Many insects possess exquisite visual abilities, which they use to perform a number of essential tasks, such as controlling locomotion, locating food sources, or selecting partners. In addition to colour and polarisation, the spatial and temporal information the visual system extracts about an insect’s environment are key to supporting many of these behaviours. A fast flying insect, for example, requires rapid feedback about potential obstacles or course perturbations to ensure a safe flight. The same insect may also need to recognise fine spatial patterns on flower faces that may indicate a rich nectar source. We therefore investigate how such spatial and temporal information is acquired and processed in the visual system of insects, using hawkmoths (Sphingidae) as our model.
Hawkmoths are a family of insects with a unique flight mode: they hover in front of flowers to suckle nectar like hummingbirds – yet are also capable of fast, agile flight manoeuvres. Moreover, a unique behaviour exhibited by the diurnal hummingbird hawkmoth is the use of patterns on flower faces to guide its proboscis to the nectary efficiently. Their particularly high-resolution compound eyes allow for the high spatial acuity required for this task – while many of their nocturnal relatives have invested in high sensitivity, extending their visual ranges into the dark of the night - even down to starlight levels in some species. These fantastic visual abilities, combined with their unique behavioural repertoire, make hawkmoths an excellent neuroethological model. In our group, we therefore characterise the first visual processing layer of their brain, the lamina, anatomically and physiologically. We furthermore investigate their flight control and flower probing, to understand the contributions of spatial and temporal processing to these behaviours.
- (Spatial) information processing in the hawkmoth lamina.
- Spatial acuity of hawkmoth flight control.
- Visual control of proboscis movements during flower probing in the hummingbird hawkmoth.
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