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The apparent virilization of the female spotted hyena raises questions about sex differences in behavior and morphology. We review these sex differences to find a mosaic of dimorphic traits, some of which conform to mammalian norms. These include space-use, dispersal behavior, sexual behavior, and parental behavior. By contrast, sex differences are reversed from mammalian norms in the hyena's aggressive behavior, social dominance, and territory defense. Androgen exposure early in development appears to enhance aggressiveness in female hyenas. Weapons, hunting behavior, and neonatal body mass do not differ between males and females, but females are slightly larger than males as adults. Sex differences in the hyena's nervous system are relatively subtle. Overall, it appears that the "masculinized" behavioral traits in female spotted hyenas are those, such as aggression, that are essential to ensuring consistent access to food; food critically limits female reproductive success in this species because female spotted hyenas have the highest energetic investment per litter of any mammalian carnivore. Evidently, natural selection has acted to modify traits related to food access, but has left intact those traits that are unrelated to acquiring food, such that they conform to patterns of sexual dimorphism in other mammals.

Introduction: The curve of spee plays an important role to create Christensen’s phenomenon in natural dentition. This study was performed to assess the difference in depth of the curve of Spee between normal and attrited dentition. Methods: An analytical cross-sectional study was performed to measure the depth of curve speed in a total of 80 willing participants who met the inclusion criteria, of which 40 had normal dentition and 40 had attrited dentition. Measurements were done on stone casts by using a rigid metal scale and a digital vernier caliper. Analytical statistical analysis (independent t-test) was done using SPSS Statistical Software Package (version 21.0). Results: There was a statistically significant difference in the depth of the curve of Spee between the two groups. Conclusions: The depth of the curve of spee decreases with the advancing of the age of human as attrition of the teeth occurs with age. Although there is a decrease in the depth of the curve of spee it should be maintained and created while performing full mouth rehabilitation and other extensive prosthodontic treatments.

Different reproductive modes are characterized by costs and benefits which often depend on ecological contexts. Benefits of sex are expected to increase under complex biotic interactions, whereas parthenogenesis can be beneficial for reproductive assurance when females are mate limited. Here, we study how different ecological contexts influence the frequency of sex or parthenogenesis in the facultatively parthenogenetic mayfly Alainites muticus. We first verified that high parthenogenetic frequencies translate into female-biased population sex ratios. We then measured the population sex ratio (a proxy for parthenogenetic capacities), density of individuals (mate limitation) and community diversity (biotic interaction complexity) for 159 A. muticus populations, and used structural equation modeling to investigate their direct and indirect influences on sex ratios. We found no effect of community diversity or altitude on sex ratios. Furthermore, even when females can reproduce parthenogenetically, they generally reproduce sexually, indicating that the benefits of sex exceed its costs in most situations. Sex ratios become female-biased in low population densities, as expected if mate limitation selects for parthenogenesis. Mate limitation might be widespread in mayflies because of their very short adult lifespan and limited dispersal, which can generate strong selection for reproductive assurance and may provide a steppingstone towards obligate parthenogenesis.

The present study reports the seed dispersal modes of tree species and their relationship with altitudinal gradient from six tropical forests of Eastern Ghats located in India. Anemochory, autochory and zoochory are the three major types of seed dispersal modes recognized for the 272 tree species recorded from a total of 120 0.5 ha area. The predominant dispersal mode is zoochory with 58% of the total tree abundance and 69% of total species richness, followed by autochory with 30% and 19%, and anemochory 12% and 12%, respectively. One way ANOVA revealed that the species richness as well as tree abundance of the three dispersal modes varied significantly across the six tropical forest sites. Regression analysis revealed that both the tree species richness and abundance of zoochory dispersal mode had positive relation with altitude of forest location, while, no such relation was observed for the other two dispersal modes. This study shows that the zoochory increases in species richness and tree abundance with increasing altitude. This may be attributed to high rainfall supporting evergreen forest types with high ratio of animal dispersed tree species in forests at high altitude. However, further studies on these aspects are warranted to draw a significant statement. The predomination of zoochory dispersal mode in this study is comparable with earlier studies in tropical forests elsewhere.

