X-ray spectroscopy supports the hypothesis of how pigeons find their way home

It has long been believed that birds can in some way use the natural magnetism of the earth to navigate. Recently, scientists from the University of Frankfurt employed micro X-ray fluorescence as well as micro XAFS spectroscopy to analyze the skin of the upper beak of homing pigeons. Within the skin lining, they established the existence of tiny maghemite (g-Fe₂O₃) and magnetite (Fe₃O₄) particles (with a ratio of around 9:1) in the dendritic nerve branches that were arranged in a 3D pattern. According to the research team, this strongly supports the theory that the upper beak of pigeons houses a highly sensitive magneto-receptor that can be used for navigation. The experiments were done with synchrotron X-rays at HASYLAB in Hamburg, Germany. For more information, see the paper, "A novel concept of Fe-mineral-based magnetoreception: histological and physicochemical data from the upper beak of homing pigeons", G. Fleissner et al., Naturwissenschaften, published online in mid-March, 2007.