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The article discusses the impact of population size, structure, fertilization success, and propagule dimorphism on sex allocation in simultaneous hermaphrodites, focusing on plant reproduction. The authors present a mathematical model that challenges classical sex allocation theory by showing that population size, pollen mortality, and fertilization success can influence sex allocation. The study reanalyzes the model and confirms the classical result of equal sex allocation under panmixia. The research highlights the importance of considering population structure and dispersal rates in understanding sex allocation evolution. [Extracted from the article]

Clinostomum species, a parasitic pathogen of freshwater fish, is widely distributed and infects various host species. Recently, the pathological effect due to Clinostomum metacercarial infection was described in aquaculture in Thailand; however, the global genetic diversity and population structure of this species have not been studied yet. Therefore, this study aimed to provide a detailed description of genetic diversity and population dynamics of the digenean Clinostomum isolated from Trichopodus pectoralis with globally recorded Clinostomum species. The species was characterized molecularly by analyzing 18S rDNA and inter‐transcribed spacer biomarker genes (ITS1 and ITS2). A BLAST search discovered that the 18S rDNA and ITS sequence had a 100% sequence similarity with Clinostomum piscidium isolated from India and Thailand. A comprehensive analysis revealed the presence of 12 distinct haplotypes among the Clinostomum populations. This study suggests that distinct patterns of genetic variation were identified by analyzing molecular variance, pairwise Fst, and employing structure analysis. It was observed that a gradient of genetic variation exists within continents, characterized by higher levels within different groups and lower levels of genetic differentiation. Additionally, a notable presence of mixed haplotypes was observed. The results of neutrality testing suggest that there has been a significant expansion in the populations of Clinostomum in India, America, and Kenya. The discoveries from this study will provide a valuable contribution to comprehending the genetics and evolution of Clinostomum species. Furthermore, key findings will be essential in developing efficient management approaches to prevent and control this parasite. [ABSTRACT FROM AUTHOR]

ABSTRACT The expansion of human settlements over the past few centuries is responsible for an unprecedented number of invasive species introductions globally. An important component of biological invasion management is understanding how introduction history and postintroduction processes have jointly shaped present‐day distributions and patterns of population structure, diversity and adaptation. One example of a successful invader is the European starling (Sturnus vulgaris), which was intentionally introduced to numerous countries in the 19th century, including Aotearoa New Zealand, where it has become firmly established. We used reduced representation sequencing to characterise the genetic population structure of the European starling in New Zealand, comparing it to that present in sampling locations in the native range and invasive Australian range. The population structure and genetic diversity patterns we found suggested restricted gene flow from the majority of New Zealand to the northmost sampling location (Auckland). We also profiled genetic bottlenecks and shared outlier genomic regions, which supported historical accounts of translocations between both Australian subpopulations and New Zealand, and provided evidence of which documented translocation events were more likely to have been successful. Using these results as well as historic demographic patterns, we demonstrate how genomic analysis complements even well‐documented invasion histories to better understand invasion processes, with direct implications for understanding contemporary gene flow and informing invasion management. [ABSTRACT FROM AUTHOR]

Subnational divergence in the age and sex structures of populations can have far‐stretching consequences for development: from marriage markets to the potential for violence to economic growth. With urbanization and the demographic transition still underway, rural and urban populations continue to differ across low‐ and middle‐income countries. We examine the extent by which internal migration contributes to these differences, from 1970 to 2014 using estimates of migration between rural and urban sectors based on census data from 45 countries. We found that despite heavily delineated migration profiles by age and sex, internal migration does not alter sex and age structures of rural and urban populations. All the same, internal migration does increase urban growth in Asia and Latin America and the Caribbean. In contrast, in Africa, internal migration has little leverage with the urban transition. Across the continents, there is a potential for de‐urbanization, driven by a rural/urban gap in fertility. As such, the rural population may continue to constitute a significant proportion of national populations, necessitating critical investments to ensure they are not left behind. [ABSTRACT FROM AUTHOR]

Species translocations are increasingly being used in conservation and for biological control. The success of a translocation can be strongly influenced by the evolutionary processes occurring during the early phase of the introduction and the subsequent spread to new regions. In this study, morphological variation and population genetic structure were assessed in the African dung beetle Digitonthophagus gazella, a species that was intentionally introduced to Australia for biological control in 1968 and subsequently spread widely across the northern part of the continent. A dataset based on 1594 neutral single nucleotide polymorphism (SNP) loci that were genotyped in 187 individuals from 12 sites revealed significant genetic divergences between sites (global FST = 0.118) and provides evidence of restricted gene flow among established populations at small to moderate spatial scales (74–500 km). Geometric morphometric analyses revealed significant divergence among populations in the shape of the foretibia, a trait ecologically important for tunnelling in soil and dung. Moreover, phenotypic divergence in this trait for both sexes was significantly higher than genetic differentiation at selectively neutral loci (PST > FST), suggesting that directional selection is contributing to the phenotypic divergences among populations. Our study shows how population structure can establish quickly in an introduced species and highlights the importance of considering local adaptation when performing translocations on established populations. [ABSTRACT FROM AUTHOR]

Potential immortality is observed in several species (e.g. prickly pear cactus, hydra and flatworms) and is indicative of their negligible or even negative senescence rates. Unlike in senescent species, which experience reduced individual performance with age due to physiological degradation, species with negligible or negative senescence display mortality rates that remain constant or decline with age, respectively. These rates vary across taxa and are correlated with life history traits. Yet, the extent to which variable resource availability, a key driver of variation in life history traits, impacts species that show negligible or negative senescence is currently unknown.Here, we examine whether and how variation in the quantity, quality and feeding interval of resources impact population structure, population performance and life history trait trade‐offs in two long‐lived planaria that do not senesce: Schmidtea mediterranea and Dugesia tahitiensis. In a full factorial design, different combinations of resource quantity (reduced intake, standard intake and high intake) and quality (high and low quality) were provided in two different feeding intervals (7‐day and 14‐day intervals) for 19 weeks.We show that variability in resource availability, via decreases in quantity, quality and frequency of resources, does not diminish population viability in either species but does result in suboptimal conditions of stress in S. mediterranea.The high population viability we report can be attributed to two different mechanisms: increased reproduction or increased investment into maintenance at the expense of reproduction. Moreover, which mechanism was responsible for said high population viability was context‐dependent and modulated by the specific life history strategy of the two planaria species.We show that suboptimal conditions can cause stress responses that have significant impacts on non‐senescent species. The context‐dependent response we observe suggests that species that do not senesce but are subject to suboptimal conditions of stress may ultimately exhibit declines in performance and ultimately die. A clearer understanding of the impact of suboptimal conditions of resource availability on non‐senescent species is needed to determine the extent of stress experienced and ultimately whether a species can truly be immortal. [ABSTRACT FROM AUTHOR]

ABSTRACT Isolation by distance and biogeographical boundaries define patterns of population genetic structure for harbour porpoise along the Pacific coast from California to British Columbia. Until recently, inadequate sample sizes in many regions constrained efforts to characterise population genetic structure throughout the coastal waters of Alaska. Here, tissue samples from beachcast strandings and fisheries bycatch were supplemented with targeted environmental DNA (eDNA) samples in key regions of Alaska coastal and inland waters. Using a geographically explicit, hierarchical approach, we examined the genetic structure of Alaska harbour porpoises, using both mitochondrial DNA (mtDNA) sequence data and multilocus SNP genotypes. Despite a lack of evidence of genetic differentiation from nuclear SNP loci, patterns of relatedness and genetic differentiation from mtDNA suggest natal philopatry at multiple geographic scales, with limited gene flow among sites possibly mediated by male dispersal. A priori clustering of sampled areas at an intermediate scale (eastern and western Bering Sea, Gulf of Alaska and Southeast Alaska) best explained the genetic variance (12.37%) among regions. In addition, mtDNA differentiation between the Gulf of Alaska and eastern Bering Sea, and among regions within the Gulf of Alaska, indicated significant genetic structuring of harbour porpoise populations in Southeast Alaska. The targeted collection of eDNA samples from strata within Southeast Alaska was key for elevating the statistical power of our mtDNA dataset, and findings indicate limited dispersal between neighbouring strata within coastal and inland waters. These results provide evidence supporting a population boundary within the currently recognised Southeast Alaska Stock. Together, these findings will prove useful for ongoing management efforts to reduce fisheries conflict and conserve genetic diversity in this iconic coastal species. [ABSTRACT FROM AUTHOR]