Understanding the factors that allow a species to expand its range and adapt to changing habitats is essential for mitigating anthropogenic change. We evaluated how behavior and cognition facilitate colonization of new environments and evolve post establishment during natural biological invasions. Marine threespined sticklebacks are expert colonists with a penchant for invading freshwater environments and rapidly adapting to them. However, the role of behavior in facilitating rapid adaptation in this system has received little attention. By rearing replicate populations of sticklebacks under common garden conditions in the lab, we tested the hypothesis that boldness is favored in dispersers and that neophilia and flexibility are favored in recently-arrived immigrants. We found that dispersing populations comprised bold individuals, while sticklebacks from the invaded region were flexible in their behavior. Moreover, boldness and flexibility were negatively correlated with each another at the individual, family and population levels. Multiple lines of evidence suggest that there is a heritable component to boldness and flexibility, therefore their divergence is likely to be evolutionary in origin. If boldness is favored in invaders during the initial dispersal stage, while flexibility is favored in recent immigrants during the establishment stage, then the link between boldness and flexibility could generate positive correlations between successes during both the dispersal and establishment stages, and therefore play a key role in facilitating colonization success in this important model organism. SIGNIFICANCE STATEMENTFor a species to expand its range, it needs to be good at dispersing and also capable of exploiting resources and adapting to different environments. Therefore, behavioral and cognitive traits such as boldness, neophilia and behavioral flexibility could play key roles in facilitating invasion success. Here, we show that dispersing sticklebacks are bold, while sticklebacks that have recently established in a new region are flexible. Moreover, boldness and flexibility are negatively correlated with one another. If boldness is favored in dispersers while flexibility is favored in immigrants, then this behavioral syndrome could play a heretofore underappreciated role in facilitating rapid adaptation in this important model organism.

A Late Cretaceous fossil flora composed of five fossil seed genera and two charophyte genera was discovered and reported here from the siltstone and green marl band of the Lameta Formation at the Chui Hill section and the Chhota Simla Hill section in the Jabalpur area. On the basis of comparative studies, including thin-section and XRD analysis, the palaeoenvironment is deduced to be arid to semi-arid fluvial-lacustrine. The recovered flora suggests Laurasian palaeobiogeographic affinity and shows the dispersal route from Europe to India via Africa.

Even when environments deteriorate gradually, ecosystems may shift abruptly from one state to another. Such catastrophic shifts are difficult to predict and reverse (hysteresis). While well studied in simplified contexts, we lack a general understanding of how catastrophic shifts spread in realistic spatial contexts. For different types of landscape structure, including typical terrestrial modular and riverine dendritic networks, we here investigate landscape-scale stability in metapopulations made of bistable patches. We find that such metapopulations usually exhibit large scale catastrophic shifts and hysteresis, and that the properties of these shifts depend strongly on metapopulation spatial structure and dispersal rate: intermediate dispersal rates and a riverine spatial structure can largely reduce hysteresis size. Interestingly, our study suggests that large-scale restoration is easier with spatially clustered restoration efforts and in populations characterized by an intermediate dispersal rate.

Indian Railways has one of the most extensive rail systems in the world which covers 68,000 km of rail track, 7318 stations with over 23 million passengers daily. This public transport system is one of the cheapest modes of travel for millions of Indians daily. With such an extensive system in place, railways need to maintain an efficient infrastructure system; it is expected passengers handling to reach 15.20 Billion by FY20, passenger traffic is noted to grow by 1.69 percent year on year. With such a kind of growth in patronage, it profoundly impacts the existing infrastructure. Thus, a constant upgrade is required in infrastructure. This research study focuses on NSG-1 (Non – Suburban Stations) taking New Delhi station as a case study. The research study is based on the level of service for access and dispersal facilities of the passengers. This paper will analyze the optimum level of service for passengers based on their behavior in a terminal building. This study identifies Equivalent Passenger Units (EPU’s) from passenger behavior and anthropometric studies. EPU’s further is used to evaluate the level of services for the passenger's mobility in the terminal building. Access and Dispersal facilities have been studied for the case study station, and influence zones are created for the same. The outcome of the study is the space assessment. The methodology can be used to identify the optimum level of services for different categories of the railway station. The space planning norms can be generated and then can be used by consultants for efficient planning of brownfield and greenfield stations at the optimum design service level.

Dispersal and shared environmental conditions can both synchronize the dynamics of local populations, but disentangling their relative influence on dynamics is challenging. We used a Bayesian approach to estimate the synchrony of a metapopulation of Atlantic salmon (Salmo salar) composed of 18 populations in Brittany, France, including a 24-year time series of the abundances of juveniles. We estimated the spatial synchrony at a regional and local spatial scale over the study period. We found a strong regional synchrony despite spatiotemporal variability of local synchrony in the abundance of juveniles. We then explored the drivers of synchrony, including environmental conditions (aspects of river flow) and abundance of adult breeders. This revealed that summer low-flow conditions seemed to synchronize the abundances of juveniles more than the synchrony in the abundance of adult breeders, suggesting a Moran effect. Given that drought conditions are expected to become more common with climate change, our work highlights the potentially strong synchronizing effect of summer low flow on the dynamics of local salmon populations and the benefits of considering synchrony at multiple scales.

