Mother Nature's GPS (TM)

Okay, let's just call it "Mother Nature's GPS." But by whatever name, it seems that researchers have figured out what lets homing pidgeons home in on home.

According to a team led by Gerta Fleissner at the University of Frankfurt, it's not the iron will of the birds to find their way home, but the iron beaks. Scientists have generally known that the birds use the Earth's magnetic field for navigation. What they didn't know was the specifics. According to Dr. Fleissner, those specifics include iron-containing subcellular particles of maghemite and magnetite in sensory nerve cells of the skin that lines the bird's upper beak. And in more detail (perhaps more than you ever expected to hear), the nerve cells are arranged in 3D patterns that react to the Earth's magnetic fields in much the same way as a three-axis magnetometer. (A TAM is a device which measures the Earth's magnetic field, typically in three-dimensional Cartesian space. You then have to transform these measurements into meaningful bearing information.)

Fleissner's research, which is presented in a paper with the catchy title of "A Novel Concept of Fe-mineral-based Magnetoreception: Histological and Physicochemical Data From the Upper Beak of Homing Pigeons," indicates that the homing pidgeons sense the magnetic field independent of their motion and posture, therefore making it possible to identify their geographical position. Jeez, and I usually can't figure out where I am with a GPS device or not.

Posted by Jon Erickson at 12:27 PM  Permalink