Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Magnetite defines a vertebrate magnetoreceptor


The key behavioural, physiological and anatomical components of a magnetite-based magnetic sense have been demonstrated in rainbow trout (Oncorhynchus mykiss )1. Candidate receptor cells located within a discrete sub-layer of the olfactory lamellae contained iron-rich crystals that were similar in size and shape to magnetite crystals extracted from salmon1,2. Here we show that these crystals, which mapped to individual receptors using confocal and atomic force microscopy, are magnetic, as they are uniquely associated with dipoles detected by magnetic force microscopy. Analysis of their magnetic properties identifies the crystals as single-domain magnetite. In addition, three-dimensional reconstruction of the candidate receptors using confocal and atomic force microscopy imaging confirm that several magnetic crystals are arranged in a chain of about 1 µm within the receptor, and that the receptor is a multi-lobed single cell. These results are consistent with a magnetite-based detection mechanism2,3, as 1-µm chains of single-domain magnetite crystals are highly suitable for the behavioural and physiological responses to magnetic intensity previously reported in the trout.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Prices vary by article type



Prices may be subject to local taxes which are calculated during checkout

Figure 1: Step-wise increase in the magnification (CLSM autofluorescent images) of the area in the olfactory lamellae where we find magnetic crystals.
Figure 2: Images of magnetic particle(s).
Figure 3: MFM images that show the response of a putative single magnetic particle (within trout tissue) in the presence of an applied field.
Figure 4: MFM image switching-field distribution.
Figure 5: Images of the magnetoreceptor cell.


  1. Walker, M. M. et al. Structure and function of the vertebrate magnetic sense. Nature 390, 371–376 ( 1997).

    Article  CAS  ADS  Google Scholar 

  2. Kirschvink, J. L. & Walker, M. M. in Magnetite Biomineralization and Magnetoreception by Living Organisms: A New Biomagnetism (eds Kirschvink, J. L., Jones, D. S. & MacFadden, B. J.) 243–254 (Plenum, New York, 1985).

    Google Scholar 

  3. Kirschvink, J. L. & Gould, J. L. Biogenic magnetite as a basis for magnetic field detection in animals. Biosystems 13, 181–201 ( 1981).

    Article  CAS  Google Scholar 

  4. Yorke, E. D. A possible magnetic transducer in birds. J. Theor. Biol. 77, 101–105 (1979).

    Article  CAS  Google Scholar 

  5. Yorke, E. D. Sensitivity of pigeons to small magnetic field variations. J. theor. Biol. 89, 533–537 ( 1981).

    Article  CAS  Google Scholar 

  6. Gould, J. L. Magnetic field sensitivity in animals. Ann. Rev. Physiol. 46, 585–598 (1984).

    Article  CAS  ADS  Google Scholar 

  7. Kirschvink, J. L. Biogenic ferrimagnetism: A new biomagnetism, in Biomagnetism (eds Williamson, S. J., Romani, G. L., Kaufman, L. & Modena, I.) 501–531 (Plenum, New York, 1983).

    Chapter  Google Scholar 

  8. Proksch, R. B. et al. Magnetic force microscopy of the submicron magnetic assembly in a magnetotactic bacterium. Appl. Phys. Lett. 66, 2582–2584 (1995).

    Article  CAS  ADS  Google Scholar 

  9. Babcock, K., Dugas, M., Manalis, S. & Elings, V. Magnetic force microscopy. Res. Soc. Symp. Proc. 355, 311 (1995).

    Article  CAS  Google Scholar 

  10. Wittborn, J. et al. Magnetization reversal observation and manipulation of chains of nanoscale magnetic particles using the magnetic force microscope. Nano. Mater. 12, 1149–1152 (1999).

    Article  Google Scholar 

  11. Dunin-Borkowski, R. E. et al. Magnetic microsctructure of magnetotactic bacteria by electron holography. Science 282, 1868– 1870 (1998).

    Article  CAS  ADS  Google Scholar 

  12. Walker, M. M., Quinn, T. P., Kirschvink, J. L. & Groot, C. Production of single-domain magnetite throughout life by sockeye salmon, Oncorhynchus nerka. J. Exp. Biol. 140, 51–63 (1988).

    CAS  PubMed  Google Scholar 

  13. Mann, S., Sparks, N. H. C., Walker, M. M. & Kirschvink, J. L. Ultrastructure, morphology and organization of biogenic magnetite from sockeye salmon, Oncorhynchus nerka; implications for magnetoreception. J. Exp. Biol. 140, 35–49 (1988).

    CAS  PubMed  Google Scholar 

  14. Diaz-Ricci, J. C. & Kirschvink, J. L. Magnetic domain state and coercivity predictions for biogenic greigite (Fe3S 4): A comparison of theory with magnetosome observations. J. Geophys. Res. 97, 17039–17315 (1992).

    ADS  Google Scholar 

  15. Semm, P. & Beason, R. C. Responses to small magnetic field variations by the trigeminal system of the bobolink. Brain Res. Bull. 25, 735–740 ( 1990).

    Article  CAS  Google Scholar 

  16. Walker, M. M. Learned magnetic field discrimination in the yellowfin tuna, Thunnus albacares . J. Comp. Physiol. A 155, 673– 679 (1984).

    Article  Google Scholar 

  17. Walker, M. M. & Bitterman, M. E. Honeybees can be trained to respond to very small changes in geomagnetic field intensity. J. Exp. Biol. 145, 489–494 (1989).

    Google Scholar 

  18. Wiltschko, R. & Wiltschko, W. Magnetic Orientation in Animals. (Springer, Berlin, Heidelberg, New York, 1995).

    Book  Google Scholar 

  19. Gould, J. L., Kirschvink, J. L., Deffeyes, K. S. Bees have magnetic remanence. Science 201, 1026–1028 ( 1978).

    Article  CAS  ADS  Google Scholar 

  20. Lohmann, K. J. Magnetic remanence in the Western Atlantic spiny lobster. J. Exp. Biol. 113, 29–41 ( 1984).

    Google Scholar 

  21. Walker, M. M. On a wing and a vector: A model for magnetic navigation by homing pigeons. J. Theor. Biol. 192, 341– 349 (1998).

    Article  CAS  Google Scholar 

  22. Walker, M. M. Magnetic position determination by homing pigeons. J. Theor. Biol. 197, 271–276 ( 1999).

    Article  CAS  Google Scholar 

  23. Proksch, R. B., Runge, E., Hansma, P. K., Foss, S. & Walsh, B. High field magnetic force microscopy. J. Appl. Phys. 78, 3303–3307 (1995).

    Article  CAS  ADS  Google Scholar 

  24. Liou, S. H. & Yao, Y. D. Development of high coercivity magnetic force microscopy tips. J. Magn. Magn. Mater. 190, 130–134 (1998).

    Article  CAS  ADS  Google Scholar 

Download references


We thank K. Babcock at Digital Imaging for the generous use of the AFM/MFM. The Biological Imaging Research Unit at the School of Medicine, University of Auckland, provided the CLSM and imaging facilities. In addition, we thank S. Edgar, A. Turner, H. Holloway and especially B. Beaumont for their assistance in preparation and viewing samples on the CLSM and transmission electron microscopy. Financial support came from the Marsden Fund and the School of Biological Sciences.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Carol E. Diebel.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Diebel, C., Proksch, R., Green, C. et al. Magnetite defines a vertebrate magnetoreceptor. Nature 406, 299–302 (2000).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing