intracellular membranes or organelles, inducing spatially asymmetrical responses (such as motion of cilia on one side but not the other) that will cause the critter to deviate from or maintain its current track.

    Magnetitie crystals and magnetosomes have been found in higher taxa as well, including bees and bird species known to have remarkable navigation or homing abilities. They have also been identified in human brain. While we do not have a magnetic organ per se or an organized iron structure comparable to other neuro or mechanical structures such as hypothalamic nuclei or a heart valve, nonetheless it is there in people. Whether it is vestigial and irrelevant, or important in unknown ways, or truly a navigation transducer that some people unconsciously utilize, no one knows. But, it all goes to show that life is clever and complex, and we still do not know about much of it.

    Shit Ubu, shit. Good dog.

  • Dogs eat their own shit. 'nuf said
  • They use it to poop along the North/South Axis: https://www.npr.org/sections/t... [npr.org]

    • *sigh* I Ctrl+F'd to search for 'poop' to make sure I wasn't duplicating another comment, I didn't notice 'defecate' in the summary.

  • My dog has a little compass on her collar.

  • when they can open the damn door for themselves!

    • The hardest part for dogs is understanding how to pull the door towards them. It's very unintuitive for them. Doors that open outwards are easy. Many dogs can even work a round knob using their pads, but of course a French handle is more suited to their anatomy.
  • Try this experiment on huskies in Alaska or the Yukon Territory, where the magnetic declination can be over 20 or even 30 degrees.

    Color me skeptical.

Think of it! With VLSI we can pack 100 ENIACs in 1 sq. cm.!

Working...