Range Of Species Research Articles

Evolutionarily distinct lineages of a migratory bird of prey show divergent responses to climate change

Accurately predicting species’ responses to anthropogenic climate change is hampered by limited knowledge of their spatiotemporal ecological and evolutionary dynamics. We combine landscape genomics, demographic reconstructions, and species distribution models to assess the eco-evolutionary responses to past climate fluctuations and to future climate of an Afro-Palaearctic migratory raptor, the lesser kestrel (Falco naumanni). We uncover two evolutionarily and ecologically distinct lineages (European and Asian), whose demographic history, evolutionary divergence, and historical distribution range were profoundly shaped by past climatic fluctuations. Using future climate projections, we find that the Asian lineage is at higher risk of range contraction, increased migration distance, climate maladaptation, and consequently greater extinction risk than the European lineage. Our results emphasise the importance of providing historical context as a baseline for understanding species’ responses to contemporary climate change, and illustrate how incorporating intraspecific genetic variation improves the ecological realism of climate change vulnerability assessments.

Climate change impacts on altitudinal movements of society large mammals in the Alborz

This study examines the impact of climate change on the altitudinal movement patterns and number of individuals of four large mammal species within the Central Alborz Protected Area (CAPA) region of the Alborz Mountains, a biodiversity hotspot, over a 23-year period (1999 to 2022). During the warm season (May 25–September 29), temperatures were reported to have increased by 2–2.5 °C, while relative humidity was observed to have decreased by 4–4.5%. Compared to the past two decades (2000–2022), Caspian red deer were observed to initiate their annual high-altitude migrations 15–20 days earlier, with the number of individuals in the summer range increasing more than threefold. Wild goats also migrated earlier, with peak arrivals increasing from 20–36 (1999–2003) to 36–57 (2018–2022) between May 25 and May 31, highlighting temperature as the primary driver of herbivore movement. In contrast, brown bears exhibited more subtle altitudinal movement, likely influenced by both temperature and humidity. Wild boars, with an approximate 40% increase in the number of individuals, tended to return to lower elevations earlier than in previous years (1999–2003). These patterns highlight the role of climate as a significant regulator of movement ecology, influencing high-altitude habitat use. However, human-induced barriers, such as roads and settlements, present additional threats to these seasonal migrations. This underscores the urgent need for adaptive management strategies, including the protection of movement corridors, the expansion of core zones, and enhanced community engagement, to support the resilience of these species under changing climatic conditions.

Revealing hidden diversity and cryptic speciation in Antarctic marine gastropods (Heterobranchia: Cephalaspidea)

Abstract Recent studies have revealed significant hidden diversity and a high incidence of cryptic speciation in Antarctic marine gastropods. Originally, philinoid cephalaspideans in the Southern Ocean were classified within the genus Philine. However, molecular and morphological studies have shown that three genera encompass all known diversity instead. These are Antarctophiline, Waegelea and Spiraphiline, the first two belonging to the recently erected family Antarctophilinidae. In this study, 55 specimens were collected from the South Shetland Islands, across the South Atlantic Antarctic Ridge to Bouvet Island, and from the South Sandwich Islands and Bransfield Strait, between 134 and 4548 m depth. We conducted morpho-anatomical and phylogenetic analyses to describe two new Antarctophiline species: Antarctophiline abyssalis sp. nov. and Antarctophiline malaquiasi sp. nov. Molecular results support the validity of the two distinct species, consistent with observed morpho-anatomical differences in the digestive system (i.e. the shape of gizzard plates and salivary glands), shell shape and other external characters. Additionally, we evaluate the morphological affinities of the most common Antarctic species, Antarctophiline alata, throughout its distribution range. Overall biogeographical distributions are discussed in a systematic context. Our study is yet another example of how Antarctica keeps revealing itself as a cornerstone of gastropod diversity.

