Search

Aristotle is often named as the first zoologist or biologist because of his writings on animals. Although Aristotle's major intention in these books was to illustrate his ideas of how knowledge and understanding might advance, at least one modern biologist (C. Darwin) has recognized Aristotle's depth and breadth as being of surviving merit. Of greater surprise is the ongoing attention that his works continue to receive, including publications in contemporary scientific journals. This review identifies 38 peer-reviewed papers on various topics from Aristotle's biological writings that have been published during the last 50 years. These papers are described according to content (genetics, population biology, anatomy, brain, movement), specific creatures (fish, scorpions, elephants, insects, birds), publication outlet, distribution over the fifty year period surveyed, and visible trends in the topics studied. It is concluded that, in the highly-competitive field of peer-reviewed scientific publication and citation, Aristotle's biology continues to excite the interest of scientists and remains salient to modern science itself. [ABSTRACT FROM AUTHOR]

Due to significant advances in instrumentation, many previously specialized techniques have become "routine" in user facilities. However, detailed knowledge held by experts has often not been relayed to general users, so they often rely on entry-level information, basic principles, and comparison with literature results for data analysis. As a result, major errors in the data analysis of multiple surface and material analysis techniques, including in x-ray photoelectron spectroscopy (XPS), have been appearing in the scientific literature. Representative examples of serious errors in XPS data analysis are shown in this work. We suggest that surface and material analysis, and perhaps even science in general, are in a state of "pre-crisis." We use two (logistic) models from population biology to suggest that bad analyses self-correct if they remain below a critical number. However, beyond a threshold, the literature can become useless because of the perpetuation of faulty analyses and concomitant loss of its self-correcting ability. XPS is used by scientists in many communities because of the power of the technique and high-quality instrumentation that is commercially available. Those who make new surfaces and materials face unique challenges because of the large number of surface and material analytical techniques that are often needed to characterize their materials. Graduate students and post-docs are often provided with only minimal instruction on using surface and material characterization methods. High fees for instruments may affect both the quality and the quantity of the data people collect. The Prisoner's Dilemma is a model from game theory that describes situations with reward structures that encourage uncooperative behavior and lead to suboptimal outcomes. However, the outcomes of Prisoner's Dilemma are not inevitable—their consequences change if their reward structures change. The current system does not appear to incentivize detailed learning of surface and material characterization techniques and careful material characterization. Prisoner's dilemmas appear to lead to other undesirable consequences in science. The concerns raised in this work suggest that many manuscripts are incompletely reviewed at present. The different stakeholders in this problem, including authors, research advisers, subject matter experts, reviewers, scientists who notice examples of faulty data analysis, editors, journals and publishers, funding agencies, scientific societies, leaders at universities and research centers, and instrument vendors, can improve the current situation. This work provides specific recommendations for each of these stakeholders. For example, we believe that authors are primarily responsible for the correctness of their work, not reviewers or editors; we question the wisdom of listing the names of the editor and reviewers on a paper; we are grateful for the significant contributions that have been made by subject matter experts to produce standards and tutorial information; the high cost of instrument time at some institutions may limit student access and result in suboptimal analyses; staff scientists often need to be better recognized for their intellectual contributions to studies; publishers may wish to allow selective reviewing of specific sections of papers related to material characterization; the reviewing at some open access journals may be inadequate; while it had its shortcomings, the pre-open access model of publishing incentivized the production and publication of high-quality work; audits of the products (scientific papers) of funding agencies may be necessary; collaboration needs to be encouraged to a greater extent at some institutions; and instrument vendors should not suggest to potential customers that surface characterization, e.g., by XPS, is trivial or simple. [ABSTRACT FROM AUTHOR]

