Magnetism the 6th Sense. Do Humans Have It?

MisterDavy

Oliver Sacks talks about teaching himself - and other people - how to detect magnetic fields by carrying strong magnets in his pockets in this radio lab.

http://www.radiolab.org/2006/may/05/

Hope it's okay to post this, it seemed relevant, but I'm still new here and don't know all the rules.

Ryan_m_b

I think we've just discovered an infractoception

AlephZero

I wonder if there is a systematic bias introduced by Google Maps / Earth here.

Just for fun I went to Google Maps to look at my local area, which should have plenty of fields of cows and sheep. The images were certainly good enough resolution (e.g. road markings were clearly visible) and from the farming activity I would be confident dating them to within about +/- 2 weeks. But the strange thing was .... no cows. There were a few sheep, but only about 1% of the numbers I expected to see. This was a search around an area of about 10 x 5 miles - obviously not every square yard of it, but I know where to look.

Also there were no vehicles anywhere on the roads, which makes no sense considering the images were taken probably in June and certainly in sunny daylight conditions.

So ... considering these are very high resolution images if they are taken from low earth orbit satellites (200 miles?) I wonder if the effective exposure times are long, and anything moving is either invisible or filtered out. The few visible sheep (well, actually sheep-sized whiteish oval blobs) were much fuzzier than the rest of the image.

Can anybody confirm or contradict those observations from their own local knowledge of an area?

If thsi is the case, whatever the authors of the paper were counting, they may not have been cows doing what cows normally do.

I've no ideas about the deer.

Bobbywhy

The first line in the OP is: "* Dozens of animal species, from ants to whales, have well-documented abilities to detect the geomagnetic field and use it for orientation and navigation."

So I would say this thread is about more than just some cows. I found at least three evidently “mainstream” scientific articles that seem to be more than anecdotal. All of them affirm that a wide variety of animals use the geomagnetic field to navigate.

http://www.science.gov/topicpages/m/...ientation.html

www.seaturtle.org/PDF/AvensLI_2003_PhD.pdf

http://www.nmfs.noaa.gov/pr/pdfs/spe...posium2004.pdf

Ryan_m_b

The point isn't whether or not some animals have a magnetic sense, the fact that many do is well documented. The points on discussion are whether or not humans have it and whether or not this study is good enough to indicate that cows have it.

Bobbywhy

Ryan m b, Thank you for explaining this to me. Now I get the point(s).

Jim Kata

Radiolab did a small bit on this. Namely, they said that birds use the earth's magnetic field to guide them on their migrations. But, I think this would be like a seventh sense if it existed in humans our sixth sense is equilibrioception. Radiolab also did a cool show called "Where am I?" where they talked to some guy who lost his sense of equilibrioception.

jim hardy

Even if cows did sense magnetic North
why would they pefer it?

My guess is when they face North the southerly sun illminates the grass better.

Ryan_m_b

There is some debate regarding what classes as a "sense" but in actual fact we have nearly/over 10.

Bobbywhy

Would that same reasoning apply to cows in the Southern Hemisphere?

Cheers,
Bobbywhy

jim hardy

I was hoping somebody from Down Under would chime in !

jreelawg

Electromagnetic Radiation is not the same as magnetic field. Obviously, gamma rays would have an effect on a person.

mkillman

It's been proven many times and in many places that humans are sensitive to strong magnetic fields

I do not see what the debate is about it simple to understand

Moving thru a strong magnetic field with a conductive material generates electricity
Your nervous system is an electric circuit
Many haunted houses have been attributed to magnetized pipes
We are not nearly as sensitive to them as other animals but we are defiantly wired "excuse the pun" to be able feel them


http://www.medcom.lsuhscshreveport.e...rophys2004.pdf

johnbbahm

This got me to thinking about google maps. I did not find any cows, but I think I found cow shadows.
http://maps.google.com/maps?hl=en&ll...00862&t=h&z=20
The image seems fast enough to capture cars on the interstate.

As far as the original question, I read in Scientific American about Birds using the difference in the polarized sky, to tell direction. I tried it and in fact the north/south sky
looks very different than the east/west sky.

ImaLooser

.Here in Bali the natives have excellent sense of direction. It would be worth testing. I'd do it myself, but a rigorous experiment is too expensive. It takes a soundproof room and some sort of randomized mechanically rotating chair, I think. All directional clues other than mag must be removed.

Come to think of it, not even that would work if the clues come from natural sunlight. How could that experiment be done? I don't know.