Research Guides




The navigational abilities of night-migratory songbirds, travelling alone over thousands of kilometres, are absolutely staggering. The successful completion of these magnificent voyages depends crucially on the birds’ ability to sense the Earth’s magnetic field. Exactly how this magnetic sense works is largely a mystery: the experimental evidence suggests something extraordinary. The birds’ magnetic compass sensor seems to rely on coherent quantum phenomena that indirectly allow magnetic interactions a million times smaller than kBT (Boltzmann’s constant multiplied by temperature) to be detected in biological tissue. Together with our collaborators, we aim to discover the detailed mechanism of animal magnetoreception.
The primary magnetoreceptor is believed to be cryptochrome, a blue-light photoreceptor protein found in a variety of cell types in the avian retina. Photo-induced electron transfer within the protein produces pairs of radicals in which the unpaired electron spins are in a coherent superposition, far removed from equilibrium. As a consequence, and because the radical recombination reactions conserve spin, weak magnetic interactions can affect the yield of a conformation of the protein that could act as a signalling state.

For more information, see our recent review: Hore & Mouritsen, Ann. Rev. Biophys. 45 (2016) 299-344, which includes a tutorial on the radical pair mechanism.

Research grants
Quantum effects in magnetoreception. DARPA, QuBE program. 2010-2014.
ChemNav – Magnetic sensing by molecules, birds and devices. ERC Advanced Grant. 2013-2018.
Cryptochrome-based magnetic sensing. AFOSR. 2014-2019.
Magnetic field effects on Drosophila melanogaster cryptochrome. EMF Biological Research Trust. 2015-2019.
QuantumBirds   Radical pair-based magnetic sensing in migratory birds. ERC Synergy Grant. 2019-2025.

Current collaborators
Christiane Timmel, Stuart Mackenzie, David Manolopoulos, Justin Benesch (Department of Chemistry, Oxford)
Henrik Mouritsen, Karl-Wilhelm Koch (University of Oldenburg)
Stefan Weber, Erik Schleicher (University of Freiburg)
Leslie Dutton, Christopher Moser (University of Pennsylvania, Philadelphia)
Ilia Solov'yov (University of Southern Denmark, Odense)

Selected Publications

A complete list of publications can be found here.

Magnetocarcinogenesis: is there a mechanism for carcinogenic effects of weak magnetic fields? J. Juutilainen, M. Herrala, J. Luukkonen, J. Naarala and P. J. Hore. Proc. Roy. Soc. B, (2018).

A DNA-based magnetic sensor. P. J. Hore. ACS Cent. Sci., 4 (2018) 318-320.

A light-dependent magnetoreception mechanism insensitive to light intensity and polarization. S. Worster, H. Mouritsen and P. J. Hore. J. Roy. Soc. Interface 14 (2017) 20170405.

Disruption of magnetic compass orientation in migratory birds by radiofrequency electromagnetic fields. H. G. Hiscock, H. Mouritsen, D. E. Manolopoulos and P. J. Hore. Biophys. J. 113 (2017) 1475–1484.

The sensitivity of a radical pair compass magnetoreceptor can be significantly amplified by radical scavengers. D. R. Kattnig and P. J. Hore. Sci. Rep. 7 (2017) 11640.

Millitesla magnetic field effects on the photocycle of an animal cryptochrome. D. M. W. Sheppard, J. Li, K. B. Henbest, S. R. T. Neil, K. Maeda, J. Storey, E. Schleicher, T. Biskup, R. Rodriguez, S. Weber, P. J. Hore, C. R. Timmel, and S. R. Mackenzie. Sci. Rep. 7 (2017) 42228.

Engineering an artificial flavoprotein magnetosensor. C. Bialas, L. E. Jarocha, K. B. Henbest, T. M. Zollitsch, G. Kodali, C. R. Timmel, S. R. Mackenzie, P. L. Dutton, C. C. Moser, and P. J. Hore. J. Amer. Chem. Soc., 138 (2016) 16584-16587.

Floquet theory of radical pairs in radiofrequency magnetic fields. H. G. Hiscock, D. R. Kattnig, D. E. Manolopoulos and P. J. Hore. J. Chem. Phys., 145 (2016) 124117.

Electron spin relaxation can enhance the performance of a cryptochrome-based magnetic compass sensor. D. R. Kattnig, J. K. Sowa, I. A. Solov'yov and P. J. Hore. New J. Phys., 18 (2016) 063007.

Magnetoelectroluminescence in organic light emitting diodes. J. E. Lawrence, A. M. Lewis, D. E. Manolopoulos and P. J. Hore. J. Chem. Phys. 144 (2016) 214109.

The radical-pair mechanism of magnetoreception. P. J. Hore and H. Mouritsen. Annu. Rev. Biophys., 45 (2016) 299-344.

Electron spin relaxation in cryptochrome-based magnetoreception. D. R. Kattnig, I. A. Solov'yov and P. J. Hore. Phys. Chem. Chem. Phys., 18 (2016) 12443-12456.

Weak broadband electromagnetic fields are more disruptive to magnetic compass orientation in a night-migratory songbird (Erithacus rubecula) than strong narrow-band fields. S. Schwarze, N.-L. Schneider, T. Reichl, D. Dreyer, N. Lefeldt, S. Engels, N. Baker, P. J. Hore and H. Mouritsen. Front. Behav. Neurosci., 10 (2016) 55.

The quantum needle of the avian magnetic compass. H. G. Hiscock, S. Worster, D. R. Kattnig, C. Steers, Y. Jin, D. E. Manolopoulos, H. Mouritsen and P. J. Hore. Proc. Natl. Acad. Sci. USA, 113 (2016) 4634-4639.

Chemical amplification of magnetic field effects relevant to avian magnetoreception. D. R. Kattnig, E. W. Evans, V. Déjean, C. A. Dodson, M. I. Wallace, S. R. Mackenzie, C. R. Timmel and P. J. Hore. Nature Chem., 8 (2016) 384-391. 

Anthropogenic electromagnetic noise disrupts magnetic compass orientation in a migratory bird. S. Engels, N.-L. Schneider, N. Lefeldt, C. M. Hein, M. Zapka, A. Michalik, D. Elbers, A. Kittel, P. J. Hore and H. Mouritsen. Nature. 509 (2014) 353-356.

Chemical compass model of avian magnetoreception. K. Maeda, K. B. Henbest, F. Cintolesi, I. Kuprov, C. T. Rodgers, P. A. Liddell, D. Gust, C. R. Timmel and P. J. Hore. Nature, 453 (2008) 387-390.


The Quantum Robin

A Quantum Needle in a Haystack

A Conversation with Peter Hore. M. Peplow, ACS Central Science, 3 (2017) 363-363.

NMR textbooks


Professor P.J. Hore

Physical & Theoretical Chemistry

Telephone: 44 (0) 1865 275 415

Research Group Website