Can cows sense magnetism? The debate continues

In 2008, some scientists proposed that cows can sense magnetism and actually line up in fields along Earth's magnetic lines. It's the sort of paper that everybody in the media wants to talk about for, roughly, two weeks ... and then never mention again.

But that's not how science works. One research paper does not an unquestionable fact make. Luckily Discover's Discoblog has been kind enough to update us on the current state of magnetic cow research. Shorter version: This issue is far from settled, with a second research team attempting to poke holes in the original study. Nevertheless, outside researchers say, the original findings still look strong. There is evidence that herds of cows stand along magnetic lines, and fail to stand along those lines in the presence of magnetic-field distorting high-voltage power lines. Whether this is absolutely the case and, if so, why, remains a bit of a mystery. Needs moar research.

... an analysis of Google Earth images by another team finds no such lining up. In a back-and-forth over the last year in scientific journals, the first team reanalyzed the second’s data and said that half of the images were useless, since they were near high-voltage power lines or contained hay bales or sheep instead of cows. Plus, the first team points out that the second team looked at single cows within herds instead of herds as a whole, and it’s pretty clear at this point that animals in herds and flocks aren’t operating as independent entities. The second team retorts that their images were too okay to use, and the first team may have been looking at the wrong pictures.

Image: Cows, a Creative Commons Attribution (2.0) image from 35463710@N06's photostream



    1. If indeed the magnet and its accumulated irritants acted as a compass, this would incline the cattle to maintain a given orientation longer than would otherwise be the case, but would not incline them to orient north-south.

    2. It’s amazing that all those articles were written in 2008 and no one thought to speak to the men (and women) who know cows best.

      I think that you solved the mystery ahecht, and so your revelation has been featured as the lead to this article at the Pewlpit.

  1. It’s an interesting observation that would warrant some study, but it wouldn’t explain this phenomenon for red and roe deer.

    For the life of me, I can’t think of an evolutionary explanation of why it would benefit cows to align themselves with the magnetic field.

  2. What about daylight? Most of the cattle-ranching regions aren’t terribly close to the equator, so standing north-south at or near noon will minimize the surface area exposed to the sun, and could offer some shade to the face and eyes; alternately, could maximize sunlight to the face and eyes. And if the cattle wanted to maximize sunlight exposure in the chill morning air, they’d also face north-south then.

    1.  That’s most likely explanation. We had a small herd of cattle, and they would congregate in the winter/fall in the high sunlight areas..and in the summer would hunker down in high shade areas in the heat of the day.
      The solar heat might help with their complicated digestion system.

      Cow’s are not migratory–So, I doubt any magnetic navigation benefit would apply.

  3. Walking towards Drumnadrochit in Scotland one evening back in ’78, we encountered a herd of cows that had packed themselves into a corner of their pasture that led uphill to a fence.

    The ones at the bottom kept saying “MOOOOVE”; we waited for the ones at the top to say “No ROOOOM”, to no avail. Didn’t check for magnetic pull tho’.

  4. Farmers have known for  years  that cows tend to face into the wind. It has nothing to do with magnetism but comfort. They don’t want to be blown-over.

  5. Since a cow can only walk the direction she faces, shouldn’t we see a lot of north/south ruts out in the fields?

  6. Too many variables.  Outdoor cattle could be orienting to wind, to topography, to the pattern of distribution of forage plants, to the sun or stars, or to the earth’s magnetic field, not to mention the nearest highway.

    The right way to get at the question—can they sense magnetic fields or not?—would be to put them in an indoor, artificial magnetic field and then rotate the field 90 degrees at random times.  Then any difference in their behavior could be attributed to their sensing a magnetic field, not some other variable.

    1. Without any controls, this would be a survey with the influence of all these elements quite important, and largely obscuring any magnetic influence.  In theory, though, it isn’t. 

      The big control of the study is the presence or absence of high-voltage power lines.  That’s a very good equivalent of the “artificial magnetic field” that you’re talking about.  They significantly alter local magnetic fields, and presuming that the authors chose a randomly-distributed orientation of power lines across grazing areas (I’d imagine this was verified), should work as an excellent control case.

  7. The only time cows ‘line’ up is when walking a path. and those paths are dictated by the landscape. In a field cows stand in a herd, not a line. They go wherever they see food/grass nearby. 

  8. I remember an art project.
    You know those little cut up word with verbs, nouns, adjectives…used for ‘fridge magnets you could randomly assemble into a poem on the ‘fridge?

    Someone used the same concept–painting the words on cows. So the cows would herd randomly and create a ‘cut up’ poem.

  9. It seems like a good idea to use a herd of cows with magnets as a control for a herd without.

    I built my first rail gun using a cow magnet for a projectile. By the time i upped it to 12 stages
    it had the power of a 9mm pistol round.

    Love those cow magnets. How do they work?

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