Over the past several decades, biomarkers have become indispensable tools in human biology, allowing researchers to investigate biocultural and evolutionary questions and to generate basic data on health and well‐being. Human biologists are central players in biomarker methods development, pioneering the creation of "field friendly," minimally invasively collected biomarker approaches, as well as leading the innovative use of biomarkers, most notably to map the complex pathways from social and environmental conditions to altered physiology to health effects. This special issue, Part 2 of a collection focused on minimally invasively collected biomarkers, is comprised of nine papers that jointly contribute to driving the science of biomarker methods development and application. This compilation of papers engages with topics such as biological normalcy, ecoimmunology, and the ethics of working with vulnerable and underserved populations. It also focuses attention on research areas at present not emphasized in human biology such as bone turnover markers as a window onto osteoporosis and osteoarthritis and the use of cancer‐related biomarkers in population screening and epidemiology. Taken together, these papers help draw the roadmap for future biomarker work, emphasizing: (1) the need for systematic and transparent approaches to assay validation, with open access publication; (2) simultaneous measurement of multiple biomarkers and expanded use of instrument platforms that increase the range of physiological, genomics, and omics markers available to researchers; and, (3) increased attention to ethics and researcher responsibilities, encouraging a mindset that recognizes our obligation to provide benefits to individuals and communities and to help redress past abuses. [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]

In the 1960s, theoretical biologist Richard Levins criticised modellers in his own discipline of population biology for pursuing the "brute force" strategy of building hyper-realistic models. Instead of exclusively chasing complexity, Levins advocated for the use of multiple different kinds of complementary models, including much simpler ones. In this paper, I argue that the epistemic challenges Levins attributed to the brute force strategy still apply to state-of-the-art climate models today: they have big appetites for unattainable data, they are limited by computational tractability, and they are incomprehensible to the human modeller. Along the lines Levins described, this uncertainty generates a trade-off between realistic, precise models with predictive power and simple, highly idealised models that facilitate understanding. In addition to building ensembles of highly complex dynamical models, climate modellers can address model uncertainty by comparing models of different types, such as dynamical and data-driven models, and by systematically comparing models at different levels of what climate modellers call the model hierarchy. Despite its age, Levins' paper remains incredibly insightful and should be considered an important entry into the philosophy of computational modelling. [ABSTRACT FROM AUTHOR]

The scope of this paper can be clarified by means of a well-known phenomenon that is usually called 'industrial melanism': the fact that the melanic form of the peppered moth became dominant in industrial areas in England in the second half of the nineteenth century. Such changes in relative phenotype frequencies are important explananda for population biologists. Apart from trying to explain such changes over time, population biologists also often try to explain differences between populations, e.g. why yellow shell colour is dominant in certain colonies of land snails and almost absent in other colonies. The causal explanations that are given to address such explananda are the objects of analysis in this paper. Our primary aim is to explicate their structure: we want to capture the typical ingredients of causal explanations in population biology, and their organisation. Based on this explication, we discuss how natural selection fits into recent mechanical philosophy of science, and engage in the debate on the nature of evolutionary theory. [ABSTRACT FROM AUTHOR]

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Sherwin Carlquist's work was filled with inferences of xylem function, and yet he did not carry out xylem physiological or biomechanical measurements. Moreover, his quantitative analyses were rudimentary and he disliked the standard scientific practice of quantifying uncertainty with statistical analyses. Also, took few pains to explain to other functional xylem biologists why his comparative approach was useful and appropriate. Here, I discuss why nevertheless his papers are extremely valuable contributions to inferences of xylem function. The most important insight is that Sherwin used a valid and essential approach for the inference of biological function, known as the comparative method. Together with optimality models, population biology (including xylem physiology), and studies of developmental potential, the comparative method is an indispensable part of a maximally supported inference of xylem structure–function relation. Detecting his insightful inferences of function often requires reading around his various idiosyncrasies, including the lack of statistics and instead his reliance on his extraordinary memory to detect patterns. With this guide to reading Carlquist's work, I hope to give functional xylem physiologists better access to the richest and most wide-ranging body of functional hypotheses found in the xylem literature. [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 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]

Copyright of Canadian Journal of Plant Pathology is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

Over the past two decades, the range of the desert wheatear has expanded and the species has started breeding in northwestern Kazakhstan. There are, however, almost no studies on the breeding biology of this northwesternmost population. In this paper, we provided data on the breeding biology and space use of the desert wheatear near the village of Isatai, Atyrau Region, Kazakhstan. In 2012–2016, no fewer than 17 breeding pairs bred each year as a dense settlement next to Isatai within a 650 × 470 m plot. The local density was thus 0.55 pairs per ha, and the distance between the neighboring pairs was usually less than 100 m. Such dense settlements seem to be unusual for the desert wheatear in Kazakhstan. We assume that the local features of limited cattle grazing may have caused the formation of this dense settlement. At the same time, the habitat and nest site selections, as well as the breeding phenology, of the desert wheatear in the vicinity of Isatai are generally the same as in southern Kazakhstan (i.e., in the central part of the species' range). [ABSTRACT FROM AUTHOR]

