David Keays is one of the mega stars of animal navigation research and has spent a life time trying to work out how magnetism might work.
Here is a summary of his latest work:
Magnetoreception is the ability to sense the Earth’s magnetic field, which is used for orientation and navigation.
Behavioural experiments have shown that it is employed by many species across all vertebrate classes; however, our understanding of how magnetic information is processed and integrated within the central nervous system is limited.
In this Commentary, we review the progress in birds and rodents, highlighting the role of the vestibular and trigeminal systems as well as that of the hippocampus. We reflect on the strengths and weaknesses of the methodologies currently at our disposal, the utility of emerging technologies and identify questions that we feel are critical for the advancement of the field.
We expect that magnetic circuits are likely to share anatomical motifs with other senses, which culminates in the formation of spatial maps in telencephalic areas of the brain. Specifically, we predict the existence of spatial cells that encode defined components of the Earth’s magnetic field.
Malkemper, E. P., Nimpf, S., Nordmann, G. C. & Keays, D. A. 2020 Neuronal circuits and the magnetic sense: central questions. The Journal of Experimental Biology223, jeb232371. doi: 10.1242/jeb.232371. Malkemper3 2020