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People telling north from south.... spontaneously...

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Awitt
1044528.  Mon Dec 30, 2013 4:52 am Reply with quote

I have a pretty good idea of where north is when I'm at home, (Melbourne, Australia) but think it's got more to do with knowing every detail of the city (and state of Victoria)for when I was on holiday in England 10 years ago, I still had an idea of where north may have been, but wasn't 100% certain either.

 
Alfred E Neuman
1044532.  Mon Dec 30, 2013 5:00 am Reply with quote

I can usually tell North, but haven't tried in a closed room. I've always thought that it's more a case of being aware of my surroundings.

The position of the sun is always a good clue, and one that is dependant on both the hemisphere and distance from the equator.

 
mis
1044545.  Mon Dec 30, 2013 5:42 am Reply with quote

@gruffs I'm 44 and can still do it.

And something I didn't add, we did an experiment, I was placed on a board with casters, blind folded and taken into a room (well broom cupboard, it had no windows and was so dark the door could not be seen) and was turned around several times I was then allowed to step off the board and asked to point to North again, I did the same thing (eyes open as it was completely dark) and then the lights were returned when I said I was pointing. I was checked against a compass, and nailed it within 5 degrees deviation everytime.

I don't know how I do it, all I know is in my mums kitchen I know exactly where north is (within the same deviation) and I visualise, turn until my minds eye 'syncs' (a feeling that it's right, and it turns in complete sync with my body.) Then I point to where it would be if I were standing in my mums kitchen, and it's the same every time...

 
PDR
1044552.  Mon Dec 30, 2013 5:52 am Reply with quote

There are many animals which at least appear to be able to detect local magnetic fields - either in terms of direction or dip angle. AFAIK we have yet to definitively identify the specific cells or organs which form the magnetic sensors in these animals, but we are fairly sure they exist.

Virtually all animals on this planet evolved from common ancestors and share the majority of their genes (does it worry you that over 99% of your genes are the same as those of Michael Gove?) so it is more than feasible that humans have latent magnetic sensing organs in their DNA which get switched on occasionally when the genetic dice are shuffled at conception.

If there was some strong survival advantage then you expect to see this sensor becoming more common in humans, but the advent of smartphones with GPS and free navigation software probably be g area the benefit (although clearly some rudimentary navigation sensors would be of significant benefit to iPhone &iPad users). I wonder if anyone has ever looked into whether this "magnetosense" is more common amongst nomadic communities (e.g. the Tuargui) where the ability to navigate across featureless or changing terrains like deserts .most certainly WOULD be a "survival" characteristic.

PDR

 
Alfred E Neuman
1044554.  Mon Dec 30, 2013 5:57 am Reply with quote

Deserts are easy - you've almost always got the sun as a reference.

 
PDR
1044564.  Mon Dec 30, 2013 7:07 am Reply with quote

Alfred E Neuman wrote:
Deserts are easy - you've almost always got the sun as a reference.


Only if you know the time, and of course the nomadic tribes (and things like salt caravans) travel mostly by night. At night you can use the stars as a reference, but both sun and stars only give you a direction (not a position) yet experienced caravan-chiefs can navigate across hundreds of miles of ever-changing open desert to oases that are only visible from a couple of miles away.

There is a "folklore" thing called a "bump of direction" which some people allegedly have, and this could be indication of a magnetic "sense".

PDR

 
gruff5
1044565.  Mon Dec 30, 2013 7:19 am Reply with quote

PDR wrote:
... stars only give you a direction (not a position) yet experienced caravan-chiefs can navigate across hundreds of miles of ever-changing open desert to oases that are only visible from a couple of miles away...

The stars can partially give your position. The angular height of Polaris, the north pole star, above the horizon will be the same as your latitude. So, you could trek to the required latitude and then trek on that same latitude East or West until you hit the oasis. Though a tough call if only given a couple of miles leeway!

 
knightmare
1044575.  Mon Dec 30, 2013 8:21 am Reply with quote

Quote:
we did an experiment, I was placed on a board with casters, blind folded and taken into a room


Certainly worth mentioning. Perhaps you were still able to remember were the magnetic north pole is by using equilibrioception. Next time one could try to manipulate the senses beyond control, and also try pointing to something (blue dot, powerful magnet) you cannot detect with your senses.

 
PDR
1044583.  Mon Dec 30, 2013 8:53 am Reply with quote

gruff5 wrote:

The stars can partially give your position. The angular height of Polaris, the north pole star, above the horizon will be the same as your latitude. So, you could trek to the required latitude and then trek on that same latitude East or West until you hit the oasis. Though a tough call if only given a couple of miles leeway!


Indeed, and also if you happen to pick the wrong direction (east versus west!). To do this requires accurate angular measurement using a sextant or similar - something capable of resolving to better than five minutes of arc (a twelfth of a degree) to place you on a latitude line that's within even five miles of your destination. As far as I'm aware the nomadic tribes never developed this kind of instrumentation - nor did the Polynesian seafarers who have been able to navigate over the open ocean to distant islands reliably for over a thousand years. The whole chronometer/longitude malarky was required to allow "1st world" people to have accurate navigation over featureless vistas.

All of this is fragmentary evidence which (taken collectively) might tend to support the conjecture that some humans have a magnetic (or other) sense, but it's not conclusive or definitive.

It has been suggested that animals have such a magnetic sense - from migratory birds to hunting foxes (this latter was on the show recently), so it really isn't that much of a stretch to consider the possibility that humans, who share so much of their DNA, might also have it in a latent or less-developed form.

PDR

 
mis
1044585.  Mon Dec 30, 2013 9:07 am Reply with quote

@knightmare:

I can tell you after the board was turned around several times I was quite disorientated (and dizzy) I had to wait for my senses to settle (so I could stand straight) then I performed the same 'ritual' of visualisation and turning, and pointed north..

As for magnets, tried that, can't detect them, but then neither could the compass until it was within a few inches... I would expect I might see different results if the magnet was detected by the compass some several metres away.. I have yet to find such a magnet to experiment with.

 
knightmare
1044600.  Mon Dec 30, 2013 11:13 am Reply with quote

Oh, one could also try to walk (or swim) in a straight line. No wind, blindfolded, no sun (nor waves), without being able to hear anything, and with a guide to protect you. The speed isn't important. Getting it right is, for example by never exceeding the angle of (an impressive) 5 degrees.

.

 
julesies
1044647.  Mon Dec 30, 2013 2:31 pm Reply with quote

Lots of bacteria can do it, too.

 
Spud McLaren
1044681.  Mon Dec 30, 2013 6:22 pm Reply with quote

Back to post 1044493 for a moment - interesting that a change of hemisphere throws the ability. It would seem to indicate that you're reacting to some aspect of the intensity of the magnetic field rather than its orientation. It doesn't matter which hemisphere you're in; the red half of a compass needle that points north in the northern hemisphere will still point north in the southern hemisphere. So I wonder what caused your orientation to reverse?

 
Leith
1044722.  Mon Dec 30, 2013 9:22 pm Reply with quote

Spud McLaren wrote:
Back to post 1044493 for a moment - interesting that a change of hemisphere throws the ability. It would seem to indicate that you're reacting to some aspect of the intensity of the magnetic field rather than its orientation. It doesn't matter which hemisphere you're in; the red half of a compass needle that points north in the northern hemisphere will still point north in the southern hemisphere. So I wonder what caused your orientation to reverse?


Perhaps not intensity, but inclination - the verticle angle at which the earth's magnetic field points into the ground (northern hemisphere) or out of it (southern hemisphere).

This study (mentioned on the QI J series) prompted the scientist behind it to speculate that foxes may use magnetic inclination as a range-finding device to help them pounce on hidden prey:
Discover Magazine: Foxes use the Earth's magnetic field as a targeting system

mis wrote:
The other interesting point... when I went to Singapore for several
weeks I could not detect either north or south at all.. results were
always varying.

My hypothesis is I can detect the closest magnetic pole and from that I
can extrapolate my position in the world. This is further proved by the
fact when I was in Brisbane my error rate (how far from correct I
was/the error deviation) was greater than it was in Melbourne, and that
was larger than when I was in the UK....


Here are some details of the Earth's magnetic field in London, and at the locations you specifically mention (data from http://magnetic-declination.com/*):

London
Magnetic declination: -1 8' WEST
Declination is NEGATIVE
Inclination: 66 27'
Magnetic field strength: 48695.1 nT

Singapore
Magnetic declination: 0 13' EAST
Declination is POSITIVE
Inclination: -14 56'
Magnetic field strength: 42114.2 nT

Brisbane
Magnetic declination: 10 58' EAST
Declination is POSITIVE
Inclination: -57 27'
Magnetic field strength: 53146.8 nT

Melbourne
Magnetic declination: 11 38' EAST
Declination is POSITIVE
Inclination: -68 49'
Magnetic field strength: 60039.7 nT

If you were able to subconsciously 'visualize' where a magnetic field line passing through you hit the ground, based on its horizontal and vertical orientation, that would give you a pretty good sense of north in the UK, but one that would be:
- reflected and a little out in Melbourne
- reflected and further out in Brisbane
- rather confused in Singapore

* Incidentally, magnetic declination, for those not familiar, is the difference between magnetic north and true north, which can vary quite considerably around the globe.

 
mis
1044754.  Tue Dec 31, 2013 6:28 am Reply with quote

Quote:
If you were able to subconsciously 'visualize' where a magnetic field line passing through you hit the ground, based on its horizontal and vertical orientation, that would give you a pretty good sense of north in the UK, but one that would be:
- reflected and a little out in Melbourne
- reflected and further out in Brisbane
- rather confused in Singapore


Which was exactly what I experienced.

I cannot visualise the pole/field, what I have to do is visualise my point of reference (my mothers kitchen, in Gt Yarmouth) and then turn slowly until the visualisation "locks on" to the turning.. when that happens I know where north is, I turn until I can point directly at the corner of my mothers pantry from the centre of the kitchen.

... and yes as a SCUBA diver, I have had to swim in straight lines with no references (at 40m below you can't even see the surface) for the first couple of years in Australia I nearly always swam the exact wrong way (much to the annoyance of my friend who was an instructor and boat hand.) After the first two years and I learned to trust the opposite I amazed people I took diving by my ability to swim dead straight and return to the surface within 5 meters of where I was supposed to be...

 

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