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Date | Oct 18, 2024 |
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Speaker | Raoul Gael |

Dept. | Ecole Polytechnique |

Room | 27-325 |

Time | 10:30-11:30 |

We are interested in a population structured by two phenotypic traits : a seed production trait (if the individual produces seeds rapidly), and a dormancy temperature threshold (the individual goes dormant if the temperature goes above this threshold). These traits, together with given meteorological conditions, impact the survival and reproduction ability of individuals.

We propose a detailed mechanistic model, where we detail the life cycle of individuals, and where the reproduction operator is akin to a collision operator in kinetic theory. Using asymptotic limits, and in particular a macroscopic limit, we simplify the model. The main asymptotic limit we use relies on the kinetic reproduction operator to obtain a closed equation on the mean phenotypic traits of the population. The final model is a system of two ordinary differential equations, the solutions of which can be represented in a phase plane. We can then use numerical simulations to analyse the dynamics of that model and use this convenient display of the model solutions to discuss the ecological outcomes of the model. For different meteorological shifts (in precipitations and/or in temperatures), we observe if the population is able to survive and to adapt to the new environmental conditions.

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