Saturday, March 17, 2007

Emu Hide and Seek and Naturally Occurring Magnetic Particles in Beaks

Emmie the Emu
Being starved for bird company and the chance to try and figure out why they do what they do, I've nine birds at home and none here, I decided to go and visit Emmie today.
Now I've been attempting to win Emmie over but this bird is no sucker. I've come bearing tasty chopped Romaine lettuce, bitty carrots, last time I even brought giant meal worms.
Forget it.
Emmie is having none of it.
When I appear for a visit he struts off in the opposite direction, neck crooked towards the rear onto his back and head crooked forward in the direction in which he's going. Off he goes sometimes at a coquettish trot, only to peep out from behind his emu house or a tree.

I've read that Emus are extremely curious, so today I've decided not to pay the least bit of attention to him and pay attention to everything else I can think of.
I puttered around. Took photographs of rocks, farm machinery, distant grain elevators. Worked the mud out of the treads of my shoes with a stick. Unwrapped gum and put it in my mouth. Whistled Who's Afraid Of The Big Bad Wolf, thumpity, thump. I hear emu feet.
I look at Emmie who may be pretending to be a bush, neck crooked, blending in while still being able to see just what it is I am up to.
Okay what now?
I make sure the camera is ready, quickly scuttle over, trying to skirt the mud, and scrunch behind a very short evergreen. Camera up. Emmie's head pops up. Click. Gotcha.

Emmie the Emu as a bush.
Has Emmie the Emu been attempting to get me to play a game of Emu hide and seek? I walk right at an angle toward Emmie. He walks left and goes behind his emu house. I go behind a fat tree.
When I peek out. There he is. Well I assume the rest of him is there. All I can see is one eye, half a forehead and half a beak appearing from the other side of his house.
I disappear behind my tree, then skitter over toward a new one, slipping in the mud and going down.
After getting back to my feet disgusted at the condition of my clothes, I remember Emmie. He has come out from behind his house as this obviously is something not to be missed. He is standing stock still next to a tree trunk looking through the wire at me with one eye. (first photo)
Now the question becomes, am I actually winning him over the least little bit or does he really think I think he's a tree?
Neither, I'm betting he's hoping against hope, that I'll take another header into the mud.
Donegal Browne


After trying to figure out just exactly how they do it for hundreds of years. Humans may have finally figured out at least part of why Homing Pigeons can find their way home so unerringly!

Many thanks to Kentaurian, long time hawk watcher and science guy, who sent in the fascinating news.

Do homing pigeons really have a natural three axis magnetometer in their beaks?

(Yes, I know the bird above is not a pigeon; it's Doorstep Dove. She's standing-in as I couldn't find a pigeon today. But she and many other birds may well have a magnetic triangulating system as well.) Published: 11 hours ago, 11:23 EST, March 14, 2007 Study:

Iron minerals in birds' beaks may serve as a magnetometer. It has long been recognized that birds possess the ability to use the Earth’s magnetic field for their navigation, although just how this is done has not yet been clarified. However, the discovery of iron-containing structures in the bills of homing pigeons in a new study by Gerta Fleissner and her colleagues at the University of Frankfurt offers a promising insight into this complex topic.

The article will be published online mid-March in Springer’s journal _Naturwissenschaften_. In histological and physicochemical examinations in collaboration with HASYLAB, the synchrotron laboratories based in Hamburg, Germany, iron-containing subcellular particles of maghemite and magnetite were found in sensory dendrites of the skin lining the upper beak of homing pigeons.

A dendrite is a branched extension a nerve cell (neuron). This research project found that these dendrites are arranged in a complex three-dimensional pattern with different spatial orientation designed to analyze the three components of the magnetic field vector separately. They react to the Earth's external magnetic field in a very sensitive and specific manner, thus acting as a three-axis magnetometer. The study suggests that the birds sense the magnetic field independent of their motion and posture and thus can identify their geographical position. The researchers further believe that this ability is not unique to homing pigeons as they expect that the ˜pigeon-type receptor system might turn out to be a universal feature of all birds.

Equally, this concept might not only exclusively apply to birds, since it has been shown that many animals display behavior that is modified or controlled by the Earth magnetic field. The meaning of these minute iron oxide crystals goes farther than their amazing ability to help pigeons home. Research into how they work has caught the interest of nanotechnologists concerning their potential application for accurate drug targeting and even as a data storage device.

The main problem, however, lies in their synthetic production. According to Gerta Fleissner and her colleagues, "Even though birds have been producing these particles for millions of years, the main problem for scientists who want to find benefits from their use will be the technical production of these particles".

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