Biometals

, Volume 13, Issue 4, pp 325–331

Superparamagnetic Magnetite in the Upper Beak Tissue of Homing Pigeons

  • Marianne Hanzlik
  • Christoph Heunemann
  • Elke Holtkamp-Rötzler
  • Michael Winklhofer
  • Nikolai Petersen
  • Gerta Fleissner
Article

DOI: 10.1023/A:1009214526685

Cite this article as:
Hanzlik, M., Heunemann, C., Holtkamp-Rötzler, E. et al. Biometals (2000) 13: 325. doi:10.1023/A:1009214526685

Abstract

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 nm). The particles form clusters of 1–3 μm diameter, which are arranged in distinct coherent elongated structures, associated with nervous tissue and located between fat cells. Complementary low-temperature magnetic measurements confirm the microscopic observations of fine-grained superparamagnetic particles in the tissue. Neither electron-microscopic nor magnetic measurements revealed any single-domain magnetite in the upper-beak skin tissue.

homing pigeonmagnetoreceptionSAED analysisSQUID magnetometerZFC-FC curves

Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Marianne Hanzlik
    • 1
  • Christoph Heunemann
    • 1
  • Elke Holtkamp-Rötzler
    • 2
  • Michael Winklhofer
    • 1
  • Nikolai Petersen
    • 1
  • Gerta Fleissner
    • 2
  1. 1.Institut für Allgemeine und Angewandte GeophysikLudwig-Maximilians-UniversitätMunichGermany
  2. 2.Zoologisches InstitutJohann-Wolfgang-Goethe-UniversitätFrankfurt a. M.Germany