Dr Nicholas Roberts

group: Behaviour, Sensory and Neurobiology
lab: Ecology of Vision, Fish Ecology and Evolution

Academic history

I gained my first degree, an MPhys in Physics and Astrophysics, in 1999 at the University of Manchester. I stayed on in Manchester and completed a PhD in the Liquid Crystal Physics Group with Prof Helen Gleeson in 2003. The focus of my work was on optical studies of model biological liquid crystal systems relating to vertebrate photoreceptors. During my PhD, I conducted much of my biological research at University of Victoria, BC, Canada. After a year as a post-doc back in Manchester, I was awarded a Leverhulme Trust Early Career fellowship to conduct research on vertebrate polarization vision. In 2006, I was awarded an EPSRC Life Science Interface fellowship to work on optical design in vertebrate and invertebrate visual systems, splitting my time between the new Photon Science Institute at Manchester and Queens University in Canada. In Oct 2009, I started a 5 year BBSRC David Philips Fellowship based in the Ecology of Vision Group here at Bristol.

Research

I am primarily interested the detection of light and colour in nature. My research is focused on investigating optical mechanisms that underlie sensory abilities such as polarization vision and the bio-optics of communication and photoreception. My work adopts a broad intra- and inter-disciplinary approach, using a range of physics based techniques, such as laser tweezing, microspectrophotometry and X-ray scattering. Ultimately, I want to understand how visual information helps guide aspects of animal behaviour.

Current research projects include:

Bio-physical mechanisms of polarization vision.
Vision in the deep sea – how photoreceptors work under pressure.
The physiological optics of rods and cones.
Animals that manipulate polarized light.
The evolution of silver reflectors.

Recent publications

Journal

Roberts N.W., Chiou T-H., Marshall N.J. and Cronin T.W. A biological quarter-wave retarder with excellent achromaticity in the visible wavelength region Nature Photonics, 3 641 2009.
Cronin T.W., Chiou T-H., Caldwell R.L., Roberts N.W. and Marshall N.J. Polarization signals in mantis shrimps Proc SPIE 7461 74610C 2009.
Wagner H.-J., Douglas R.H., Frank T.M., Roberts N.W. and Partridge J.C. A novel vertebrate eye using both refractive and reﬂective optics Current Biology 19 108-114 2009.
Grigorenko A. N., Roberts N.W., Dickinson M. R. and Zhang Y. Nanometric optical tweezers based on nanostructured substrates Nature Photonics 2 365 - 370 June 2008.
Roberts N.W., Needham M. A mechanism of polarized light sensitivity in cone photoreceptors of the goldﬁsh Carassius auratus. Biophys J 93 3241-3248 2007.
Jewell S.A., Vukusic P., and Roberts N.W. Circularly polarised colour reﬂection from helicoidal structures in the beetle Plusiotis boucardi. New J. Phys. 9 99 2007.
Roberts N.W. The optics of vertebrate photoreceptors: anisotropy and form birefringence Vision Research 46(19) 3259-3266, 2006.
Grigorenko A.N., Gleeson H.F., Zhang Y., Roberts N.W., Sidorov A.R., and Panteleev A.A. An antisymmetric plasmon resonance in coupled gold nanopar ticles as a sensitive tool for detection of local index of refraction, Appl. Phys. Lett. 88, 124103 2006.
Roberts N.W. and Gleeson H.F. The absorption of polarized light by vertebrate photoreceptors. Vision Research, 44(23), 2643-2652, 2004.
Roberts N.W., Temple S.E., Haimberger T.J., Gleeson H.F. and Hawryshyn C.W. Differences in the optical properties of vertebrate photoreceptor classes leading to axial polarization sensitivity. J. Opt. Soc. Am. A. 21(3), 355-345, 2004.