Designing Ambiguity Sets for Distributionally Robust Optimization Using Structural Causal Optimal Transport

Distributionally robust optimization tackles out-of-sample issues like overfitting and distribution shifts by adopting an adversarial approach over a range of possible data distributions, known as the ambiguity set. To balance conservatism and accuracy, these sets must include realistic probability distributions by leveraging information from the nominal distribution. Assuming that nominal distributions arise from a structural causal model with a directed acyclic graph G and structural equations, previous methods such as adapted and G-causal optimal transport have only utilized causal graph information in designing ambiguity sets. In this work, we propose incorporating structural equations, which include causal graph information, to enhance ambiguity sets, resulting in more realistic distributions. We introduce structural causal optimal transport and its associated ambiguity set, demonstrating their advantages and connections to previous methods. A key benefit of our approach is a relaxed version, where a regularization term replaces the complex causal constraints, enabling an efficient algorithm via difference-of-convex programming to solve structural causal optimal transport. We also show that when structural information is absent and must be estimated, our approach remains effective and provides finite sample guarantees. Lastly, we address the radius of ambiguity sets, illustrating how our method overcomes the curse of dimensionality in optimal transport problems, achieving faster shrinkage with dimension-free order.

Pseudogenes and host specialization in the emergent bacterial plant pathogen Xylella fastidiosa.

Pseudogenes are regarded as "junk" DNA, representing vestigial functions no longer needed for fitness. Accordingly, a higher number of pseudogenes in a bacterial human pathogen was previously hypothesized to be a hallmark of host specialists. In this study, we tested this hypothesis on the emergent bacterial plant pathogen Xylella fastidiosa (Xf) to link pseudogene makeup and host specificity. Xf is an ideal subject for these studies by being a xylem-limited pathogen that underwent extensive genome reduction. Using natural host range data of 151 strains and Pseudofinder analysis on Xf whole genome sequences, we observed that Xf subsp. sandyi had the highest pseudogene content, followed by subsp. morus, while subsp. pauca, fastidiosa, and multiplex had the lowest. The first two subspecies are known to have a limited host range compared to the others, aligning with the hypothesis of a greater number of pseudogenes corresponding to narrower host range. Weed isolates are presumably host specialists because they had the highest pseudogene content. Using a thorough pseudogene map across genomes and empirical pathogenicity data on blueberries, we screened for genes potentially involved in blueberry specialization. Targets were identified by selecting sequences pseudogenized (i) in strains infecting hosts different from blueberry and (ii) only in blueberry asymptomatic strains. Six sequences were identified with a potential role in blueberry infection, including one that was common between the two criteria. Here, we generated hypotheses on host range and specificity of Xf strains that need to be tested experimentally to help understand this devastating plant pathogen.IMPORTANCEXylella fastidiosa is a highly destructive plant pathogen that infects hundreds of landscape and agriculturally important plant species mainly in Europe and the Americas. Nevertheless, the host range of specific genotypes and underlying mechanisms of host specificity remain unclear. These are important aspects to determine the potential risk of infection in specific areas depending on the genetic makeup of the pathogen population and hosts present. This study offers valuable insights into the role of pseudogenization in the genomes of different X. fastidiosa strains, linking it to host specialization. Despite the limited information available for the host range of different strains of this pathogen, this research proposes a relationship between the abundance of pseudogenes and host specificity. These findings are essential for predicting potential host shifts by this pathogen, aiding in the development of strategies to prevent its spread. Additionally, the identification of candidate genes putatively important for symptom development in blueberries offers targets for prevention and control efforts.

The Evolution of Human-Earth Relationships in Southern Shaanxi during the Neolithic Period

The article explores the human-earth relationship in the Neolithic period in southern Shaanxi, especially the interrelationship between the land-use pattern, the cultural distribution range, and the evolution of the local natural environment, in terms of the size and shape of the settlement sites of the archaeological cultures, and the characteristics of the assemblage of the production tools. The results show that the land-use patterns responded to by the archaeological cultures in southern Shaanxi within the Neolithic period are consistent, the cultural distribution range is affected by climate change, and the distribution density is affected by the geographic environment. Under the condition of small changes in the overall natural environment, there is no obvious change in the shape of production tools and land use patterns within each culture, and the changes in microclimate within the southern Shaanxi region affect the distribution of the archaeological cultures as well as the geographic environment of the southern Shaanxi region affects the size of the distribution density of the cultures.

