Pigeons' navigation skill not down to iron-rich beak cells: study

Apr 11, 2012
Pigeon
Pigeon

The theory that pigeons' famous skill at navigation is down to iron-rich nerve cells in their beaks has been disproved by a new study published in Nature.

The study shows that iron-rich cells in the pigeon beak are in fact specialised , called macrophages. This finding, which shatters the established dogma, puts the field back on course as the search for magnetic cells continues.

"The mystery of how animals detect magnetic fields has just got more mysterious" said Dr David Keays who led the study.

Dr Keays continued: "We had hoped to find magnetic , but unexpectedly we found thousands of macrophages, each filled with tiny balls of iron."

Macrophages are a type of white blood cell that play a vital role in defending against infection and re-cycling iron from . They're unlikely to be involved in magnetic sensing as they are not excitable cells and cannot produce which could be registered by neurons and therefore influence the pigeon's behaviour.

Dr Keays's lab, based at the Institute of in Vienna, worked together with Dr Shaw from the University of Western Australia, and Drs Lythgoe and Riegler from the UCL Centre for Advanced Biomedical Imaging in London.

"We employed state-of-the-art imaging techniques to visualise and map the location of iron-filled cells in the pigeon beak" said Dr Mark Lythgoe.

The search for the actual mechanism that allows , and many other animals, to respond to the Earth's magnetic field and navigate around their environment remains an intriguing puzzle to be solved.

"We have no idea how big the puzzle is or what the picture looks like, but today we've been able to remove those pieces that just didn't fit," said Dr Keays.

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More information: 'Clusters of iron-rich cells in the upper beak of pigeons are macrophages not magnetosensitive neurons' is published online in Nature today. DOI: 10.1038/nature11046

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User comments : 11

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kaasinees
0.2 / 5 (25) Apr 11, 2012
Why do the nerve cells have to be magnetic in order to sense magnetic fields?
You solve one dogma and answer it with another.
PPihkala
5 / 5 (1) Apr 11, 2012
I have seen other studies that link magnetic sense to vision. Vision component work is modified by magnetic fields when hit by light.
Bowler_4007
1 / 5 (1) Apr 11, 2012
whoa they described that picture right down to finest detail...

magnetic fields interfere with each other and electrical charges so from the interferance pattern the pigeon can determine its direction of travel, this is completely off the top of my head and i don't even want to bother speculating what creates the magnetic field or electrical charge needed, if the mechanism i suggested is even remotely close
Telekinetic
1 / 5 (1) Apr 11, 2012
Here's an experiment whose results were inconclusive about the presence and function of magnetite in the pigeons. It's still an incredible mystery:

http://www.gps.ca...ulse.pdf
Sean_W
1 / 5 (1) Apr 11, 2012
I have seen other studies that link magnetic sense to vision. Vision component work is modified by magnetic fields when hit by light.


Yes, it was in robins if I remember correctly, a pigment used a property of brief quantum entanglement to (somehow) detect magnetic fields and it was hailed as one of two big examples of possible quantum effects being used in biological systems (the other being in photosynthesis).
pauljpease
3 / 5 (1) Apr 11, 2012
I thought that earth's magnetic fields polarize the light and cells in their retina sense that polarization.
kevinrtrs
1.6 / 5 (7) Apr 12, 2012
A nice poser for evolutionists is just HOW on earth did this ability develop all by itself, as a chance mutation or two? How did it get integrated into the navigation system of pigeons if one component will not work if the other isn't present? That is, if the whole system is irreducibly complex?

I like the brief quantum entanglement idea - it makes it even more impossible to say the navigation system developed by chance!
barakn
3 / 5 (2) Apr 12, 2012
Irreducible complexity is not a valid scientific paradigm. It's used by ignoramuses that are too lazy to come up with a valid argument.
barakn
1 / 5 (1) Apr 12, 2012
I thought that earth's magnetic fields polarize the light and cells in their retina sense that polarization.
While this is theoretically possible, the atmosphere itself polarizes light from the sun, most strongly at an angle ~90 degrees from the sun, for purely geometrical reasons, and this polarization is so strong it overwhelms polarization induced by the magnetic field.
bewertow
3.7 / 5 (3) Apr 12, 2012
A nice poser for evolutionists is just HOW on earth did this ability develop all by itself, as a chance mutation or two? How did it get integrated into the navigation system of pigeons if one component will not work if the other isn't present? That is, if the whole system is irreducibly complex?

I like the brief quantum entanglement idea - it makes it even more impossible to say the navigation system developed by chance!


reported for religious trolling...again...and again...
loligo
not rated yet Apr 20, 2012
Great research!! Great study!!
Finally someone put it right. The retina was always the better model for magnetic perception but the beak theories blocked lots of research founding. I guess this will not be the last artifact uncovered from the Frankfurt magnetic navigation groups. What do we learn out of this? If you do cell biology you better do the right controls before you try to establish a dogma.
Thank´s guys!