Smart vs dumb, predator-experienced vs predator-naive snails: How to change the phenotype.

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Our (HQP and me) proposed program arises from discoveries funded by my previous NSERC grant (48 of the 52 peer-reviewed published papers in that period). Using the Lymnaea model system we developed, we examine biologically important ideas centered on: 1) Behavioural phenotype transformation; 2) Factors modifying (enhancing or impeding) memory formation and retrieval; and 3) Their underlying neuronal basis in a neuron we have shown to be necessary for memory formation. ***In this proposal we ask how: 1) Lymnaea are transformed from a predator-nave state to a population that now recognizes the predator (i.e. how do they become a predator-experienced strain). The problem of invasive species in Canada and how species native and nave adapt is of great biological, ecological and in many cases economic importance; 2) A Lymnaea strain can be transformed into a population possessing differing cognitive abilities. This transformation may be due to genetic drift or targeted gene flow. It may make the animal smarter or dumber (snails that don't make memory easily). It raises the question of the dimensions of evolutionary tradeoffs (i.e. what is gained or lost by becoming smart or dumb); 3) Trauma experienced as a juvenile (e.g. a cracked shell) not only transforms juvenile behaviours but also alters subsequent adult behaviours and possibly even the behaviour of future off-spring; 4) Memory made in smart snails (i.e. snails who make memory faster and better) while made, is obstructed by stress and how stress-reduction then causes the memory to become accessible. Think of not knowing the answer to a question on an exam, but after handing in the exam you now remember it; 5) After experiencing two stimuli simultaneously, one signaling danger and the other a neutral stimulus, the previously neutral stimulus now signals danger. This is a form of higher learning known as configural learning, and is necessary if an animal is to successfully adapt to a changing environment; and 6) The neurophysiological basis for the transformations mentioned above; specifically changes in a neuron, RPeD1 that we have shown to be necessary for memory formation. ***Together the results of answering these questions will enable us to have a much better understanding of the how and why of important, significant behaviours, such as predator awareness and memory formation, that are altered as the Canadian environment changes. The proposed program employs techniques in everyday use in my lab and are mastered by the HQP. The HQP develop into persons able to construct and test worthwhile hypotheses and present their findings in peer-reviewed publications. Based on our past history I am confident that we will successfully answer these questions and be able to effectively communicate the findings appropriately (written and orally) to the scientific community. In addition, the popular media will be interested in many of our findings and thus the lay community will be informed.**