The first mayfly (Ephemeroptera, Baetidae) from Late Cretaceous amber of North Carolina, USA

Nowadays, Baetidae are among the most diverse and widespread mayfly families worldwide. However, fossil records of this family are very scarce, and each newly discovered specimen is of great importance for assessing the evolutionary history of this group. We report a newly discovered Baetidae fossil from the Cretaceous amber of North Carolina (USA), described herein as Petracloeon carolinensisgen. et sp. nov. The analysis of its morphology and a discussion of its possible affinities with already described Baetidae taxa (both fossil and extant) are provided. This represents the first mayfly from the North Carolina amber and the oldest Baetidae from the Americas. This finding also significantly expands the distribution range of Baetidae in the Cretaceous and supports the origin of the family prior to the main continental breakup beginning in the Jurassic.

An evaluation of migration fidelity of Ruby-throated Hummingbirds inferred from stable isotope methods.

Knowledge of spatial connectivity between breeding and non-breeding locations of migratory birds and their breeding site fidelity are important for avian conservation. Ruby-throated Hummingbirds (RTHU, Archilochus colubris) breed in eastern Canada west to the Rocky Mountains and in the USA east of the Mississippi River and spend the non-breeding period in Mexico, Central America, and southern Florida, USA. We measured the hydrogen and oxygen stable isotopic compositions of adult RTHU tailfeathers (fourth rectrix) from three breeding locations in North America to estimate migratory connectivity between breeding and non-breeding grounds where feathers are grown. Feather δ 2H values showed no statistical difference among the three sampling locations as well as disparate geographic assignments from one location on the non-breeding grounds in Costa Rica. Therefore, only weak evidence of migratory connectivity between breeding and non-breeding grounds could be ascertained for our sample of this species. The lack of migratory connectivity detected for Ruby-throated Hummingbirds using stable isotopes is consistent with origins from broad regions on the non-breeding grounds. However, it may also imply that precipitation δ 2H values on the non-breeding grounds do not vary enough to detect a difference among our study populations. Sampling of additional populations in the eastern and southern portion of the species' breeding range and the non-breeding grounds may reveal differences in migratory connectivity among populations and requires further investigation. The δ 18O values of feathers correlated poorly to their δ 2H values, an effect that may reflect the balance between metabolically driven processes and environmental water on the δ 18O values of hummingbird tissues. This study provides the foundations for further investigations into migratory connectivity of RTHU using δ 2Hf values and suggests potential avenues of study for use of δ 18O values of tissues in metabolic research.

Dispersal of invasive Berberis glaucocarpa in secondary forest occurs mainly by exotic frugivores

Understanding plant invasions is important in conservation ecology and land management, as invasive plant species worldwide have caused irreparable damage and often incur substantial control costs. To record the dispersal vectors for the invasive barberry (Berberis glaucocarpa) in a New Zealand regenerating forest, video cameras were used to film 24 barberry plants in fruit in Kowhai Bush, Kaikoura. During 242 hours of video, a total of 101 foraging events were recorded by four bird species: silvereye (Zosterops lateralis), blackbird (Turdus merula), song thrush (T. philomelos), and starling (Sturnus vulgaris). The four bird species varied in visitation frequency, time spent on plants, and fruit removal rates. The estimated daily contribution to recorded barberry fruit removal was 42.8% by song thrush, 32.6% by silvereye, 24.3% by blackbird, and 0.2% by starling. No endemic bird species were observed feeding on barberry, despite bellbirds (Anthornis melanura) being common in Kowhai Bush. Removal rates for ripe barberry fruit were relatively modest (1.14% per day), but given the ~3 month fruiting season, represented a sizable seed rain in the surrounding forest. Although barberry is now sympatric with several introduced frugivores in New Zealand, none of its dispersers from its native range in Nepal and northern India are present. Instead, dispersal in New Zealand is facilitated primarily by introduced European bird species and native silvereyes.

