The overall goal of my research is to gain an understanding of the neural basis of adaptive behaviour; not only as descriptions of particular mechanisms but also with a notion of what constraints (ecological, evolutionary) determine those mechanisms. This has relevance in the context of predicting grasshopper survival and dispersal in the prairies during periods of global warming, as well as in a basic understanding of phenotypic plasticity of nervous systems. For the next grant period I intend to concentrate on two locust behaviours that it would be vital to protect against failure in harsh environments: ventilation and predator evasion.
NSERC Discovery grant summary:
Variation in environmental conditions, such as ambient temperature and oxygen levels, can have dramatic consequences for the operation of the nervous system, which thus endangers animals. For those animals that actively negotiate their environments this occurs at the point when vital neuronal circuits are impaired, long before cells and tissues suffer direct damage. For example, even marginally impaired operation of the neural circuitry for detecting the rapidly looming approach of predators will increase the risk that an organism fails to escape capture and consumption. Also it is important to ensure that the neural circuit responsible for providing working muscles with an adequate oxygen supply continues to operate effectively.
My research program is concerned with discovering the mechanisms by which nervous systems fail under extreme conditions and those that allow some animals to continue behaving in the same environment.
We use the African migratory locust as a model system for our studies because these animals are regularly exposed to high temperatures and, in different seasons, the risk of flooding and immersion. Locusts, and most other insects, have the ability to survive stressful times by entering a coma during which energy is conserved and from which recovery is apparently complete.
Over the next five years (2009-2014) we will describe some of the pathways and processes by which this is achieved and investigate how nervous system function is modified for more efficient operation after recovering from the coma. One idea of general interest to all neuroscientists is that nervous systems are tuned for optimal performance in a process whereby there is a continuous trade-off between high performance and energy conservation. Also the neural shutdown during the coma is very similar to the processes underlying dysfunctions of the mammalian nervous system including stroke and migraine. Understanding how neural tissue copes with stress is important at the level of operation but also in consideration of how populations might be affected by climate change; particularly important for pest species such as locusts and grasshoppers.
Whereas my current focus is on the projects outlined above I have continuing interests in the neuronal control of locust flight manoeuvres (e.g. avoidance steering) and in the mechanisms of the central pattern generator for locust flight. Potential trainees with specific interests in these areas should contact me.