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[The following is an exact transcript of this podcast.]
Don't be fooled by those big bovine eyes and the mouth slowly chewing cud—cows have a magnetic personality. At least that’s the claim made by German researchers in the August 26th issue of the Proceedings of the National Academy of Sciences. Using Google Earth images, the scientists looked down on over 8,000 cattle around the world. And, when grazing or resting, cows tended to face either magnetic north or south.
The researchers combined field observations with the satellite data and discovered that herds of both deer and cattle tend to align themselves north-south. Factors like wind and the angle of the sun had little bearing on how the animals stood. More often than not, like needles of a compass, heads swiveled northward. While it’s been known that birds, bees and fish use the earth’s magnetic fields for orientation, this study is the first to point to a magnetic sense in large mammals. The scientists speculate that this behavior may allow the animals to stay spatially oriented. In case danger lurks and a cow needs to make any sudden…moos.
—Adam Hinterthuer
> Related Story: Cattle and Deer May Sense Earth's Magnetic Field
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47 Comments
Add CommentThat's Quack-tastic
Reply | Report Abuse | Link to thisIt doesn't suggest a magnetic sense at all. Any creature will notice a difference between N and S due to daily movement of the sun, with no magnetic sensing required.
Reply | Report Abuse | Link to thisYeah, the cows are just looking to even their tan.
Reply | Report Abuse | Link to thisOh, what tripe!
Reply | Report Abuse | Link to thisConsider a much simpler and more likely explanation: bovine gaseous emissions. The bovine species is well known for the quantity of such emissions, it being a significant contribution to greenhouse gases. And we can readily postulate that no species particularly enjoys the olfactory stimulation produced by its own emissions, and that bovine individuals would fall into this camp. Couple that with a general average east-west wind direction, and the near-continuous digestive process that occurs in these beasts, and you will see immediately that an animal with its olfactory organs at essentially the same height as its emissions portal would have a strong incentive not to align the two with the prevailing wind. This lesson would be learned well and early in the animal's life, and the behavior would persist even when the winds were calm.
What tripe indeed!
I'm guessing this is almost exclusively done with Northern Hemisphere cows. My money's on the Southern cows facing south, you know, so they're not staring into the sun all day. I'm not going to waste my time proving, though, because who cares if cows have a compass? It's not like they're going to be navigating any time soon.
Reply | Report Abuse | Link to thisActually, that is really bizzare for a herd instinct animal. Shouldn't someone be looking in every direction for threats? Does this mean that if they oriented the feed troughs in feedlots E-W the cows would be more contented?
Reply | Report Abuse | Link to thisYou have got wonder how much is spent on studies like this? When all they had to is ask any farmer/rancher and they would have told them. 30 years ago was the last time I raised any beef and I know.
Reply | Report Abuse | Link to thisthats because they like to have the sunshine on their sides and the sun moves from east to west.
Reply | Report Abuse | Link to thisThis is so untrue. These scientists need to get a life!
Reply | Report Abuse | Link to thisthats because the cows like to have the sunshine on their sides and the sun goes from east to west
Reply | Report Abuse | Link to this8000 Cattle surveyed? That's a pretty small sample size. Australia alone has around 23,000,000 cows. So that's .03% (not 3% but 1 tenth of 3%. Now expand that to the world. 1.53 billion cows in the world according to the International Erosion Control Association, so now the sample size is .000005% of the total population.
Reply | Report Abuse | Link to thisI was always told that a large sample size is essential for statistics.
Some of the comments are ridiculous. Why? First read a couple examples, and then I'll explain!
Reply | Report Abuse | Link to thisSome previous comments: "It doesn't suggest a magnetic sense at all. Any creature will notice a difference between N and S due to daily movement of the sun, with no magnetic sensing required. "
another: "thats because the cows like to have the sunshine on their sides and the sun goes from east to west "
So why are these comments ridiculous? Well, the very article they're commenting on clearly states that "factors like wind and the angle of the sun had little bearing on how the animals stood".
The article was really only about a paragraph long people. Anyone care to conduct a study on short-term memory loss while commenting about online science articles? Yeesh.
