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Current position
Fellow, Visual Sciences, RSB
Research interests
The overarching framework which binds the different facets of my work lies in the desire to understand the mechanisms of decision making that are evident in the behaviour and strategies exhibited in the daily life of animals. I am particularly interested in the way in which sensory systems and sensory processing influence and shape animal behaviour. Several projects in which I am involved are briefly described below.
- Colour vision in marsupials: In this project we are describing marsupial colour vision. Using behavioural, physiological and anatomical methods, we are currently exploring the perception of colour in the tammar wallaby. Unlike most mammals some marsupials appear to have trichromatic colour vision (that means they have three different spectral channels similar to some primates). However, it is yet unclear where the third spectral sensitivity comes from. Project collaborators: Wiebke Ebeling, Jan Provis, Riccardo Natoli.
- visual ecology Visual ecology of fiddler crabs: This is a large, collaborative project that aims to define the visual processing requirements the crabs face in their daily struggle for life. We address a variety of questions that include, intra-specific signaling (colour and motion), burrow defence and predator avoidance. One of the main questions we are currently working on is how the crabs need to organize their anti-predator responses given that they have only incomplete sensory information about the location and direction of movement of predatory birds. In the effort to answer this question, we simultaneously measure, in the crabs' natural habitat, their behavioural response together with the detailed sensory information they have available during predation events. Project collaborators: Tobias Merkle, Ali Alkaladi, Martin How, Jochen Smolka, Jochen Zeil.
- Motion signals: Motion signals: Motion signals are poorly understood because they are both difficult to describe and difficult to manipulate in animals. In this area of research I collaborate with others in two projects. Martin How is endeavoring to determine the structure of fiddler crab waving. Richard Peters is working on the selective pressures that have shaped the structure of an antagonistic motion display in the jacky lizard. Shaun New is working on a basic functional and anatomical description of the jacky's visual system.
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- Flight stabilization and optic flow in insects: In this collaborative project Norbert Boedekker is using high speed video recordings of free flying insects to determine how these insects measure and use optic flow information during flight.
- Plumage colouration in fairy wrens: Male fairy wrens show off their beautiful blue head and cheek patches during their courtship display. By carefully measuring the reflectance of this structural colour under different viewing geometries, we are endeavoring to determine what the actual visual signal is that they present to the females. Project collaborators: Andrew Cockburn, Paul Cooper, Teresa Ward.
Selected Publications
2009
How MJ, Zeil J, Hemmi JM (2009) Variability of a dynamic visual signal: the fiddler crab claw-waving display. Journal of Comparative Physiology A 195 55-67
Zeil J, Boeddeker N, Hemmi JM (2009) Visually Guided Behaviour. In New Encyclopaedia of Neuroscience, ed. Squire LR. Elsevier pp369-380
2008
Detto T, Hemmi JM, Backwell PRY (2008) Colouration and Colour Changes of the Fiddler Crab, Uca capricornis: A Descriptive Study PLoS ONE 3(2): e1629 doi:10.1371/journal.pone.0001629
How MJ, Hemmi JM (2008) Courtship herding in the fiddler crab Uca elegans: Tracking control system Animal Behaviour 76 1259-1265
How MJ, Hemmi JM (2008) Courtship herding in the fiddler crab Uca elegans. Journal of Comparative Physiology A 194 1053-1061
How JM, Hemmi JM, Zeil J, Peters R (2008) Claw waving display changes with receiver distance in fiddler crabs, Uca perplexa. Animal Behaviour 75 1015-1022