New horsetail macrofossils from the Lower Cretaceous of the Laiyang Basin, Eastern China, and biogeographic analyses

ABSTRACT Equisetum, the sole-living representative of Sphenopsida, is considered as a ‘living fossil’, with impressive species richness and a long fossil history dating back to the Devonian. It is regarded as a key taxon in attempting to understand the evolution of vascular plants. Here, we describe a new species, Equisetum shandongensis sp. nov. from the Early Cretaceous of the Laiyang Formation in Laiyang Basin, Shandong Province, eastern China. This species is the first record of horsetails from the Laiyang Basin, and it consists of relatively complete stems with distinct leaf sheaths, sporangiate spikes with helically arranged pentagonal sporangiophores, underground rhizomes, and tubers. The close affinity of our fossils to Equisetum is supported by the presence of both macromorphological and epidermal characters. This new species deepens our understanding of the diversity and distribution range of the early Equisetum in the Lower Cretaceous. The biogeographic distribution of Equisetum has been evaluated based on the phylogenetic and biogeographic analyses, which lead to the speculation that the subgenus Equisetum derived from the Laurasian clade no later than the Early Cretaceous.

The MSPE paradox is not only about MSPE!

ABSTRACT Recent literature demonstrates that traditional comparisons of Mean Squared Prediction Error (MSPE) between two competing forecasts may be controversial. This is so because, under certain inefficiency conditions, the forecast with the lowest MSPE coincides with the forecast displaying the lowest correlation with the target variable: this is known as ‘The MSPE Paradox’. In this paper, we show that this paradoxical result may also appear using another popular loss function: Mean Absolute Error (MAE). We show examples of this result for unbiased errors distributed as either Gaussian, t-Student, Uniform, and Logistic. We also present results for biased errors across a range of different distributions. We offer a characterization of ‘paradox zones’ and we further illustrate the relevance of the MAE Paradox with an empirical application when forecasting commodity returns.

Investigating the Distribution Dynamics of the Camellia Subgenus Camellia in China and Providing Insights into Camellia Resources Management Under Future Climate Change.

Rapid climate change has significantly impacted species distribution patterns, necessitating a comprehensive understanding of dominant tree dynamics for effective forest resource management and utilization. The Camellia subgenus Camellia, a widely distributed taxon in subtropical China, represents an ecologically and economically important group of woody plants valued for both oil production and ornamental purposes. In this study, we employed the BIOMOD2 ensemble modeling framework to investigate the spatial distribution patterns and range dynamics of the subgenus Camellia under projected climate change scenarios. Our analysis incorporated 1455 georeferenced occurrence records from 15 species, following the filtering of duplicate points, along with seven bioclimatic variables selected after highly correlated factors were eliminated. The ensemble model, which integrates six single species distribution models, demonstrated robust predictive performance, with mean true skil l statistic (TSS) and area under curve (AUC) values exceeding 0.8. Our results identified precipitation of the coldest quarter (Bio19) and temperature seasonality (Bio4) as the primary determinants influencing species distribution patterns. The center of species richness for the subgenus Camellia was located in the Nanling Mountains and eastern Guangxi Zhuang Autonomous Region. The projections indicate an overall expansion of suitable habitats for the subgenus under future climate conditions, with notable scenario-dependent variations: distribution hotspots are predicted to increase by 8.86% under the SSP126 scenario but experience a 2.53% reduction under the SSP585 scenario. Furthermore, a westward shift in the distribution centroid is anticipated. To ensure long-term conservation of Camellia genetic resources, we recommend establishing a germplasm conservation center in the Nanling Mountains region, which represents a critical biodiversity hotspot for this taxon.