Cows tend to graze in fallow fields, which may well have been plowed the previous year. Farmers tend to orient their plowing with the neighboring roads, which humans typically lay out in a N/S/E/W-oriented grid, and they prefer N/S plowing because it tends to keep the low sun out of their eyes when they do this work in the early morning. So lazy cows who desire to "walk with the grain", so to speak, because it's less work and better eating, may simply find it easier to follow the N/S furrows already laid down.
Reply | Report Abuse | Link to thisThat's udderly silly and, yes, tripe. The validity of statistical samples is by weight, not absolute number. 8,000 cows weight about 16 million pounds. Of course, if the study were on mice it would take millions of the little rodents to get such valid results. (p.s. pet mice run faster on N-S oriented treadmills.)
Reply | Report Abuse | Link to thisIt doesn't matter. Sample size needs to be large enough to account for variance, providing for meaningful statistical and thus predictive power. The size of the sample is not dependent on the actual size of the populations being inferred. If that were the case, no studies on say, human behavior, that used 100, 1000, or even 10,000 subjects would be valid since the entire population of humans is greater than 6.6 billion, according to your prescriptions. I'm curious where you learned how to determine what's an appropriate sample size for a given population.
Reply | Report Abuse | Link to thisThat's an interesting point. I'd like to dig into this article (if I had time or really cared that much) and see if this was something that was, or could be, controlled for, given the visual resolution on GoogleEarth.
Reply | Report Abuse | Link to thisThe dataset is not unbiased. Google Earth prefers images with minimum cloud, and often the sun's shadow shows they are taken in the early morning. I accept the hypothesis that bovines have a magnetic sense, but weren't the authors looking at cows when there is little wind and perhaps in the orientation they chose during the night?
Reply | Report Abuse | Link to thisWhat amuses me more than the article itself are the comments ;-)))
Reply | Report Abuse | Link to this"factors like wind and the angle of the sun had little bearing on how the animals stood"---That is something the assay should really dig into. Furthermore,by ruling out these two factors, it cannot jump to the theory that cows are magnetic inspired. Still there are more things to be analysised.
Reply | Report Abuse | Link to this"Factors like wind and the angle of the sun had little bearing on how the animals stood."---This is something the assay should really dig into. Plus, even if the wind and the angle of the sun have nothing to do with the fact, there are millions of other factors could count for the magnetic inspired cows, since mammals have a huge difference with the bees, birds, and the fish.
Reply | Report Abuse | Link to thisWhy do so many people rant on about something they know nothing about?
Reply | Report Abuse | Link to thisIf one were really interested, he'd spend the time to learn a little more about the study rather than waste it with ignorant and uninformed postulations. And then it goes on back and forth among commenters - What prattle!
Maybe cows do not like sun shining into their eyes?
Reply | Report Abuse | Link to this"looked down on over 8,000 cattle" .
Reply | Report Abuse | Link to thisYes they were OVER the cattle. Some proper grammar and usage would help.
They "looked down on MORE THAN 8000 cattle." How can you expect to have any respect in what you say if you phrase it like a TV Newscaster?
The true significance of this research has been overlooked. Once we know that these creatures have a predilection for a particular orientation, we need to understand the prevalence of exceptions. What obstacles would cause the cows to veer off course? There's only one obvious choice and the researchers need to take this one step further, by analyzing this data to determine the natural occurence of those obstacles. That result in an article entitled "Google Earth allows scientists to measure cowpie density". And in a world of butterfly effects, this new data will need to be fed into climate models.
Reply | Report Abuse | Link to thisThe cows don't like the sun in their eyes so they face north. Most photographs are taken near noon with the sun out, on clear days. Was this factor considered.
Reply | Report Abuse | Link to thismooooooo
Reply | Report Abuse | Link to thisAligning themselves is to be beneficial for cows?
Having spent many years in Texas where the observation of cattle is almost inevitable, I do believe these guys are mostly full of crap. There are two directions that appear to be default settings for the facing of cattle - Downwind and toward feed. Now, these "German scientists" might have been performing their tests with cattle containing "cow magnets." I couldn't say whether this might or mightn't influence the experiment. This, I would think, might have something to do with the orientation of said cow magnet within the gullet of aforementioned cow.
Reply | Report Abuse | Link to thisNaaa, this is just so much bull... so to speak.
ssdxx you are silly! cows don't know that the sun sets in the west and rises in the east!