Zeil J, Boeddeker N, Hemmi JM (2008) Vision and the Organisation of Behaviour. Current Biology 18 R320–323
Peters R, Hemmi JM, Zeil J (2008) Image motion environments: background noise for movement-based animal signals. Journal of Comparative Physiology A 192 441-456
2007
How MJ, Zeil J, Hemmi JM (2007) Differences in context and function of two distinct waving displays in the fiddler crab, Uca perplexa (Decapoda: Ocypodidae). Behavioral Ecology and Sociobiology 62 137-148
Peters R, Hemmi JM, Zeil J (2007) Signalling against the wind: modifying motion signal structure in response to increased noise. Current Biology 17 1231-1234
Hemmi JM, Zeil J (2007) The Ecology of Information Processing. In Marine Ecology, ed. Connell SD & Gillanders BM, Oxford University Press, Oxford, pp. 441-442
Zeil J, Boeddeker N, Hemmi JM, Stürzl W (2007) Going Wild: Toward an Ecology of Visual Information Processing. In Invertebrate Neurobiology, ed. North G & Greenspan R, Cold Spring Harbor Press, New York. pp. 381-403
2006
Detto T, Backwell PRY, Hemmi JM & Zeil J (2006) Visually mediated species and neighbour recognition in fiddler crabs (Uca mjoebergi and Uca capricornis). Proceedings of the Royal Society of London B, 273, 1661-1666
Hemmi JM, Marshall J, Pix W, Vorobyev M and Zeil J (2006) The variable colours of the fiddler crab Uca vomeris and their relation to background and predation. Journal of Experimental Biology 209, 4140-4153
Zeil J, Hemmi JM & Backwell PRY. (2006) Quick Guide: Fiddler Crabs. Current Biology 16, R40-R41
Zeil J & Hemmi JM (2006) The visual ecology of fiddler crabs. Journal of Comparative Physiology A, 192, 1-25
Vladusich T, Hemmi JM & Zeil J (2006) Honeybee odometry and scent guidance. Journal of Experimental Biology, 209, 1367-1375
2005
Hemmi JM (2005) Predator avoidance in fiddler crabs. 1: Description of behaviour. Animal Behaviour 69, 603-614
Hemmi JM (2005) Predator avoidance in fiddler crabs. 2: The visual cues involved. Animal Behaviour 69, 615-625
Hemmi JM & Zeil J (2005) Fiddler crabs as prey: Sensory-motor abilities and flexibility of behaviour in an arthropod. Marine Ecology Progress Series, 287, 274-278
Vladusich T, Hemmi JM, Srinivasan MV & Zeil J (2005) Interactions of visual odometry and landmark guidance during food search in honeybees. Journal of Experimental Biology, 208, 4123-4135
2003
Hemmi, JM & Zeil J (2003) Robust judgement of inter-object distance by an arthropod. Nature, 421, 160-163
Hemmi, JM & Zeil J (2003) Burrow surveillance in fiddler crabs. 1: Description of behaviour. Journal of Experimental Biology, 206, 3935-3950
Hemmi, JM & Zeil J (2003) Burrow surveillance in fiddler crabs. 2: The sensory cues. Journal of Experimental Biology, 206, 3951-3961
2002
Hemmi, JM, James A & Taylor WRW (2002) Colour opponent retinal ganglion cells in the tammar wallaby retina. Journal of Vision, 2, 608-617
2000
Hemmi JM, Maddess T, Mark RF (2000) Spectral sensitivity of photoreceptors in an Australian marsupial, the tammar wallaby (Macropus eugenii). Vision Research 40: 591-599
1999
Hemmi JM (1999) Dichromatic colour vision in an Australian Marsupial, the tammar wallaby. Journal of Comparative Physiology A, 185, 509-515
Hemmi JM & Grünert U (1999) Distribution of photoreceptor types in the retina of a marsupial, the tammar wallaby (Macropus eugenii). Visual Neurosciences, 16, 291-302.
1998
Hemmi JM & Mark RF (1998) Visual acuity, contrast sensitivity and retinal magnification in a marsupial, the tammar wallaby (Macropus eugenii). Journal of Comparative Physiology A, 183, 379-387
Maddess T, Hemmi JM, James AC (1998) Evidence for spatial aliasing effects in the Y-like cells of the magnocellular visual pathway. Vision Research38: 1843-1859
1995
Hemmi JM & Menzel CR (1995) Foraging strategies of long-tailed macaques, Macaca fascicularis: directionalextrapolation. Animal Behaviour, 49, 457-464
1992
Ward PI, Hemmi JM & Röösli T (1992) Sexual conflict in the dung fly Sepsis cynipsea. Functional Ecology 6: 649-653
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