Copyright of Folia Pomeranae Universitatis Technologiae Stetinensis Agricultura Alimentaria Piscaria et Zootechnica is the property of West Pomeranian University of Technology in Szczecin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper is a contribution to the modeling–methodological development of the application of mathematical systems theory in population biology. A discrete-time nonlinear Leslie-type model is considered, where both the reproduction and survival rates decrease as the total population size increases. In this context, the monitoring problem means that, from the observation of the size of certain age classes as a function of time, we want to recover (estimate) the whole state process (i.e., the time-dependent size of the rest of the classes). First, for the linearization approach, conditions for the existence and asymptotic stability of a positive equilibrium are obtained, then the discrete-time observer design method is applied to estimate an unknown state trajectory near the equilibrium, where we could observe a single age class. It is also shown how the observer design can be used to detect an unknown change in the environment that affects the population dynamics. The environmental change is supposed to be generated by additional dynamics (exosystem). Now, the Leslie-type model is extended with this exosystem, and the observer design is applied to this extended system. In this way, an estimation can be obtained for different (constant or periodic) environmental changes as well. [ABSTRACT FROM AUTHOR]

In the 1960s, scientists fascinated by the behavior of free‐living animals founded research projects that expanded into multi‐generation investigations. This paper charts the history of three scientists' projects to uncover the varied reasons for investing in a "long‐term" perspective when studying animal behavior: Kenneth Armitage's study of marmots in the Rocky Mountains, Jeanne Altmann's analysis of baboons in Kenya, and Timothy Hugh Clutton‐Brock's studies (among others) of red deer on the island of Rhum and meerkats in the Kalahari. The desire to study the behavior of the same group of animals over extended periods of time, I argue, came from different methodological traditions – population biology, primatology, and sociobiology – even as each saw themselves as contributing to the legacy of ethology. As scientists embraced and combined these approaches, a small number of long‐running behavioral ecology projects like these grew from short pilot projects into decades‐long centers of intellectual gravity within behavioral ecology as a discipline. By attending to time as well as place, we can see how this long‐term perspective was crucial to their success; they measured evolutionary changes over generations of animals and their data provided insights into how the animals they studied were adapting (or not) to changing local and global environmental factors. [ABSTRACT FROM AUTHOR]

Most amphibians have a complex life cycle with an aquatic larval and an adult (semi-) terrestrial stage. However, studies concerning spatial behaviour and orientation mainly focus on either the aquatic larvae or the adult animals on land. Consequently, behavioural changes that happen during metamorphosis and the consequences for emigration and population distribution are less understood. This paper aims to summarize the knowledge concerning specific topics of early amphibian life history stages and proposes several testable hypotheses within the following fields of research: larval and juvenile orientation, influences of environmental and genetic factors on juvenile emigration, their habitat choice later in life as well as population biology. I argue that studying larval and juvenile amphibian spatial behaviour is an understudied field of research, however, could considerably improve our understanding of amphibian ecology. [ABSTRACT FROM AUTHOR]

This paper discusses the catch trends, population attributes and biological characteristics of tilapiine species that are both native and that have been introduced into Lake Victoria and Lake Naivasha. Predation by Lates niloticus, species hybridisation, overfishing, pollution and eutrophication have negatively impacted endemic fish stocks in these lakes. Four tilapiine species, Oreochromis niloticus, Oreochromis leucostictus, Coptodon zillii and Coptodon rendalli, and three tilapiine species, O. niloticus, C. zillii and O. esculentus, were hence introduced into Lake Victoria and Lake Naivasha, respectively, to improve fish catches following collapse of native fish stocks. Establishment of these non-native species was associated with declines in populations of the native Oreochromis esculentus and Oreochromis variabilis, and O. niloticus now dominates commercial tilapiine fishery in Lake Victoria. The fishery catches in Lake Naivasha were dominated by the introduced O. leucostictus and O. niloticus, whereas C. zillii is rarely caught. The biological and population attributes of the tilapiines in both lakes have shown great variations over time. There is, therefore, a need for implementation of effective management measures, including control of fishing effort, pollution control and protection of surrounding wetlands, to promote recovery and long-term sustainability of the fishery resources of these lakes. [ABSTRACT FROM AUTHOR]

