Biology subjects

Ferriere, R.

Publications and source records attributed to Ferriere, R..

6 recordsLinked to original sources

bioRxiv2026

Microbial eco-evolutionary dynamics of decomposition and dormancy

Soil microorganisms regulate a major component of the terrestrial carbon cycle, yet predictions of soil carbon stocks and fluxes often neglect microbial life-history adaptation. To fill this gap, we develop a spatially and stage-structured eco-evolutionary model in which active and dormant microbes move between favorable microsites and an unfavorable bulk soil matrix; decompose organic carbon through costly exoenzyme production; and evolve both exoenzyme investment and entry into dormancy. The model shows that dormancy expands the ecological conditions under which microbial populations persist and has a non-monotonic effect on soil carbon stocks. Adaptive dormancy is shaped by opposing selection in microsites, where inactivity carries an opportunity cost, and in the matrix, where dormancy protects cells from mortality. When dormancy and exoenzyme production jointly evolve, the traits may increase together under high microbial mobility, but often evolve in opposite directions because both carry survival benefits in the matrix. These eco-evolutionary feedbacks can either amplify or attenuate soil carbon fluxes to the atmosphere, depending on soil structure, microbial movement, and dormancy costs. Our results suggest that incorporating microbial life-history evolution into soil carbon models is essential for predicting soil carbon feedbacks to climate.

ecology↗

bioRxiv2026

Spatial heterogeneity shapes microbial eco-evolutionary dynamics of soil carbon

The study of reciprocal influences between ecological and evolutionary processes has advanced considerably, yet integration between evolutionary biology and ecosystem-level ecology remains limited. Here we contribute to this integration by advancing the theory of eco-evolutionary feedbacks between soil microbial adaptation and soil-atmosphere carbon fluxes in a warming climate. We develop a spatially structured model of soil organic matter decomposition that represents microbial populations in microsites embedded in a bulk-soil matrix and focuses on exoenzyme production as a key resource-acquisition trait. The evolutionarily adapted investment in exoenzyme production is shaped by opposing selective forces: negative selection within microsites, where lower-investing mutants exploit exoenzymes as public goods, and positive selection in the soil matrix, where exoenzyme production directly benefits individual cells. Microsite density emerges as a critical determinant of microbial adaptation to warming and its consequences for soil carbon loss. Even small changes in microsite density across a threshold can reverse the ecosystem-level effect of adaptation, from buffering to amplifying carbon loss. High microsite density generally promotes buffering, whereas low microsite density has little effect in cool ecosystems but can strongly amplify carbon loss in warm ecosystems, especially when microbial mobility is low. These results identify soil spatial structure at microsite scale as a key mediator of microbial evolutionary adaptation and soil carbon-climate feedback under global environmental change, with implications for quantitatively improving Earth system models.

ecology↗

bioRxiv2025

Modulation statistics of natural soundscapes

Modulation statistics of "natural soundscapes" were estimated by calculating the modulation power spectrum (MPS) of a database of acoustic samples recorded in nine pristine terrestrial habitats for four moments of the day and two contrasting periods differing in precipitation level. Following Singh and Theunissen (2003), a set of statistics estimating low-pass quality, starriness, separability, asymmetry, modulation depth and [Formula] temporal-modulation power-law relationships were calculated from the MPS of the samples and related to geographical, meteorological factors and diel variations. MPS were found to be generally low-pass in shape in the modulation domain, with most of their modulation power restricted to low temporal (<10-20 Hz) and spectral modulations (<0.5-1 cycles/kHz). Modulation statistics distinguished between habitats irrespective of moment of the day and precipitation period, with a greater role of Modulation depth and Starriness. Separability and Starriness were found to be related to the global biodiversity decrease from tropical to polar regions, suggesting that the lack of joint high spectral and fast temporal modulations, and MPS complexity are important features characterising "biophony", the collective sound produced by animals in a given habitat. These findings may help guide research on monitoring auditory behaviors and underlying mechanisms expected to exploit regularities of natural scenes.

neuroscience↗

bioRxiv2022

Human-environment feedback and the consistency of proenvironmental behaviour

Addressing global environmental crises such as anthropogenic climate change requires the consistent adoption of proenvironmental behavior by a large part of a population. Here, we develop a mathematical model of a simple behavior-environment feedback loop to ask how the individual assessment of the environmental state combines with social interactions to influence the consistent adoption of proenvironmental behavior, and how this feeds back to the perceived environmental state. In this stochastic individual-based model, individuals can switch between two behaviors, active (or actively proenvironmental) and baseline, differing in their perceived cost (higher for the active behavior) and environmental impact (lower for the active behavior). We show that the deterministic dynamics and the stochastic fluctuations of the system can be approximated by ordinary differential equations and a Ornstein-Uhlenbeck type process. By definition, the proenvironmental behavior is adopted consistently when, at population stationary state, its frequency is high and random fluctuations in frequency are small. We find that the combination of social and environmental feedbacks can promote the spread of costly proenvironmental behavior when neither, operating in isolation, would. To be adopted consistently, strong social pressure for proenvironmental action is necessary but not sufficient - social interactions must occur on a faster timescale compared to individual assessment, and the difference in perceived environmental impact must be small. This simple model suggests a scenario to achieve large reductions in environmental impact, which involves incrementally more active and potentially more costly behavior being consistently adopted under increasing social pressure for proenvironmentalism.

ecology↗

bioRxiv2021

Viral transduction and the dynamics of bacterial adaptation

Transduction - horizontal gene transfer (HGT) by viruses - is an important macroevolutionary force in prokaryotes, contributing to functional innovation and lineage diversification. In contrast, the role that transduction plays in bacterial microevolutionary adaptation is poorly known. By facilitating the transfer of beneficial alleles between host cells, transduction may accelerate adaptation. But transduction also carries the risk of transferring deleterious alleles, which, in addition to the demographic cost of viral infection, may hinder adaptation. Here we resolve the conflicting effects of transduction on bacterial adaptation in a simple eco-evolutionary model for large populations characterized by a quantitative (resource-use) trait with a single evolutionary optimum. Our model focuses on generalized transduction by virulent phages. Away from the optimum, the effect of transferring beneficial alleles dominates and transduction tends to accelerate adaptation. Close to the optimum, transduction generates a large amount of stochasticity in the population adaptive trajectory, thus hindering adaptation. Under disruptive selection, transduction may either limit (as sexual recombination would) or promote phenotypic diversification, or drive transient optimization whereby phenotypic subpopulations recurrently visit the optimum. Our modeling framework paves the way to study complex adaptive feedbacks between bacterial hosts and phages generated by the combination of deterministic and stochastic effects of transduction.

evolutionary biology↗

bioRxiv2019

Microbial evolution reshapes soil carbon feedbacks to climate change

Microbial decomposition of soil organic matter is a key component of the global carbon cycle. As Earths climate changes, the response of microbes and microbial enzymes to rising temperatures will largely determine the soil carbon feedback to atmospheric CO2. However, while increasing attention focuses on physiological and ecological mechanisms of microbial responses, the role of evolutionary adaptation has been little studied. To address this gap, we developed an ecosystem-evolutionary model of a soil microbe-enzyme system under warming. Constraining the model with observations from five contrasting sites reveals evolutionary aggravation of soil carbon loss to be the most likely outcome; however, temperature-dependent increases in mortality could cause an evolutionary buffering effect instead. We generally predict a strong latitudinal pattern, from small evolutionary effects at low latitude to large evolutionary effects at high latitudes. Accounting for evolutionary mechanisms will likely be critical for improving projections of Earth system responses to climate change.

ecology↗