Biology subjects

Ries, L.

Publications and source records attributed to Ries, L..

8 recordsLinked to original sources

bioRxiv2026

Large-scale atmospheric circulation cells regulate migratory dynamics of the iconic monarch butterfly

Understanding the impacts of climate on migratory dynamics is a priority for global change research, especially as phenological mismatches have been identified as a primary concern for long-distance migration. The eastern monarch (Danaus plexippus) is a flagship species for insect migration, but there has been surprisingly little research on their spring and summer migratory timing and mismatches with their key breeding resources. We show that spring, but not summer, phenological mismatch with their milkweed host plants has the potential to be a limiting factor in the eastern monarchs yearly population growth. To better understand arrival at their breeding grounds, we developed models specifically to tease apart the factors that push (from departure grounds), pull (towards arrival grounds), or facilitate flow (in the flight corridor) during migration. We found wind (flow) dynamics to be the most important factor associated with arrival timing, especially in spring. Further, we show how spring and summer migratory flyways coincide with the large-scale Hadley and Ferrel atmospheric cells respectively, and how their dynamics appear to be essential for understanding monarch migratory timing.

ecology↗

bioRxiv2025

Different transcriptional responses to developmental versus short-term acclimation temperatures in Pieris rapae

To anticipate the role of thermal plasticity in evolutionary responses to climate change, it is critical to identify the molecular processes which underlie responses to temperature across different timescales. However, existing transcriptomic studies largely focus on responses to acute thermal stress or do not manipulate temperature across multiple timescales. We used RNA-sequencing to measure gene expression of Pieris rapae larvae exposed to a full factorial combination of non-stressful high and low temperatures across a long-term developmental timescale and a short-term acclimation timescale. This study design allowed us to separate genes associated with developmental thermal plasticity versus short-term acclimation responses, respectively. We observed that few genes were differentially expressed in response to both developmental temperature and short-term acclimation temperature, though there were some functional similarities across the two gene sets. This result suggests that the expression of different genes underlies thermal plasticity acting on different timescales, and thus these responses may evolve independently. Genes responsive to developmental temperature include those related to hormone activity and cold acclimation, while short-term acclimation temperature affected the expression of several cuticle protein genes. Both developmental and short-term acclimation temperature treatments affected the expression of genes involved in detoxification and protein folding. Finally, we identified a small subset of genes for which expression levels were dependent on the interaction between developmental and short-term acclimation temperature treatments, providing possible mechanisms by which developmental temperature may affect an organisms capacity for acclimation responses later in life.

ecology↗

bioRxiv2024

Deep computer vision reveals the mediation of thermal-melanism and body size by precipitation and sex in a threatened alpine butterfly, Parnassius smintheus

Insect morphologies are strongly tied to selective forces, yet due to variation in these forces and finite resources, insects must strategically invest in select morphologies while deprioritizing others. Melanism and body size may be one such potential trade-off that insects navigate and these two factors are important for fecundity, dispersal, thermoregulation, anti-desiccation, and immunity. In this work, we examined how sex and environmental factors mediate a potential body-size/melanism trade-off in the cold-adapted butterfly Parnassius smintheus (Lepidoptera: Papilionidae). We used deep computer vision approaches and museum specimen photography to process over 1,000 images of the species. We found that body-size and melanism are strongly mediated by temperature and elevation (thermal-melanism hypothesis) and that precipitation mediates these slopes for males and females differently. Notably, under the wettest conditions, females exhibit stronger concordance with the thermal-melanism hypothesis while the relationship for males is inverted, suggesting increased competition among males in cold-wet environments. Our results highlight the importance of considering sex when examining how the environment influences intraspecific morphological variation, especially under projected scenarios of global climate change.

ecology↗

bioRxiv2023

Rising minimum temperatures contribute to 50 years of shifting Arctic and boreal butterfly communities in North America

AbstractGlobal climate change has been identified as a major driver of observed insect declines, yet in many regions there are critical knowledge gaps for how communities are responding to climate. Poleward regions are of particular interest because warming is most rapid while biodiversity data are most sparse. Building on recent advances in occupancy modeling of presence-only data, we reconstructed 50 years (1970-2019) of butterfly population trends in response to rising minimum temperatures in one of the most under sampled regions of the continent. Among 90 modeled species, we found that cold-adapted species are far more often in decline compared to their warm-adapted, more southerly distributed counterparts. Further, in a post-hoc analysis using species traits, we find that species range-wide average annual temperature and wingspan are a consistent predictor of occupancy changes. Species with warmer ranges and larger wingspans were most likely to be increasing in occupancy. Our results provide the first look at macroscale butterfly biodiversity shifts in a critically under sampled region of North America. Further, these results highlight the potential of leveraging the wealth of presence only data, the most abundant source of historical insect biodiversity. New approaches to the modeling of presence only data will match recent increases in community science participation with sparse historical records to reconstruct trends even in poorly sampled regions.

ecology↗

bioRxiv2022

Adoption of modern pest control systems associated with declines in butterfly abundance across Midwestern monitoring network