Norway lobster Nephrops norvegicus, a prized decapod crustacean species, is found at different depths across the East Atlantic Ocean and Mediterranean Sea. Despite management efforts, the stocks are globally characterised as overexploited. In the present study, the impact of biogeographical boundaries on the phylogeographical and demographic population status was investigated within the Adriatic Sea, addressing important genetic indices for decapod functional conservation management. Central Mediterranean, Adriatic Sea A total of 482 individuals of Nephrops divided into the 12 samples were collected across biogeographical range of the Adriatic Sea. Using the mtDNA D‐loop and microsatellite markers, methods of phylogeography and seascape genetics were applied to infer offshore versus coastal population divergence, demography and structure. Significant findings include genetic differentiation between offshore and coastal samples, with higher diversity indices in open waters. The limited gene flow observed between these two areas emphasises the self‐sustained nature of coastal populations. Recent demographic changes in coastal populations reflect geographical constraints, fishing pressures and fluctuations in self‐recruitment success. Additionally, the study reveals historical biogeographic events shaping the Adriatic populations, with evidence suggesting lineage divergence during the upper Pleistocene and postglacial recolonisation from southern Adriatic refugia. The role of biogeographical conditions in shaping genetic structure and limited gene flow between inshore and offshore areas underscore the need for improved management strategies, emphasising the importance of marine protected areas in conserving coastal populations and maintaining overall genetic diversity of the Norway lobster in the Adriatic Sea. Genomic monitoring within current management practices is recommended. [ABSTRACT FROM AUTHOR]

An important consequence of the discontinuous distribution of insect populations within their geographic range is phenotypic divergence. Detection of this divergence can be challenging when it occurs through subtle shifts in morphological traits with complex geometries, such as insect wing venation. Here, we used landmark‐based wing geometric morphometrics to investigate the population‐level phenotypic variation of the two subspecies of Glossina morsitans, G. m. centralis Machado and G. m. morsitans Westwood that occur in Zambia. Twelve homologous landmarks digitised on the right wings of 720 specimens collected from four and five sites (80 per site with 1:1 sex ratio) within the G. m. centralis and G. m. morsitans range respectively, were subjected to generalised Procrustes analysis to obtain wing centroid size (CS) and wing shape variables. Linear permutation models and redundancy analysis were then used to compare CS and wing shape between male and female G. morsitans, the two subspecies G. m. centralis and G. m. morsitans, the sexes of each subspecies and between sample locations within each subspecies range, respectively. Significant differences in CS and wing shape were observed between G. morsitans sexes, subspecies and sample locations within each subspecies range. A neighbour‐joining cladogram derived from the analysis of Procrustes distances showed that tsetse within each subspecies range were highly divergent. We conclude that G. morsitans populations in Zambia exhibit significant population‐level variation in fly size and wing shape which suggests high levels of population structuring. The main drivers of this structuring could be random genetic drift in G. m. centralis demes and local adaptation to environmental conditions in G. m. morsitans populations. We therefore recommend molecular studies to estimate the levels of gene flow between these populations and identify possible barriers to genetic flow. [ABSTRACT FROM AUTHOR]

Domestication has shaped the population structure and agronomic traits of tea plants, yet the complexity of tea population structure and genetic variation that determines these traits remains unclear. We here investigated the resequencing data of 363 diverse tea accessions collected extensively from almost all tea distributions and found that the population structure of tea plants was divided into eight subgroups, which were basically consistent with their geographical distributions. The genetic diversity of tea plants in China decreased from southwest to east as latitude increased. Results also indicated that Camellia sinensis var. assamica (CSA) illustrated divergent selection signatures with Camellia sinensis var. sinensis (CSS). The domesticated genes of CSA were mainly involved in leaf development, flavonoid and alkaloid biosynthesis, while the domesticated genes in CSS mainly participated in amino acid metabolism, aroma compounds biosynthesis, and cold stress. Comparative population genomics further identified ~730 Mb novel sequences, generating 6,058 full‐length protein‐encoding genes, significantly expanding the gene pool of tea plants. We also discovered 217,376 large‐scale structural variations and 56,583 presence and absence variations (PAVs) across diverse tea accessions, some of which were associated with tea quality and stress resistance. Functional experiments demonstrated that two PAV genes (CSS0049975 and CSS0006599) were likely to drive trait diversification in cold tolerance between CSA and CSS tea plants. The overall findings not only revealed the genetic diversity and domestication of tea plants, but also underscored the vital role of structural variations in the diversification of tea plant traits. [ABSTRACT FROM AUTHOR]

We implement a population genetics approach to clarify the role that temporal and environmental variability, spatially distinct locations and different hosts may have in the epidemiology of a plant disease and in the microevolution of its causative pathogen. In California and southern Oregon (USA), the introduction of the invasive pathogen Phytophthora ramorum, causal agent of the widespread disease Sudden Oak Death (SOD), has resulted in extensive mortality of various oaks Quercus sp. and of tanoak Notholithocarpus densiflorus. Although the disease can infect over a hundred hosts, California bay laurel Umbellularia californica is the most competent transmissive host but is not lethally affected by the disease. Using population genetics data, we identify the relationship among P. ramorum populations in bay laurels, oaks and tanoaks to clarify the contribution of each host on the epidemiology of SOD and on the microevolution of its causal agent and to explore differences in population structure across sites and years. We conclude that bay laurel is the primary source for infections of both tanoak and oak, and that tanoak contributes minimally to oak infection but can infect bay laurel, creating a secondary pathogen amplification process. Overall, pathogen diversity is associated with rainfall and presence of bay laurels, which sustain the largest populations of the pathogen. Additionally, we clarify that while bay laurels are a common source of inoculum, oaks and tanoaks act as sinks that maintain host‐specific pathogen genotypes not observed in bay laurel populations. Finally, we conclude that different sites support a dominance of different pathogen genotypes. Some genotypes were widespread, while others were limited to a subset of the plots. Sites with higher bay laurel densities sustained a higher genotypic diversity of the pathogen. This work provides novel insight into the ecology and evolutionary trajectories of SOD epidemics in natural ecosystems. [ABSTRACT FROM AUTHOR]

Summary: Understanding how life history shapes genetic diversity is a fundamental issue in evolutionary biology, with important consequences for conservation. However, we still have an incomplete picture of the impact of life history on genome‐wide patterns of diversity, especially in long‐lived semelparous plants.Puya raimondii is a high‐altitude semelparous species from the Andes that flowers at 40–100 years of age. We sequenced the whole genome and estimated the nucleotide diversity of 200 individuals sampled from nine populations. Coalescent‐based approaches were then used to infer past population dynamics. Finally, these results were compared with results obtained for the iteroparous species, Puya macrura.The nine populations of P. raimondii were highly divergent, highly inbred, and carried an exceptionally high genetic load. They are genetically depauperate, although, locally in the genome, balancing selection contributed to the maintenance of genetic polymorphism. While both P. raimondii and P. macrura went through a severe bottleneck during the Pleistocene, P. raimondii did not recover from it and continuously declined, while P. macrura managed to bounce back.Our results demonstrate the importance of life history, in particular generation time and reproductive strategy, in affecting population dynamics and genomic variation, and illustrate the genetic fragility of long‐lived semelparous plants. [ABSTRACT FROM AUTHOR]

Understanding animals' movements is essential to assess habitat use, life‐history strategies, and population dynamics. Here, we investigate the movement and behavior patterns of 153 humpback whales in the Southwest Atlantic Ocean (SWA) using data obtained by satellite telemetry between 2003 and 2019 during the species' breeding season (August–December) off the Brazilian coast. Switching state space models were applied to estimate behavior states (bmode) classified as Area Restricted Search (ARS), Transiting (TRANS), or uncertain. Whales were distributed from 4°S to 24°S, and five clusters of ARS behavior were identified along the Brazilian coast. Generalized linear mixed modeling revealed three main results: (1) a transition towards more sinuous behavioral states with increasing latitude; (2) more sinuous movement behavior around new moons; (3) movement behavior was temporally dynamic throughout the breeding season over the years, particularly in 2019. The results then revealed important regions where humpback whales cluster to engage in mating and nursing behaviors, highlighting the influence of spatial location and environmental cycles on their behavior. Estimated movement behavior presented here improves the knowledge about the habitat use and movement patterns of SWA humpback whales in their breeding ground and can be used to mitigate potential human‐related impacts. [ABSTRACT FROM AUTHOR]