Traveling wave propagation is a significant phenomenon observed in population biology. Due to the occurrence of nonlocal effect in recursive systems, a deep understanding of the wavefront in the propagation direction (speed sign) is challenging. In this paper we study the sign of wave speed for bistable traveling waves to a two-species competitive system that biologically models the dynamics of two species in competition for a common resource. By a proper choice of the kernel functions, we transfer our model into a coupled localized differential system and shed a new light on how to determine the wave speed sign. Suffcient conditions with symmetry are obtained on the propagation directions of the wavefronts. This symmetry is further verified in the final analysis and numerical simulations are provided to illustrate our theoretical results. [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]

The use of remote camera traps has accelerated rapidly in the field of large carnivore science since the 1990s. Members of the Hyaenidae are important components of functional ecosystems in Africa and parts of the Middle East and South Asia, and make good candidates for study using camera traps. However, camera trap studies of hyenas remain rare in the literature when compared to species like tigers Panthera tigris, leopards Panthera pardus, and snow leopards Panthera uncia. In this paper, we examine the published use of camera traps for hyenas (n = 34 studies implemented between 2007 and 2020) and examine the logistical challenges of using camera traps, such as individual identification, limited sexual dimorphism, and complex social structures, for studies of hyena population biology, behavioral ecology, and conservation. We highlight what these challenges may mean for data analyses and interpretation. We also suggest potential benefits of further camera trap studies of this taxonomic family, including new insights into social behavior, range extensions, and robust density estimates. [ABSTRACT FROM AUTHOR]

Ehrlich received his PhD in 1957 and throughout their life, he and Anne have jointly published many books and papers. Now in his early nineties, the world-renowned biologist Paul R. Ehrlich has published a fascinating and well-illustrated memoir that should be of interest to the public in general, as well as anyone involved in scientific research, including undergraduate and graduate students and their mentors. Ehrlich has "found that being a has-been is much more fun than being a wannabe" (p. 323), and discusses the toils of old age and his and Anne's life in a retirement community. [Extracted from the article]

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]

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]

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]

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]

The energy return on energy invested, EROI or EROEI, is the ratio of the energy produced by a system to the energy expended to build, maintain, and finally dismantle the system. It is an important parameter for evaluating the efficiency of energy-producing technologies. In this paper, we examine the concept of EROEI from the general viewpoint of dynamic dissipative systems, providing insights on a wider range of applications. In general, natural resources can be assimilated to energy stocks characterized by a potential that can be exploited by creating intermediate stocks. This transformation is typical of dissipative systems and for the first time, we report that the Lotka–Volterra model, usually confined to the study of the biology of populations, can represent a powerful tool to estimate the EROEI of dissipative systems and, in particular, those systems subjected to depletion. This assessment is important to evaluate the ongoing energy transition since it provides us with a model for the decline of the EROEI in the exploitation of fossil fuels. [ABSTRACT FROM AUTHOR]

Context: Rusa deer (Cervus timorensis), originally introduced in the 1860s, are still spreading in eastern Australia. The expanding peri-urban rusa deer population in the Illawarra region of New South Wales, Australia is having undesirable impacts on human and ecological communities, but the spatial structure of this population has not been investigated. Genetic information on invasive species is potentially useful in identifying management units to mitigate undesirable impacts. Aims: The aim of this study was to investigate population structure, characterise dispersal, and determine if natural and human-made landscape features affected gene flow in rusa deer invading the Illawarra region of New South Wales. Methods: We used reduced representation sequencing (DArT-Seq) to analyse single nucleotide polymorphisms distributed throughout the genomic DNA of rusa deer culled during a management program. We used admixture and Principal Component Analyses to investigate population structure with respect to natural and human-made landscape features, and we investigated whether our genetic data supported the presence of sex-biased dispersal. Key results: Genetic diversity was highest in the north, near the original introduction site. A railway line demarcated restricted gene flow. Surprisingly, the Illawarra escarpment, a prominent landscape feature, did not restrict gene flow. There was no evidence of sex-biased dispersal and seven individuals were identified as genetic outliers. Conclusions: The genetic structure of the Illawarra rusa deer population is consistent with individuals spreading south from their introduction site in Royal National Park. The population is not panmictic, and a landscape feature associated with urbanisation was associated with increased spatial genetic structure. Outliers could indicate hybridisation or secondary incursion events. Implications: Rusa deer can be expected to continue invading southwards in the Illawarra region, but landscape features associated with urbanisation might reduce dispersal across the landscape. The genetic structuring of the population identified three potential management units on which to prioritise ground shooting operations. Understanding spatial structure is important for the management of invasive deer populations. We sequenced DNA from invasive rusa deer culled during a management program in the Illawarra region, New South Wales, Australia. Genetic diversity decreased from north (the original introduction site) to south, and we identified three spatially distinct units for managing rusa deer in the Illawarra region. Photograph by Scarlett Li-Williams. [ABSTRACT FROM AUTHOR]

