Gaël Raoul Visiting CCIMI

Written by Rachel Furner
April 24, 2017

Gaël Raoul, researcher (Charge de recherche CNRS) at the Centre de Mathematiques Appliquees at the Ecole Polytechnique (Paris), and an associated member of the Centre d’Ecologie Fonctionnelle et Evolutive in Montpellier (Team Evolutionary Ecology and Epidemiology), will be visiting the CCIMI from May 14th-20th.

Gaël works on mathematical models used in ecology and evolutionary biology, and his main interests are;

  • Impact of climate change on species’ range (models for asexual or sexual populations)
  • Impact of evolutionary phenomena on the dynamics of epidemics (gene surfing, resistance to antibiotics…)
  • Models of particles interacting through non-local forces.

On Wednesday 16th May at 2pm Gaël will be presenting the CCIMI seminar;

A macroscopic limit for an ecology model

Abstract:  We are interested in PDE models that are used in evolutionary ecology to investigate the effect of climate change on species’ range. More precisely, we will consider the Spatial Infinitesimal Model, a Kinetic model, and the Kirkpatrick-Barton model, a macroscopic model. Our goal will be to provide a rigorous macroscopic limit between those two models. We will also detail a biological study of the effect of pollen dispersion, where the macroscopic limit mentioned is used.

To describe the macroscopic limit from the Spatial Infinitesimal Model to the Kirkpatrick-Barton model, we take advantage of a Tanaka inequality satisfied by the reproduction operator, combined to parabolic estimates to control the spatial dynamics of the solution. As a by-product of this argument, we obtain estimates on a higher moment of solutions of the kinetic model, provided the reproduction rate is large enough.

The seminar is open to all, to find out more on this, and other CCIMI seminars please visit

If you would like to meet with Gaël Raoul whilst he is here please get in touch with