As one of the most well-documented biogeographic patterns, the distance-decay relationship provides insights into the underlying mechanisms driving biodiversity distribution. Although wastewater treatment plants (WWTPs) are well-controlled engineered ecosystems, this pattern has been seen among microbial communities in activated sludge (AS). However, little is known about the relative importance of environmental heterogeneity and dispersal limitation in shaping AS microbial community across China; especially they are related to spatial scale and organism types. Here, we assessed the distance-decay relationship based on different spatial scales and microbial phylogenetic groups by analyzing 132 activated sludge (AS) samples across China comprising 3,379,200 16S rRNA sequences. Our results indicated that the drivers of distance-decay pattern in China were scale-dependent. Microbial biogeographic patterns in WWTPs were mainly driven by dispersal limitation at both local and national scales. In contrast, conductivity, SRT, and pH played dominant roles in shaping AS microbial community compositions at the regional scale. Turnover rates and the drivers of beta-diversity also varied with microorganism populations. Moreover, a quantitative relationship between dispersal limitation ratio and AS microbial turnover rate was generated. Collectively, these results highlighted the importance of considering multiple spatial scales and micro-organism types for understanding microbial biogeography in WWTPs and provided new insights into predicting variations in AS community structure in response to environmental disturbance.

France displays a latitudinal range for the expansion of Aedes albopictus invasive populations that is not yet completely colonized providing a critical opportunity to address key invasion processes. We propose a spatio-temporal model (DISTIGRI) to describe and predict current and future expansion at both intra- and inter-annual scales of A. albopictus. This process-based model integrates mechanistic descriptions of the developmental cycle and the dispersal process of A. albopictus within a reaction-diffusion framework, depending on climatic suitability and photoperiod with a high spatio-temporal resolution. Using this model coupled with a climatic database, we propose several maps describing the current intra-annual distribution of A. albopictus, including the date of first emergence and the length of the period with significant adult presence. We also compute its future distribution over the next 10 years under several climatic scenarios, which shows a range expansion with a strong dependence on the climatic scenario. The outputs of the model may constitute a valuable asset for designing control and avoidance strategies, and to anticipate the biting nuisance with a high spatio-temporal resolution. These outputs also emphasize the importance of taking both dispersal and life cycle into account to obtain accurate descriptions of out-of-equilibrium processes such as ongoing invasions.

Dispersal propensity has been correlated with personality traits, conspecific density and predation risk in a variety of species. Thus, changes in the relative frequency of behavioural phenotypes or in the ecological pressures faced by individuals in contrasting habitats can have unexpected effects on their dispersal strategies. Here, using the burrowing owl Athene cunicularia as a study model, we test whether changes in the behavioural profile of individuals and changes in conspecific density and predation pressure associated with urban life influence their breeding dispersal decisions compared to rural conspecifics. Our results show that breeding dispersal behaviour differs between rural and urban individuals. Site fidelity was lower among rural than among urban birds, and primarily related to an individual's behaviours (fear of humans), which has been reported to reflect individual personality. In contrast, the main determinant of site fidelity among urban owls was conspecific density. After taking the decision of dispersing, urban owls moved shorter distances than rural ones, with females dispersing farther than males. Our results support a personality-dependent dispersal pattern that might vary with predation risk. However, as multiple individuals of two populations (one urban, one rural) were used for this research, differences can thus also be caused by other factors differing between the two populations. Further research is needed to properly understand the ecological and evolutionary consequences of changes in dispersal behaviours, especially in terms of population structuring and gene flow between urban and rural populations.

Recent archaeological discoveries suggest that both archaic Denisovans and Homo sapiens occupied the Tibetan Plateau earlier than expected. Genetic studies show that a pulse of Denisovan introgression was involved in the adaptation of Tibetan populations to high-altitude hypoxia. These findings challenge the traditional view that the plateau was one of the last places on earth colonized by H. sapiens and warrant a reappraisal of the population history of this highland. Here, we integrate archaeological and genomic evidence relevant to human dispersal, settlement, and adaptation in the region. We propose two testable models to address the peopling of the plateau in the broader context of H. sapiens dispersal and their encounters with Denisovans in Asia.