Reply | Report Abuse | Link to thisSirs:
Reply | Report Abuse | Link to thisIt's reports that this that make me absolutely LOVE science.
Wonderful reportage. Very droll, indeed.
I remain,
Jacomus
Out here in the West, where there are free-range cattle, when you drive into a freeway on-ramp, you first cross a cattle guard. This is a matrix of steel bars with big gaps between, that mess with the feet of cattle. The most interesting thing about it is that someone figured out that you get the same benefit if you just PAINT what looks like a cattle guard on the asphalt. So cattle have enough intelligence to recognize a life-size painting of a cattle-guard as representing a cattle-guard, but NOT enough intelligence to tell a real one from a fake one. What is the likelihood of cattle having that precise level of intelligence? What Darwinian mechanism of natural selection would peg their intelligence at that precise level? Is it that cows who didn't recognize the painted item wandered onto freeways and died, and so did those who were too smart to be fooled by it? When did this weeding out occur? It had to be within the lifetime of the Interstate Highway System, which started with the Eisenhower Administration. Is this one of the fastest examples of Darwinian evolution ever seen among mammals?
Reply | Report Abuse | Link to thisGlad to see this thread...
Reply | Report Abuse | Link to thisI've long wondered (and should have looked into) why cows seemed to face mostly in one direction or the opposite. I thought it might be because they kind of mosey in a group. But,now I realize that, obviously, cows are magnetic! Similar to the old fashioned magnetic toy black and white scotty dogs. Clearly, the COLORS black and white are polar and magnetic opposites (think of Yin and Yang) and it's the color that causes this effect. The reason that not 100% of cows align North and South is because many of them are BROWN and white - thus weaker magnets. Hm-m-m-m. Just a theory.
Rob Browne
Glad to see this thread...
Reply | Report Abuse | Link to thisI've long wondered (and should have looked into) why cows seemed to face mostly in one direction or the opposite. I thought it might be because they kind of mosey in a group. But,now I realize that, obviously, cows are magnetic! Similar to the old fashioned magnetic toy black and white scotty dogs. Clearly, the COLORS black and white are polar and magnetic opposites (think of Yin and Yang) and it's the color that causes this effect. The reason that not 100% of cows align North and South is because many of them are BROWN and white - thus weaker magnets. Hm-m-m-m. Just a theory.
Oh, God. Scientific research funds are spent on THIS? No wonder we're so... late, in space, physics, health...
Reply | Report Abuse | Link to thisOh, God...
the fact that most cows have a magnet introduced in their rumen to prevent hardware disease may be correlated to their north south orientation. the magnet is usually a plastic coated rod and it may be more intrusive when it is oriented side way
Reply | Report Abuse | Link to thisThis is just so, so wrong ... These researchers have demonstrated a singular lack of imagination by latching onto the obvious notion of a hitherto unknown sensory apparatus to explain their observations. The truth is at once both simpler and more sublime. What we see here is actually emergent behavior arising from subtle interactions between a trio of co-evolved species, a symbiotic relationship between cowflies, cowbirds, and cows. Here's how it works. Cowflies like to hang around cows for obvious reasons, but they are subject to predation by cowbirds, which understand the congregation of favorite insect meals around the bovines. The cowflies can generally avoid detection by the cowbirds if they can hide in the shadow of the cow, and to improve their odds of doing so, they have evolved a behavioral trick to control the situation. Certain cowflies buzz around the ears of the cow until it turns close to a N/S axis, which (since the sun travels E/W) tends to place the cow crosswise to the sun's path and maximize the available shaded area when averaged across a full day. There is, of course, an extra risk of exposure to predation from the cowbird (which sits atop the cow) while this directional control is being applied, but on a statistical basis (which is all that matters in evolutionary terms) the larger community of nearby cowflies enjoys a greater likelihood of survival. Thus we see that a delicate interplay between species can result in unexpected behavior not attributable to just one organism, and any attempt to get the cows to replicate their behavior under indoor laboratory conditions would be doomed to fail unless the entire mini-ecosystem were replicated, an unlikely situation unless the interaction is already understood. In retrospect, the conclusions in this paper are a clear case of the researchers being blinded by the data and the modern methods by which it was collected and made available to them. Had they stepped away from their screens, gone out to visit the real world, made direct observations in the field (e.g., cows flicking their ears when the cowflies gather), and talked to evolutionary biologists, they would have avoided this public embarrassment. Let this be a warning to future scientists.