The encroachment of woody plants into grasslands is a global phenomenon with implications for biodiversity and ecosystem function. Understanding and predicting the pace of expansion and the underlying processes that control it are key challenges in the study and management of woody encroachment. Theory from spatial population biology predicts that the occurrence and speed of expansion should depend sensitively on the nature of conspecific density dependence. If fitness is maximized at the low‐density encroachment edge, then shrub expansion should be "pulled" forward. However, encroaching shrubs have been shown to exhibit positive feedbacks, whereby shrub establishment modifies the environment in ways that facilitate further shrub recruitment and survival. In this case there may be a fitness cost to shrubs at low density causing expansion to be "pushed" from behind the leading edge. We studied the spatial dynamics of creosotebush (Larrea tridentata), which has a history of encroachment into Chihuahuan Desert grasslands over the past century. We used demographic data from observational censuses and seedling transplant experiments to test the strength and direction of density dependence in shrub fitness along a gradient of shrub density at the grass–shrub ecotone. We also used seed‐drop experiments and wind data to construct a mechanistic seed‐dispersal kernel, then connected demography and dispersal data within a spatial integral projection model (SIPM) to predict the dynamics of shrub expansion. Contrary to expectations based on potential for positive feedbacks, the shrub encroachment wave is "pulled" by maximum fitness at the low‐density front. However, the predicted pace of expansion was strikingly slow (ca. 8 cm/year), and this prediction was supported by independent resurveys of the ecotone showing little to no change in the spatial extent of shrub cover over 12 years. Encroachment speed was acutely sensitive to seedling recruitment, suggesting that this population may be primed for pulses of expansion under conditions that are favorable for recruitment. Our integration of observations, experiments, and modeling reveals not only that this ecotone is effectively stalled under current conditions but also why that is so and how that may change as the environment changes. [ABSTRACT FROM AUTHOR]

The definition and description of the dynamics of a predator-prey system are some of the fundamental problems of population biology. Since 1925, several models have been introduced. Although they are highly effective, most of them neglect certain relevant criteria such as the spatial and temporal distribution of the studied species. We introduced these criteria by coupling two models designed initially for collective dynamics. The first is for predator mobility and is a Vicsek-type model, and the second is a Brownian particle (BP) model for prey. We observed, as occurs in the classical models, periodic cycles of the densities of predators and prey. In this case, the period of oscillations depends on the collective dynamics parameters. [ABSTRACT FROM AUTHOR]

Global levels of biodiversity and dietary diversity are decreasing, leading to food and nutrition insecurity. This is partially due to the homogenization of the global food supply with commodity crops. The reintroduction or introduction of neglected and underutilized species, minor, forgotten, and indigenous crops and landrace varieties to the wider food systems and further diversification have been outlined as the future strategies for tackling the above by the United Nations and the Food and Agriculture Organization in their policy frameworks. Most of the above species/crops are marginalized and only used across local food systems and in research. With over 15,000 different seed banks and repositories worldwide, information transparency and communication are crucial for database searching and their effective utilization. Much confusion persists around the true nature of those plants, and this prohibits the efficient utilization of their economic potential. A linguistic corpus search and a systematic literature review were conducted using the six most popular collocates to the above terms, which were as follows: ancient, heirloom, heritage, traditional, orphan, and the more distinct term 'landrace'. The results were interpreted using the Critical Discourse Analysis method. The definitions' findings show that heirloom, heritage, and ancient are mainly used in the United Kingdom and USA, where they are used to describe 'naturalized' and 'indigenized' or 'indigenous' food crops with a strong affiliation to 'family' and the 'act of passing seeds down from generation to generation'. Orphan crops, on the other hand, are often described as being 'overlooked' by growers and 'underfunded' by researchers. Landrace is most strongly affiliated with 'locality', 'biocultural diversity', and 'indigenous', and with genomics literature, where the characteristics are often discussed in the context of genetics and population biology. Contextualizing, most of the terms were found to be 'arbitrary' and 'undefinable' due to their continuing evolution in the socially accepted form of language, perhaps apart from landrace. The review has retrieved 58 definitions for the mentioned 6 terms, together with the primary key terms creating a tool to facilitate a better inter-sector communication and aid in policy. [ABSTRACT FROM AUTHOR]

