Biology subjects

Lancaster, L.

Publications and source records attributed to Lancaster, L..

5 recordsLinked to original sources

bioRxiv2026

Pest evolution amplifies projected crop losses under climate change

Climate change influences the physiology and population dynamics of ectothermic pests, with major repercussions for global crop production. Yet, how evolution modulates these outcomes remains unclear. We exposed the widespread beetle pest Callosobruchus maculatus to 10 years of experimental evolution at different temperatures and quantified thermal responses of life-history traits. Hot- and cold-adapted populations evolved differences in thermal sensitivity, but these were modest relative to evolved differences in trait averages. By leveraging high-resolution temperature time-series we show that the observed evolution translates into cold-adapted genotypes having highest fitness in cold climates and hot-adapted genotypes in warm climates. Hot-adapted beetles maximize fitness in warm climates by increased larval growth, resulting in larger body sizes and higher fecundity. This evolutionary strategy compounds projected crop losses under warming by increasing both intrinsic population growth and per-capita host consumption rates. By year 2100 under intermediate-to-high warming (SSP3-7.0), pest evolution is projected to increase global crop damage potential by +113% from present--twice that expected from warming alone (not accounting for evolution). In major crop-producing areas, where temperatures and the beetles host consumption rates are already high, warming increases average crop damage potential by +29%, but evolution amplifies this three-fold to +87%. Evolution also expands C. maculatus projected colonizable range and in some regions even flips forecasted crop damage reductions into increases. These results identify climate-driven evolution of pest life-histories as an amplifier of agricultural losses and suggest that current projections may significantly understate the threat warming poses to future food security.

ecology↗

bioRxiv2026

The flaws of fitness functions in changing environments

When predicting species responses to changing environments, one can use mathematical functions that describe how individual fitness components depend on the environment, or a single "composite" function that directly links fitness to the environmental state. The former approach is a cornerstone of process-based modelling, but the latter remains standard for developing fundamental theory and making ecological predictions. Yet, fitness is not a single instantaneous trait, but an integrated outcome of multiple underlying processes accruing throughout an organisms life. We show that by ignoring the distinct environmental dependence of the underlying processes, predictions from composite fitness functions become inherently flawed in variable environments. We explore the magnitude of this error by leveraging empirical thermal reaction norms for four important life-history processes in an insect pest, the seed beetle Callosobruchus maculatus. We parameterize two fitness functions: one explicitly modelling the temperature-dependence of the four life-history traits independently (the "ground truth") and one composite function, which treats fitness as a single, instantaneous outcome of the environment. By combining these two functions with hourly temperature data, we projected demographic responses under different warming scenarios across 300 sites over three beetle population origins (California, USA; Yemen; Brazil). We show that the composite function over- or underestimates fitness depending on subtle climatic differences and whether fitness is assumed to accumulate additively or multiplicatively, highlighting the problems of applying composite fitness functions to variable conditions. We conclude that explicitly modeling trait-specific processes will become increasingly important for accurate eco-evolutionary forecasting under future environmental change.

ecology↗

bioRxiv2024

Chromosome-scale genome assembly and linkage map for Silene uniflora reveal the recombination landscape in a rapidly evolving plant species

The genus Silene is an important model system for fields as diverse as sex chromosome evolution, speciation and disease ecology. However, genomic resources remain scarce in the genus. Here, we present a chromosome-scale genome assembly for S. uniflora, a hermaphroditic/gynodioecious species which is an important model for rapid adaptation to anthropogenic disturbance and the role of phenotypic plasticity in adaptive evolution. Using a combination of long-read and Hi-C sequencing technologies, we generated a 1,268 Mb genome assembly with a scaffold N50 of 40.72 Mb and 682 Mb assembled into 12 chromosomes. We annotated the genome using evidence from transcriptome and protein mapping in combination with ab initio gene prediction, resulting in 41,603 protein-coding genes and a BUSCO completeness score of 91%. We also present a linkage map which we used to validate the genome assembly and estimate local recombination rate across the genome. Comparison to the only two other Silene species with chromosome-scale genome assemblies reveals widespread genome rearrangements in the genus, suggesting Silene may be a promising study system for the role of genome rearrangement in evolution, particularly in the evolution of sex chromosomes and adaptation. Significance statementPlant species in the genus Silene (campions) are important study organisms in multiple areas of ecology and evolution. Sea campion (Silene uniflora) is an important model for investigations into rapid adaptation, phenotypic plasticity and parallel evolution. However, only two species have high-quality genome assemblies available, hampering studies of their genetics and evolution. We present a high-quality genome assembly, genetic map and gene annotation for sea campion. These will be important genomic resources for future studies of sea campion, other species in the genus Silene and the family Caryophyllaceae more generally.

