Superparamagnetic Magnetite in the Upper Beak Tissue of Homing Pigeons

  title={Superparamagnetic Magnetite in the Upper Beak Tissue of Homing Pigeons},
  author={Marianne Hanzlik and Ch Heunemann and Elke Holtkamp-R{\"o}tzler and Michael Winklhofer and Nikolai P. Petersen and Gerta Fleissner},
Homing pigeons have been subject of various studies trying to detect magnetic material which might be involved in magnetic field perception. Here we focus on the upper-beak skin of homing pigeons, a region that has previously been shown to contain nerves sensitive to changes of the ambient magnetic field. We localized Fe3+ concentrations in the subcutis and identified the material by transmission electronmicroscopy (TEM) as aggregates of magnetite nanocrystals (with grain sizes between 1 and 5… 

Hypothetical superparamagnetic magnetometer in a pigeon’s upper beak probably does not work

The results indicate that magnetite clusters, constituted by superparamagnetic nanoparticles and observed in a pigeon’s upper beak, may not be a component of a measuring system providing the magnetic map.

Ultrastructural analysis of a putative magnetoreceptor in the beak of homing pigeons

The subcellular organization of afferent trigeminal terminals in the upper beak of the homing pigeon, Columba livia, which are about 5 μm in diameter and contain superparamagnetic magnetite (SPM) crystals was investigated.

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