Because populations are at the mercy of random disturbances large and small, they rarely, if ever, converge on predicted long‐term behaviors. Therefore, when employing matrix population models, ecologists study the dynamics of populations that depart from stable distributions. Necessary for such studies are indices of transient dynamics that measure the size of short‐term population fluctuations. These indices advance our understanding of population dynamics by revealing that population growth rate in a single timestep can far exceed the stable population growth rate. Despite their value, indices of transient behavior possess two major shortcomings: they are scale dependent and easily distorted by outsized population classes. Distortion occurs whenever immature classes, due to their sheer size, carry greater weight in the calculation of population size than mature classes. Beluga sturgeon (Huso huso), for example, have an immature age class (eggs) that is several orders of magnitude larger than its mature age classes. To remove the undue influence of outsized classes, I use balancing, which rescales classes by the stable population distribution and makes the indices of transient dynamics scale invariant. I apply balancing to 1800 population projection matrices for various species across the Animal Kingdom, using reactivity and the Henrici metric of non‐normality as indices of transient dynamics. I found that balancing profoundly changes the picture of which populations have the greatest or least potential transient dynamics. Using a population projection matrix for northern pike (Esox lucius), I demonstrate how balancing influences pseudospectra contour plots that are used to infer transient dynamics. [ABSTRACT FROM AUTHOR]

Aim: The Amazon rainforest is one of the most biodiverse regions on earth, but our understanding of the processes that have shaped its patterns of diversity remains incomplete. One hypothesis for Amazonian speciation is the river‐refuge hypothesis, which suggests that retraction of forests away from the periphery of Amazonia, where rivers are narrow, facilitated divergence of populations separated by wide rivers. Later re‐expansion of forests would have allowed secondary contact between these populations, and co‐occurring hybrid zones may reveal the location where expanding forests first reconnected. Here, we test whether a widespread Amazonian songbird species shows evidence of population contact zones in the eastern headwaters of the Tapajós river, hypothesised to be an area of secondary contact under the river‐refuge hypothesis. Location: Amazon and Atlantic forests of South America. Taxon: Ceratopipra rubrocapilla (Pipridae, Passeriformes). Methods: We sampled 147 C. rubrocapilla (Red‐headed Manakin) across its vast range, with 70 samples sequenced using reduced‐representation genomic sequencing and 139 sequenced at the mitochondrial gene cytochrome b. We use population genetic and phylogenetic analyses to investigate patterns of gene flow and population structure across the range, with a particular focus on samples from the headwaters of the Tapajós River to evaluate the potential role of the river‐refuge hypothesis. Results: We observe shallow population structure and evidence for widespread gene flow across the range of C. rubrocapilla. Patterns in the Tapajós headwaters match predictions of the river‐refuge hypothesis, with eastern headwater samples most similar to samples farther west on the opposite bank of the Tapajós River. Main Conclusions: The close co‐occurrence between population contact zones within C. rubrocapilla and other previously studied hybrid zones reinforces the hypothesis that the eastern Tapajós headwaters is where rainforest populations reconnected in the past, following predictions of the river‐refuge hypothesis of Amazonian speciation. [ABSTRACT FROM AUTHOR]

Invasive species are one of the main threats to global biodiversity and, within marine ecosystems, tunicates feature some prominent examples. Styela plicata is an ascidian species inhabiting harbours in all temperate oceans and seas, thus being considered a thriving invasive species. However, this species' adaptive mechanisms, introduction history, and population structure have never been completely elucidated. Here, by genotyping 87 S. plicata individuals from 18 localities worldwide with 2b‐RADseq, we confirm the global presence of four chromosome inversions, demonstrate population structuring on this species, detect local adaptation signals, and infer historical demographic events. We show that North Carolina individuals constitute an unrelated population, Atlanto‐Mediterranean and Pacific localities form their own genetic clusters with substructuring, being the most evident the split between northern and southern Atlantic localities. The locality of South Carolina presents an intermediate genetic position between North Carolina and the other two groups pointing to a hybrid origin with recurrent gene flow. We generate and test demographic models, providing evidence of two independent introduction events to the Atlantic and Pacific, and an admixture that originated the population of South Carolina. Finally, we identify candidate loci for adaptation, with functions involved with cell processes, metabolism, development, and ion transport, among others. Overall, this study highlights the complex historical processes of S. plicata, which have led this species to its current distribution, population structure, and local adaptation footprint in oceans worldwide. [ABSTRACT FROM AUTHOR]

Among the flower beetles (Scarabaeidae, Cetoniinae), the Goliathini comprise several genera of medium‐ and large‐sized beetles widely distributed in sub‐Saharan Africa. In this tribe, the genus Fornasinius Bertoloni, 1853, includes two species found in West Africa: F. higginsi (Westwood) and F. klingbeili Zöller, Fiebig,and Schulze. In this study, we present new data on the comparative ecology and biogeography of these two species, including sex ratio, population structure by size, monthly activity patterns and habitat features at two different spatial scales. These observations were conducted, mostly opportunistically, over a 20‐year period in Cote d'Ivoire, Ghana and Togo. Both species exhibited similar overall population structure and morphometrics. They were characterised by a male‐skewed adult sex ratio (with possible bias), male‐larger sexual size dimorphism and consistent population structure by size; the two species are seemingly parapatric (with the potential contact zone being separated in eastern Ghana by the Volta River and Volta Lake). Both are primarily found in the vicinity of trees that contained middens of hyraxes, such as Dendrohyrax dorsalis (F. higginsi), Dendrohyrax interfluvialis (F. klingbeili) and Procavia capensis (F. klingbeili). F. higginsi has been primarily observed in forest habitat, while F. klingbeili was found in both forests and Guinea savannahs. Occurrence sites of F. higginsi were predominantly characterised by higher tree cover, less bare areas and built‐up zones. Although these beetles may be locally abundant within hyrax middens, they typically occur in only a relatively small number of sites within their preferred habitat. Monthly activity patterns differed between the two species. Although adults of both species were observed throughout the year, sightings of F. higginsi were more common during the wet season, whereas F. klingbeili sightings were more frequent in the dry season. The observed differences in monthly activity patterns between these ecologically and morphologically similar species may help to minimise interspecific competition in potential—yet unknown—sites of syntopy. Although some Fornasinius populations might be locally threatened by deforestation or overhunting of hyraxes, the careful management of hyrax populations should adequately ensure the conservation of these two beetle species. [ABSTRACT FROM AUTHOR]

Gene flow is important for maintaining the genetic diversity required for adaptation to environmental disturbances, though gene flow may be limited by site fidelity in small coastal sharks. Bonnethead sharks (Sphyrna tiburo)—a small coastal hammerhead species—demonstrate site fidelity, as females are philopatric while males migrate to mediate gene flow. Consequently, bonnetheads demonstrate population divergence with distance, and Atlantic populations are genetically distinct from those of the Gulf of Mexico. Indeed, Florida forms a vicariant zone between these two bodies of water for many marine species, including some sharks. However, while bonnetheads are expected to have limited dispersal, the extent and rate of bonnethead migration remain uncertain. Thus, we aimed to determine their dispersal capacity by evaluating connectivity between disparate populations from the Gulf of Mexico and Atlantic Ocean. Using 10,733 SNPs derived from 2bRAD sequences, we evaluated genetic connectivity between Tampa Bay on the Gulf Coast of Florida and Biscayne Bay on the Atlantic coast of Florida. While standard analyses of genetic structure revealed slight but significant differentiation between Tampa Bay and Biscayne Bay populations, demographic history inference based on the site frequency spectrum favored a model without divergence. However, we also estimate that if population divergence occurred, it would have been recent (between 1500 and 4500 years ago), with continuous unidirectional gene flow from Tampa Bay to Biscayne Bay. Our findings support the hypothesis that bonnetheads can migrate over relatively large distances (>300 miles) to find mates. Together, these results provide optimism that under proper management, a small‐bodied globally endangered shark can undergo long migrations to sustain genetic diversity. [ABSTRACT FROM AUTHOR]

Most plant phylogeographic studies in China have focused on the importance of genetic divergence and where should the shelter be located. Little attention has been paid to range expansion and recolonization routes in this region. In this study, two cpDNA fragments (psbK‐psbI and trnL‐F), two pairs of nuclear gene sequences (ITS and ETS), and nine pairs of SSR molecular markers were used, combined with Bayesian Skyline Plot method, gene barrier analysis, and species distribution models to explore the phylogeographical pattern, potential expansion routes and population dynamic history of Pinellia ternata from 22 population. The results showed that phylogeograhical pattern and genetic structure for P. ternata are effected by environmental heterogeneity and climate fluctuation, and it can be divided into two groups (Southwest group, Central and Eastern group) and thus there are at least two glacial refugia in China. Three expanding routes within groups were explored to contribute to the phylogeogrephic pattern of P. ternata based on the geographical distribution and network analysis of haplotypes. In a word, our study reveals repeated range expansions and inter/postglacial recolonization routes on the fragmented distribution pattern in China and resolves the refugia distributing in China and has also certain reference value for the protection of the medicinal plant P. ternata. [ABSTRACT FROM AUTHOR]

