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A new invasive snapping shrimp from the Alpheus lobidens De Haan, 1849 species complex has become one of the most frequently observed crustaceans in certain saltmarshes along the southwestern Spanish coast. The first place in Europe where this invasion has occurred is reported in this study; however, little is known about this species, even within its undetermined native range. Here, the population structure, density, sex ratio, sexual dimorphism, reproductive period, and relative growth of this nonnative shrimp are reported for an intertidal saltmarsh in SW Spain based on monthly data collection over a year. Ovigerous females were collected during all months of the year. This population trait is not found in any native crustacean in the temperate zone of Europe. The sex ratio showed a similar proportion of male and female individuals, 0.88:1 (F:M), throughout the year. Sexual dimorphism was evident in the growth characteristics of body structures and implications are discussed. These results highlight the successful establishment of this shrimp in the Mediterranean climate area of Spain and have implications on marine fauna conservation and management. These findings also provide a basis for future comparative research in the shrimp native regions and enhance understanding of the species population dynamics. KEY WORDS: Alpheus lobidens, nonindigenous species, Caridea, life-history traits, size, reproduction, San Pedro River, snapping shrimp, INTRODUCTION The caridean family Alpheidae Rafinesque, 1815, is present in various marine habitats, spanning tropical, and temperate regions and can be found from the intertidal zone to deep waters (Anker [...]

• Automating wildlife monitoring with wireless 4G cameras and end-to-end data streams. • Remote monitoring of sensor performance, API handling and automated task management. • Deep learning for automated identification of focal species and human detection. • Total cost saving of >40 % through automation, AI and less regular site visits. • Enabling technologies allow scaling-up of a cost-efficient biodiversity monitoring. Modern approaches with advanced technology can automate and expand the extent and resolution of biodiversity monitoring. We present the development of an innovative system for automated wildlife monitoring in a coastal Natura 2000 nature reserve of the Netherlands with 65 wireless 4G wildlife cameras which are deployed autonomously in the field with 12 V/2A solar panels, i.e. without the need to replace batteries or manually retrieve SD cards. The cameras transmit images automatically (through a mobile network) to a sensor portal, which contains a PostgreSQL database and functionalities for automated task scheduling and data management, allowing scientists and site managers via a web interface to view images and remotely monitor sensor performance (e.g. number of uploaded files, battery status and SD card storage of cameras). The camera trap sampling design combines a grid-based sampling stratified by major habitats with the camera placement along a traditional monitoring route, and with an experimental set-up inside and outside large herbivore exclosures. This provides opportunities for studying the distribution, habitat use, activity, phenology, population structure and community composition of wildlife species and allows comparison of traditional with novel monitoring approaches. Images are transferred via application programming interfaces to external services for automated species identification and long-term data storage. A deep learning model for species identification was tested and showed promising results for identifying focal species. Furthermore, a detailed cost analysis revealed that establishment costs of the automated system are higher but the annual operating costs much lower than those for traditional camera trapping, resulting in the automated system being >40 % more cost-efficient. The developed end-to-end data pipeline demonstrates that continuous monitoring with automated wildlife camera networks is feasible and cost-efficient, with multiple benefits for extending the current monitoring methods. The system can be applied in open habitats of other nature reserves with mobile network coverage. [ABSTRACT FROM AUTHOR]

Maize is the most widely cultivated and major security crop in sub-Saharan Africa. Three foliar diseases threaten maize production on the continent, namely northern leaf blight, gray leaf spot, and southern corn leaf blight. These are caused by the fungi Exserohilum turcicum, Cercospora zeina, and Bipolaris maydis, respectively. Yield losses of more than 10% can occur if these pathogens are diagnosed inaccurately or managed ineffectively. Here, we review recent advances in understanding the population biology and management of the three pathogens, which are present in Africa and thrive under similar environmental conditions during a single growing season. To effectively manage these pathogens, there is an increasing adoption of breeding for resistance at the small-scale level combined with cultural practices. Fungicide usage in African cropping systems is limited due to high costs and avoidance of chemical control. Currently, there is limited knowledge available on the population biology and genetics of these pathogens in Africa. The evolutionary potential of these pathogens to overcome host resistance has not been fully established. There is a need to conduct large-scale sampling of isolates to study their diversity and trace their migration patterns across the continent. [ABSTRACT FROM AUTHOR]

In the past few decades, the discrete dynamics of difference maps have attained the remarkable attention of researchers owing to their incredible applications in different domains, like cryptography, secure communications, weather forecasting, traffic flow models, neural network models, and population biology. In this article, a generalized chaotic system is proposed, and superior dynamics is disclosed through fixed point analysis, time-series evolution, cobweb representation, period-doubling, period-3 window, and Lyapunov exponent properties. The comparative bifurcation and Lyapunov plots report the superior stability and chaos performance of the generalized system. It is interesting to notice that the generalized system exhibits superior dynamics due to an additional control parameter β . Analytical and numerical simulations are used to explore the superior dynamical characteristics of the generalized system for some specific values of parameter β . Further, it is inferred that the superiority in dynamics of the generalized system may be efficiently used for better future applications. [ABSTRACT FROM AUTHOR]

Species occupying dryland river ecosystems often experience "boom‐and‐bust" demographic cycles that coincide with shifts in habitat availability. Knowing whether declines are within natural thresholds versus those caused by acute human disturbance is critical for managing protected species. We investigated temporal shifts in abundance and habitat use of an endangered population of the threespine stickleback Gasterosteus aculeatus in southern California, where a Mediterranean climate leads to ephemeral habitat in one of the regions' least hydrologically modified rivers, the Santa Clara River. We conducted population surveys over a period of below‐average rainfall in the upper watershed in Soledad Canyon, with predefined reaches surveyed multiple times per year to capture different hydrologic conditions. Abundances were stable across years but varied significantly depending on location, with some reaches remaining dry and others drying seasonally to varying degrees. Occupancy models showed that the presence of stable perennial reaches, drying regime, and other site‐specific factors were important predictors of habitat use, and that certain reaches may be key to ensuring source‐sink dynamics as flow dissipates over the dry season. Low occupancy in two sections was driven by different predominant mechanisms, one by diel cycles of evapotranspiration and the other by cattails (Typha spp.), with both having greater effects during the hotter, drier parts of the year. As dryland river ecosystems are vulnerable to the effects of anthropogenic‐induced climate change, this study demonstrates how temporal monitoring can delimit dry‐state benchmarks for improving management interventions (i.e., translocation and habitat restoration) for protected species under conditions that are predicted to worsen in the coming years. [ABSTRACT FROM AUTHOR]

