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We investigated the influence of age on survival and breeding rates in a long-lived species Rissa tridactyla using models with individual random effects permitting variation and covariation in fitness components among individuals. Differences in survival or breeding probabilities among individuals are substantial, and there was positive covariation between survival and breeding probability; birds that were more likely to survive were also more likely to breed, given that they survived. The pattern of age-related variation in these rates detected at the individual level differed from that observed at the population level. Our results provided confirmation of what has been suggested by other investigators: within-cohort phenotypic selection can mask senescence. Although this phenomenon has been extensively studied in humans and captive animals, conclusive evidence of the discrepancy between population-level and individual-level patterns of age-related variation in life-history traits is extremely rare in wild animal populations. Evolutionary studies of the influence of age on life-history traits should use approaches differentiating population level from the genuine influence of age: only the latter is relevant to theories of life-history evolution. The development of models permitting access to individual variation in fitness is a promising advance for the study of senescence and evolutionary processes.
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http://dx.doi.org/10.1086/324126 | DOI Listing |
JAACAP Open
September 2025
University of Vermont, Burlington, Vermont.
Objective: The transition to college is a period of growth and vulnerability for young adult health and well-being and provides a critical window for potential behavioral interventions. In this study, we sought to examine the trajectory of anxiety symptoms and their association with individual characteristics, exposure to stressors, and sleep behaviors during the transition to college.
Method: We recruited full-time, incoming undergraduate students at a university in the northeastern United States to participate during the first semester of college between October 21, 2022, and December 12, 2022.
Mar Life Sci Technol
August 2025
School of Ocean Sciences, China University of Geosciences (Beijing), Beijing, 100083 China.
Unlabelled: Marinisomatota (formerly recognized as Marinimicrobia, Marine Group A, and SAR406) are ubiquitous and abundant in marine environments, traditionally characterized as heterotrophic microorganisms. However, certain members of Marinisomatota have demonstrated the capacity to harness light for carbon dioxide fixation and the synthesis of organic compounds, thriving in the translucent zone or transitioning between the translucent and aphotic layers. The metabolic strategies driving the shift in trophic behaviors, and the factors influencing these transitions, remain largely unexplored.
View Article and Find Full Text PDFMicroPubl Biol
August 2025
Biological Sciences, Auburn University, Auburn, Alabama, United States.
Measures of organismal fitness must take into account reproductive output and survivorship across life-history stages. In , a laboratory model system, these traits are often quantified with egg-laying assays and egg-to-adult viability. While several protocols for automated egg counting exist, these methods typically preclude directly analyzing phenotypic distributions in resulting adults.
View Article and Find Full Text PDFJ Environ Manage
September 2025
Centre for Applied Water Science, University of Canberra, ACT, Australia; Department of Zoology, University of Otago, Dunedin, New Zealand.
One mechanism for improving the resilience of freshwater systems affected by climate change is to use environmental water to support refugial habitats which allow species, ecosystems and functions to persist and recover after severe droughts. We applied systematic conservation planning (SCP) to prioritise wetlands and lakes with the aim of informing the delivery of environmental water for the creation and protection of refugia habitat in the Murray-Darling Basin, Australia. SCP uses a complimentary algorithm to generate planning solutions that protect all target ecological assets for the lowest "cost" of the management constraints considered.
View Article and Find Full Text PDFMar Pollut Bull
September 2025
Florida International University, Civil and Environmental Engineering, 10555 West Flagler Street, Engineering Center, Miami, Florida 33174, USA. Electronic address:
Marine ecosystems are increasingly threatened by anthropogenic pollutants, including plastics, persistent organic pollutants, heavy metals, oil, and emerging contaminants. This meta-analysis examined the accumulation patterns of five major contaminants-mercury (Hg), polychlorinated biphenyls (PCBs), microplastics, per- and polyfluoroalkyl substances (PFAS), and polycyclic aromatic hydrocarbons (PAHs)-in relation to trophic level and lifespan across marine species. Data synthesis revealed distinct differences in bioaccumulation and biomagnification between legacy and emerging contaminants.
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