Réunion annuelle du RT Théorie et modélisation de la biodiversité

1 déc. 2025, 09:00 → 3 déc. 2025, 17:00 Europe/Paris

Salle de conférences (Bordeaux)

theomodive2025_programme_abstract_book.pdf

timetable.pdf

lun. 1 décembre

13:00 → 13:59 Accueil des participants // Registration & coffee

14:00 → 14:25 Mot de bienvenue // Welcome words

Orateurs: Frédéric Barraquand (CNRS), Guilhem Sommeria-Klein (Centre Inria de l'Université de Bordeaux), Mehdi CHERIF (INRAE)

14:30 → 16:00 Regular talks: Microbial and community ecology

14:30 A quick look at recent microbial macroecology

Orateur: Matthieu Barbier (CIRAD & INTP)

15:00 Challenges in microbial interaction inference from time series

Orateur: Felix Roy (INRAE)

15:30 Emergent coexistence in ecological communities

Orateur: Guim Aguadé-Gorgorió (ISEM Montpellier)

16:00 → 16:30 Coffee break

16:30 → 17:20 Keynote: Elsa Abs (CNRS, LCSE Paris)

Title: Toward an eco-evolutionary modeling framework for the role of microbes in the carbon cycle

Abstract: Soil microbes regulate a major part of the terrestrial carbon cycle, yet their dynamics are rarely represented in a mechanistic — let alone evolutionary — way in global models. In this talk, I will present a framework that combines microbial ecology, adaptive dynamics, and a mechanistic model of the carbon cycle. By linking microbial growth, enzyme allocation, and biogeochemical feedbacks, this model allows us to explore how microbial strategies could evolve under warming, and what consequences this might have for global carbon stocks. I will argue that this approach helps bridge classical evolutionary theory and microbial ecology, as well as phenomenological and process-based modeling perspectives — and discuss what it means to embed evolution explicitly in climate-relevant models.

19:30 → 21:30 Dinner

mar. 2 décembre

09:00 → 09:50 Keynote: Amaury Lambert (ENS, College de France)

Title: Geometry and stability of species complexes

Abstract: Species complexes are groups of closely related populations exchanging genes through migration. We study by a modeling approach the stability and the structure of species complexes in a class of metapopulation models where $N$ demes see their gene pools homogenize as an effect of gene flow and diverge through the local accumulation of neutral or selective substitutions. Importantly, we model the ecological feedback of differentiation on gene flow by assuming that the success of introgressions of foreign alleles increases with genomic similarity, through a specific nondecreasing function $h$. As the target of genomic differentiation gets large, pairwise genomic similarities approximately follow an autonomous system of $N(N-1)/2$ differential equations. We investigate the emergence of non-transitive species structures such as ring species and study the effect of temporary isolation on the species complex. We also show that in large, well-connected metapopulations, species form increasingly coherent and uniform entities, so that the initiation of speciation events requires the existence of idiosyncratic geographic or selective restrictions on gene flow.

09:50 → 10:30 Coffee break

10:30 → 12:00 Regular talks: Biodiversity and ecosystem function

10:30 Beyond biomass: how interactions shape species’ role for ecosystem functioning

Orateur: Alice Ardichvili (SETE)

11:00 Aridity and grazing modulate the multidimensional biodiversity–stability relationships in drylands

Orateur: Benoît Pichon (Isem)

11:30 Partitioning net biodiversity effects on ecosystem resistance and resilience

Orateur: Mario DESALLAIS (Université de Fribourg (Suisse))

12:00 → 14:00 Lunch

14:00 → 15:00 Regular talks: Spatial modelling of ecosystems I

14:00 PATOU, a scalable numerical model for complex spatio-temporal ecosystem dynamics: principles, methods, and first applications

Orateur: François Rincon (IRAP, CNRS)

14:30 A new framework to explore spatial and scale dependency of biodiversity and ecosystems

Orateur: Jules Treton

15:00 → 15:10 Small break

15:10 → 15:40 Regular talks: Coevolution

15:10 Local adaptation of host-parasite coevolution on spatial networks

Orateur: Saismit Naik (ISEM, University of Montpellier, CNRS)

15:50 → 16:15 Coffee break

16:15 → 17:15 Discussion

19:30 → 21:30 Dinner

mer. 3 décembre

09:00 → 09:50 Keynote: Jonathan Rolland (CNRS, CRBE Toulouse)

Title: Conceptual and empirical bridges between micro- and macroevolution

Abstract: Since the beginning of the 20th century and the modern synthesis, evolutionary biology has been divided between microevolution (below the species level) and macroevolution (above the species level). Conceptual frameworks, terminology and mathematical models remain largely separate among those scales, leading to several paradoxes, such as the paradox of stasis. In this talk, I will present some opportunities to unite scales exploring major questions that require bridging the gap between micro and macroevolution: For example: Why does the rate of evolution appear to accelerate close to the present time? Why is there stasis over long evolutionary timescales? Do bursts of phenotypic evolution and speciation occur at the same time? Do ecological interactions leave a predictable signature on macroevolution? I will also present some of the avenues explored in the last years in my research group, mostly related to adaptations across latitudinal clines and species range shifts.

09:50 → 10:30 Coffee break

10:30 → 11:30 Regular talks: Spatial modelling of ecosystems II

10:30 Impact of spatial heterogeneity on biodiversity-yield trade-offs in agricultural landscapes

Orateur: Madeleine Kubasch (iEES, École polytechnique)

11:00 Interaction scales govern self-organized spatial structure and bistability in dryland ecosystems

Orateur: Nathan Humbert (ISEM - Université de Montpellier)

11:30 → 12:00 Conclusion of the meeting

12:00 → 14:00 Lunch