This review is about statistical genetics, an interdisciplinary topic between statistical physics and population biology. The focus is on the phase of quasi-linkage equilibrium (QLE). Our goals here are to clarify under which conditions the QLE phase can be expected to hold in population biology and how the stability of the QLE phase is lost. The QLE state, which has many similarities to a thermal equilibrium state in statistical mechanics, was discovered by M Kimura for a two-locus two-allele model, and was extended and generalized to the global genome scale by Neher & Shraiman (2011). What we will refer to as the Kimura–Neher–Shraiman theory describes a population evolving due to the mutations, recombination, natural selection and possibly genetic drift. A QLE phase exists at sufficiently high recombination rate (r) and/or mutation rates µ with respect to selection strength. We show how in QLE it is possible to infer the epistatic parameters of the fitness function from the knowledge of the (dynamical) distribution of genotypes in a population. We further consider the breakdown of the QLE regime for high enough selection strength. We review recent results for the selection-mutation and selection-recombination dynamics. Finally, we identify and characterize a new phase which we call the non-random coexistence where variability persists in the population without either fixating or disappearing. [ABSTRACT FROM AUTHOR]

Our understanding of the interplay between skin microbiota and the skin's health status is growing. Consequently, the cosmetics industry is increasingly concerned with ensuring that beauty products do not adversely affect this microbiota and skin health. Prior to implementing demanding sequencing-based analyses of skin microbiota, an agile approach is needed to provide a first estimate of the short-term impact of cosmetic ingredients on the viability of skin microbiota. A standardized methodology, including topical applications, swabbing, and bacterial colony-counting, was set up and evaluated. The skin's bacterial density was longitudinally monitored after repeated applications of two reference compounds: physiological saline, assumed to be neutral, and chlorhexidine, expected to have a perturbing effect. Healthy volunteers were enrolled in six clinical studies, involving application of physiological saline and chlorhexidine to both sides of the neck. Over 7 days, skin swabs were collected at defined time points, and bacterial density was assessed based on a classical colony-counting approach. The longitudinal assessment of skin bacterial density proved highly robust, with a very steady inter-seasonal impact of chlorhexidine on skin bacterial density. This consolidated methodology supported the development of an easy-to-understand viability score that quantifies the intrinsic short-term impact of an ingredient on skin bacterial populations. [ABSTRACT FROM AUTHOR]

Copyright of Ginecología y Obstetricia de México is the property of Federacion Mexicana de Ginecologia y Obstetricia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Variations in the reproductive and survival abilities of individuals within a population are ubiquitous in nature, key to individual fitness, and affect population dynamics, which leads to strong interest in understanding causes and consequences of vital‐rate variation. For long‐lived species, long‐term studies of large samples of known‐age individuals are ideal for evaluating vital‐rate variation.A population of Weddell seals in Erebus Bay, Antarctica, has been studied each Austral spring since the 1960s. Since 1982, all newborns have been tagged each year and multiple capture‐mark‐recapture (CMR) surveys have been conducted annually.Over the past 20 years, a series of analyses have built on results of earlier research by taking advantage of steady improvements in the project's long‐term CMR data and available analytical methods. Here, I summarize progress made on four major topics related to variation in age‐specific vital rates for females: early‐life survival and age at first reproduction, costs of reproduction, demographic buffering, and demographic senescence.Multistate modelling found that age at first reproduction varies widely (4–14 years of age) and identified contrasting influences of maternal age on survival and recruitment rates of offspring. Subsequent analyses of data for females after recruitment revealed costs of reproduction to both survival and future reproduction and provided strong evidence of demographic buffering. Recent results indicated that important levels of among‐individual variation exist in vital rates and revealed contrasting patterns for senescence in reproduction and survival.Sources of variation in vital rates include age, reproductive state, year, and individual. The combination of luck and individual quality results in strong variation in individual fitness outcomes: ~80% of females born in the population produce no offspring, and the remaining 20% vary strongly in lifetime reproductive output (range: 1–23 pups).Further research is needed to identify the specific environmental conditions that lead to annual variation in vital rates and to better understand the origins of individual heterogeneity. Work is also needed to better quantify the relative roles of luck, maternal effects, and environmental conditions on variation in vital rates and to learn the importance of such variation to demographic performance of offspring and on overall population dynamics. [ABSTRACT FROM AUTHOR]