Key message Grain disarticulation in wild progenitor of wheat and barley evolved through a local duplication event followed by neo-functionalization resulting from changes in location of gene expression. Abstract One of the most critical events in the process of cereal domestication was the loss of the natural mode of grain dispersal. Grain dispersal in barley is controlled by two major genes, Btr1 and Btr2, which affect the thickness of cell walls around the disarticulation zone. The barley genome also encodes Btr1-like and Btr2-like genes, which have been shown to be the ancestral copies. While Btr and Btr-like genes are non-redundant, the biological function of Btr-like genes is unknown. We explored the potential biological role of the Btr-like genes by surveying their expression profile across 212 publicly available transcriptome datasets representing diverse organs, developmental stages and stress conditions. We found that Btr1-like and Btr2-like are expressed exclusively in immature anther samples throughout Prophase I of meiosis within the meiocyte. The similar and restricted expression profile of these two genes suggests they are involved in a common biological function. Further analysis revealed 141 genes co-expressed with Btr1-like and 122 genes co-expressed with Btr2-like, with 105 genes in common, supporting Btr-like genes involvement in a shared molecular pathway. We hypothesize that the Btr-like genes play a crucial role in pollen development by facilitating the formation of the callose wall around the meiocyte or in the secretion of callase by the tapetum. Our data suggest that Btr genes retained an ancestral function in cell wall modification and gained a new role in grain dispersal due to changes in their spatial expression becoming spike specific after gene duplication.

Capacity for dispersal is a fundamental fitness component of plant pathogens. Characterization of plant pathogen dispersal is important for understanding how pathogen populations change in time and space. We devised a systematic approach to measure and analyze rain splash-driven dispersal of plant pathogens in field conditions, using the major fungal wheat pathogen Zymoseptoria tritici as a case study. We inoculated field plots of wheat ( Triticum aestivum) with two distinct Z. tritici strains. Next, we measured disease intensity as counts of fruiting bodies (pycnidia) using automated image analysis. These measurements characterized primary disease gradients, which we used to estimate effective dispersal of the pathogen population. Genotyping of reisolated pathogen strains with strain-specific PCR confirmed the conclusions drawn from phenotypic data. Consistently with controlled environment studies, we found that the characteristic scale of dispersal is tens of centimeters. We analyzed the data using a spatially explicit mathematical model that incorporates the spatial extent of the source, rather than assuming a point source, which allows for a more accurate estimation of dispersal kernels. We employed bootstrapping methods for statistical testing and adopted a two-dimensional hypotheses test based on kernel density estimation, enabling more robust inference compared with standard methods. We report the first estimates of dispersal kernels of the pathogen in field conditions. However, repeating the experiment in other environments would lead to more robust conclusions. We put forward advanced methodology that paves the way for further measurements of plant pathogen dispersal in field conditions, which can inform spatially targeted plant disease management. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

PREMISE OF THE STUDY Continental-scale disjunctions and associated drivers is a core research interest in biogeographic studies. Here, we selected a species-rich Australian plant genus (Calytrix; Myrtaceae) as a case study to investigate these patterns. The endemic Australian starflower genus has a disjunct distribution across the mesic fringes of the continent and is largely absent from the arid centre. METHODS We used high-throughput sequencing to generate unprecedented resolution and near complete species-level nuclear and plastid phylogenies for Calytrix. BioGeoBEARS and biogeographic stochastic mapping were used to infer ancestral areas, the relative contributions of vicariance and dispersal events, and directionality of dispersal. KEY RESULTS Present-day disjunctions in Calytrix are explained by a combination of scenarios: (1) retreat of multiple lineages from the continental centre to the more mesic fringes as Australia became progressively more arid, with subsequent extinction in the centre, and also (2) origination of ancestral lineages in southwestern Australia (SWA) for species-rich clades. The SWA biodiversity hotspot is a major diversification centre and the most common source area of dispersals, with multiple lineages originating in SWA and subsequently spreading to the adjacent arid Eremaean region. CONCLUSIONS Our results suggest major extinction, as a result of cooling and drying of the Australian continent in the Eocene-Miocene, shaped the present-day biogeography of Calytrix. We hypothesise that this peripheral vicariance pattern, which is similar to the African Rand flora, may explain the disjunctions of many other Australian plant groups. Further studies with densely sampled phylogenies are required to test this hypothesis. This article is protected by copyright. All rights reserved.

During the Late Iron Age, early Nguni-speaking farmers entered and moved across the region of the lower Thukela uplands through frequent, short-range episodes of population movement. As they did so, they innovated new food production technology, altered the landscape, and adapted to ecological conditions. The article presents comparative historical linguistic evidence for the history of farming and interaction with the environment among Nguni-speakers between c. 900–1052 CE. Analysis shows the ways Nguni-speaking farmers responded to environmental conditions through landscape engineering and social engineering, including population dispersal.

Specimens of the genus Megantereon from younger strata (late Early Pleistocene to Middle Pleistocene) in China are reviewed in the presented work. The specimens found in Linyi, Shanxi Province, which were previously identified as Megantereon nihowanensis, have been reexamined and their identity has been revised to be Megantereon inexpectatus. With respect to the new specimens of M. inexpectatus found in the Jinyuan Cave, Dalian, Liaoning Province, the identification of the mandible specimen from the Gongwangling Homo site, which was named as a new species, Megantereon lantianensis, has been revised to M. inexpectatus. Known records of M. inexpectatus have been reported in Linyi, Shanxi, and Lantian, Shaanxi Province, in older deposits from the late Early Pleistocene, and younger deposits from the Middle Pleistocene in Zhoukoudian, Beijing. In morphological comparisons and phylogenetic discussions, the best candidate origin of M. inexpectatus is Africa, where a relatively advanced lineage gave rise to M. inexpectatus and its relative Megantereon whitei. A significant dispersal event of M. inexpectatus occurred during the late Early Pleistocene, represented by the immigration of M. whitei from Africa to Europe and the occurrence of M. inexpectatus in Asia. There is no evidence indicating that this biotic event was initiated by environmental change, with survival pressure from hominins likely to have been the main factor that forced Megantereon to migrate into Eurasia.

We conducted a biogeographic analysis of the PPAM clade of Poeae Plastid DNA Group 2, which includes 12 subtribes of C-3 grasses. One hundred and eighty-four species sampled represent 42 of 43 accepted genera and taxonomic diversity in large genera. We analyzed plastid sequences of matK, trnC-rpoB, and trnT-trnL-trnF using BEAST to produce a dated tree and MrBayes to produce a Bayesian tree, on which we ran Bayesian-Binary-Markov-Chain analyses on a worldwide biogeographic data set of 12 areas. PPAM split in southwestern Asia into subtribe Coleanthinae and PAM clades in the Early Miocene. PAM diversified rapidly in the Middle Miocene in southwestern Asia into four monogeneric lineages, Avenulinae, Phleinae, Miliinae, Poinae, and the Alopecurinae superclade (seven subtribes with 27 genera). In the Late Miocene, Pliocene, and mostly Pleistocene, the latter four lineages diversified and dispersed across Eurasia and established in North America. Dispersals to the southern hemisphere occurred in the Pliocene and Pleistocene. Annuals occur in 15 Mediterranean and southwestern Asia genera, but in few genera in other regions. Beyond phylogenetically isolated annual species dating to the Miocene, all other annuals evolved in the Pliocene and Pleistocene. Cold tolerance is high among perennial species, many occurring in the alpine, nine genera ranging into the Arctic. We suggest that alpine and subalpine habitats were ancestral. High tolerance of saline and alkaline conditions arose between the Pliocene and Pleistocene in Coleanthinae, Alopecurinae, Poinae, Hookerochloinae, Beckmanniinae, and Arctopoa. Combinations are proposed for Cornucopiae alopecuroides in Alopecurus and for Paracolpodium colchicum in Hyalopodium. A nothogenus x Catanellia is proposed for Catabrosa x Puccinellia.

Epibenthic invertebrate assemblages in macroalgal beds generally show remarkable seasonal fluctuations in abundance and species composition, reflecting macroalgal host growth and defoliation. Notably, they often drastically decrease during macroalgal host defoliation. Though this reduction has been explained in terms of dispersal away from the macroalgal bed in relation to macroalgal host defoliation, this hypothesis has not previously been experimentally detailed. We conducted a field experiment using an imitation of Sargassum that was set 1 m away from a Sargassum yezoense bed to examine whether the epibenthic gammarids disperse away from the Sargassum bed as a result of Sargassum defoliation. The imitations were replaced monthly throughout the Sargassum defoliation season; subsequently, gammarids associated with the imitation (assumed as migrants from the Sargassum beds) as well as the gammarids that occurred in the Sargassum bed were investigated. Seasonal patterns of gammarid abundance in the Sargassum bed and their dispersal to the imitations were found to be quite different among gammarid species. In particular, 2 dominant gammarids, the suspension-feeding Jassa morinoi and Podocerus sp., drastically decreased in the Sargassum bed and coincidently increased in the imitations during the Sargassum defoliation season, indicating their defoliation-associated dispersal from the Sargassum bed. This is the first field experimental study demonstrating the defoliation-associated dispersal of epibenthic invertebrates in macroalgal beds. The dispersal is likely caused by a reduction of habitat space and quality due to thalli defoliation. Since many macroalgae show seasonal growth and defoliation, the concept of defoliation-associated dispersal is potentially applicable to various macroalgal species.

