Visual stimuli induced by self-motion and object-motion modify odour-guided flight of male moths (Manduca sexta L.).
Animals rely on multimodal sensory integration for proper orientation within their environment. For example, odour-guided behaviours often require appropriate integration of concurrent visual cues. To gain a further understanding of mechanisms underlying sensory integration in odour-guided behaviour, our study examined the effects of visual stimuli induced by self-motion and object-motion on odour-guided flight in male M. sexta. By placing stationary objects (pillars) on either side of a female pheromone plume, moths produced self-induced visual motion during odour-guided flight. These flights showed a reduction in both ground and flight speeds and inter-turn interval when compared with flight tracks without stationary objects. Presentation of an approaching 20 cm disc, to simulate object-motion, resulted in interrupted odour-guided flight and changes in flight direction away from the pheromone source. Modifications of odour-guided flight behaviour in the presence of stationary objects suggest that visual information, in conjunction with olfactory cues, can be used to control the rate of counter-turning. We suggest that the behavioural responses to visual stimuli induced by object-motion indicate the presence of a neural circuit that relays visual information to initiate escape responses. These behavioural responses also suggest the presence of a sensory conflict requiring a trade-off between olfactory and visually driven behaviours. The mechanisms underlying olfactory and visual integration are discussed in the context of these behavioural responses.
Department of Biology, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E2.
Remko
R
Verspui
John R
JR
Gray
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D003463:Cues; D005260:Female; D005426:Flight, Animal / Q000502:physiology*; D008297:Male; D018402:Manduca / Q000502:physiology*; D009038:Motion; D009039:Motion Perception / Q000502:physiology*; D009812:Odorants; D009949:Orientation / Q000502:physiology*; D012903:Smell / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*