Genotype and phenotype in mobile organisms can be defined by various factors such as environmental, biological and geographical. Brown noddies Anous stolidus are pan-tropical seabirds breeding at different times, with migratory and resident populations in six islands throughout 20° of latitude in the Southwestern Atlantic Ocean. If environmental heterogeneity plays a key role in their population biology, we would expect significant genetic structure among colonies. However, absence of genetic structure between phenotypically different populations could play a scenario of ecological plasticity. To test these hypotheses, we used a model-based integrative approach combining genetic (mtDNA and ultraconserved elements) and morphological data of the brown noddy (n = 122) along with environmental variables and isotopic niches. We uncovered low levels of genetic structure, with 16 haplotypes for mtDNA and a signal of an ancient population expansion. Ultraconserved elements indicated that all colonies belong to the same genetic population (K = 1) and revealed substantial endogamy. However, phenotype differed both by biometric measures and isotopic niches between most pairs of populations. Although individuals from the northernmost colony are larger than the others, they are genetically similar, indicating a wide reaction norm for this species. Our results indicate the Southwestern Atlantic populations of the brown noddy are panmictic, but ecologically and morphologically diverse. [ABSTRACT FROM AUTHOR]

• Euphorbia schoenlandii has been heavily impacted by habitat loss and degradation. • There is a high degree of isolation between the three remaining populations. • Plants are negatively affected by the stem-boring larvae of nephopteryx divisella. • Extant populations are stable and recruiting overall, especially at coastal sites. Many threatened plant species in South Africa occur outside of protected areas and these include numerous succulent species that are traded internationally. Despite the potential impact that this may have on rare and endemic succulent species, limited population data exist to inform the non-detriment findings required by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) to ensure that international trade is sustainable. A concerted effort is being made in South Africa to gather such data for threatened succulents in the Euphorbiaceae. As part of this effort, the study set out to locate the extant populations of Euphorbia schoenlandii , an endemic of the Succulent Karoo, and acquire a better understanding of the population biology and ecology of the species. We applied the point-centred quarter method to estimate population size and density at each locality. This first-ever comprehensive field survey allowed for the determination of the geographic distribution of the species, as well as the sizes and number of populations. Biotic and abiotic environmental variables were employed to generate a habitat profile and a species distribution model for conservation purposes. Population structure, regeneration potential, and stability of the three known populations were also assessed. According to this study, approximately 29 152 individuals remain in the wild. It was shown that the species is often associated with nurse plants. Various potential pollinators were identified, but of concern was the considerable infestation by an alien snout moth (Nephopteryx divisella) , a known pest of euphorbias. The first adult size class contained the highest proportion of individuals, which is indicative of pulse recruitment. Seedling numbers were low, most likely because the surveys were conducted during a drought period. Overall, this study provides the first data on various aspects of the population structure and ecology of E. schoenlandii. It provides valuable information regarding current threats, and also highlights the vulnerability of the species to further habitat loss and degradation or future illegal or unregulated harvesting. [ABSTRACT FROM AUTHOR]

The dolphinfish (Coryphaena hippurus) is a mid-level trophic predator and migratory, cosmopolitan species of pelagic fish that is found throughout tropical and subtropical regions (Palko et al., 1982; Luckhurst, 2017; [...]

ABSTRACTIntroduction Transmissible vaccines offer a novel approach to suppressing viruses in wildlife populations, with possible applications against viruses that infect humans as zoonoses – Lassa, Ebola, rabies. To ensure safety, current designs propose a recombinant vector platform in which the vector is isolated from the target wildlife population. Because using an endemic vector creates the potential for preexisting immunity to block vaccine transmission, these designs focus on vector viruses capable of superinfection, spreading throughout the host population following vaccination of few individuals.Areas covered We present original theoretical arguments that, regardless of its R0 value, a recombinant vaccine using a superinfecting vector is not expected to expand its active infection coverage when released into a wildlife population that already carries the vector. However, if superinfection occurs at a high rate such that individuals are repeatedly infected throughout their lives, the immunity footprint in the population can be high despite a low incidence of active vaccine infections. Yet we provide reasons that the above expectation is optimistic.Expert Opinion High vaccine coverage will typically require repeated releases or release into a population lacking the vector, but careful attention to vector choice and vaccine engineering should also help improve transmissible vaccine utility.

Single gamete cell sequencing together with long-read sequencing can reliably produce chromosome-level phased genomes. In this study, we employed PacBio HiFi and Hi-C sequencing on a male Landrace pig, coupled with single-sperm sequencing of its 102 sperm cells. A haplotype assembly method was developed based on long-read sequencing and sperm-phased markers. The chromosome-level phased assembly showed higher phasing accuracy than methods that rely only on HiFi reads. The use of single-sperm sequencing data enabled the construction of a genetic map, successfully mapping the sperm motility trait to a specific region on chromosome 1 (105.40–110.70 Mb). Furthermore, with the assistance of Y chromosome-bearing sperm data, 26.16 Mb Y chromosome sequences were assembled. We report a reliable approach for assembling chromosome-level phased genomes and reveal the potential of sperm population in basic biology research and sperm phenotype research. An improved pig genome assembly is reported, using single sperm sequencing to reconstruct chromosome haplotypes, and with improved Y chromosome sequence. [ABSTRACT FROM AUTHOR]

This study investigated the biology, population parameters, and ecology of the sergestid shrimp (Acetes) in Barangay Damilisan, Miagao, Iloilo, the Philippines, by collecting samples for biological analyses and analyses using FiSAT II software. Based on morphometric evaluation, the sergestid shrimps present in the study site were identified as Acetes intermedius. Mature and near-spawning of the 180 specimens examined for ovarian maturity were > 50% in January, February, and April 2022. Size at sexual maturity was recorded at lengths ranging from 21.90-23.10 mm. The highest mean TL and CL were 20.49 ± 1.84 and 5.32 ± 0.56 mm, respectively, in January 2022. The length-frequency data showed that the highest frequency was 18.50-20.40 mm. The male-to-female sex ratio was 1:2; wherein females dominated the males. The highest frequency for females ranged from 20.50-22.40 mm (TL). Estimated population parameters of A. intermedius were L∞ = 30.98 mm, K = 1.900 yr-1, Ø' =3.26 yr-1, tmax= 1.6 yr-1, M = 3.93 yr-1, F = 4.07 yr-1, Z = 8.00 yr-1, E = 0.51, E0.1 = 0.517, E0.5 = 0.349, Emax = 0.691, L50%/Lc = 13.45 mm, and L75% = 14.57 mm with a unimodal type of recruitment pattern. The value obtained for the exploitation rate was above 0.5, hence suggesting that the Acetes stocks in Brgy. Damilisan faced overexploitation. These results provide information that can be used to properly conserve, utilize, and manage the Acetes fishery industry in Miagao, Iloilo, the Philippines. [ABSTRACT FROM AUTHOR]

Sustainable management and conservation strategies are crucial for any species of Gerreidae. Without comprehensive research on population biology, maintaining a balance between having healthy natural stocks and the socio-economic benefit of fisheries is difficult. Therefore, we studied some aspects of the biology of Gerres longirostris based on 474 specimens collected from the Red Sea (Jeddah coast, Saudi Arabia). The overall sex ratio of males to females was found to be 1:1.52, which was significantly different from the expected ratio of 1:1 (p < 0.05). Histological analysis of ovaries and testes and monthly variations in GSI values for G. longirostris indicated that spawning occurs between March and June, with a peak in GSI in May, and the trend was similar for both sexes. Size at 50% sexual maturity was estimated at 19.8 cm for females and 20.2 cm for males. The maximum batch and relative fecundity were estimated at 315,210 ova, 10,832 ova/cm, and 1068 ova/g, respectively. Batch fecundity and relative batch fecundity were significant correlated with total length (TL, cm) and body weight (BW, g) at p < 0.05. Histological examination of gonads revealed that their maturation in this species is asynchronous, with different developmental stages of oocytes at the same time, which indicates that the species is a multiple-batch spawner with indeterminate fecundity. [ABSTRACT FROM AUTHOR]