Reply | Report Abuse | Link to thisI do also think that it is not that persuasive to use only these satellite images to draw the conclusion, unless corresponding physical structures are detected.
Reply | Report Abuse | Link to thisThose who believe that cattle mutilations are done by extra-terrestrials often bring up the fact that in many cases, the dead animals are facing the same direction. They imagine that the cows are taken aboard the spaceship, experimented on, and then returned using some mechanism that causes them to be lined up in this way. I wonder how this news is affecting that "field of study."
Reply | Report Abuse | Link to thisDoes this mean if you tipped one cow, there could be a dominoe affect around the world since they all line up?
Reply | Report Abuse | Link to thisWe need a follow-up study. Does drinking cow's milk correlate with the ability to give good directions?
Reply | Report Abuse | Link to thisIt is the result of ferromagnetic influence. Here in the mid west most tract housing homes have the long ridge line axis on a north-south orientation. The nails used in their construction must be responsible.
Reply | Report Abuse | Link to thisKnowing that the cows follow some sensory signal is only half the story. We also need to explain the evolutionary advantage conferred on the animal by its following this signal. In the case of cows, it helps to know something of their anatomy. Aligning themselves on a N/S axis helps them to take advantage of the Coriolis force to move food between their four stomach compartments.
Reply | Report Abuse | Link to thisWell known that cows are Santa worshippers, face north to pray.
Reply | Report Abuse | Link to thisHello!!!!! A cow is a female. Females give birth and protect the young. Winds usually come from the west. The cow stands facing north or south to provide a shield between windy weather and the nursing calves.
Reply | Report Abuse | Link to thisThis is just a matter of simple physics. At the size and weight of a cow, small effects are greatly magnified. For a four-legged beast, one such effect is the difference in centripetal acceleration between the southernmost and northernmost pairs of legs as the animal stands. Cows mostly live in the mid-latitudes, where the surface of the earth lies at a great angle to the axis of planetary rotation. Thus in the Northern Hemisphere, the southernmost legs are farther away from the planetary axis than the northernmost legs. Countering the resultant difference in centripetal force can become very tiresome to an animal that spends all day standing. These mechanical differences can be easily accommodated by the different musculature of hindquarters vs. forequarters, if the animal stands on a N/S axis. But standing on an E/W axis instead creates a slight left/right tipping effect, and a small but persistent lateral bending pressure to the spine, which is sufficiently uncomfortable that the animal is forced to move out of that position. A similar effect is not seen in even larger animals such as elephants because they live in equatorial zones, where the surface of the earth is nearly parallel to the planetary axis, and so the force differential effectively disappears from their habitat. What we see, then, is that this phenomenon is due to kinesthetic sensory input, not animal magnetism.
Reply | Report Abuse | Link to thisSociologists should study why our paper has launched such a big resonance. We do not understand it. Anyhow, please read first the original paper in PNAS and then discuss, comment or criticize. If you do not have access to PNAS, please contact us - as did about 600 other people aready. There are many misunderstandings, because you rely only on a second-hand story mediated by journalists. As a reader of Scientific Amnerican, do you really think that PNAS would accept a paper for publication which is not scientifically sound and where alternative trivial explanations (Sun, wind, etc. were not considered)?
Reply | Report Abuse | Link to thisYou may read also our answers to some misunderstandings under
http://www.nature.com/news/2008/080825/full/news.2008.1059.html
Scepticism is good, fairness is better!
By the way this study did not cost the community a penny - it is a perfect example of "cheap science" - we did it on evenings, in our leisure for free (Google Earth is free) - and as far as observations and recordings of deer in wildness are concerned (fully ignored by media) - this was done in our free time, and the costs (for petrol) were covered by us (so do not worry about where the grant funds have gone - the study was done - as far as time and money is concerned - on the costs of our families).
Hynek Burda, Sabine Begall, Jaroslav Cerveny, Julia Neef, Oldrich Vojtech
It makes sense to me that ruminants who chew their cud for prolong periods would face away from the rising and setting sun while doing so. The theory about the gas emissions makes sense if the prevailing winds are E - W.
Reply | Report Abuse | Link to thisWhat is your exact contact info?
Reply | Report Abuse | Link to this