Predicting the invasion of the common wall gecko (Tarentola mauritanica) in the southern cone of South America

ABSTRACT The common wall gecko (Tarentola mauritanica) has invaded three regions globally: the Azores and Madeira archipelagos, the subtropical and temperate regions of North America, and the south of South America. The information about the invasion in South America is limited, and records suggest rapid expansion in the continent’s south. In this work, we modeled the gecko’s distribution in its native range to identify potential invasion sites in the Southern Cone of South America, updating its geographic distribution and assessing their potential threat to native South American geckos. The most contributive variables in the Species Distribution Model included precipitation of the driest quarter, minimum temperature of the coldest month, and temperature seasonality. The habitat suitable for the expansion of geckos in the Southern Cone covers 1,397,558.36 km2, with the highest being in the north-central part of Argentina. The species Homonota taragui, Homonota williamsii, and Homonota whitii had the greatest degree of overlap with the suitable habitat of T. mauritanica, requiring particular caution against future introductions. This underscores the importance of understanding and mitigating the risks associated with the invasive potential of T. mauritanica in the Southern Cone of South America, specially to the endemic and endangered species, living in rocky areas.

Divergence of Two Diospyros Species Promoted by Geo‐Climatic Processes Across Dry Valleys and Lowlands in Subtropical China

ABSTRACTAimExploring the divergence and speciation processes is central to understanding the origin and maintenance of biodiversity. The dry valley mosaic in the Hengduan Mountains and its southern extension range is one of the special landscapes globally and harbours a high level of endemic plants of tropical margin nature. The dry valleys and lowlands‐adapted plants constitute a unique system to explore how the geological and ecological effects have shaped the speciation processes here.LocationSubtropical China.TaxonDiospyros dumetorum and Diospyros saxatilis.MethodsWe surveyed patterns of genetic variation from 33 populations spanning their distribution ranges using three chloroplast DNA fragments and eight nuclear microsatellite loci. Approximate Bayesian computation was conducted to compare population demographic models considering gene flow and to estimate key parameters. We used Ecological Niche Models (ENMs) to reconstruct changes in range distribution during glacial and interglacial periods and evaluate their niche differentiation.ResultsPlastid and nuclear data strongly support divergence between the two species occurring during the Pliocene/Pleistocene period followed by secondary contact in response to climatic oscillations. ENMs predicted drastic distribution range changes during the Quaternary and identified significant differences in climatic conditions at the set of locations occupied by these two species. Correlation analyses were conducted, and the results suggest that geographical isolation rather than environmental heterogeneity shapes the current population genetic structure within the two species.Main ConclusionPhylogeographical patterns revealed in our results document that geographic vicariance associated with tectonic uplifts initiated allopatric species divergence between the two dry valleys and lowlands‐adapted Diospyros species, and niche differentiation perhaps further accelerated the speciation processes with limited subsequent gene flow. Our findings could contribute to the knowledge of forces that drive speciation processes in the unique landscape of dry valleys, as well as the evolution of the flora in subtropical China.

Uncertainty Quantification of Geophysical and Hydrologic Parameters Estimated From Borehole Nuclear Magnetic Resonance Data

AbstractBorehole nuclear magnetic resonance (bNMR) data are typically used to infer in situ hydrologic properties. Partial water content as a function of pore size is estimated by fitting the measured NMR response to a multi‐exponential T2 distribution, and the sum of estimated T2 amplitudes equals the total volumetric water content. From these estimated parameters, several empirical relationships are commonly used to infer hydraulic conductivity from the NMR‐estimated water content and T2 distribution. Often, parameters are estimated through deterministic inversion methods that produce a single best‐fit estimate, but do not reflect uncertainties in model parameters. Here, a Bayesian Markov chain Monte Carlo (McMC) approach for analyzing bNMR data is developed that allows for comprehensive uncertainty quantification of NMR parameters and derived hydrologic properties. The underlying model that describes the T2 distribution is defined by a set of spline interpolation points. The number of interpolation points is allowed to vary in a trans‐dimensional algorithm that naturally favors simple models with fewer interpolation points, allowing the data to inform the necessary level of model complexity. Additionally, data error is estimated as an unknown parameter. Analysis of the ensemble of models output from the McMC algorithm provides useful details on the range of plausible T2 distributions that can fit a measured bNMR decay curve, as well as uncertainty estimates of total water content. The ensemble of NMR parameters can also be propagated through commonly used relationships to produce uncertainty estimates on derived parameters such as bound/capillary/mobile water content or hydraulic conductivity.