The historical challenges to bridge the gaps between developmental biology and population or statistical genetics under the explanatory dominance of the Modern Evolutionary Synthesis during the 20th century have been thoroughly documented. However, although several attempts to integrate these fields have been made, most have been deemed unsuccessful. As an example of those efforts, in this paper I discuss the work of James Meadows Rendel, a student of J. B. S. Haldane and disciple of Conrad Hal Waddington. I present his largely forgotten or unrecognized, but innovative, ideas about canalization and the role of development in phylogeny as a valuable piece to connect these fields that could still have important ramifications for today's evolutionary biology. In fact, it is expected that the legacy of J. M. Rendel will be rediscovered, and more importantly, incorporated and extended by future researchers, in light of the growth of evolutionary developmental biology in the last decades. What is more, this case offers a chance to critically revisit standard historiographies about the dichotomy between developmental and population genetics research frameworks in 20th century biology. • Rendel's theory integrated various developmental and evolutionary processes. • Rendel's theoretical work is generally omitted or unrecognized in the literature. • J. M. Rendel can be seen as a forerunner for contemporary Evo-Devo approaches. [ABSTRACT FROM AUTHOR]

The goal of evolutionary biology is to explain the diversity of the entire sweep of the natural world; population biology only examines tiny slices of time of a few individuals of single species. What gives the tiny scale of population biology its relevance to evolutionary biology is the following assumption: processes identical or similar to those observed in a given population biology study are operative in unexamined individuals in the same species, have been operative throughout the history of the species, and are operative in other species. Without this assumption, population biology studies are just very detailed descriptions of a handful of individuals of a species. Population biology lacks the means to test its jusifying assumption. It is tested by the comparative method, studies of convergent evolution across species. The comparative method has its own blind spots, mainly its inability to examine intraspecific variation, heritability, and fitness directly, exactly the purview of population biology. Population and comparative biology thus provide complementary sources of direct evidence regarding evolutionary process. Both, along with optimality models, evo-devo studies of the variants that can or can't be produced in development, together with assumptions about unseeable ancestral populations, make up essential parts of a maximally well-supported evolutionary explanation. Recognizing this essential epistemic interdependence shows why it is necessary to select sources of evidence from across population, comparative, optimality, and developmental studies, leading to collaboration rather than criticism across these fields, and stronger explanations accounting for the evolution of diversity in organismal form and function. [ABSTRACT FROM AUTHOR]

The landscape of scientific publishing is experiencing a transformative shift toward open access, a paradigm that mandates the availability of research outputs such as data, code, materials, and publications. Open access provides increased reproducibility and allows for reuse of these resources. This article provides guidance for best publishing practices of scientific research, data, and associated resources, including code, in The American Phytopathological Society journals. Key areas such as diagnostic assays, experimental design, data sharing, and code deposition are explored in detail. This guidance aligns with that observed by other leading journals. We hope the information assembled in this paper will raise awareness of best practices and enable greater appraisal of the true effects of biological phenomena in plant pathology. [ABSTRACT FROM AUTHOR]

Cydalima perspectalis (Walker 1859) (Lepidoptera: Crambidae) is a destructive pest that has recently been reported from the ancient Hyrcanian forests feeding on leaves and shoots of Buxus hyrcana Pojarkova.To gain a deeper insight into the biology and population dynamics of C. perspectalis, a laboratory population was studied under controlled conditions. The moth was reared on B. hyrcana at 25 ± 1°C, 65 ± 10% RH and 16 h:8 h (L:D), and the data obtained were used to build a life table, adjusted to allow for the evaluation of the stage duration, for both males and females.The mean adult survival was 11.94 ± 0.26 days, the pre‐oviposition period lasted, on average, for 6.71 ± 0.18 days and the mean fecundity attained was 58.19 ± 7.81 eggs/female. Newly emerged females had a life expectancy (exj) of 14 days and males 19 days.The intrinsic rate of increase for the population was 0.05 ± 0.00 days−1, and the net reproductive rate was 24.05 ± 3.95 offspring/female. The biological and ecological data obtained allowed for the estimation of C. perspectalis biotic potential, thus contributing to the development of sustainable control methods for this pest and, consequently, to a reduction of the damage caused to box trees. [ABSTRACT FROM AUTHOR]

Understanding how the early stages of sexual signal diversification proceed is critically important because these microevolutionary dynamics directly shape species trajectories and impact macroevolutionary patterns. Unfortunately, studying this is challenging because signals involve complex interactions between behavior, morphology, and physiology, much of which can only be measured in real-time. In Hawaii, male Pacific field cricket song attracts both females and a deadly parasitoid fly. Over the past two decades, there has been a marked increase in signal variation in Hawaiian populations of these crickets, including novel male morphs with distinct mating songs. We capitalize on this rare opportunity to track changes in morph composition over time in a population with three novel morphs, investigating how mate and parasitoid attraction (components of sexual and natural selection) may shape signal evolution. We find dramatic fluctuation in morph proportions over the three years of the study, including the arrival and rapid increase of one novel morph. Natural and sexual selection pressures act differently among morphs, with some more attractive to mates and others more protected from parasitism. Collectively, our results suggest that differential protection from parasitism among morphs, rather than mate attraction, aligns with recent patterns of phenotypic change in the wild. [ABSTRACT FROM AUTHOR]

Phytophthora cactorum is the most common causal agent of Phytophthora crown rot and leather rot of strawberry, but P. nicotianae is also responsible for the disease in Florida. Studies of P. nicotianae populations have suggested that different groups of genotypes are associated with different hosts; however, it is not yet clear how many lineages exist globally and how they are related to different production systems. The aim of this study was to determine the genetic relationships of P. nicotianae isolates from Florida strawberry with genotypes reported from other hosts, quantify the genetic variation on strawberry, and test for an association with nursery source. A total of 49 isolates of P. nicotianae were collected from strawberry plants originating from multiple nursery sources during six seasons of commercial fruit production in Florida. Microsatellite genotyping identified 28 multilocus genotypes on strawberry that were distinct among 208 isolates originating from various hosts and locations. Based on STRUCTURE analysis, two genetic groups were identified: one consisting of isolates from strawberry, and the other comprising samples from different hosts. Multilocus genotypes were shared among nursery sources, and populations defined by nursery were not differentiated. Both mating types were found among the isolates from North Carolina- and California-origin plants and in most strawberry seasons; however, a predominance of A1 was observed, and regular sexual reproduction was not supported by the data. This study reveals a unique genetic population of P. nicotianae associated with strawberry and emphasizes the vital role of nursery monitoring in mitigating disease spread. [ABSTRACT FROM AUTHOR]

Maize is the most widely cultivated and major security crop in sub-Saharan Africa. Three foliar diseases threaten maize production on the continent, namely northern leaf blight, gray leaf spot, and southern corn leaf blight. These are caused by the fungi Exserohilum turcicum, Cercospora zeina, and Bipolaris maydis, respectively. Yield losses of more than 10% can occur if these pathogens are diagnosed inaccurately or managed ineffectively. Here, we review recent advances in understanding the population biology and management of the three pathogens, which are present in Africa and thrive under similar environmental conditions during a single growing season. To effectively manage these pathogens, there is an increasing adoption of breeding for resistance at the small-scale level combined with cultural practices. Fungicide usage in African cropping systems is limited due to high costs and avoidance of chemical control. Currently, there is limited knowledge available on the population biology and genetics of these pathogens in Africa. The evolutionary potential of these pathogens to overcome host resistance has not been fully established. There is a need to conduct large-scale sampling of isolates to study their diversity and trace their migration patterns across the continent.