Many cooperatively breeding species live in groups with complex structure—large group sizes, low and variable kin structure, and multiple breeding pairs. Since these mixed‐kin groups typically form because of immigration of unrelated individuals of both sexes in addition to limited offspring dispersal, differences in patterns of dispersal can generate variation in group structure, even within the same species or population. Here, we examine how environmentally mediated dispersal patterns influence variation in group structure in the plural breeding superb starling (Lamprotornis superbus), an avian cooperative breeder that inhabits a spatiotemporally variable savanna environment and forms mixed‐kin groups with variable group sizes and more than one breeding pair per group. Using 4068 genome‐wide polymorphic loci and fine‐scale, remotely sensed ecological data from 22 groups sampled across a nearly 200 km2 environmental gradient in central Kenya, we find evidence of not only frequent and long‐distance dispersal in both sexes (low isolation‐by‐distance and weak genetic structure), but also directional dispersal from small groups in lower quality habitat with low normalised difference vegetation index (NDVI) to large groups in higher quality habitat with high NDVI. Additionally, we find stronger genetic structure among groups in lower quality habitat, and higher genetic diversity and lower relatedness of groups in higher quality habitat. Previous work using long‐term data from groups in the same population has shown that groups with lower relatedness are larger and have more breeding pairs. Long‐distance, directional dispersal to maximise individual fitness can thus lead to smaller and simpler kin‐based social groups in lower quality habitat, but larger and more complex mixed‐kin groups in higher quality habitat. Such intraspecific, within‐population variation in group structure, including variation in kin structure of social groups, could have profound implications for the relative importance of the evolutionary mechanisms (i.e. direct vs. indirect fitness benefits) underlying the formation of cooperative societies. [ABSTRACT FROM AUTHOR]

This study combined population genetics and parentage analysis to obtain foundational data for the conservation of Magnolia kwangsiensis. M. kwangsiensis is a Class I tree species that occurs in two disjunct regions in a biodiversity hotspot in southwest China. We assessed the genetic diversity and structure of this species across its distribution range to support its conservation management. Genetic diversity and population structure of 529 individuals sampled from 14 populations were investigated using seven nuclear simple sequence repeat (nSSR) markers and three chloroplast DNA (cpDNA) fragments. Parentage analysis was used to evaluate the pollen and seed dispersal distances. The nSSR marker analysis revealed a high genetic diversity in M. kwangsiensis, with an average observed (Ho) and expected heterozygosities (He) of 0.726 and 0.687, respectively. The mean and maximum pollen and seed dispersal distances were 66.4 and 95.7 m and 535.4 and 553.8 m, respectively. Our data revealed two distinct genetic groups, consistent with the disjunct geographical distribution of the M. kwangsiensis populations. Both pollen and seed dispersal movements help maintain genetic connectivity among M. kwangsiensis populations, contributing to high levels of genetic diversity. Both genetically differentiated groups corresponding to the two disjunct regions should be recognized as separate conservation units. [ABSTRACT FROM AUTHOR]

Desertification is a major threat to biodiversity in arid areas of the world, partly because many organisms in these regions already exist at or near the limits of their movement and physiology. Here, we used molecular data to investigate patterns of persistence and dispersal in an ecologically and economically important carpenter bee (Xylocopa grisescens Lepeletier) found throughout the semiarid Caatinga region of Brazil. We used a genome‐wide approach (double digest restriction‐site associated DNA, ddRAD) to gather genetic data from bees sampled from eight sites within a semiarid region subject to desertification in Northeastern Brazil. Across all populations, we observed a consistent heterozygosity and effective population size deficit along with low genetic differentiation. We did not find strong evidence of dispersal limitations caused by desertification in this study system despite data collection from sites up to 300 km distant. Thus, our data suggest that human‐mediated changes in the Caatinga, such as habitat loss, have impacted the population genetic patterns of X. grisescens. However, these impacts have also been softened by the species' biological characteristics, such as its relatively high capacity for movement. This study provides insights into how habitat changes might impact the long‐term survival of large solitary bees. [ABSTRACT FROM AUTHOR]

Summary: Scots pine is the foundation species of diverse forested ecosystems across Eurasia and displays remarkable ecological breadth, occurring in environments ranging from temperate rainforests to arid tundra margins. Such expansive distributions can be favored by various demographic and adaptive processes and the interactions between them.To understand the impact of neutral and selective forces on genetic structure in Scots pine, we conducted range‐wide population genetic analyses on 2321 trees from 202 populations using genotyping‐by‐sequencing, reconstructed the recent demography of the species and examined signals of genetic adaptation.We found a high and uniform genetic diversity across the entire range (global FST 0.048), no increased genetic load in expanding populations and minor impact of the last glacial maximum on historical population sizes. Genetic‐environmental associations identified only a handful of single‐nucleotide polymorphisms significantly linked to environmental gradients.The results suggest that extensive gene flow is predominantly responsible for the observed genetic patterns in Scots pine. The apparent missing signal of genetic adaptation is likely attributed to the intricate genetic architecture controlling adaptation to multi‐dimensional environments. The panmixia metapopulation of Scots pine offers a good study system for further exploration into how genetic adaptation and plasticity evolve under gene flow and changing environment. See also the Commentary on this article by Duffy, 243: 830–832. [ABSTRACT FROM AUTHOR]

The population of common cuttlefish Sepia officinalis in the English Channel recently developed two life cycles: annual (spawning 1 y.o.) and biennial (spawning 2 y.o.) instead of the biennial strategy known before, associated with increasing environmental temperatures in recent decades because of climate changes. Both groups differ in the size of mature animals (110–196 mm mantle length vs. 140–262 mm) and the number of chambers in the cuttlebone (60–97 in annual vs. 93–152 in biennial). The annual group represented some 15%–20% of the population, and the proportion of early spawners increased during the reproductive period, from 3%–5% in February/March to 50%–70% in June/July. Among spawning cuttlefish males predominated as ~2:1. Such environmentally driven changes in historical ecology as exemplified by the cuttlefish might be a critical link in the adaptation of the cephalopod life cycles to changing ecosystems. [ABSTRACT FROM AUTHOR]

Many studies suggest that aside from environmental variables, such as topography and climate, species‐specific ecological traits are relevant to explain the geographic distribution of intraspecific genetic lineages. Here, we investigated whether and to what extent incorporating such traits systematically improves the accuracy of random forest models in predicting genetic differentiation among pairs of localities. We leveraged available ecological datasets for birds and tested the inclusion of two categories of ecological traits: dispersal‐related traits (i.e. morphology and foraging ecology) and demographic traits (such as species survival rate and generation length). We estimated genetic differentiation from published mitochondrial DNA sequences for 28 species of birds (1578 total genetic samples, 391 localities) in the Atlantic Forest of South America. Aside from the aforementioned ecological traits, we included geographic, topographic and climatic distances between localities as environmental predictors. We then created models using all available data to evaluate model uncertainty both across space and across the different categories of predictors. Finally, we investigated model uncertainty in predicting genetic differentiation individually for each species (a common challenge in conservation biology). Our results show that while environmental conditions are the most important predictors of genetic differentiation, model accuracy largely increases with the addition of ecological traits. Additionally, the inclusion of dispersal traits improves model accuracy to a larger extent than the inclusion of demographic traits. Similar results are observed in models for individual species, although model accuracy is highly variable. We conclude that ecological traits improve predictive models of genetic differentiation, refining our ability to predict phylogeographic patterns from existing data. Additionally, demographic traits may not be as informative as previously hypothesized. Finally, prediction of genetic differentiation for species with conservation concerns may require further careful assessment of the environmental and ecological variation within the species range. [ABSTRACT FROM AUTHOR]

Examining patterns of genetic diversity are crucial for conservation planning on endangered species, while inferring the underlying process of recent anthropogenic habitat modifications in the context potential long‐term demographic changes remains challenging. The globally endangered scaly‐sided merganser (SSME), Mergus squamatus, is endemic to a narrow range in Northeast Asia, and its population has recently been contracted into two main breeding areas. Although low genetic diversity has been suggested in the Russian population, the genetic status and demographic history of these individuals have not been fully elucidated. We therefore examined the genetic diversity and structure of the breeding populations of the SSME and investigated the relative importance of historical and recent demographic changes to the present‐day pattern of genetic diversity. Using 10 nuclear microsatellite (SSR) markers and mitochondrial DNA (mtDNA) control region sequences, we found limited female‐inherited genetic diversity and a high level of nuclear genetic diversity. In addition, analysis of both markers consistently revealed significant but weak divergence between the breeding populations. Inconsistent demographic history parameters calculated from mtDNA and bottleneck analysis results based on SSR suggested a stable historical effective population size. By applying approximate Bayesian computation, it was estimated that populations started to genetically diverge from each other due to recent fragmentation events caused by anthropogenic effects rather than isolation during Last Glacial Maximum (LGM) and post‐LGM recolonization. These results suggest that limited historical population size and shallow evolutionary history may be potential factors contributing to the contemporary genetic diversity pattern of breeding SSME populations. Conservation efforts should focus on protecting the current breeding habitats from further destruction, with priority given to both the Russian and Chinese population, as well as restoring the connected suitable breeding grounds. [ABSTRACT FROM AUTHOR]

Aim: Our aim was to assess the population structure, genetic diversity and demographic history of the wolverine (Gulo gulo) throughout its entire Eurasian range. Additionally, we aimed to contextualize and put into perspective the state of the endangered Fennoscandian population by emphasizing its connectivity to other populations. Location: The main study area covered most of the Eurasian wolverine range, with samples from Finland, Russia, Kazakhstan and Mongolia. Methods: Using a 495 bp fragment of the mitochondrial DNA control region and a frequently used set of 14 microsatellite markers on an extensive dataset of samples, we assessed the population structure, genetic diversity, and demographic history of wolverines with a variety of population genetic analyses. Results: According to both nuclear and mitochondrial genetic markers, Eurasian wolverines exhibit substructure, with the most distinct population located in Fennoscandia. The Fennoscandian population has undergone a genetic bottleneck, likely influencing its genetic diversity, which is notably the lowest in Eurasia. Genetic diversity in the rest of Eurasia gradually rises towards the central part of the range and decreases again in the east, although not as significantly as in the west. Main Conclusions: This study reveals the population structure of wolverines across Eurasia and provides direction for allocating conservation efforts to sustain a diverse and connected wolverine population. While most of the Eurasian populations seem to be well‐connected and genetically diverse, the Fennoscandian wolverines may need better connectivity to the other Eurasian populations to ensure gene flow and long‐term persistence. Our study further highlights the importance of considering the population genetic structure and diversity of the entire species range when planning management strategies. [ABSTRACT FROM AUTHOR]

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Fusarium circinatum is an important fungal pathogen of Pinus species utilized in commercial forestry worldwide. In Colombia, it was first found on nursery plants and later in plantations associated with basal cankers on young trees. In this study, we explored the population diversity of the pathogen in Colombia by analyzing 136 isolates collected from diseased nursery plants (2005–2007) and plantation trees (2017 and 2020). These were sourced from different geographical regions and Pinus species. Genotyping was performed using 10 microsatellite markers, while mating types were identified with PCRs targeting the MAT1 locus. Using microsatellites, a total of 33 multilocus haplotypes were detected. Genetic diversity indices showed low levels of diversity in both the overall collection and in specific collection groupings. The data also suggested that a small number of isolates had unique origins in the country (p <.05), and relatively low levels of population differentiation were detected between the nursery and plantation collections. All the isolates were scored as having the MAT1‐1 mating type, and no evidence for the random association among microsatellite alleles (p =.0001) was found. Overall, these data suggest that F. circinatum was introduced into Colombia a small number of times, likely on seed for nursery production. Furthermore, the data also indicate that the pathogen has spread from nurseries to the plantations via asexual reproduction and on asymptomatic plants. This has resulted in a highly clonal F. circinatum population in Colombia that has resulted from accidental introductions of the pathogen into a production nursery. [ABSTRACT FROM AUTHOR]

Summary: Alfalfa (Medicago sativa L.) is one of the most important forage legumes in the world, including autotetraploid (M. sativa ssp. sativa) and diploid alfalfa (M. sativa ssp. caerulea, progenitor of autotetraploid alfalfa). Here, we reported a high‐quality genome of ZW0012 (diploid alfalfa, 769 Mb, contig N50 = 5.5 Mb), which was grouped into the Northern group in population structure analysis, suggesting that our genome assembly filled a major gap among the members of M. sativa complex. During polyploidization, large phenotypic differences occurred between diploids and tetraploids, and the genetic information underlying its massive phenotypic variations remains largely unexplored. Extensive structural variations (SVs) were identified between ZW0012 and XinJiangDaYe (an autotetraploid alfalfa with released genome). We identified 71 ZW0012‐specific PAV genes and 1296 XinJiangDaYe‐specific PAV genes, mainly involved in defence response, cell growth, and photosynthesis. We have verified the positive roles of MsNCR1 (a XinJiangDaYe‐specific PAV gene) in nodulation using an Agrobacterium rhizobia‐mediated transgenic method. We also demonstrated that MsSKIP23_1 and MsFBL23_1 (two XinJiangDaYe‐specific PAV genes) regulated leaf size by transient overexpression and virus‐induced gene silencing analysis. Our study provides a high‐quality reference genome of an important diploid alfalfa germplasm and a valuable resource of variation landscape between diploid and autotetraploid, which will facilitate the functional gene discovery and molecular‐based breeding for the cultivars in the future. [ABSTRACT FROM AUTHOR]

Management of thorny skate (Amblyraja radiata) in the Northwest Atlantic has posed a conservation dilemma for several decades due to the species' lack of response to strong conservation efforts in the US Gulf of Maine and the Canadian Scotian Shelf, confusion over the relationship between two reproductive size morphs of differing life histories that are sympatric in the Northwest Atlantic, and conflicting data on regional population connectivity throughout the species' broader range. To better assess potential A. radiata regional population differentiation and genetic links to life‐history variation, we analysed complete mitochondrial genome sequences from 527 specimens collected across the species' North Atlantic geographic range, with particular emphasis on the Northwest Atlantic region. A high level of genetic diversity was evident across the North Atlantic, but significant genetic differentiation was identified between specimens inhabiting the Northwest (Gulf of Maine and Newfoundland) and Northeast (Greenland, Iceland, North Sea, and Arctic Circle) Atlantic. In the Northwest Atlantic, significant differentiation between the Gulf of Maine and Newfoundland regions was revealed; however, the overall level of differentiation was very low. No genetic difference was identified between the large and small reproductive morphs. The results of this study advance our understanding of A. radiata population structure in the North Atlantic but do not resolve all the questions confounding our understanding of the species' biology and evolutionary history. [ABSTRACT FROM AUTHOR]

Chronic wasting disease (CWD) can spread among cervids by direct and indirect transmission, the former being more likely in emerging areas. Identifying subpopulations allows the delineation of focal areas to target for intervention. We aimed to assess the population structure of white‐tailed deer (Odocoileus virginianus) in the northeastern United States at a regional scale to inform managers regarding gene flow throughout the region. We genotyped 10 microsatellites in 5701 wild deer samples from Maryland, New York, Ohio, Pennsylvania, and Virginia. We evaluated the distribution of genetic variability through spatial principal component analysis and inferred genetic structure using non‐spatial and spatial Bayesian clustering algorithms (BCAs). We simulated populations representing each inferred wild cluster, wild deer in each state and each physiographic province, total wild population, and a captive population. We conducted genetic assignment tests using these potential sources, calculating the probability of samples being correctly assigned to their origin. Non‐spatial BCA identified two clusters across the region, while spatial BCA suggested a maximum of nine clusters. Assignment tests correctly placed deer into captive or wild origin in most cases (94%), as previously reported, but performance varied when assigning wild deer to more specific origins. Assignments to clusters inferred via non‐spatial BCA performed well, but efficiency was greatly reduced when assigning samples to clusters inferred via spatial BCA. Differences between spatial BCA clusters are not strong enough to make assignment tests a reliable method for inferring the geographic origin of deer using 10 microsatellites. However, the genetic distinction between clusters may indicate natural and anthropogenic barriers of interest for management. [ABSTRACT FROM AUTHOR]

Knowledge of functional dispersal barriers in the marine environment can be used to inform a wide variety of management actions, such as marine spatial planning, restoration efforts, fisheries regulations, and invasive species management. Locations and causes of dispersal barriers can be studied through various methods, including movement tracking, biophysical modeling, demographic models, and genetics. Combining methods illustrating potential dispersal, such as biophysical modeling, with realized dispersal through, e.g., genetic connectivity estimates, provides particularly useful information for teasing apart potential causes of observed barriers. In this study, we focus on blue mussels (Mytilus edulis) in the Skagerrak—a marginal sea connected to the North Sea in Northern Europe—and combine biophysical models of larval dispersal with genomic data to infer locations and causes of dispersal barriers in the area. Results from both methods agree; patterns of ocean currents are a major structuring factor in the area. We find a complex pattern of source‐sink dynamics with several dispersal barriers and show that some areas can be isolated despite an overall high dispersal capability. Finally, we translate our finding into management advice that can be used to sustainably manage this ecologically and economically important species in the future. [ABSTRACT FROM AUTHOR]

Scots pine (Pinus sylvestris L.) is one of the most important tree species of the temperate and boreal zones in Eurasia. Its wide distribution range and current patterns of genetic variation have been influenced by Quaternary climatic oscillations and the demographic processes connected to them. In order to better understand the relationship between evolutionary history and demographic factors in a widespread species with a large genome, we used the single‐nucleotide polymorphism (SNP) array to genotype thousands of SNP markers across 62 natural populations (N = 686 trees) of Scots pine in Eurasia. This provides the largest range‐wide SNPs' genetic diversity assessment of Scots pine to date. Our findings show evidence of past admixture events between genetic clusters that were retained despite the potential for effective pollen‐mediated gene flow across the species' distribution range. We also examined the contemporary population structure of the species and analyzed the range‐wide genetic diversity patterns. Phylogenetic analyses and demographic modeling suggest that the observed divergence patterns between genetic lineages likely predate the last glaciation events. Two of the most distinctive groups are represented by trees from the eastern parts of Fennoscandia and Eastern Russia, which have remained separated since the mid‐Pleistocene. The patterns of genetic variation also confirm the dual colonization of Fennoscandia and the existence of an admixture zone in Central Europe that was formed during multiple waves of postglacial recolonization. This study provides insights into the genetic relationships of Scots pine populations from Europe and Asia and offers a more comprehensive understanding of the species' history. Highlights: •A range‐wide population genomic study of important highly outcrossing and wind‐dispersed Eurasian conifer (Pinus sylvestris) was carried out.•The signature of distinct genetic lineages was maintained across populations despite putative efficient gene flow.•Patterns of spatial genetic variation were shaped long before the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

California, USA, is home to 3 subspecies of North American elk (Cervus canadensis): Roosevelt (C. c. roosevelti), Rocky Mountain (C. c. nelsoni), and tule (C. c. nannodes). Effective management requires a baseline understanding of each subspecies' range, admixture zones, and geographic patterns of genetic diversity. To address these questions, we genotyped 1,271 individual elk from California (n = 1,204) and reference populations of Rocky Mountain and Roosevelt elk from Nevada (n = 32) and Oregon (n = 35), USA. Using 19 polymorphic microsatellite loci, we detected admixture between Roosevelt and Rocky Mountain elk at a contact zone in northern California, and between Roosevelt and tule elk in north-coastal California and centralcoastal California. We identified a genetically distinct population of Roosevelt elk in northwestern California, likely reflecting the remnant population that survived a large demographic decline from overhunting during the 1800s. Tule elk exhibited lower levels of heterozygosity (0.44 ± 0.03 [SD]) and allelic richness (2.9±0.2) than Rocky Mountain (0.58±0.05, 4.9±0.4, respectively) and Roosevelt (0.50 ± 0.06, 4.4 ± 0.6, respectively) elk. Among tule elk populations, heterozygosity varied, with the lowest heterozygosity (0.23 ± 0.05) corresponding to the oldest enclosed herd used over the past century as a source of translocations. Among tule elk populations, genetic structure revealed several cases of successful and unsuccessful reintroduction or augmentation attempts. Results provide an essential baseline for future monitoring and decisions about harvest management, translocations to preserve genetic diversity, and landscape-level conservation planning to maintain, enhance, or obstruct connectivity of elk populations. Genome-wide sequencing and analyses are needed to quantify inbreeding absolutely and assess genetic load and the age of admixture where subspecies currently exchange genes. [ABSTRACT FROM AUTHOR]

The Asian monsoon scallop, Amusium pleuronectes, is a key member of the most commercially harvested shellfish community in Asia. Patterns of genetic diversity and natural population structure in the target species were investigated to gain a better understanding of its evolutionary history. Samples were collected from five sites across the Indonesian Archipelago. We characterized sequence variation in an mtDNA control region fragment in 249 individuals. The genetic diversity (h = ranging from 0.83 to 0.92) and nucleotide diversity (π = ranging from 0.24 to 0.32) were low compared to the estimates reported for many other similar shellfish taxa. Nonetheless, analysis of molecular variance revealed significant genetic differentiation, FST = 0.0203 (p <.005 after Bonferroni corrections). Furthermore, both Pairwise fixation index values showed significance among majority population sites, indicating that dispersal potential and gene flow were low in the past. This pattern likely reflects a low dispersal potential, potentially allowing local adaptation to sites that augment any oceanographic and geographic contribution to genetic structure. The results described herein provide a foundation for developing better conservation strategies for the target species in the future. [ABSTRACT FROM AUTHOR]

Understanding the processes that underlie the development of population genetic structure is central to the study of evolution. Patterns of genetic structure, in turn, can reveal signatures of isolation by distance (IBD), barriers to gene flow, or even the genesis of speciation. However, it is unclear how severe range restriction might impact the processes that dominate the development of genetic structure. In narrow endemic species, is population structure likely to be adaptive in nature, or rather the result of genetic drift? In this study, we investigated patterns of genetic diversity and structure in the narrow endemic Hayden's ringlet butterfly. Specifically, we asked to what degree genetic structure in the Hayden's ringlet can be explained by IBD, isolation by resistance (IBR) (in the form of geographic or ecological barriers to migration between populations), and isolation by environment (in the form of differences in host plant availability and preference). We employed a genotyping‐by‐sequencing (GBS) approach coupled with host preference assays, Bayesian modelling, and population genomic analyses to answer these questions. Our results suggest that despite their restricted range, levels of genetic diversity in the Hayden's ringlet are comparable to those seen in more widespread butterfly species. Hayden's ringlets showed a strong preference for feeding on grasses relative to sedges, but neither larval preference nor potential host availability at sampling sites correlated with genetic structure. We conclude that geography, in the form of IBR and simple IBD, was the major driver of contemporary patterns of differentiation in this narrow endemic species. [ABSTRACT FROM AUTHOR]

Botrytis cinerea is considered to be the second most destructive fungal pathogen worldwide, causing severe pre‐ and postharvest losses in cut roses. However, to date, no systematic research on its characteristics in cut roses has been reported. In our study, a total of 100 isolates from cut roses from Yunnan, China, were analysed. A combination of morphological characteristics and phylogenetic analysis of RPB2 revealed that 100 isolates were of the species B. cinerea. These isolates were pathogenic on unwounded detached rose petals. Pathogenicity was evaluated according to the size of petal spots and categorized into grades 0–5, from weak to strong. The inhibition rate varied greatly following the addition of procymidone (21.9%–100%) and cyprodinil (25.0%–92.3%). Analysis of Bc‐hch sequences revealed all isolates belong to phylogenetic Group II. According to the presence or absence of transposable elements, 87, 5, 4 and 4 isolates were identified as transposa, vacuma, Boty‐only and Flipper‐only types, respectively. Detection of mating type indicated that all isolates were heterothallic with 45% belonging to MAT1‐1 and 55% to MAT1‐2. Isolates were divided into four subpopulations when analysing single‐nucleotide polymorphisms at the genomic level, with a significant difference in pathogenicity between subpopulations 1 and 4. The evolutionary tree indicated that isolates AN‐02, AN‐22 and SM‐C18 were clustered in the root, suggesting an earlier evolutionary time than other isolates; moreover, they all exhibited low pathogenicity (grade 1). This systematic study of the characteristics of B. cinerea will provide significant support for grey mould control and further research. [ABSTRACT FROM AUTHOR]

Ecological demands, such as sex and environmental conditions, determine species' behaviour, such as dispersal, and shape local population structures. However, only marginal knowledge of these factors exists for afro‐tropical insects so far.Therefore, we performed a mark–release–recapture study in the coastal region of Kenya over a period of 2 months, covering the dry and the rainy seasons. As study species, we used four co‐occurring but ecologically diverging butterfly species, the forest species Bicyclus safitza and Junonia natalica and the savannah species Junonia oenone and Byblia ilithyia. The study area represents an ecosystem mosaic consisting of anthropogenic habitats as well as natural forest and savannah, assessed by detailed landscape mapping.We obtained 1701 capture events, comprising 1224 individuals with an overall recapture rate of 24% (ranging from 15% to 48%). The analyses based on these results allowed an assessment of the population ecology, dispersal behaviour and habitat preferences of these species.Demographic models inferred different patterns of population dynamics among species. All species preferred the habitats they were known for. The observed dispersal distances were rather low ranging from a mean of 25 to 72 m, referring to taxa and sexes. The dispersal extrapolations were unreliably low for the negative exponential function, while the values for inverse power function were credible. The latter predicted a considerably higher long‐distance dispersal capacity in males than in females of the forest species B. safitza and J. natalica, while females dispersed more than males in the savannah species J. oenone and B. ilithyia.Our results obtained from these four ecologically diverging afro‐tropical butterfly species underline that species' behaviour, such as dispersal, is strongly determined by habitat preferences, sex and the availability of resources. [ABSTRACT FROM AUTHOR]

Genetic diversity is a key component of evolution, and unraveling factors that promote genetic differentiation in space and time is a central question in evolutionary biology. One of the most diverse and ecologically important tree genera in tropical forests worldwide is Ficus (Moraceae). It has been suggested that, given the great dispersal capacity of pollinating fig wasps (Chalcidoidea; Agaonidae), the spatial genetic structure, particularly in monoecious fig species, should be weak. However, no studies have addressed the factors that determine the genetic structure of Ficus species in regions of high geological, geographic, and climatic complexity, such as the Mexican Transition Zone. Using nuclear single nucleotide polymorphisms (5311 SNPs) derived from low‐coverage whole genomes and 17 populations, we analyzed the population genomics of Ficus pringlei to characterize neutral and adaptive genetic variation and structure and its association with geographic barriers such as the Trans‐Mexican Volcanic Belt, environmental heterogeneity, and wind connectivity. From genomic data of 71 individuals, high genetic diversity, and the identification of three genomic lineages were recorded (North, South, and Churumuco). The results suggest that genetic variation is primarily determined by climatic heterogeneity. Ficus pringlei populations from the north and south of the Trans‐Mexican Volcanic Belt also exhibited minimal genetic differentiation (FST = 0.021), indicating that this mountain range may not act as an insurmountable barrier to gene flow. Wind connectivity is also highlighted in structuring putative adaptive genetic variation, underscoring the intricate complexity of the various factors influencing genetic variation in the species. This study provides information on the possible mechanisms underlying the genetic variation of endemic species of the tropical dry forest of Western Mexico, such as F. pringlei. [ABSTRACT FROM AUTHOR]

Genetics is a fast‐moving field, and for conservation practitioners or ecologists, it can be bewildering. The choice of marker used in studies is fundamental; in the literature, preference has recently shifted from microsatellites to single nucleotide polymorphism (SNP) loci. Understanding how marker type affects estimates of population genetic parameters is important in the context of conservation, especially because the accuracy of estimates has a bearing on the actions taken to protect threatened species. We compare parameter estimates between seven microsatellites, 3761 SNP loci, and a random subset of 100 SNPs for the exact same 324 individual swift parrots, Lathamus discolor, and also use 457 additional samples from subsequent years to compare SNP estimates. Both marker types estimated a lower HO than HE. We show that microsatellites and SNPs mainly indicate a lack of spatial genetic structure, except when a priori collection locations were used on the SNP data in a discriminant analysis of principal components (DAPC). The 100‐SNP subset gave comparable results to when the full dataset was used. Estimates of effective population size (Ne) were comparable between markers when the same individuals were considered, but SNPs had narrower confidence intervals. This is reassuring because conservation assessments that rely on population genetic estimates based on a few microsatellites are unlikely to be nullified by the general shift toward SNPs in the literature. However, estimates between markers and datasets varied considerably when only adult samples were considered; hence, including samples of all age groups is recommended to be used when available. The estimated Ne was higher for the full SNP dataset (2010–2019) than the smaller comparison data (2010–2015), which might be a better reflection of the species status. The lower precision of microsatellites may not necessarily be a barrier for most conservation applications; however, SNPs will improve confidence limits, which may be useful for practitioners. [ABSTRACT FROM AUTHOR]

Understanding fish movement is critical in determining the spatial scales in which to appropriately manage wild populations. Genetic markers provide a natural tagging approach to assess the degree of gene flow and population connectivity across a species distribution. We investigated the genetic structure of black bream Acanthopagrus butcheri across its entire distribution range in Australia, as well as regional scale gene flow across south‐eastern Australia by undertaking a comprehensive analysis of the populations in estuaries across the region. We applied genome‐wide sampling of single‐nucleotide polymorphism (SNP) markers generated from restriction site‐associated DNA sequencing. Genetic structure and potential gene flow was assessed using principal component analyses and admixture analyses (STRUCTURE). Using 33,493 SNPs, we detected broad scale genetic structuring, with limited gene flow among regional clusters (i.e. Western Australia, South Australia and western Victoria; and eastern Victoria, Tasmania and New South Wales). This is likely the result of unsuitable habitats, strong ocean currents (e.g. the Leeuwin Current and the East Australian Current), large water bodies (e.g. Bass Strait) and known biogeographical provinces across the continent. Local‐scale genetic structuring was also identified across the south‐eastern Australian estuaries sampled, reflecting that the coexistence of both migratory and resident individuals within populations (i.e. partial migration), and the movement of fish into coastal waters, still results in strong philopatry across the region. Instances of movement among estuaries at this spatial scale were primarily found between adjacent estuaries and were likely attributed to lone migrants utilising inshore coastal currents for movement beyond nearby habitats. Targeting SNP markers in A. butcheri at this continental scale highlighted how neither spatial proximity of estuaries nor black bream's ability to move into coastal waters reflects increased gene flow. Overall, our findings highlight the importance of location‐specific management. [ABSTRACT FROM AUTHOR]

Life table response experiments (LTREs) decompose differences in population growth rate between environments into separate contributions from each underlying demographic rate. However, most LTRE analyses make the unrealistic assumption that the relationships between demographic rates and environmental drivers are linear and independent, which may result in diminished accuracy when these assumptions are violated. We extend regression LTREs to incorporate nonlinear (second‐order) terms and compare the accuracy of both approaches for three previously published demographic datasets. We show that the second‐order approach equals or outperforms the linear approach for all three case studies, even when all of the underlying vital rate functions are linear. Nonlinear vital rate responses to driver changes contributed most to population growth rate responses, but life history changes also made substantial contributions. Our results suggest that moving from linear to second‐order LTRE analyses could improve our understanding of population responses to changing environments. [ABSTRACT FROM AUTHOR]

Mesodesma donacium is a surf clam endemic to the southeast Pacific coast, and it is an important resource species of the sandy beach artisanal fishery in Peru and Chile. Over time, the species has shown high variability in population dynamics (presence and abundance), which has been attributed to overfishing and environmental events. In this study, we assess the phylogeography of seven natural beds of M. donacium (17 to 42° S), to reveal the geographic distribution of the genetic diversity through the analysis of 278 sequences of the mitochondrial gene COI. Sequences of the nuclear genes 18S and 28S were used to evaluate the divergence of COI haplogroups. Two divergent parapatric mitochondrial haplogroups were found, which lacked divergence at nuclear markers (18S and 28S); this mito‐nuclear discordance allows inferring that there is no reproductive isolation of mitochondrial haplogroups. The North haplogroup is the only one present at the northernmost site, while only the South haplogroup was present in Cucao in the south. Between 28° and 32° S, coincident with a coastal biogeographic break at 30° S, both haplogroups are in sympatry. Haplogroups differed in their genetic structure, with the North haplogroup representing a single, highly diverse population and the South haplogroup with genetic differentiation and more restricted genetic diversity and gene flow. The divergence in mitochondrial haplogroups without nuclear divergence suggests a past scenario of geographic isolation in the northern and southern areas, without developing reproductive isolation, followed by secondary contact. Given the phylogeography, genetic information should be considered in restocking and management activities. [ABSTRACT FROM AUTHOR]

