Pigeons May 'Hear' Magnetic Fields 55
ananyo writes "Individual neurons in birds' brains can relay crucial information about Earth's magnetic field, possibly providing the animals with an 'internal GPS.' Pigeons' remarkable navigational feats have long been pegged to the birds' ability to sense magnetic fields, but pinning down how they do so has frustrated scientists for years. Work published in Science (abstract) shows that individual cells seem to encode information on a magnetic field's direction, intensity and polarity. The work also suggests that these signals come from a part of the inner ear called the lagena, further complicating matters for researchers in the field. The Science paper comes just days after a report in Nature (abstract) revealed that cells in pigeons' upper beaks, previously thought to be magnetoreceptors, are actually immune cells called macrophages."
Re: (Score:2, Funny)
how does it sound?
The same as one hand fwapping.
Re: (Score:3)
There are audio recordings of the rapid changes in the Earth's magnetic field at points on the ground.
http://www.ab9il.net/vlf/vlf1.html [ab9il.net]
Various events also have their own sounds:
http://www-pw.physics.uiowa.edu/mcgreevy/ [uiowa.edu]
Re: (Score:3)
Perhaps that's why pigeons appear to be so fucking stupid; if I had that racket going on in my head all the time all the time all the time voices voices never stopping never stopping in my head never never stopping I'd go a tad scatty.
Shitting on anything that doesn't move is probably the only way to vent their frustration.
Re: (Score:1)
Man, it's been too long since last time I saw a proper old school Slashdot troll. It even uses homosexuality as the point of interest! Refreshing.
Now I just want some hot grits.
I wonder if this is the same case for sea turtles (Score:4, Interesting)
This is just a random wandering thought. If someone is more informed, feel free to enlighten me.
i am more informed (Score:2, Funny)
turtles have been known to vote for obama. they are communists and muslims, and you need to cease with this idealized image of turtle innocence
Re: (Score:3)
My dad's workplace did some research into the accoustics of ocean eater. Ocean water has temperature, pressure, salinity gradients plus different types of wildlife at different latitudes and longitudes. All of these are going to allow creatures to triangulate their location.
It's like penguins that form huge colonies in the icy blizzard region. Navigating by visual landmarks is impossible in a blizzard, so they form a navigation system by constantly calling out.
Re: (Score:2)
No, the ocean does not have pressure gradients - pressure varies with depth and nothing else. Temperature gradients vary wildly with the seasons. Salinity gradients are very weak, and only occur where there are either a) massive inputs of fresh water, or b) massive amounts of evaporation.
So no, none of these will really work to provide navigation cues.
Re: (Score:3)
You can't "mark" a location using magnetic sense - because all a compass gives you is a direction, not a position. (And a not very accurate (relatively speaking) direction at that.) On top of that, the direction varies over time. (See Magnetic Declination [wikipedia.org].)
In school we all get this picture of Earth's magnetic field as a tidy and static system, when in reality it's anythin
There is a position... Just one dimension, though (Score:3)
Magnetic field has different strength in different area so you could (assuming no major changes have occurred) approximate distance from the polar region in addition to knowing the direction. Add to that a landmark or two ("2 days from the shore" or something) and you might actually have relatively good knowledge of where you are. Of course it isn't the exact spot but while I know nothing about sea turtles, I doesn't sound impossible that erring a dozen miles is acceptable and then they just use sound or wh
Re: (Score:2)
No you can't - because field strength does not vary linearly with distance from the polar region. Even if it did, since you can't measure East-West position with a compass - that still wouldn't work to fix a position.
Re: (Score:2)
Re: (Score:3)
If you find and watch the BBC documentary "Richard Hammonds Journey To The Centre of the Planet", he visits a scientist performing experiments with turtles and magnetic fields.
(Specifically, towards the end of part 1 of the 2 parts)
They had a turtle velcroed in a vest so they could anchor it to a swing arm and let it move freely in a tank of water with full control of its flippers. The tank had boards along the outside with coiled wires which could induce a magnetic field.