Mounting evidence shows overall insect abundances are in decline globally. Habitat loss, climate change, and pesticides have all been implicated, but their relative effects have never been evaluated in a comprehensive large-scale study. We harmonized 17 years of land use, climate, multiple classes of pesticides, and butterfly survey data across 81 counties in five states in the US Midwest. We find community-wide declines in total butterfly abundance and species richness to be most strongly associated with pesticides in general, and for butterflies species richness the use of neonicotinoid-treated seeds in particular. This included the abundance of the migratory monarch (Danaus plexippus), whose decline is the focus of intensive debate and public concern. Insect declines cannot be understood without comprehensive data on all putative drivers, and the 2015 cessation of neonicotinoid data releases in the US will impede future research. One Sentence SummaryShifts in insecticide use towards neonicotinoid-treated seeds are associated with an 8 percent decline in butterfly species diversity across the American Corn Belt.

ecology↗

bioRxiv2020

Functional characterization of clinical isolates of the opportunistic fungal pathogen Aspergillus nidulans

Aspergillus nidulans is an opportunistic fungal pathogen in patients with immunodeficiency and virulence of A. nidulans isolates has mainly been studied in the context of the chronic granulomatous disease (CGD), with characterization of clinical isolates obtained from non-CGD patients remaining elusive. This study therefore carried out a detailed biological characterization of two A. nidulans clinical isolates (CIs), obtained from a patient with breast carcinoma and pneumonia and from a patient with cystic fibrosis that underwent lung transplantation, and compared them to the reference, non-clinical A4 strain. Both CIs presented increased growth in comparison to the reference strain in the presence of physiologically-relevant carbon sources. Metabolomic analyses showed that the three strains are metabolically very different from each other in these carbon sources. Furthermore, the CIs were highly susceptible to cell wall perturbing agents but not to other physiologically-relevant stresses. Genome analyses identified several frame-shift variants in genes encoding cell wall integrity (CWI) signalling components. Significant differences in CWI signalling were confirmed by western blotting among the three strains. In vivo virulence studies using several different models revealed that strain MO80069 had significantly higher virulence in hosts with impaired neutrophil function when compared to the other strains. In summary, this study presents detailed biological characterization of two A. nidulans sensu stricto clinical isolates. Just like in A. fumigatus, strain heterogeneity exists in A. nidulans clinical strains that can define virulence traits. Further studies are required to fully characterize A. nidulans strain-specific virulence traits and pathogenicity. ImportanceImmunocompromised patients are susceptible to infections with opportunistic filamentous fungi from the genus Aspergillus. Although A. fumigatus is the main etiological agent of Aspergillus spp.-related infections, other species, such as A. nidulans are prevalent in a condition-specific manner. A. nidulans is a predominant infective agent in patients suffering from chronic granulomatous disease (CGD). A. nidulans isolates have mainly been studied in the context of CGD, although infection with A. nidulans also occurs in non-CGD patients. This study carried out a detailed biological characterization of two non-CGD A. nidulans clinical isolates and compared it to a reference strain. Phenotypic, metabolomic and genomic analyses highlight fundamental differences in carbon source utilization, stress responses and maintenance of cell wall integrity among the strains. One clinical strain had increased virulence in models with impaired neutrophil function. Just as in A. fumigatus, strain heterogeneity exists in A. nidulans clinical strains that can define virulence traits.

microbiology↗

bioRxiv2019

Butterfly abundance declines over 20 years of systematic monitoring in Ohio, USA

Severe insect declines make headlines, but they are rarely based on systematic monitoring outside of Europe. We estimate the rate of change in total butterfly abundance and the population trends for 81 species using 21 years of systematic monitoring in Ohio, USA. Total abundance is declining at 2% per year, resulting in a cumulative 33% reduction in butterfly abundance. Three times as many species have negative population trends compared to positive trends. The rate of total decline and the proportion of species in decline mirror those documented in three comparable long-term European monitoring programs. Multiple environmental changes such as climate change, habitat degradation, and agricultural practices may contribute to these declines in Ohio and shift the makeup of the butterfly community by benefiting some species over others. Our analysis of life-history traits associated with population trends shows an impact of climate change, as species with northern distributions and fewer annual generations declined more rapidly. However, even common and invasive species associated with human-dominated landscapes are declining, suggesting widespread environmental causes for these trends. Declines in common species, although they may not be close to extinction, will have an outsized impact on the ecosystem services provided by insects. These results from the most extensive, systematic insect monitoring program in North America demonstrate an ongoing defaunation in butterflies that on an annual scale might be imperceptible, but cumulatively has reduced butterfly numbers by a third over 20 years.

ecology↗

bioRxiv2019

Tracking trends in monarch abundances over the 20th century is currently impossible using museum records: a response to Boyle et al. (2019)

The onslaught of opportunistic data offers new opportunities to examine biodiversity patterns at large scales. However, the techniques for tracking abundance trends with such data are new and require careful consideration to ensure that variations in sampling effort do not lead to biased estimates. The analysis by Boyle et al. (2019) showing a mid-century increase in monarch abundance followed by a decrease starting in the 1960s used an inappropriate correction with respect to three dimensions of sampling effort: taxonomy, place, and time. When the data presentenced by Boyle et al. (2019) are corrected to account for biases in the collection process, the results of their analyses do not hold. The paucity of data that remain after accounting for spatial and temporal biases suggests that analyses of monarch trends back to the beginning of the 20th are currently not possible. Continued digitization of museum records is needed to provide a firm data basis to estimate population trends.

ecology↗