evolutionary biology↗

bioRxiv2023

Low Gut Microbial Diversity Augments Estrogen-driven Pulmonary Fibrosis in Female-Predominant Interstitial Lung Disease

Although profibrotic cytokines such as IL-17A and TGF-{beta}1 have been implicated in interstitial lung disease (ILD) pathogenesis, interactions between gut dysbiosis, gonadotrophic hormones and molecular mediators of profibrotic cytokine expression, such as phosphorylation of STAT3, have not been defined. Here we show by chromatin immunoprecipitation sequencing (ChIP-seq) analysis of primary human CD4+ T cells that regions within the STAT3 locus are significantly enriched for binding by the transcription factor estrogen receptor alpha (ERa). Using the murine model of bleomycin-induced pulmonary fibrosis, we found significantly increased regulatory T cells compared to Th17 cells in the female lung. Genetic absence of ESR1 or ovariectomy in mice significantly increased pSTAT3 and IL-17A expression in pulmonary CD4+ T cells, which was reduced after repletion of female hormones. Remarkably, there was no significant reduction in lung fibrosis under either condition, suggesting that factors outside of ovarian hormones also contribute. Assessment of lung fibrosis among menstruating females in different rearing environments revealed that environments favoring gut dysbiosis augment fibrosis. Furthermore, hormone repletion following ovariectomy further augmented lung fibrosis, suggesting pathologic interactions between gonadal hormones and gut microbiota on lung fibrosis severity. Analysis in female sarcoidosis patients revealed a significant reduction in pSTAT3 and IL-17A levels and a concomitant increase in TGF-{beta}1 levels in CD4+ T cells, compared to male sarcoidosis patients. These studies reveal that estrogen is profibrotic in females and that gut dysbiosis in menstruating females augments lung fibrosis severity, supporting a critical interaction between gonadal hormones and gut flora in lung fibrosis pathogenesis.

immunology↗

bioRxiv2018

SOCIAL STRESS AS A PRIMING MECHANISM FOR THERMAL TOLERANCE DURING A POLEWARD RANGE SHIFT

Cold tolerance plays a critical role in determining species geographical range limits. Previous studies have found that range shifts in response to climate warming are facilitated by cold acclimation capacities, due to increasingly colder and variable weather at high latitudes, and that cold tolerance can also be influenced by social factors. In this study we combined experiments and field studies to investigate the climatic and social factors affecting cold tolerances in range-shifting populations of the female-polymorphic damselfly Ischnura elegans in northeast Scotland. In the field, we observed both environmental (measured via habitat suitability) and social (sex ratio and density) effects on cold tolerance (CTmin). Androchrome females (male-like females) were less susceptible to beneficial social effects on cold tolerance than gynochromes (female-like females), and correspondingly, gynochrome frequency increased at colder, environmentally-limiting sites towards the range margin. Our manipulations of density in the laboratory further provide novel, experimental evidence that social interactions directly impact cold tolerance n this species. These results suggest that reciprocal effects of social environments on thermal acclimation may be an important but commonly overlooked aspect of allee effects which contribute to the formation of range margins. Moreover, our results point to a wider need to consider the role of population and social dynamics to shape both the thermal physiology of individuals and the thermal niches of species.

evolutionary biology↗