Table of Contents
Journal of Biophysics
Volume 2009, Article ID 380976, 6 pages
http://dx.doi.org/10.1155/2009/380976
Research Article

Navigation by Induction-Based Magnetoreception in Elasmobranch Fishes

Department of Physics, University of Otago, P.O. Box 56, Dunedin 9016, New Zealand

Received 27 April 2009; Accepted 29 July 2009

Academic Editor: Walter Stühmer

Copyright © 2009 T. C. A. Molteno and W. L. Kennedy. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A quantitative frequency-domain model of induction-based magnetoreception is presented for elasmobranch fishes. We show that orientation with respect to the geomagnetic field can be determined by synchronous detection of electrosensory signals at harmonics of the vestibular frequency. The sensitivity required for this compass-sense mechanism is shown to be less than that known from behavioral experiments. Recent attached-magnet experiments have called into doubt the induction-based mechanism for magnetoreception. We show that the use of attached magnets would interfere with an induction-based mechanism unless relative movement between the electrosensory system and the attached magnet is less than 100  𝜇 m. This suggests that further experiments may be required to eliminate induction as a basis for magnetoreception.