Biology subjects

Weigel, B.

Publications and source records attributed to Weigel, B..

5 recordsLinked to original sources

bioRxiv2026

Habitat context alters the pace of climate-driven community warming across terrestrial and freshwater ecosystems

As global temperatures rise, ecological communities are increasingly dominated by warm-affiliated species, a process known as community warming or thermophilisation. Yet, why different taxa exhibit different rates of community warming remains unclear. Habitat composition and structure are likely drivers of this variation, as the ecological consequences of warming are filtered by local environmental conditions. Using over 40 years of monitoring data spanning terrestrial (birds, insects, plants) and freshwater (phytoplankton) communities, we show that habitat structure determines how strongly communities track warming. Forest cover systematically slows thermophilisation by reducing communities sensitivity to temperature change, whereas habitat heterogeneity has weak and variable effects that differ among ecosystems. Together, these results demonstrate that uneven thermophilisation arises from habitat-mediated differences in how communities respond to a shared climatic signal. Incorporating these effects is essential for improving predictions of biodiversity change under ongoing climate warming.

ecology↗

bioRxiv2025

Decoding Plasticity Regulators and Transition Trajectories in Glioblastoma with Single-cell Multiomics

Glioblastoma (GB) is one of the most lethal human cancers, marked by profound intratumoral heterogeneity and near-universal treatment resistance. Cellular plasticity, the capacity of cancer cells to transition between phenotypic states, drives GB progression and resistance. However, the regulatory logic that permits or restricts specific state transitions remains poorly understood. Here, we integrated single-nucleus RNA and chromatin accessibility multi-ome profiles from over one million cells across primary IDH-wildtype GBs and developed scDORI, a scalable deep-learning framework to infer enhancer-driven gene regulatory networks (eGRNs) at single-cell resolution. Our analysis revealed a structured hierarchy of GB cell states governed by distinct regulatory programs, with marked variability in epigenetic plasticity that enables or constrains transitions. Neuronal-like tumor cells emerge as a low plasticity state that deploys active repression, in contrast to more permissive progenitor-like and astrocytic states. We identified the neuronal-like state-specific repressor MYT1L as a key regulator that silences master transcription factors of alternative states. MYT1L gain-of-function in patient-derived GB cells reduced chromatin accessibility, induced neuronal-like identity, and restricted proliferation and invasion in vivo, whereas loss-of-function reactivated plasticity and accelerated malignant features. Our findings delineate the epigenetic architecture and associated transcriptional master regulators that shape GB state trajectories, and establish safeguard repressors such as MYT1L as potential therapeutic targets to constrain malignant plasticity.

cancer biology↗

bioRxiv2023

Assessing the overlap between fishing activities and chondrichthyans distribution exposes high-risk areas for bycatch of threatened species

Sharks, rays, and chimaeras (chondrichthyans) play a crucial role in marine ecosystem functioning but are highly vulnerable to fishing. Hence, understanding the spatial overlap between chondrichthyans and fishing effort is essential for effective conservation and management. Here, we propose an integrated approach that combines Vessel Monitoring System data with geostatistical species distribution models to assess the potential impact of fishing on chondrichthyan populations in the western Adriatic Sea. By mapping the overlap between model-based chondrichthyan distribution, species richness, and the proportion of threathened species with bottom trawl fishing activities, we identify areas at high risk for chondrichthyan bycatch. Our findings show that many of these species are at risk across a large part of their distribution within the study area. Notably, there is a substantial spatial overlap between regions where threatened chondrichthyans are found and species-rich areas with locations of intensive bottom trawl fishing in the northern and central offshore regions of the western Adriatic, emphasizing the vulnerability of these species to fishing pressure. Furthermore, differences in overlap between distinct fishing gears highlight the importance of considering specific fishing practices when formulating management strategies. While our work provides novel insights to potential bycatch hotspots, limitations related to data sources, spatial resolution, and the inability to directly quantify fishing impacts should be considered. Nonetheless, our findings contribute to the development of targeted conservation and spatial management measures, offering a general approach to study model-based spatial hotspots aimed at protecting and sustaining chondrichthyan populations in the heavily exploited Adriatic Sea.

ecology↗

bioRxiv2022

Macrosystem community change in lake phytoplankton and its implications for diversity and function

The combined effects of eutrophication, land-use and climate change are major threats to aquatic ecosystems, their biodiversity and integrity in sustaining ecosystem functions. Disentangling the mechanisms by which environmental change contributes to community assembly processes and species niches remains challenging, especially at macro-ecological scales. Here, we collated phytoplankton community data including 853 lakes along a 1200km latitudinal gradient, monitored over four decades, to quantify the spatio-temporal and scale-dependent environmental impacts on species niches and assembly processes while accounting for species traits and phylogenetic constraints. Our results demonstrate the emergence of novel and widespread community composition clusters in previously more uniform communities. While total species richness remained relatively stable, changes in community weighted mean traits of the clusters indicate functional differences. A robust phylogenetic signal of species responses to the environment indicates strong niche conservatism and low taxonomic dispersion. Our findings imply profound spatio-temporal structuring of species co-occurrence patterns and highlight emerging functional differences of lake phytoplankton communities to environmental change over space and time.

ecology↗

bioRxiv2018

When is a fish stock collapsed?

Marine fish stock collapses are a major concern for scientists and society due to the potentially severe impacts on ecosystem resilience, food security and livelihoods. Yet the general state of harvested fish populations has proven difficult to summarize, and the actual occurrence rate of stock collapses remains unclear. We have carried out a literature review and multi-stock analysis to show that numerous definitions exist for classifying stocks as collapsed, and that the classification of a stocks status is sensitive to changes in the collapse definitions formulation. We suggest that the lack of a unified definition has contributed to contrasting perceptions on the state of fish stocks. Therefore, we comprehensively define what constitutes a fish stock collapse and provide a time-series based method for collapse detection. Unlike existing definitions, our definition is process-based, because it links together three important phases of collapse events: the abrupt decline, an ensuing period of prolonged depletion, and potential recovery. Furthermore, these phases are specified in terms of population turnover. Through systematic evaluation, our definition can accurately distinguish collapses from less severe depletions or natural fluctuations for stocks with diverse life histories, helping identify the stocks in greatest need of reparatory measures. Our study advocates the consistent use of definitions to limit both alarmist and conservative narratives on the state of fish stocks, and to promote cooperation between conservation and fisheries scientists. This will facilitate clear and accurate communication of science to both the public and to policy-makers to ensure healthy fish stocks in the future.

ecology↗