Publications de Richard Marie Servajean

Impact of complex spatial population structure on early and long-term adaptation in rugged fitness landscapes

Anne-Florence Raphaëlle Bitbol, Richard Marie Servajean

We study how rugged fitness landscapes are explored by spatially structured populations with demes on the nodes of a graph, connected by migrations. In the weak mutation and rare migration regime, we find that, in most landscapes, migration asymmetries ass ...

Oxford University Press (OUP)2025

Impact of spatial structure and finite size on the evolution and ecology of asexual microbial populations

Richard Marie Servajean

Evolution is the process by which organisms are modified over time. The fundamental mechanisms underlying evolution are mutations, natural selection and genetic drift. While natural selection favors fitter individuals, genetic drift, which arises from fini ...

EPFL2024

Interactions between pili affect the outcome of bacterial competition driven by the type VI secretion system

Melanie Blokesch, Anne-Florence Raphaëlle Bitbol, Alexandre Lemopoulos, Simon Bernhard Otto, Richard Marie Servajean

The bacterial type VI secretion system (T6SS) is a widespread, kin-discriminatory weapon capable of shaping microbial communities. Due to the system’s dependency on contact, cellular interactions can lead to either competition or kin protection. Cell-to-ce ...

2024

Impact of population size on early adaptation in rugged fitness landscapes

Anne-Florence Raphaëlle Bitbol, Richard Marie Servajean

Owing to stochastic fluctuations arising from finite population size, known as genetic drift, the ability of a population to explore a rugged fitness landscape depends on its size. In the weak mutation regime, while the mean steady-state fitness increases ...

ROYAL SOC2023