The pattern (space versus time) and scale (relative to the lifetime of individuals) of environmental variation is thought to play a central role in governing the evolution of the ecological niche and the maintenance of genetic variance in fitness. To evaluate this idea, we serially propagated an initially genetically uniform population of the bacterium Pseudomonas fluorescens for a few hundred generations in environments that differed in both the pattern and scale at which two highly contrasted carbon substrates were experienced. We found that, contrary to expectations, populations often evolved into a single niche specialist adapted to the less-productive substrate in variable environments and that the genetic variance in fitness across different components of the environment was not generally higher in variable environments when compared with constant environments. We provide evidence to suggest that our results reflect a novel constraint on niche evolution imposed by the supply of beneficial mutations available to selection in variable environments.
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http://dx.doi.org/10.1098/rspb.2007.0936 | DOI Listing |
Environ Monit Assess
January 2025
School of Earth Sciences, East China University of Technology, Nanchang, 330013, China.
Investigating the effects of urbanization at the county level on the balance of the carbon budget is essential for progress toward achieving "dual carbon" objectives at the county scale. Based on land use and economic data, this study elucidates the spatiotemporal evolution of urbanization and carbon budget balance ratio in 84 counties in Jiangxi Province from 1980 to 2020. Optimal geographic detectors and geographically weighted random forests were used to explore the impact of urbanization on the carbon budget balance ratio.
View Article and Find Full Text PDFInt Arch Occup Environ Health
January 2025
Department of Physical Medicine and Rehabilitation, Lariboisière- Fernand Widal Hospital, Université Paris Cité, Assistance Publique- Hôpitaux de Paris, Paris, France.
Purpose: Little is known about the relationship between conflict at work and incident chronic low back pain (CLBP). Thus, this retrospective cohort study analyzed the association between conflict at work and the five-year incidence of CLBP in adults living in Germany.
Methods: This study included individuals aged 18-65 years reporting conflict at work for the first time in one of 1,293 general practices in Germany between 2005 and 2022 (index date).
Curr Opin Support Palliat Care
January 2025
Department of Medical Social Science, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.
Purpose Of The Review: Today, two-thirds of all cancer survivors are at least 65 years old. Older cancer survivors have complex care needs, and addressing their social determinants of health (SDoH) is critical for improving and managing survivorship outcomes for this uniquely vulnerable population, yet research specifically examining these associations remains limited and emergent. To this end, we describe the emergent body of evidence on the associations between SDoH domains and older cancer survivors' outcomes.
View Article and Find Full Text PDFJ Dev Biol
December 2024
Comparative Histolab Padova, 35100 Padova, Italy.
The present, brief review paper summarizes previous studies on a new interpretation of the presence and absence of regeneration in invertebrates and vertebrates. Broad regeneration is considered exclusive of aquatic or amphibious animals with larval stages and metamorphosis, where also a patterning process is activated for whole-body regeneration or for epimorphosis. In contrast, terrestrial invertebrates and vertebrates can only repair injury or the loss of body parts through a variable "recovery healing" of tissues, regengrow or scarring.
View Article and Find Full Text PDFJ Xenobiot
January 2025
Institute of Environment, Florida International University, Miami, FL 33199, USA.
Food is essential for human survival; however, food can be an important route of exposure to contaminants. This study investigated the presence and distribution of anthropogenic contaminants in food consumed by families with small children in South Florida, United States, evaluating seasonal and socio-economic variabilities in chemical composition. QuEChERS protocols, followed by non-targeted analysis (NTA) using an LC-Orbitrap HRMS system, were used for the comprehensive screening of organic contaminants.
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