The conservation and sustainable utilization of cattle genetic resources necessitate a comprehensive understanding of their genetic diversity and population structure. This study provides an analysis of five native Turkish cattle breeds: Anatolian Black (ANB), Turkish Grey (TUR), Anatolian Southern Yellow (ASY), East Anatolian Red (EAR), and South Anatolian Red (SAN) using 50 K SNP data. These breeds were compared with three European breeds, Simmental (SIM), Holstein (HOL), and Jersey (JER), and three Asian Zebu breeds: Arabic Zebu (ZAR), Nelore (NEL), and Red Sindhi (RSI). Genetic diversity indices demonstrated moderate heterogeneity among the breeds, with TUR exhibiting the highest observed heterozygosity (Ho = 0.35). Wright's Fst values indicated significant genetic differentiation, particularly between Turkish breeds and both European (Fst = 0.035–0.071) and Asian breeds (Fst = 0.025–0.150). Principal component analysis distinguished the unique genetic profiles of each breed cluster. Admixture analysis revealed degrees of shared genetic ancestry, suggesting historical gene flow between Turkish, European, and Asian breeds. Analysis of molecular variance (AMOVA) attributed approximately 58% of the variation to population differences. Nei's genetic distances highlighted the closer genetic relatedness within Turkish breeds (distance ranges between 0.032 and 0.046) and suggested a more relative affinity of TUR with European breeds. The study's phylogenetic assessments elucidate the nuanced genetic relationships among these breeds, with runs of homozygosity (ROH) analysis indicating patterns of ancestral relatedness and moderate levels of inbreeding, particularly evident in Turkish breeds. Our findings provide valuable insights into the genetic landscape of Turkish cattle, offering a crucial foundation for informed conservation and breeding strategies aimed at preserving these breeds' genetic integrity and heritage. [ABSTRACT FROM AUTHOR]

Habitat fragmentation can increase the chance of population bottlenecks and inbreeding, and may ultimately lead to reduced fitness and local extinction. Notelaea lloydii is a native olive species endemic to Australia and listed as vulnerable due to its restricted distribution. A recent molecular systematics study has revealed there might be some geographic structuring among N. lloydii populations. Therefore, we undertook a genome‐wide single nucleotide polymorphism (SNP) analysis to determine levels and patterns of genetic diversity, inbreeding and gene flow within and among N. lloydii populations in south‐eastern Queensland. Furthermore, as the reproductive phase of a plant's life history has a profound influence on genetic diversity, life history reproductive traits were also studied. Our SNP analysis revealed low genetic diversity, inbreeding and significant genetic structuring even among proximate populations. Results of a flower and fruit bagging experiment in two consecutive seasons revealed that N. lloydii produced many flowers but only a few fruits survived to maturity. There were no differences in bagged and un‐bagged flowering and fruiting rates, and therefore, we conclude that the high fruit abortion rate was probably due to inbreeding depression and/or suboptimal conditions, rather than pollinator availability and insect attack. Overall, results of this study indicate that the populations of N. lloydii are small, inbred and genetically isolated and represent unique management units that require local conservation management due to ongoing threats associated with urbanisation. [ABSTRACT FROM AUTHOR]

The life history of insular gecarcinid crabs is divided into a marine larval and an adult phase, adapted to the terrestrial environment. As adults, individuals migrate seasonally to locations near the sea, engaging in reproductive behaviors. Therefore, identifying breeding and recruitment areas is crucial for the conservation of insular gecarcinids, especially for those endangered, such as Johngarthia lagostoma (H. Milne Edwards, 1837). We used sex ratio and sexual dimorphism analyses (body and cheliped size) as well as records of juveniles and adults to describe the population structure of J. lagostoma in the Trindade Island, Brazil. During the reproductive period, several population parameters were compared among sites with different altitudes, comprising two beaches (Andradas and Tartarugas) and two hills (Príncipe, 136 m; and Desejado, 612 m). Overall, males predominated in the population and invested more in body and cheliped growth than females. However, at Andradas Beach, it was observed a similar frequency of adult males and females as well as a small difference in the body size between the sexes. In comparison, the smallest crabs were found at Príncipe Hill. The analyzed population presented a predominance of adults, especially at Andradas Beach (93.1%). Compared to the other sites sampled, Príncipe Hill showed the highest abundance of juveniles (males: 22.2%; females: 40.8%). Thus, Andradas Beach was considered a reproductive site, while Príncipe Hill had the highest density of juveniles, which makes them priority areas for the conservation of J. lagostoma in Trindade Island. [ABSTRACT FROM AUTHOR]

Urbanization is a persistent and widespread driver of global environmental change, potentially shaping evolutionary processes due to genetic drift and reduced gene flow in cities induced by habitat fragmentation and small population sizes. We tested this prediction for the eastern grey squirrel (Sciurus carolinensis), a common and conspicuous forest‐dwelling rodent, by obtaining 44K SNPs using reduced representation sequencing (ddRAD) for 403 individuals sampled across the species' native range in eastern North America. We observed moderate levels of genetic diversity, low levels of inbreeding, and only a modest signal of isolation‐by‐distance. Clustering and migration analyses show that estimated levels of migration and genetic connectivity were higher than expected across cities and forested areas, specifically within the eastern portion of the species' range dominated by urbanization, and genetic connectivity was less than expected within the western range where the landscape is fragmented by agriculture. Landscape genetic methods revealed greater gene flow among individual squirrels in forested regions, which likely provide abundant food and shelter for squirrels. Although gene flow appears to be higher in areas with more tree cover, only slight discontinuities in gene flow suggest eastern grey squirrels have maintained connected populations across urban areas in all but the most heavily fragmented agricultural landscapes. Our results suggest urbanization shapes biological evolution in wildlife species depending strongly on the composition and habitability of the landscape matrix surrounding urban areas. [ABSTRACT FROM AUTHOR]

Exserohilum turcicum is the causative agent of northern leaf blight of maize and sorghum. Although host specificity of E. turcicum has been observed from isolates collected from maize and sorghum, limited molecular evidence has been presented so far for the formation of formae speciales. In this study, 15 simple‐sequence repeat (SSR) markers were used to study genetic diversity and population structure of 60 E. turcicum isolates from maize and sorghum in Henan province of China. A total of 54 haplotypes were identified from all isolates, in which 29 haplotypes were unique to the maize population and 25 were unique to the sorghum population. The phylogenetic tree showed that 60 isolates were clustered into two genetic groups; Group I consisted of 30 isolates from sorghum and Group II consisted of 30 isolates from maize. The formation of two groups was also supported by the result of principal component analysis. The analysis of population structure indicated that the main source of genetic compositions was completely different between the maize and sorghum populations. The fixation index (FST) and gene flow (Nm) between the two populations were 0.184 and 1.111, respectively. The analysis of molecular variance demonstrated that 27% and 73% of the total variation were distributed between and within the two populations, respectively. These findings reveal a high level of genetic divergence between E. turcicum populations associated with maize and sorghum and advance our understanding of the molecular basis underlying host specificity of E. turcicum. [ABSTRACT FROM AUTHOR]

Inle Lake is an ancient lake in Myanmar, which is an important area with unique and diverse fauna. Its ichthyofauna is believed to have formed non‐radiatively, but the historical processes are poorly understood. To elucidate the mechanisms that shape species diversity in this moderately isolated biogeographical 'island', this study focused on a typical endemic fish of Inle Lake, Channa harcourtbutleri (Channidae, Anabantiformes), with its widely distributed sister species, C. limbata, and estimated the historical distribution and diversification processes of the endemic fish based on genome‐wide polymorphism (MIG‐seq) and mitochondrial DNA data. Channa harcourtbutleri contained two genetically and morphologically distinct groups inhabiting Inle Lake and the surrounding rivers respectively. These two groups were genetically the closest to each other; however, the riverine group showed some similarity to the closely related species, C. limbata from Southeast Asia. The mtDNA haplotypes of the endemic species were not monophyletic; most of the riverine group had haplotypes identical or close to those of C. limbata from the upper Irrawaddy and Salween rivers. The time tree suggested that C. harcourtbutleri diverged from C. limbata in the early Pleistocene and then experienced secondary contact with C. limbata in the late Pleistocene. Genetic and morphological differentiation within C. harcourtbutleri suggests that local adaptation to different environments has played an important role for the coexistence of its two forms with some reproductive isolation. Further, the results highlight the importance of multiple colonization and allopatric speciation in shaping biodiversity in the long‐term, moderately isolated environments. [ABSTRACT FROM AUTHOR]