First report of Dactylogyrus fimbriphallus (El Gharbi, Birgi & Lambert, 1994) infecting Luciobarbus biscarensis (Boulenger, 1911) in Oued Tadmit River of Djelfa Governorate (Algeria)

This study aimed to determine the occurrence of dactylogyrid communities in Sahara barbel, Luciobarbus biscarensis (Boulenger, 1911), an endemic species to Algeria, according to season and host factors. A total of 78 samples of L. biscarensis were collected seasonally, over four seasons from 2023 to 2024, from Oued Tadmit River in Djelfa Governorate with the help of local fishermen. Thirty-three L. biscarensis were infected with one or more individuals of dactylogyrid parasites (42.31%), and a total of 306 individuals were recorded. All monogenean species collected from the gills of the host fish were identified based on the presence of the following morphometric characteristics: two pairs of anchors, dorsal bar, ventral bar, vaginal armament and copulatory tube. Only one Dactylogyrus species, Dactylogyrus fimbriphallus (El Gharbi, Birgi & Lambert, 1994), was found on the gills. The mean intensity and abundance were 9.27 ± 12.50 parasites per fish and 3.92 ± 9.28, respectively. The infection levels of D. fimbriphallus were also investigated in relation to length and sex of the host fish as well as seasons, and the differences in its prevalence, mean intensity and mean abundance were statistically evaluated. There were significant differences in prevalence, mean intensity and abundance values between seasons. The infestation rate was higher in female hosts than in males. The host fish represents a new host record for D. fimbriphallus and new insights into the geographical distribution and host range have been gained. This study highlights the need for further research on helminth parasites, particularly monogeneans, affecting Algerian freshwater fishes, given the limited existing data.

3D geological model reconstruction and collapse risk evaluation of old goaf in Dunqiu iron mine

The complexity of goafs put forward higher requirements for detection methods. A comprehensive detection method for old goaf is proposed, that is, determining the plane distribution range of old goaf by using high-precision magnetic method, determining the horizon of old goaf by using natural source surface wave method and controlled source audio magneto telluric method, and modifying the geophysical exploration results by using engineering drilling. Taking the old goaf of Dunqiu iron mine of China as an engineering background, the comprehensive detection method is successfully applied. The plane areas of goaf formed by mining of No. 1–3 orebody groups are 8640.6 m2, 4992.5 m2 and 6740.4 m2 respectively. The goaf can be divided into pure goaf and backfill goaf, which is 1–7 layers, 30.2–115.0 m buried depth, and 1.6–271.3 m mining thickness. A 3D geological model is constructed for displaying the situation of goaf visually. The goaf volumes of No. 1–3 orebody groups are 159,187.13 m3, 125,604.57 m3 and 174,435.28 m3 respectively. The stability of old goaf is evaluated by using two methods: influence depth of critical load and depth-thickness ratio of goaf, which is poor and has a risk of collapse. The detection method and results have certain guiding significance for the detection and treatment of old goaf in iron mine.

Distribution pattern of different volumes of ropivacaine in ultrasound-guided intertransverse process block: a randomized, blinded, computed tomography imaging study