Abstract Background Natal dispersal, the distance between site of birth and site of first breeding, has a fundamental role in population dynamics and species’ responses to environmental changes. Population density is considered a key driver of natal dispersal. However, few studies have been able to examine densities at both the natal and the settlement site, which is critical for understanding the role of density in dispersal. Additionally, the role of density on natal dispersal remains poorly understood in long-lived and slowly reproducing species, due to their prolonged dispersal periods and often elusive nature. We studied the natal dispersal of the white-tailed eagle (Haliaeetus albicilla) in response to local breeder densities. We investigated the effects of the number of active territories around the natal site on (a) natal dispersal distance and (b) the difference between natal and settlement site breeder density. We were interested in whether eagles showed tendencies of conspecific attraction (positive density-dependence) or intraspecific competition (negative density-dependence) and how this related to settlement site breeder density. Methods We used a combination of long-term visual and genotypic identification to match individuals from their breeding site to their natal nest. We identified natal dispersal events for 355 individuals hatched between 1984 and 2015 in the Baltic Sea coast and Arctic areas of Finland. Of those, 251 were identified by their genotype. Results Individuals born in high-density areas dispersed shorter distances than those born in low-density areas, but settled at lower density breeding sites in comparison to their natal site. Eagles born in low natal area densities dispersed farther but settled in higher density breeding sites compared to their natal site. Conclusions We show that eagles might be attracted by conspecifics (positive density-dependence) to identify high-quality habitats or find mates, but do not settle in the most densely populated areas. This indicates that natal dispersal is affected by an interplay of conspecific attraction and intraspecific competition, which has implications for population dynamics of white-tailed eagles, but also other top predators. Furthermore, our study demonstrates the value of long-term collection of both nestling and (non-invasive) adult DNA samples, and thereafter using genotype matching to identify individuals in long-lived and elusive species.

A leading crisis in the United States is the opioid use disorder (OUD) epidemic. Opioid overdose deaths have been increasing, with over 100,000 deaths due to overdose from April 2020 to April 2021. This paper presents a mathematical model to address illicit OUD (IOUD), initiation, casual use, treatment, relapse, recovery, and opioid overdose deaths within an epidemiological framework. Within this model, individuals remain in the recovery class unless they relapse back to use and due to the limited availability of specialty treatment facilities for individuals with OUD, a saturation treatment function was incorporated. Additionally, a casual user class and its corresponding specialty treatment class were incorporated. We use both heroin and all-illicit opioids datasets to find parameter estimates for our models. Bistability of equilibrium solutions was found for realistic parameter values for the heroin-only dataset. This result implies that it would be beneficial to increase the availability of treatment. An alarming effect was discovered about the high overdose death rate: by 2046, the disorder-free equilibrium would be the only stable equilibrium. This consequence is concerning because it means the epidemic would end due to high overdose death rates. The IOUD model with a casual user class, its sensitivity results, and the comparison of parameters for both datasets, showed the importance of not overlooking the influence that casual users have in driving the all-illicit opioid epidemic. Casual users stay in the casual user class longer and are not going to treatment as quickly as the users of the heroin epidemic. Another result was that the users of the all-illicit opioids were going to the recovered class by means other than specialty treatment. However, the change in the relapse rate has more of an influence for those individuals than in the heroin-only epidemic. The results above from analyzing this model may inform health and policy officials, leading to more effective treatment options and prevention efforts.

Colletotrichum coccodes (Wallr.) Hughes is an asexual fungus with five vegetative compatibility groups. It was postulated that C. coccodes was isolated at the center of origin of potato at one time, and due to the movement of potato around the globe, the fungus was established on each continent but became bottlenecked and genetically unable to form stable heterokaryons via vegetative compatibility grouping (VCG) studies. The objectives of this study were (i) to determine if the VCGs around the world are related to the VCGs in Chile, (ii) to determine the diversity of C. coccodes populations in Chile, and (iii) to find any evidence for a cryptic sexual life cycle for this fungus. Worldwide C. coccodes populations have been found to be genetically correlated and belong to one or more C. coccodes-identified VCGs. The most distributed VCG in Chile was VCG2, which is the most common VCG in North America. We hypothesize that one or more VCGs had spread from Chile to the rest of the world. Precautions and further studies should be investigated by using other molecular markers and gene sequencing. [ABSTRACT FROM AUTHOR]

Decades after the publication of the first population studies on Neotropical butterflies, knowledge of their population biology remains scarce in the literature. Inconspicuous groups like the nymphalid subfamily Satyrinae are often overlooked, and studies that examine the demographics of these neglected groups are paramount for a more comprehensive understanding of insect population dynamics. The present paper addresses this dearth of information by describing the population biology of three common species of Euptychiina (Nymphalidae: Satyrinae) butterflies, Hermeuptychia atalanta, Cissia eous and Malaveria affinis, in a suburban area. A 13-month mark-release-recapture study was carried out in the grass lawns of the University of Campinas, São Paulo State Southeastern Brazil. The results showed that population parameters differ among the three studied species. For example, the population of H. atalanta is about five times that of C. eous, which is four times larger than that of M. affinis. Sex ratios were male-biased in H. atalanta and C. eous, but not in M. affinis (whose sex ratio was 1:1). Hermeuptychia atalanta and C. eous had mean adult lifespans of approximately one week, with no variation between sexes. Malaveria affinis, however, had a lifespan of approximately 11 days for males and just five days for females. Age structures were similar in all three species, with no recruitment peaks detected throughout the year. Sexual dimorphism, based on wing size, was not observed in H. atalanta, but a clear pattern of dimorphism with larger females was observed for the other two species. The present study is the first to describe population parameters for Euptychiina in detail, and one of the few focusing on population biology of butterflies in suburban areas. Indeed, the present results could help to define strategies of lawn management for the campus, aiming to increase local biodiversity and consequently improve ecosystem services. [ABSTRACT FROM AUTHOR]

