Description du sujet de thèse

In many perennial plant species, fruit production intensity shows strong year-to-year variation, often synchronized across populations. This reproductive strategy, known as masting, represents both a major ecological and economic issue for forest trees, while remaining an evolutionary puzzle. Masting strongly influences forest regeneration, as well as the demography and evolution of seed-consuming animal species, triggering cascading effects on community dynamics and overall forest ecosystem functioning. Understanding the mechanisms driving masting and its evolutionary causes is essential for predicting how climate change will impact fruiting dynamics and forest regeneration. Oaks are a key group in this regard: their masting mechanisms are particularly complex, and they play a central role in temperate forest ecosystems. In oaks, annual flowering effort fluctuates strongly and largely determines acorn production variability.
This PhD project aims to achieve three main objectives: (i) Identify, using empirical data, the determinants of floral induction and flowering effort; (ii) Develop an evolutionary model of masting based on strategies of floral induction and resource allocation to flowering; (iii) Explore scenarios of masting dynamics and oak regeneration success (including acorn predation by insects) under climate change conditions.
Profile:
Required degree: Master's (M2) in Ecology and Evolution - Specialization: Modeling in ecology and evolution, theoretical ecology
Expected skills:
- Statistical analysis
- Mathematical and numerical modeling
- Scientific writing (reports, articles)
- Ability to lead meetings and ensure quality of tools and results
Knowledge:
- Data collection, analysis, and processing
- English proficiency (B2-C1)
- Applied computing skills
- Strong background in evolutionary ecology
Personal qualities:
- Critical thinking and synthesis skills
- Teamwork and autonomy

Contexte de travail

The PhD candidate will join the Laboratoire de Biométrie et Biologie Évolutive (UMR 5558, Université Lyon 1), located on the LyonTech La Doua campus (Villeurbanne, France). The thesis will be co-supervised by S. Venner (Univ Lyon 1) and N. Delpierre (Univ. Paris-Saclay) and will also be co-supervised by M.-C. Bel-Venner (UCBL) and Vincent Boulanger (ONF). The doctoral student will work within the Quantitative and Evolutionary Ecology of Communities team and interact with its members. The modeling work will also involve collaborations with researchers from CEFE (Montpellier), BIOGECO (Bordeaux), and forest management partners (ONF).
Our little extras:
• A stimulating work environment in contact with research staff
• Professional support with internal training at the laboratory
• The possibility of teleworking
• A company restaurant offering lunch at an attractive price.
• Partial reimbursement of transportation costs (75%)
+ sustainable mobility allowance of up to €300/year
• A site accessible by public transportation (Tram T1 + T4 + bus)
• 44 days of vacation/RTT per year
• Financial contribution to health insurance costs

Contraintes et risques

No major constraints. The thesis will rely primarily on the analysis of existing datasets (from monitoring networks covering 15 and 29 sites in metropolitan France since 2012 and 2018, respectively). Preliminary versions of the mathematical and numerical models are already available; the candidate will develop new modules. Occasional participation in field sampling campaigns and laboratory sample processing is expected.