The network architecture of streams and rivers constrains evolutionary, demographic and ecological processes of freshwater organisms. This consistent architecture also makes stream networks useful for testing general models of population genetic structure and the scaling of gene flow. We examined genetic structure and gene flow in the facultatively paedomorphic Idaho giant salamander, Dicamptodon aterrimus, in stream networks of Idaho and Montana, USA. We used microsatellite data to test population structure models by (i) examining hierarchical partitioning of genetic variation in stream networks; and (ii) testing for genetic isolation by distance along stream corridors vs. overland pathways. Replicated sampling of streams within catchments within three river basins revealed that hierarchical scale had strong effects on genetic structure and gene flow. amova identified significant structure at all hierarchical scales (among streams, among catchments, among basins), but divergence among catchments had the greatest structural influence. Isolation by distance was detected within catchments, and in-stream distance was a strong predictor of genetic divergence. Patterns of genetic divergence suggest that differentiation among streams within catchments was driven by limited migration, consistent with a stream hierarchy model of population structure. However, there was no evidence of migration among catchments within basins, or among basins, indicating that gene flow only counters the effects of genetic drift at smaller scales (within rather than among catchments). These results show the strong influence of stream networks on population structure and genetic divergence of a salamander, with contrasting effects at different hierarchical scales.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1365-294X.2010.04541.x | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Centre de Recherche sur la Biodiversité et l'Environnement, Université de Toulouse, Institut de Recherche pour le Développement, Institut National Polytechnique de Toulouse, Université Toulouse 3 - Paul Sabatier, Toulouse F-31062, France.
Unlike most rivers globally, nearly all lowland Amazonian rivers have unregulated flow, supporting seasonally flooded floodplain forests. Floodplain forests harbor a unique tree species assemblage adapted to flooding and specialized fauna, including fruit-eating fish that migrate seasonally into floodplains, favoring expansive floodplain areas. Frugivorous fish are forest-dependent fauna critical to forest regeneration via seed dispersal and support commercial and artisanal fisheries.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Electronics and Communication Engineering, Panimalar Engineering College, Chennai, India.
Sensors (Basel)
January 2025
Faculty of Applied Sciences, Macao Polytechnic University, Macao SAR 999078, China.
Visible-infrared person re-identification (VI-ReID) is a challenging cross-modality retrieval task to match a person across different spectral camera views. Most existing works focus on learning shared feature representations from the final embedding space of advanced networks to alleviate modality differences between visible and infrared images. However, exclusively relying on high-level semantic information from the network's final layers can restrict shared feature representations and overlook the benefits of low-level details.
View Article and Find Full Text PDFSci Total Environ
January 2025
Research Group of Physics and Technology of Advanced Materials, Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesa No. 10, Bandung, Jawa Barat 40132, Indonesia; Department of Physics, Faculty of Science, Institut Teknologi Sumatera, Jalan Terusan Ryacudu, Lampung Selatan, Lampung 35365, Indonesia. Electronic address:
Microplastic pollution has surfaced as a critical environmental concern, affecting ecosystems and human health globally. This study explored the application of several machine learning models, including the Tree algorithm, k-Nearest Neighbors (kNN), Random Forest (RF), Linear Regression (LR), Support Vector Machine (SVM), and Neural Networks (NN), to predict microplastic concentrations in the rivers of Indonesia's 24 provinces. By utilizing both environmental and anthropogenic data, the Tree algorithm exhibited the best performance, achieving a coefficient of determination (R) of 0.
View Article and Find Full Text PDFNat Rev Dis Primers
January 2025
European Reference Network for Rare Multisystemic Vascular Disease (VASCERN), HHT Rare Disease Working Group, Paris, France.
Hereditary haemorrhagic telangiectasia (HHT) is a vascular dysplasia inherited as an autosomal dominant trait and caused by loss-of-function pathogenic variants in genes encoding proteins of the BMP signalling pathway. Up to 90% of disease-causal variants are observed in ENG and ACVRL1, with SMAD4 and GDF2 less frequently responsible for HHT. In adults, the most frequent HHT manifestations relate to iron deficiency and anaemia owing to recurrent epistaxis (nosebleeds) or bleeding from gastrointestinal telangiectases.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!