Biology subjects

Wynn, J.

Publications and source records attributed to Wynn, J..

9 recordsLinked to original sources

bioRxiv2026

Rapid and divergent changes in the continental-scale organisation of a short-lived songbird's migratory strategy

It is hard to predict how rapidly songbird migration will change in the Anthropocene. Indeed, since songbird migration is thought to have a strong heritable component, the continental-scale organisation of migratory movement might be seen as fairly inflexible. Perhaps one of the best models for the ecology and evolution of migration is the Eurasian blackcap (Sylvia atricapilla) which, as part of a continent-wide effort to characterise blackcap migratory phenotype, we geolocator-tracked from breeding sites in eastern Poland. Rather than migrating in the expected south-easterly migratory direction, these birds migrated south and south-west - suggesting that blackcaps in the east of their range have switched migratory direction. We sought to investigate the extent of this phenomenon using almost a century of ringing data, which confirmed that blackcaps breeding across the entirety of Eastern Europe have indeed almost completely stopped using their historic eastern flyway. Instead, a shorter-distance west-migrating phenotype has emerged, which we find is consistent with warmer winter temperatures opening up wintering sites at more northerly latitudes in the west. We discuss what drives changes in migratory behaviour over short timescales; and consider what this tells us about how migratory information is inherited.

animal behavior and cognition↗

bioRxiv2026

The road to nowhere: geolocation-by-genotype traces large-scale yellow-browed warbler vagrancy to central Siberia

Vagrant animals - individuals found far outside their normal range - offer powerful natural experiments for understanding migratory mechanisms. The yellow-browed warbler (Phylloscopus inornatus) provides perhaps the best-yet example, typically migrating from Siberia to South/Southeast Asia yet found in increasingly large numbers in Western Europe. This represents a strikingly unresolved evolutionary puzzle: why do so many migrants consistently move in almost the complete wrong direction? A critical first step toward solving this enigma is determining where these birds come from. If vagrants came from the proximal western range edge this would imply simple disorientation, whilst a more easterly origin could imply large-scale reverse misorientation. Here, we develop a geolocation-by-genotype algorithm for low-coverage whole-genome resequencing data collected from feathers. Our method identifies spatially informative SNPs; clusters them to account for covariance in allele frequency through space; and employs a bootstrapped maximum-likelihood framework to estimate spatial origin with uncertainty. Applied to more than 80 European-caught birds, our results place their origin in central Siberia (118{degrees}E; 89-134{degrees}E [95% CI]); over 2000km east of the western range edge. These results suggest mass misorientation in a near-reverse direction, and highlight the yellow-browed warbler as an exceptional system for probing the mechanism, ontogeny and evolution of migration.

animal behavior and cognition↗

bioRxiv2026

Magnetic compass orientation behaviour of Eurasian blackcaps at the predicted 110-120 MHz upper cut-off frequency for radiofrequency-field effects

Night-migratory songbirds use the Earths magnetic field to guide their migratory journeys. Most evidence suggests that the magnetic compass sensor is a flavin-tryptophan radical pair whose operation is disrupted by broadband radiofrequency (RF) fields at frequencies up to [~]116 MHz. Here, we test whether broadband 110-120 MHz RF fields affect the magnetic orientation behaviour of night-migratory Eurasian blackcaps (Sylvia atricapilla). We found that the birds oriented in their expected migratory direction in the natural geomagnetic field (NMF) control condition and that they turned their orientation [~]120{degrees} when the field was rotated 120{degrees} horizontally (changed magnetic field, CMF). When they were exposed to broadband 110-120 MHz RF fields, the birds continued to orient in the appropriate direction in the NMF. In the CMF, we found orientation behaviour that was not consistent with the expected direction. We conclude that the birds could still orient when exposed to 110-120 MHz fields, but speculate that their magnetic orientation capabilities might have been somewhat reduced compared to the control condition. We suggest that 110-120 MHz could represent a grey zone of reduced magnetic orientation capability centred at the cut-off frequency predicted for a flavin-based radical pair (probably in the flavoprotein cryptochrome).