Alternaria linariae is an economically important foliar pathogen that causes early blight disease in tomatoes. Understanding genetic diversity, population genetic structure, and evolutionary potential is crucial to contemplating effective disease management strategies. We leveraged genotyping-by-sequencing (GBS) technology to compare genome-wide variation in 124 isolates of Alternaria spp. (A. alternata, A. linariae, and A. solani) for comparative genome analysis and to test the hypotheses of genetic differentiation and linkage disequilibrium (LD) in A. linariae collected from tomatoes in western North Carolina. We performed a pangenome-aware variant calling and filtering with GBSapp and identified 53,238 variants conserved across the reference genomes of three Alternaria spp. The highest marker density was observed on chromosome 1 (7 Mb). Both discriminant analysis of principal components and Bayesian model-based STRUCTURE analysis of A. linariae isolates revealed three subpopulations with minimal admixture. The genetic differentiation coefficients (FST) within A. linariae subpopulations were similar and high (0.86), indicating that alleles in the subpopulations are fixed and the genetic structure is likely due to restricted recombination. Analysis of molecular variance indicated higher variation among populations (89%) than within the population (11%). We found long-range LD between pairs of loci in A. linariae, supporting the hypothesis of low recombination expected for a fungal pathogen with limited sexual reproduction. Our findings provide evidence of a high level of population genetic differentiation in A. linariae, which reinforces the importance of developing tomato varieties with broad-spectrum resistance to various isolates of A. linariae. [ABSTRACT FROM AUTHOR]

Close-kin mark-recapture (CKMR) is a method analogous to traditional mark-recapture but without requiring recapture of individuals. Instead, multilocus genotypes (genetic marks) are used to identify related individuals in one or more sampling occasions, which enables the opportunistic use of samples from harvested wildlife. To apply the method accurately, it is important to build appropriate CKMR models that do not violate assumptions linked to the species' and population's biology and sampling methods. In this study, we evaluated the implications of fitting overly simplistic CKMR models to populations with complex reproductive success dynamics or selective sampling. We used forward-in-time, individual-based simulations to evaluate the accuracy and precision of CKMR abundance and survival estimates in species with different longevities, mating systems, and sampling strategies. Simulated populations approximated a range of life histories among game species of North America with lethal sampling to evaluate the potential of using harvested samples to estimate population size. Our simulations show that CKMR can yield nontrivial biases in both survival and abundance estimates, unless influential life history traits and selective sampling are explicitly accounted for in the modeling framework. The number of kin pairs observed in the sample, in combination with the type of kinship used in the model (parent-offspring pairs and/or half-sibling pairs), can affect the precision and/or accuracy of the estimates. CKMR is a promising method that will likely see an increasing number of applications in the field as costs of genetic analysis continue to decline. Our work highlights the importance of applying population-specific CKMR models that consider relevant demographic parameters, individual covariates, and the protocol through which individuals were sampled. [ABSTRACT FROM AUTHOR]

Background: Natal dispersal, the distance between site of birth and site of first breeding, has a fundamental role in population dynamics and species' responses to environmental changes. Population density is considered a key driver of natal dispersal. However, few studies have been able to examine densities at both the natal and the settlement site, which is critical for understanding the role of density in dispersal. Additionally, the role of density on natal dispersal remains poorly understood in long-lived and slowly reproducing species, due to their prolonged dispersal periods and often elusive nature. We studied the natal dispersal of the white-tailed eagle (Haliaeetus albicilla) in response to local breeder densities. We investigated the effects of the number of active territories around the natal site on (a) natal dispersal distance and (b) the difference between natal and settlement site breeder density. We were interested in whether eagles showed tendencies of conspecific attraction (positive density-dependence) or intraspecific competition (negative density-dependence) and how this related to settlement site breeder density. Methods: We used a combination of long-term visual and genotypic identification to match individuals from their breeding site to their natal nest. We identified natal dispersal events for 355 individuals hatched between 1984 and 2015 in the Baltic Sea coast and Arctic areas of Finland. Of those, 251 were identified by their genotype. Results: Individuals born in high-density areas dispersed shorter distances than those born in low-density areas, but settled at lower density breeding sites in comparison to their natal site. Eagles born in low natal area densities dispersed farther but settled in higher density breeding sites compared to their natal site. Conclusions: We show that eagles might be attracted by conspecifics (positive density-dependence) to identify high-quality habitats or find mates, but do not settle in the most densely populated areas. This indicates that natal dispersal is affected by an interplay of conspecific attraction and intraspecific competition, which has implications for population dynamics of white-tailed eagles, but also other top predators. Furthermore, our study demonstrates the value of long-term collection of both nestling and (non-invasive) adult DNA samples, and thereafter using genotype matching to identify individuals in long-lived and elusive species. [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]

To understand the evolution, life-history tradeoffs, and population ecology of cavity nesters, it is critical to identify the avian lineages and circumstances in which birds excavate tree cavities. Woodcreepers (Furnariidae: Dendrocolaptinae; 56 species) are considered non-excavators dependent on existing cavities. We overturn this assumption by providing definitive evidence that the Lesser Woodcreeper (Xiphorhynchus fuscus, 23 g) is a facultative tree-cavity excavator. From 2007 to 2022 in the Atlantic forest of Misiones, Argentina, Lesser Woodcreepers nested in preexisting tree crevices (4 nests), or excavated cavities in trunks of large-diameter trees in advanced stages of decay (mean diameter: 58 cm, range: 22–121 cm, 22 nests). Nest entrances were vertically elongated and chambers were usually pocket like, excavated in the exterior of the trees (sapwood), with floors that curved along the trees’ circumference. Excavating woodcreepers pulled out elongated pieces of spongy, fibrous decayed wood, tapping only when inside cavities. Published and online photographs of nests of Xiphorhynchus species suggest that excavation may be widespread in the genus. Our observations that woodcreepers tore out elongated pieces of spongy wood (rather than hammering) are consistent with the idea that their long, thin bills are more resistant to torsion and less resistant to impact compared to the stouter bills of other excavators in Passeriformes and Piciformes. Research has tended to focus on birds with chisel-shaped bills, perforating harder sapwood to create nesting chambers in the center of heartrot-infected trees (resulting in typical woodpecker cavities, with circular floors). We hypothesize that Lesser Woodcreepers have adopted an alternative strategy, selecting large trunks with soft outer wood (sapwood), stopping their excavation radially if they reach harder wood, and then expanding the nest chamber laterally. Furnariidae may offer a useful model family for understanding ecological and evolutionary factors that influence cavity excavation. We provide a Spanish translation in Supplementary Material. [ABSTRACT FROM AUTHOR]

Wheat blast, caused by Pyricularia oryzae Triticum (PoT), is an emerging threat to global wheat production. The current understanding of the population biology of the pathogen and epidemiology of the disease has been based on phylogenomic studies that compared the wheat blast pathogen with isolates collected from grasses that were invasive to Brazilian wheat fields. In this study, we performed a comprehensive sampling of blast lesions in wheat crops and endemic grasses found in and away from wheat fields in Minas Gerais. A total of 1,368 diseased samples were collected (976 leaves of wheat and grasses and 392 wheat heads), which yielded a working collection of 564 Pyricularia isolates. We show that, contrary to earlier implications, PoT was rarely found on endemic grasses, and, conversely, members of grass-adapted lineages were rarely found on wheat. Instead, most lineages were host-specialized, with constituent isolates usually grouping according to their host of origin. With regard to the dominant role proposed for signalgrass in wheat blast epidemiology, we found only one PoT member in 67 isolates collected from signalgrass grown away from wheat fields and only three members of UrocMoa-adapted lineages among hundreds of isolates from wheat. Cross-inoculation assays on wheat and a signalgrass used in pastures (U. brizantha') suggested that the limited cross-infection observed in the field may be due to innate compatibility differences. Whether or not the observed level of crossinfection would be sufficient to provide an inoculum reservoir, or serve as a bridge between wheat growing regions, is questionable and, therefore, deserves further investigation. [ABSTRACT FROM AUTHOR]

Wheat blast, caused by the Pyricularia oryzae Triticum lineage (PoT), first emerged in Brazil and quickly spread to neighboring countries. Its recent appearance in Bangladesh and Zambia highlights a need to understand the disease's population biology and epidemiology so as to mitigate pandemic outbreaks. Current knowledge is mostly based on characterizations of Brazilian wheat blast isolates and comparison with isolates from non-wheat, endemic grasses. These foregoing studies concluded that the wheat blast population lacks host specificity and, as a result, undergoes extensive gene flow with populations infecting nonwheat hosts. Additionally, based on genetic similarity between wheat blast and isolates infecting Urochloa species, it was proposed that the disease originally emerged via a host jump from this grass and that Vrochloa likely plays a central role in wheat blast epidemiology owing to its widespread use as a pasture grass. However, due to inconsistencies with broader phylogenetic studies, we suspected that these seminal studies had not actually sampled the populations normally found on endemic grasses and, instead, had repeatedly isolated members of PoT and the related Lolium pathogen lineage (PoLl). Re-analysis of the Brazilian data as part of a comprehensive, global, phylogenomic dataset that included a small number of South American isolates sampled away from wheat confirmed our suspicion and identified four new P. oryzae lineages on grass hosts. As a result, the conclusions underpinning current understanding in wheat blast's evolution, population biology, and epidemiology are unsubstantiated and could be equivocal. [ABSTRACT FROM AUTHOR]

Hydrothermal vents host fragmented habitats and are increasingly becoming the target of deep-sea mining projects for their mineral resources. Managing a future sustainable exploitation requires a good understanding of the resilience of biological populations to natural and anthropogenic disturbances, hence a better knowledge of species life history traits and their capacity to replenish local populations or colonise distant sites. In this context, we studied the reproductive biology and recruitment patterns of three main representative hydrothermal vent limpets of the South West Pacific back-arc basins, Lepetodrilus schrolli, Lepetodrilus fijiensis and Shinkailepas tollmanni, in relation to habitats and environmental conditions. Limpets were collected in Bathymodiolus and Ifremeria nautilei habitats at several vent sites in the Manus, North Fiji and Lau back-arc basins, and the Futuna Volcanic Arc during the CHUBACARC cruise in 2019. Population structure, gonad morphology, and gametogenesis were analysed for each species, and fecundity was analysed for the two Lepetodrilus species. Both Lepetodrilus spp. were gonochoric and displayed a sexual size dimorphism with females larger than males. Gametogenesis was continuous or quasi-continuous with all stages of oocyte development present in the gonad and a maximum oocyte size of 124 µm for L. schrolli and 126 µm for L. fijiensis. Fecundity varied between 52 and 205 with a mean of 119 ± 74 (SD) matured oocytes per female in L. schrolli and between 80 and 605 with a mean of 366 ± 183 (SD) matured oocytes per female in L. fijiensis, and was independent of the limpet size for both species. Shinkailepas tollmanni is also a gonochoric gastropod with continuous gametogenesis and a maximum oocyte size of 153 µm. For each species, size-frequency distributions were consistent with a continuous recruitment although episodic larval supply could blur the signal. There was no evidence of an influence of the habitat type nor environmental conditions on population structures. [ABSTRACT FROM AUTHOR]

The seemingly paradoxical increase of a species' means density in response to greater mortality is an interesting research topic in recent times, and such a type of counterintuitive response is known as the hydra effect. Identifying and predicting the consequences of increased mortality is crucial for conservation biology and population management. The existence of the hydra effect in Gause-type models is a known feature in mathematical ecology. However, the hydra effect is still not investigated in mathematical models of predator-dependent functional responses. The present paper addresses the presence of a hydra effect in either the prey and predator species of two-species unstructured predator-dependent functional response models with logistic prey growth and density-independent predator death rate. Our results show that the positive density-dependence of predators (grouping behavior or cooperation) in trophic functions shows a hydra effect in the prey species, whereas the negative density-dependence of predators (interference) shows a hydra effect in the predator species. Moreover, in the former case, prey always exhibits the hydra effect at a stable state, whether in the latter case, predator exhibits the hydra effect at a stable state when the prey has positive self-effects at the equilibrium. In our considered models, the prey's positive self-effects suggest that the intraspecific competition rate coefficient would be sufficiently small so that the species density would be positively related to its per capita growth rate. In the case of cyclic dynamics, the hydra effect is a typical feature of predator species for unstable systems with saturating functional responses. [ABSTRACT FROM AUTHOR]

Context. Efficient monitoring of herpetofauna can prove challenging to agencies and NGOs responsible for their management. Wildlife cameras have been proposed as a method to monitor herpetofauna; however, estimates of detection rates and factors affecting detection by cameras are generally lacking and therefore limiting their application. Aims. We determined the effect of body size and temperature differential on the detection of snakes and frogs by passive infrared (PIR) wildlife cameras. We hypothesised that detection would differ among models and be positively correlated with body size and surface-temperature differential between the animal and substrate. We then conducted a field study to compare the detection of herpetofauna by a traditional method with PIR cameras. Methods. We tested 10 cameras of seven models on five snakes and one camera on six frogs. Photographs were downloaded to determine the detection rate of each species by each camera. We then chose a camera model to compare two herpetofauna survey methods, namely, drift fences equipped with cameras and visualencounter surveys. Surveys were conducted monthly over 12 months in Irwin County, GA, USA. Key results. The highest mean detection rates of snakes were 0.65 (s.e. = 0.33), 0.50 (s.e. = 0.34), and 0.49 (s.e. = 0.34) for the Browning Dark Ops, Reconyx Hyperfire 2, and Mossy Oak Covert Scouting Camera respectively. The detectability of larger snakes was greater than that of smaller snakes and increased as the absolute temperature differences between the snake and the substrate increased. The detectability of frogs was influenced by absolute temperature differential alone. PIR cameras generated five times more observations, documented more herpetofauna species, and were seven times more efficient than traditional surveys. Conclusions. The effectiveness of PIR cameras to detect herpetofauna varies among models and depends on the likelihood that the animal will have a body temperature significantly different from the temperature of the substrate. PIR cameras generated observations far more efficiently than traditional sampling methods. Implications. PIR wildlife cameras may be most effective at detecting larger, diurnal herpetofauna and least effective at detecting smaller, nocturnal species. Wildlife cameras have the potential to efficiently monitor some herpetofauna, providing a means to better evaluate management objectives. [ABSTRACT FROM AUTHOR]