BackgroundIntertransverse process (ITP) blocks showed reliable paravertebral spread in cadaveric studies, but specific distribution patterns, spread pathways, and dose‒effect relationships remain unclear. The aim of this study was to evaluate the distribution patterns of three different volumes of local anesthetic (LA) in ITP block in living humans using computed tomography.MethodsForty-five individuals (18–75 years old) were randomized to receive 0.375% ropivacaine with radiopaque contrast agent at doses of 0.3, 0.4, or 0.5 ml/kg. The primary outcome was the distribution of LA in mediastinal compartments (prevascular, visceral, and paravertebral), retro-superior costotransverse ligament space, erector spinae fascia plane, intercostal space, sympathetic ganglion, costotransverse space, intervertebral foramen, lateral recess, and epidural space. The secondary outcomes included intraoperative and postoperative VAS scores, dermatomal sensory loss, block-related adverse events, and the time required for block administration.ResultsThe spread pattern of local anesthetic after intertransverse process block includes both forward and backward spread. The LA was concentrated in the visceral compartment (77.5%), paravertebral compartment (93.3%), erector spinae fascia plane (97.8%), intercostal space (97.8%), and sympathetic ganglion (88.9%), with occasional spread to other areas. The overall distribution pattern was significantly influenced by patient position (R2 = 0.07, F. Model = 3.43, P = 0.04) rather than anesthetic volume (R2 = 0.03, F. Model = 1.60, P = 0.20) and BMI category (R2 = 0.03, F. Model = 1.36, P = 0.26). The LA was concentrated in the prevascular compartment when the patient position was changed in the prone position (B = 2.45, 95% CI [0.96, 3.95], P = 0.002). There were no differences in secondary outcomes.ConclusionsITP block causes the LA to predominantly spread to the paravertebral compartment, visceral compartment, intercostal space, sympathetic ganglion, and erector spinae fascia plane. Within the range of volumes studied (0.3, 0.4, and 0.5 ml/kg), increasing the LA volume did not result in a wider distribution range; the overall distribution pattern was primarily influenced by patient positioning.Trial registrationThe trial was registered online on 3 April 2024 in the Chinese Clinical Trial Registry (ChiCTR2400082665).

Large Inversions Shape Diversification and Genome Evolution in Common Quails

ABSTRACTChromosomal inversions, by suppressing recombination, can profoundly shape genome evolution and drive adaptation. In the common quail (Coturnix coturnix), a highly mobile bird with a vast Palearctic breeding range, we previously identified a massive inversion on chromosome 1 associated with distinct phenotypes and restricted geographic distribution. Here, using a new de novo genome assembly, we characterise this inversion and uncover additional, ancient structural variation on chromosome 2 that segregates across the species' range: either two putatively linked inversions or a single, large inversion that appears as two due to scaffolding limitations. Together, the inversions encompass a remarkable 15.6% of the quail genome (153.6 Mbp), creating highly divergent haplotypes that diverged over a million years ago. While the chromosome 1 inversion is linked to phenotypic differences, including morphology and migratory behaviour, the chromosome 2 inversion(s) show no such association. Notably, all inversion regions exhibit reduced effective population size and a relaxation of purifying selection, evidenced by elevated nonsynonymous‐to‐synonymous substitution ratios (N/S). This suggests that inversions, particularly the geographically restricted one on chromosome 1, may act as engines of diversification, accelerating the accumulation of functional variation and potentially contributing to local adaptation, especially within isolated island populations. Our findings demonstrate how large‐scale chromosomal rearrangements can compartmentalise a genome, fostering distinct evolutionary trajectories within a single, highly mobile species.

EDNA Assessment of the Diamond Darter (Crystallaria cincotta) in its Current and Historic Distribution Range

Investigations of Diamond Darter (Crystallaria cincotta) distributions through environmental DNA (eDNA) sampling may serve as an emergent monitoring tool specifically for this species. The Diamond Darter is a federally endangered fish of the Ohio River basin extant only in West Virginia. The cryptic behavior and incomplete comprehension of this species serve as perfect grounds to test if eDNA can serve as an efficient means of species detection. The objective of this study was to determine Diamond Darter occupancy within current and historical distributions of its range through eDNA investigations with a potential for alterations in the species’ current recognized range. We developed a unique single nucleotide polymorphism (SNP) that identifies Diamond Darter DNA distinctly from 23 other Percid species including the Crystal Darter (Crystallaria asprella). Collected eDNA was paired against this SNP to identify locations where the organism persists. Various locations throughout the current and historical ranges of the Diamond Darter were sampled through water filtrations and examined to determine presence of target species DNA. 137 samples across 38 sites in six watersheds among four states were administered resulting in multiple positive detections primarily within the current critical habitat designation of the lower Elk River in West Virginia. Follow-up nighttime spotlight surveys at positive detection sites proved successful at observing Diamond Darter individuals, as well as the discovery of a new site locality for the species. Ultimately, our sampling efforts have provided sound evidence supporting significant contributions towards conservation efforts and distribution mapping of the Diamond Darter through eDNA.