animal behavior and cognition↗

bioRxiv2023

The unexpected consequences of predictor error in ecological model selection

1O_LIThe ability to select statistical models based on how well they fit an empirical dataset is a central tenet of modern bioscience. How well this works, though, depends on how goodness-of-fit is measured. Likelihood and its derivatives (e.g. AIC) are popular and powerful tools when measuring goodness-of-fit, though inherently make assumptions about the data. One such assumption is absence of error on the x-axis (i.e. no error in the predictor). This, however, is often not correct and deviations from this assumption are often hard (or impossible) to measure. C_LIO_LIHere, we show that, when predictor error is present, goodness-of-fit as perceived using likelihood will increase with decreases in sample size, effect size, predictor error and predictor variance. This results in predictors with increased effect size, predictor variance or predictor error being punished. As a consequence, we suggest that larger effect sizes are biased against in likelihood-based model comparison. Of note: (i) this problem is exacerbated in datasets with larger samples sizes and a broader range of predictor values - typically considered desirable biological data collection; and (ii) the magnitude of this effect is non-trivial given that proxy error (caused by using correlates of a predictor rather than the predictor itself) can lead to unexpectedly high amounts of error. C_LIO_LIWe investigate the effects of our findings in an empirical dataset of wood anemone (Anemone nemorosa) first flowering date regressed against temperature. Our results show that the proxy error caused by using air temperature rather than ground temperature results in a {triangleup}AIC of around 3. We also demonstrate potential consequences for model selection procedures with autocorrelation (e.g. sliding window approaches). Via simulation we show that in the presence of predictor error AIC will favour autocorrelated, lower effect size predictors (such as those found on the edges of predictive windows), rather than the a priori specified true window. C_LIO_LIOur results suggest significant and far-reaching implications for biological inference with model selection for much of todays ecology using observational data under non-experimental conditions. We assert that no obvious, globally-applicable solution to this problem exists; and propose that quantifying predictor error is key in accurate ecological model selection going forward. C_LI

ecology↗

bioRxiv2023

Multi-modal breath measurements for biomarker discovery

Breath contains numerous classes of compounds and biomolecules that could potentially be used as biomarkers for infectious disease as well as a range of other respiratory conditions or states. A testbed for simultaneous, multi-modal measurements was developed. Seventeen healthy subjects provided breath samples at baseline repiratory rate for particle size, lipid composition and bacterial nucleic acid composition analysis. The majority of the particles the participants exhaled at baseline were smaller than 5 m, consistent with previous literature. The exhaled breath particulate contained lipids found in lung surfactant, indicating origin in the lung. Although bacterial DNA was not significantly higher in the exhaled breath particulate than in the environmental background, the metagenome of the breath was distinct from the environment, oral cavity and nasal passages of the participants. The low abundance of the breath microbiome limited analysis. The multi-modal breath testbed has promise for discovery of breath biomarkers and as a reference for biomarkers of different classes that are currently being used.

genomics↗

bioRxiv2022

bi-axial orientation could explain range expansion in a migratory songbird

The likelihood of a new migratory route evolving is a function of the associated fitness payoff, and the probability that the route arises in the first place. Cross-breeding studies suggest that young birds migrate in a direction intermediate between their parents, though this would seemingly not explain how highly divergent migratory trajectories arise in apparently sympatric populations. It has been suggested that diametrically opposed reverse migratory trajectories might be surprisingly common, and if such routes were heritable it follows that they could underlie the rapid evolution of divergent migratory trajectories. Here, we used Eurasian blackcap (Sylvia atricapilla; blackcap) ringing recoveries and geolocator trajectories to investigate whether a recently-evolved northwards autumn migratory route could be explained by the reversal of each individuals expected southwards migratory direction. We found that northwards migrants were recovered closer to the sites specified by a precise axis reversal than would be expected by chance, consistent with the rapid evolution of new migratory routes via bi-axial variation in orientation. We suggest that the surprisingly high probability of axis reversal might allow birds to expand their wintering ranges rapidly, and hence propose that understanding how direction is encoded is crucial when characterising the genetic basis of migratory direction and how this relates to route evolution.

zoology↗

bioRxiv2022

Optimization of dynamic soaring in a flap-gliding seabird and its impacts on large-scale distribution at sea