ABSTRACTAmong genes present in all group A streptococci (GAS), those encoding M-fibril and T-pilus proteins display the highest levels of sequence diversity, giving rise to the two primary serological typing schemes historically used to define strain. A new genotyping scheme for the pilin adhesin and backbone genes is developed and, when combined with emm typing, provides an account of the global GAS strain population. Cluster analysis based on nucleotide sequence similarity assigns most T-serotypes to discrete pilin backbone sequence clusters, yet the established T-types correspond to only half the clusters. The major pilin adhesin and backbone sequence clusters yield 98 unique combinations, defined as “pilin types.” Numerous horizontal transfer events that involve pilin or emm genes generate extensive antigenic and functional diversity on the bacterial cell surface and lead to the emergence of new strains. Inferred pilin genotypes applied to a meta-analysis of global population-based collections of pharyngitis and impetigo isolates reveal highly significant associations between pilin genotypes and GAS infection at distinct ecological niches, consistent with a role for pilin gene products in adaptive evolution. Integration of emm and pilin typing into open-access online tools (pubmlst.org) ensures broad utility for end-users wanting to determine the architecture of M-fibril and T-pilus genes from genome assemblies.IMPORTANCEPrecision in defining the variant forms of infectious agents is critical to understanding their population biology and the epidemiology of associated diseases. Group A Streptococcus (GAS) is a global pathogen that causes a wide range of diseases and displays a highly diverse cell surface due to the antigenic heterogeneity of M-fibril and T-pilus proteins which also act as virulence factors of varied functions. emm genotyping is well-established and highly utilized, but there is no counterpart for pilin genes. A global GAS collection provides the basis for a comprehensive pilin typing scheme, and online tools for determining emm and pilin genotypes are developed. Application of these tools reveals the expansion of structural-functional diversity among GAS via horizontal gene transfer, as evidenced by unique combinations of surface protein genes. Pilin and emm genotype correlations with superficial throat vs skin infection provide new insights on the molecular determinants underlying key ecological and epidemiological trends.

We consider age-structured models with an imposed refractory period between births. These models can be used to formulate alternative population control strategies to China's one-child policy. By allowing any number of births, but with an imposed delay between births, we show how the total population can be decreased and how a relatively older age distribution can be generated. This delay represents a more 'continuous' form of population management for which the strict one-child policy is a limiting case. Such a policy approach could be more easily accepted by society. Our analyses provide an initial framework for studying demographics and how social constraints influence population structure.

• Euphorbia bupleurifolia populations have undergone a drastic decline. • Bell-shaped size class distribution (SCD) patterns were dominant. • Populations are structured through adult persistence, not high seedling recruitment. • Plants persist in sites with high bare ground cover and minimal overstorey shade. • Harvesting, inappropriate fire frequencies and habitat degradation are threats. Many South African succulent Euphorbia spp. are threatened by anthropogenic activities such as habitat loss and illegal harvesting. However, only a few species have been studied in sufficient detail to aid their conservation through the development of effective management plans. This study documents the distribution, abundance, and population biology of the formerly widespread Euphorbia bupleurifolia , a species endemic to the Eastern Cape and KwaZulu-Natal provinces of South Africa. Until recently, the status of wild populations of this species was largely unknown. Searches for plants in each of the 31 previously recorded localities revealed that only nine populations (29 %) still had plants in 2018, indicating a contraction of the distribution, with the species apparently now ranging from Makhanda to Port Edward. Population size and structure, flowering, microhabitat requirements and various other factors, including potential threats and disturbances, were quantified for the nine populations. Complete counts were conducted, and the diameters of plants were measured and canopy areas calculated. Population sizes varied from one (effectively extinct) to 675 plants (with a total of 1724 plants recorded across all populations). Measurements of cultivated plants at the Walter Sisulu National Botanical Garden established that the onset of reproduction can be expected for a plant with a canopy area of 2.63 cm2, and annual growth rates of 0.55±8.37 cm2 are possible. Bell-shaped size class distribution (SCD) patterns were dominant, which is attributed to an adult persistence population survival strategy. Unsustainable harvesting, inappropriate fire frequencies as well as habitat loss and degradation remain a threat to the species. Euphorbia bupleurifolia persists mostly in sites with low vegetation biomass, high bare ground cover and minimal overstorey shade. This study highlights the drastic decline of a Least Concern species, formally considered widespread (i.e. common), and provides baseline demographic data, which may be employed in future monitoring and management of the remaining populations, to improve the conservation of E. bupleurifolia. Intensified field surveys involving citizen science programmes (e.g. CREW) and subsequent uplisting of the species to a higher Red List threat category is recommended. [ABSTRACT FROM AUTHOR]

All the time, differential dynamical models with delay has witness a tremendous application value in characterizing the internal law among diverse biological populations in biology. In the current article, on the basis of the previous publications, we formulate a new Lotka–Volterra commensal symbiosis system accompanying delay. Utilizing fixed point theorem, inequality tactics and an appropriate function, we gain the sufficient criteria on existence and uniqueness, non-negativeness and boundedness of the solution to the formulated delayed Lotka–Volterra commensal symbiosis system. Making use of stability and bifurcation theory of delayed differential equation, we focus on the emergence of bifurcation behavior and stability nature of the formulated delayed Lotka–Volterra commensal symbiosis system. A new delay-independent stability and bifurcation conditions on the model are presented. By constructing a positive definite function, we explore the global stability. By constructing two diverse hybrid delayed feedback controllers, we can adjusted the domain of stability and time of appearance of Hopf bifurcation of the delayed Lotka–Volterra commensal symbiosis system. The effect of time delay on the domain of stability and time of appearance of Hopf bifurcation of the model is given. Matlab experiment diagrams are provided to sustain the acquired key outcomes. [ABSTRACT FROM AUTHOR]

Population dynamics can be influenced by physical and biological factors, particularly in stressful environments. Introduced species usually have great physiological plasticity, resulting in populations with different traits. Undaria pinnatifida, a macroalga originally described from northeast Asia, was introduced in Northern Patagonia, Argentina (San Matías Gulf) around 2010. To describe the spatio‐temporal variability in population structure and morphometry of U. pinnatifida, we conducted monthly field samplings for 2 years at the intertidal area of two contrasting sites in the San Matías Gulf. Individuals of U. pinnatifida were classified by developmental stage, and their morpho‐gravimetric variables were measured. In both intertidal sites juveniles were found in higher proportion during austral autumn and grew and matured during the autumn‐winter months (from May onwards), and individuals senesced during early austral summer (December and January). Conversely, density and biomass were largely different between sites, and individuals showed slight morphological variability between sites. Environmental (e.g., nutrient concentration, available substrate) and biological factors (e.g., facilitation, competition) may explain the observed differences. Since there is not a macroalga with U. pinnatifida morphometrical characteristics in the intertidal environments of San Matías Gulf, studying this recent introduction gives us a better understanding of its potential ecological effects. [ABSTRACT FROM AUTHOR]