Narrowly endemic species are particularly vulnerable to catastrophic events. Compared to widespread species, they may also be less capable of adapting to shifts in environmental pressures as a result of specialisation on a narrow range of local condition and limited ability to disperse. However, life-history traits, such as preferential outcrossing and high fecundity can maintain genetic diversity and evolutionary potential, and boost species resilience. The endangered Grevillea bedggoodiana (Enfield Grevillea) is an understorey shrub restricted to an area of ca. 150 km2 in south-eastern Australia with a legacy of large-scale anthropogenic disturbance. Prior to this study little was known about its biology and population structure. Here, its breeding system was assessed through a controlled pollination experiment at one of its central populations, and eight populations were sampled for genetic analysis with microsatellite markers. The species was found to be preferentially outcrossing, with no evidence of pollination limitation. In most populations, allelic richness, observed heterozygosity and gene diversity were high (Ar: 3.8–6.3; Ho: 0.45–0.65, He: 0.60 − 0.75). However, the inbreeding coefficients were significant in at least four populations, ranging from Fi -0.061 to 0.259 despite high outcrossing rates. Estimated reproductive rates varied among sampled populations but were independent of gene diversity and inbreeding. Despite its small geographic range, the species' populations showed moderate differentiation (AMOVA: FST = 0.123), which was largely attributable to isolation by distance. We interpret these results as suggesting that G. bedggoodiana is reproductively healthy and has maintained high levels of genetic diversity despite recent disturbance. [ABSTRACT FROM AUTHOR]

Copyright of Parasite (1252607X) is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Gastrointestinal nematodes (GIN) are amongst the most important pathogens of grazing ruminants worldwide, resulting in negative impacts on cattle health and production. The dynamics of infection are driven in large part by the influence of climate and weather on free-living stages on pasture, and computer models have been developed to predict infective larval abundance and guide management strategies. Significant uncertainties around key model parameters limits effective application of these models to GIN in cattle, however, and these parameters are difficult to estimate in natural populations of mixed GIN species. In this paper, recent advances in molecular biology, specifically ITS-2 rDNA 'nemabiome' metabarcoding, are synthesised with a modern population dynamic model, GLOWORM-FL, to overcome this limitation. Experiments under controlled conditions were used to estimate rainfall constraints on migration of infective L3 larvae out of faeces, and their survival in faeces and soil across a temperature gradient, with nemabiome metabarcoding data permitting species-specific estimates for Ostertagia ostertagi and Cooperia oncophora in mixed natural populations. Results showed that L3 of both species survived well in faeces and soil between 0 and 30 °C, and required at least 5 mm of rainfall daily to migrate out of faeces, with the proportion migrating increasing with the amount of rainfall. These estimates were applied within the model using weather and grazing data and use to predict patterns of larval availability on pasture on three commercial beef farms in western Canada. The model performed well overall in predicting the observed seasonal patterns but some discrepancies were evident which should guide further iterative improvements in model development and field methods. The model was also applied to illustrate its use in exploring differences in predicted seasonal transmission patterns in different regions. Such predictive modelling can help inform evidence-based parasite control strategies which are increasingly needed due climate change and drug resistance. The work presented here also illustrates the added value of combining molecular biology and population dynamics to advance predictive understanding of parasite infections. • Nemabiome sequencing was combined with modelling nematode populations. • Models were adapted for Ostertagia ostertagi and Cooperia oncophora in N.America. • Updated life-history parameters were defined based on in vitro observations. • The refined model can effectively predict the seasonal patterns of cattle GIN. [ABSTRACT FROM AUTHOR]