Search results for " evolution."

Artificial selection of microbial communities: the effect of diversity and the role of interspecific interactions

2021

In agriculture, the plants and animals that are bred come from long-term artificial selection procedures that aim at producing individuals with desirable traits. Such procedures can be applied at levels of biological organization higher than the individual such as the community level, which is of particular interest in the field of microbial community engineering. Indeed, microbial communities play key roles in agriculture but also in the environment, health and industry, and a growing body of literature shows promising results regarding the artificial selection of microbial communities for desirable functions. However, for artificial selection procedures at the community level to be effici…

Alcohol Abuse Mediates the Association between Baseline T/C Ratio and Anger Expression in Intimate Partner Violence Perpetrators.

2015

The imbalance between testosterone (T) and cortisol (C) levels has been proposed as a possible marker of risk for intimate partner violence (IPV). Moreover, it could be related to a high probability of adopting risky behaviors such as alcohol abuse which, in turn, promotes the onset of IPV. This study tested the potential mediating effect of alcohol consumption on the relationship between baseline T/C ratio and anger expression in IPV perpetrators and non-violent controls. Alcohol consumption was higher in the former than controls. A high baseline T/C ratio was only associated with high anger expression in IPV perpetrators, and this association was mediated by high alcohol consumption. Thus…

Genomic divergence landscape in recurrently hybridizing Chironomus sister taxa suggests stable steady state between mutual gene flow and isolation

2021

Abstract Divergence is mostly viewed as a progressive process often initiated by selection targeting individual loci, ultimately resulting in ever increasing genomic isolation due to linkage. However, recent studies show that this process may stall at intermediate stable equilibrium states without achieving complete genomic isolation. We tested the extent of genomic isolation between two recurrently hybridizing nonbiting midge sister taxa, Chironomus riparius and Chironomus piger, by analyzing the divergence landscape. Using a principal component‐based method, we estimated that only about 28.44% of the genomes were mutually isolated, whereas the rest was still exchanged. The divergence land…

A Bayesian stable isotope mixing model for coping with multiple isotopes, multiple trophic steps and small sample sizes

2022

We introduce a Bayesian stable isotope mixing model for estimating the relative contributions of different dietary components to the tissues of consumers within food webs. The model is implemented with the probabilistic programming language Stan. The model incorporates isotopes of multiple elements (e.g. C, N, H) for two trophic levels, when the structure of the food web is known. In addition, the model allows inclusion of latent trophic levels (i.e. for which no empirical data are available) intermediate between sources and measured consumers. Running the model in simulations driven by a real dataset from Finnish lakes, we tested the sensitivity of the posterior distributions by altering c…

Comparison of muscle and hair stable isotope ratios in three phocid seals

2020

The transformation of the Horatian Sabine farm in Persius? Satire 6

2020

The purpose of this article is to focus on the motif of the countryside in Roman satire. In particular, it aspires to study the way the Sabine farm is delineated in Horace's Satire 2.6 and later in his Epistles, in order to elucidate the evolution of this motif in Persius? 6th Satire. In this poem, Persius addresses Caesius Bassus, who retreats to Sabine to seek poetic inspiration, but seems trapped in the paths of earlier poetry and cannot attain bliss, while the poet achieves it in the port of Luna.

Camouflage in arid environments: the case of Sahara-Sahel desert rodents

2020

Deserts and semi-deserts, such as the Sahara-Sahel region in North Africa, are exposed environments with restricted vegetation coverage. Due to limited physical surface structures, these open areas provide a promising ecosystem to understand selection for crypsis. Here, we review knowledge on camouflage adaptation in the Sahara-Sahel rodent community, which represents one of the best documented cases of phenotype-environment convergence comprising a marked taxonomic diversity. Through their evolutionary history, several rodent species from the Sahara-Sahel have repeatedly evolved an accurate background matching against visually-guided predators. Top-down selection by predators is therefore …

Interpretation of gut microbiota data in the ‘eye of the beholder’: A commentary and re‐evaluation of data from ‘Impacts of radiation exposure on the…

2021

1.Evidence that exposure to environmental pollutants can alter the gut microbiota composition of wildlife includes studies of rodents exposed to radionuclides. 2.Antwis et al. (2021) used amplicon sequencing to characterise the gut microbiota of four species of rodent (Myodes glareolus, Apodemus agrarius, A. flavicollis and A. sylvaticus) inhabiting the Chernobyl Exclusion Zone (CEZ) to examine possible changes in gut bacteria (microbiota) and gut fungi (mycobiota) associated with exposure to radionuclides and whether the sample type (from caecum or faeces) affected the analysis. 3.The conclusions derived from the analyses of gut mycobiota are based on data that represent a mixture of inges…

Return of the Apex Predator : How Brown Trout (Salmo trutta) Re-Establishment Shapes an Ecosystem

2021

Re-establishment of a declined apex predator fish species in a lake ecosystem may have dramatic effects on other fish and plankton community already inhabiting the ecosystem. We studied mechanistically potential impacts of re-establishment of the brown trout (Salmo trutta) in the west-central European Lake Constance focusing on two commercially important fish species: whitefish and Eurasian perch. We compared simulation model outputs from two versions of an allometric trophic network model for Lake Constance, one with and one without the trout as the apex predator. The re-establishment of the declined brown trout reduced the perch population directly by predation and indirectly by increased…

Environmental context determines pollution impacts on ecosystem functioning

2023

Global change assessments have typically ignored synthetic chemical pollution, despite the rapid increase of pharmaceuticals, pesticides and industrial chemicals in the environment. Part of the problem reflects the multifarious origins of these micropollutants, which can derive from urban and agricultural sources. Understanding how micropollutants harm ecosystems is a major scientific challenge due to asymmetries of stress across trophic levels and ecological surprises generated by multiple drivers interacting in human-impacted landscapes. We used field assays above and below municipal wastewater treatment plants (WWTPs) in 60 sampling locations across 20 Swiss streams to test how micropoll…