With populations declining across their geographic range, the spotted turtle (Clemmys guttata) is currently a species of conservation concern. Though broadly distributed, the species is particularly enigmatic at its southern periphery, and many aspects of its ecology and population biology in this portion of the range have either just recently been described or are currently unknown. One of the current knowledge gaps is a robust assessment of the population genetics of the southern populations. We collected tissue samples from 204 spotted turtles from 5 sites across South Carolina, Georgia, and Florida and used 11 microsatellite loci to investigate the genetic diversity and population structure in these populations. We found that southern populations exhibited low, but significant, population differentiation (mean FST = 0.062) and each site clustered as its own genetic group. Genetic diversity across sites was comparable to estimates reported for northern populations. Net effective population sizes were generally robust and no populations showed indication of recent bottlenecks. Our results suggest that populations inhabiting relatively intact environments do not appear to face immediate threats from past loss of genetic diversity. However, continued monitoring, both demographic and genetic, of this long-lived species is an important management goal to insure that continued global changes do not threaten population viability. [ABSTRACT FROM AUTHOR]

Pakistan faces tremendous challenges in providing healthcare due to a lack of consistent policymaking, increasing expenditure and exponential growth in population since its inception in 1947. These challenges are not just driven by politics, policy and allocation of resources but also by healthcare, environment and characteristics of the population biology. Clinical trials provide the best way to find population-specific, cost-effective treatments that do not merely mimic those used in wealthier nations. This article analyzes all clinical studies conducted with at least one site in Pakistan listed on ClinicalTrials.gov, combined with a short overview that considers new therapeutic approaches that can be investigated in future clinical trials. Therapies using repurposed medicines are of particular interest as they use affordable drugs that are already widely available. [ABSTRACT FROM AUTHOR]

The goal of this perspective is to review how seagrass research has evolved over the past half century to our current state of knowledge. We review how our knowledge of seagrass ecosystems changed from the pre-1970s when so little was known about seagrasses and how it progressed during the next 5 decades when seagrass knowledge rapidly expanded. Here, we concentrate on accomplishments in the areas of reproductive biology and ecology, population biology, seagrass-animal relationships, conservation and restoration, and mapping and monitoring. We also look ahead and discuss some areas that are ripe for future research, especially those employing new mapping and monitoring technologies, improved restoration methods that include multiple genetic variants, rhizosphere studies that result in a deeper understanding of microbial effects on nitrogen availability, sulfide levels and carbon sequestration, and how changing climatic regimes and tropicalization will likely affect temperate and tropical seagrass-dominated ecosystems. [ABSTRACT FROM AUTHOR]

Calonectria pseudoreteaudii is an important causal agent of Eucalyptus leaf blight in southern China. This pathogen causes Eucalyptus tree disease across numerous regions in southern China. In addition to diseased leaves, C. pseudoreteaudii has occasionally been isolated from soil in Eucalyptus plantations. The aim of this study was to clarify whether C. pseudoreteaudii causing Eucalyptus leaf blight in China is mainly clonally reproduced and to determine the potential spreading mechanism of C. pseudoreteaudii between diseased leaves and soil. To this end, 10 polymorphic microsatellite markers were analyzed to detect the genetic diversity of 97 C. pseudoreteaudii isolates from diseased leaves and soil in a Eucalyptus plantation in Guangxi Zhuang Autonomous Region, southern China. The analysis showed that the genetic diversity of the isolates from both the diseased leaves and soil was high. However, the gene and genotype diversity of the C. pseudoreteaudii isolates from diseased leaves were higher than those of the isolates from the soil. Moreover, all genotypes detected in the isolates from the soil were also found in the isolates from the diseased leaves. Structural analyses did not show clear population structures related to the population substrates of the diseased leaves or soil, and molecular variance analyses indicated that no significant genetic differentiation existed between the diseased leaf and soil populations. These results suggest that C. pseudoreteaudii in soil spreads from diseased leaves, and that an asexual cycle is the primary reproductive mode in both diseased leaf and soil populations. This is the first study on the genetic diversity and population structure of C. pseudoreteaudii. The high genetic diversity and spread pathways of this pathogen may pose challenges in controlling the disease. C. pseudoreteaudii from both diseased leaves and soils in Eucalyptus plantations needs to be carefully monitored for disease control and management. [ABSTRACT FROM AUTHOR]

One of the recent attempts to address the Hubble and S 8 tensions is to consider that the Universe started out not as a de Sitter-like spacetime, but rather anti-de Sitter-like. That is, the Universe underwent an "AdS-to-dS" transition at some point. We study the possibility that there are two dark energy fluids, one of which gave rise to the anti-de Sitter-like early Universe. The interaction is modeled by the Lotka–Volterra equations commonly used in population biology. We consider "competition" models that are further classified as "unfair competition" and "fair competition". The former involves a quintessence in competition with a phantom, and the second involves two phantom fluids. Surprisingly, even in the latter scenario it is possible for the overall dark energy to cross the phantom divide. The latter model also allows a constant w "AdS-to-dS" transition, thus evading the theorem that such a dark energy must possess a singular equation of state. We also consider a "conversion" model in which a phantom fluid still manages to achieve "AdS-to-dS" transition even if it is being converted into a negative energy density quintessence. In these models, the energy density of the late time effective dark energy is related to the coefficient of the quadratic self-interaction term of the fluids, which is analogous to the resource capacity in population biology. [ABSTRACT FROM AUTHOR]

Trophic interactions underpin the structure of ecological communities by describing the rates at which consumers exploit their resources. The rates at which predators consume their prey are influenced by prey traits, with many species inducing defensive modifications to prey traits following the threat of predation. Here we use different clonal lines of the protist Paramecium being consumed by Stenostomum predators to highlight how differences in prey traits impact rates of predation. Clonal lines differed in their body width traits, and in their ability to induce changes in body width. By using a factorial cross of predator and prey abundances for different clonal lines we demonstrate how evolutionary or induced alterations in prey traits can impact the relative threat of predation. Our experiments show how interference among predators impacts predation rate, and how increased body width increased predator handling times. Given that reductions in the strength of interspecific interactions are associated with increased levels of overall community stability, our results indicate how individual level changes may scale up to impact whole communities. [ABSTRACT FROM AUTHOR]

Contesting ideas about what is "normal" human behavior or biology is a core contribution of anthropology. In efforts to provide more inclusive views of what it means to be human, anthropologists challenge judgments about diverse ways of being, which include assumptions about what it means to be normal. Meanings of the term normal encompass the descriptive (statistical) and the evaluative (normative), i.e., judgments about a given characteristic. In biomedicine, "healthy" is often the value ascribed to normal, but embedded in healthy are biases that derive from particular cultural and historical contexts. Here I review how the term normal is understood and used in anthropological and related studies of human biology and biological variation. I propose the biological normalcy framework for understanding how the statistical and normative meanings of normal mutually inform each other and their consequences for human population biology. Several examples provide illustrations of the framework. [ABSTRACT FROM AUTHOR]