Dynamic soaring harvests energy from a spatiotemporal wind gradient, allowing albatrosses to glide over vast distances. However, its use is challenging to demonstrate empirically, and has yet to be confirmed in other seabirds. Here we investigate how flap-gliding Manx Shearwaters optimise their flight for dynamic soaring. We do so by deriving a new metric, the horizontal wind effectiveness, that quantifies how effectively flight harvests energy from a shear layer. We evaluate this metric empirically for fine-scale trajectories reconstructed from bird-borne video data using a simplified flight dynamics model. We find that the birds undulations are phased with their horizontal turning to optimise energy harvesting. We also assess the opportunity for energy harvesting in long-range, GPS-logged foraging trajectories, and find that Manx Shearwaters optimise their flight to increase the opportunity for dynamic soaring during favourable wind conditions. Our results show how small-scale dynamic soaring impacts large-scale Manx Shearwater distribution at sea. TeaserFlap-gliding shearwaters harvest wind energy by fine-scale trajectory optimization and this impacts their large-scale distribution at sea.

animal behavior and cognition↗

bioRxiv2020

Deep whole genome sequencing of multiple proband tissues and parental blood reveals the complex genetic etiology of congenital diaphragmatic hernias

The diaphragm is a mammalian muscle critical for respiration and separation of the thoracic and abdominal cavities. Defects in the development of the diaphragm are the cause of congenital diaphragmatic hernia (CDH), a common birth defect. In CDH, weaknesses in the developing diaphragm allow abdominal contents to herniate into the thoracic cavity and impair lung development, leading to a high neonatal mortality. The genetic etiology of CDH is complex. Single nucleotide variants (SNVs), insertion/deletions (indels), and structural/copy number variants in more than 150 genes have been associated with CDH, although few genes are recurrently mutated in multiple patients and recurrently mutated genes can be incompletely penetrant. This suggests that multiple genetic variants in combination, other not yet investigated classes of variants, and/or nongenetic factors contribute to CDH susceptibility. However, to date no studies have comprehensively investigated the contribution of all possible classes of variants throughout the genome to the etiology of CDH. In our study, we used a unique cohort of four patients with isolated CDH with samples from blood, skin, and diaphragm connective tissue and parental blood samples and deep whole genome sequencing to assess germline and somatic de novo and inherited variants of various sizes (SNVs, indels, and structural variants) in exons, introns, UTRs, and intergenic regions. In each patient we found a different mutational landscape that included germline de novo, and inherited SNVs and indels in multiple genes. We also found in two patients an inherited 343 bp deletion interrupting an annotated enhancer of the CDH associated gene, GATA4, and we hypothesize that this common deletion (found in 1-2% of the population) acts as a sensitizing allele for CDH. Overall, our comprehensive reconstruction of the genetic architecture of four CDH individuals demonstrates that the etiology of CDH is heterogeneous and multifactorial. AUTHOR SUMMARYDeep whole genome sequencing of family trios shows that etiology of congenital diaphragmatic hernias is heterogeneous and multifactorial.

genetics↗

bioRxiv2017

Genetic analysis of de novo variants reveals sex differences in complex and isolated congenital diaphragmatic hernia and indicates MYRF as a candidate gene

Congenital diaphragmatic hernia (CDH) is one of the most common and lethal birth defects. Previous studies using exome sequencing support a significant contribution of coding de novo variants in complex CDH cases with additional anomalies and likely gene-disrupting (LGD) variants in isolated CDH cases. To further investigate the genetic architecture of CDH, we performed exome or genome sequencing in 283 proband-parent trios. Combined with data from previous studies, we analyzed a total of 357 trios, including 148 complex and 209 isolated cases. Complex and isolated cases both have a significant burden of deleterious de novo coding variants (1.7~fold, p= 1.2x10-5 for complex, 1.5~fold, p= 9.0x10-5 for isolated). Strikingly, in isolated CDH, almost all of the burden is carried by female cases (2.1~fold, p=0.004 for likely gene disrupting and 1.8~fold, p= 0.0008 for damaging missense variants); whereas in complex CDH, the burden is similar in females and males. Additionally, de novo LGD variants in complex cases are mostly enriched in genes highly expressed in developing diaphragm, but distributed in genes with a broad range of expression levels in isolated cases. Finally, we identified a new candidate risk gene MYRF (4 de novo variants, p-value=2x10-10), a transcription factor intolerant of mutations. Patients with MYRF mutations have additional anomalies including congenital heart disease and genitourinary defects, likely representing a novel syndrome.

genomics↗