By flipping the polarity and chang
Inner Ear = Hearing? (Score:5, Informative)
Just because the signals originate in the inner ear, they aren't necessarily audio signals. The semicircular canals in my inner ear don't enable me to 'hear' the local gravity either.
Re:Inner Ear = Hearing? (Score:4, Funny)
Re: (Score:2)
Re: (Score:1)
why do people always have to bring politics into things??
Re: (Score:2)
Earth's magnetic field in space is really the average of all local magnetic fields in the planet. Imagine there were 20+ bar magnets, that sometimes pointed in the same direction and sometimes didn't. The magnetic field follows an inverse cubed law for strength.
Re: (Score:2)
This, (Score:1)
Pretty neat cellular scale compass (Score:2)
I hope we can learn from the observation and shrink our own compass and related technologies. Maybe in a century or so we'll be able to develop cellular implants, drop them on the brain, and see if and how effectively it can learn to interpret the signals.
On that note, I hope we someday figure out that an organism can directly sense something we didn't previously observe or predict. Today I doubt our capabilities and understanding are developed enough to figure that out, even if it is quite commonplace. Nat
pigeon repellent? (Score:5, Interesting)
I wonder if this could lead to a magnetic alternative to the netting that's used to keep pigeon's off of balconies?
Some sort of a device that produces a magnetic field that pigeons find unpleasant...
Re: (Score:1)
All I see now is a pile of frothing, flopping pigeons.
Re:I thought this was common knowledge (Score:4, Insightful)
It is common knowledge. How it works is not.
Dark Tower creepiness (Score:2, Offtopic)
Kinda reminds me of Roland following the lines in the Dark Tower series... creepy.
And vastly off topic.
-1 OT
Geomagnetic reversal (Score:1)
Re:Geomagnetic reversal (Score:4, Insightful)
Since pigeons seem to have been around for at least 23 million years [avianweb.com], during which perhaps 40-50 pole reversals have occurred (according to the wikipedia article), they probably have some evolutionary method of dealing with it...
Re: (Score:2)
Last I heard the expectation was that a magnetic reversal would take something like a century and that during which time the field would not just disappear and then reappear in the other polarity, but instead do something more akin to the poles wandering around and ending up near the opposite spin pole from their former location. While the field strength might vary substantially as well, we wouldn't be completely without a direction-indicating field (though we might have east and west poles for a while and
Pidgin sounds funny (Score:1)
but I didn't know it had ears of its own.
Great story!
GPS? (Score:2)
You mean compass.
Re: (Score:2)
You mean compass.
Newp, they most definitely mean, GPS. A compass will only provide limited
directional data. GPS provides 3d data. Direction, intensity and polarity
would suffice for 3d positioning, ala GPS.
-AI
Re: (Score:2)
Newp, they most definitely mean, GPS. A compass will only provide limited directional data. GPS provides 3d data. Direction, intensity and polarity would suffice for 3d positioning, ala GPS.
Humans have long used a compass-like device called a "diping needle", "dip needle" [kenyon.edu], or "dip circle" [wikipedia.org] to get a reading of "magnetic latitude" by measuring the angle of the earth's field relative to a horizontal plane.
Inner ears have three-axis linear and three-axis rotational accelerometers. It would hardly be surprising
Signs of electromagnetic smog (Score:1)
So what... (Score:2)
Humans hear Magnetic fields [wikipedia.org] all the time.
Birds sixth sense (Score:1)
Not News (Score:2)
Re: (Score:2)
This might explain something else about pigeons (Score:2)
Not only does it explain how they get home, but also why they're in such a rush to do so. If someone were playing Jean Michel Jarre at me I'd do my best to get home as quick as I could too.
Probably not hearing (Score:1)
Just because the sense organ is in the ear doesn't mean that it is associated with the sense of hearing, just like our sense of balance comes from structures in the ear, but that sense is unconnected to hearing.
It's in the inner ear, so it must be hearing! (Score:2)
Just the same way we hear changes in bodily orientation, thanks to the semicircular canals, which are in the inner ear.
I hear a kind of saxophone sound when spinning left about my vertical axis; in the opposite direction it takes on more of a clarinet tone.