I am an urban evolutionary ecologist whose work focuses primarily on birds. I study how human-altered environments shape animal phenotypes, fitness, natural selection, and welfare.
Using high-resolution satellite imagery, fine-scale GIS habitat characterization, and field data, I investigate how animal phenotypes vary along urbanization gradients, from local habitat variation within cities to continent-scale patterns.
I investigate how urban environments alter natural selection and how selection patterns vary with local environmental conditions, potentially contributing to evolutionary divergence in urban populations.
I investigate how human-dominated environments shape wild animal welfare, and how ecological and behavioral data can help identify welfare-relevant impacts and inform wildlife-inclusive urban policy.
We report reproductive outperformance for paler urban individuals and convergent stabilizing selection on females of both species, while selection patterns in rural populations remain relaxed. By linking plumage coloration to multiple reproductive performance proxies at individual and pair levels, this study provides evidence that natural selection may contribute to the paler carotenoid-based coloration observed in city birds.
Urbanisation is a major driver of environmental change, reshaping ecological and evolutionary processes. Urban-driven phenotypic differences are increasingly documented, but the underlying role of selection is still understudied. One pattern is the consistent reduction of carotenoid-based plumage pigmentation in city birds. Urban carotenoid-based colouration dullness may reflect poorer dietary carotenoid availability and a possible tradeoff between ornamentation and physiological functions. We investigated carotenoid-based plumage colouration covariation with reproductive performance in great tits Parus major and blue tits Cyanistes caeruleus, two passerine species found in urban habitats, with overlapping ecological niches but specific foraging ecology. Using 10 years of data from a pair of urban and rural populations, we tested whether covariations between the yellow ventral feathers carotenoid chroma and three measures of reproductive performance (clutch size, number of offspring fledged, and fledging success) differ between habitats. Our analyses uniquely examines both individual and pair-level data, and test for parallel evolutionary trajectories and habitat-specific selection on carotenoid-based plumage. In both species, carotenoid-based colouration of urban females showed stabilising selection, with counter-selection against highly pigmented individuals. In great tits, urban males exhibited directional pattern favouring duller plumage considering fledging success and opposite urban versus rural tendencies considering the number of fledged offspring. The urban great tit pairs that produced the largest clutches and fledged more offspring consisted of males and females that had less pigmentation than the population average. In contrast, selection patterns in the rural population were relaxed, showing no clear association between pigmentation and reproductive performance in either species. These results match the global trend of reduced carotenoid-based colouration in urban environments, and suggest natural selection may contribute to these divergences. Urban habitats may alter dietary resources, favouring less pigmented plumage as a cost-effective adaptation. These findings invite further investigation both in other coloured traits and across diverse urban and rural populations.
Across six European cities, carotenoid-based plumage coloration declined with increasing impervious surface cover at the territory scale, while brightness and UV coloration showed no comparable relationship. The study provides continent-scale evidence that fine-scale variation in urban habitat structure is associated with phenotypic variation within cities.
Across 11 years of urban/rural data near Paris, urban males and females have larger black ties (“urban melanism”). In urban habitats, males with smaller ties have higher clutch sizes and fledged offspring; older urban females with larger ties show higher fledging success, suggesting possible detox benefits. Rural ornamentation is not linked to performance. Optimal male–female combinations differ by habitat: successful urban pairs combine an average/bigger female tie with a smaller male tie, while rural patterns are weaker. Findings point to sex-specific, context-dependent selection and reduced sexual dimorphism under urbanisation.
RT ParusNet Meeting, Paris, France
British Ornithologists' Union (BOU), Nottingham, UK
British Ornithologists' Union (BOU), Nottingham, UK
ParidMeeting, Montpellier, France
ESEB 2025, Barcelona, Spain
Ecology & Behaviour, Montpellier, France
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Sorbonne Université — 2023–2025
IEES Paris — 2023–2026