Cenozoic tectonic evolution in the Tethyan region has greatly changed the landforms and environment of Eurasia, driving the evolution of animals and greatly affecting the diversity patterns of Eurasian animals. By combining the latest Tethyan paleogeographic models and some recently published Eurasian zoological studies, we systematically summarize how tectonic evolution in the Tethyan region has influenced the evolution and diversity patterns of Eurasian animals. The convergence of continental plates, closure of Tethys Sea, and Tethyan sea-level changes have directly affected the composition and spatial distribution of Eurasian animal diversity. The topographic and environmental changes caused by Tethyan tectonics have determined regional animal diversity in Eurasia by influencing animal origin, dispersal, preservation, diversification, and extinction. The ecological transformations resulted in the emergence of new habitats and niches, which promoted animal adaptive evolution, specialization, speciation, and expansion. We highlight that the Cenozoic tectonic evolution of the Tethyan region has been responsible for much of the alteration in Eurasian animal distribution and has been an essential force in shaping organic evolution. Furthermore, we generalize a general pattern that Tethyan geological events are linked with Eurasian animal evolution and diversity dynamics.特提斯海区域新生代以来的构造演化极大地改变了欧亚地区的地貌和环境，推动了欧亚地区的动物演化，并深刻影响了欧亚地区的动物多样性格局。该文通过结合最新的特提斯海区域古地理模型，对近期发表的一系列欧亚地区动物学研究进行系统回顾和总结，详细论述了特提斯海区域新生代以来的构造演化是如何影响欧亚地区动物的演化及多样性格局的：大陆板块的汇聚、特提斯海的闭合以及特提斯海区域海平面变化直接影响了欧亚地区的动物多样性组成和空间分布；海陆变迁引起的区域地理和环境变化，对当地动物的起源、扩散、存留、多样化和灭绝产生了一系列影响，进而决定了欧亚动物的区域多样性格局；生态环境的变化导致了新栖息地和新生态位的出现，促进了欧亚动物的适应性进化、特化、物种形成和扩张。我们强调了特提斯海区域新生代构造演化是欧亚动物分布变化的主要原因，也是驱动欧亚动物演化的重要力量。此外，我们提出了特提斯地质事件与欧亚动物演化和多样性动态相关的一般模式。.

Prey may gain fitness benefits from recognizing predators at an early age. Predator cues perceived by gravid prey have the potential to prime offspring to alter their behaviour in the presence of predation threats after birth. Wolf spiders (Araneae: Lycosidae) provide an opportunity to explore this phenomenon since females carry their eggsacs prior to eclosion and, after emergence, carry spiderlings for days as they disperse. During maternal care, mothers may prenatally expose offspring to predator odour cues and potentially influence their posteclosion dispersal when in the presence of these cues. Spiderlings of the wolf spider Tigrosa helluo are eaten by adults of the wolf spider Pardosa milvina. We measured differences in substrate preferences of spiderlings produced from egg-carrying T. helluo females that had or had not been exposed to cues of adult P. milvina. Over a 15-day period we counted the number of offspring climbing on substrates previously walked on by P. milvina, crickets or blank control substrates. For the first 10 out of 15 days, spiderlings of predator-exposed mothers climbed on Pardosa substrates significantly more compared to control mothers. We found no significant spiderling preference in time spent on cricket-cued or control substrates across treatments and no difference in chemical cue substrate preference of the mothers while spiderlings dispersed. Among wolf spiders, vertical climbing and contact with predator-cued substrates can induce adaptive tonic immobility (freeze response) that has been associated with increased survival in the presence of live predatory lycosids. Spider predator cues may prime spiderling antipredator behaviour either directly through prenatal exposure in the eggsac or indirectly by modifying the mother's behaviour prior to eclosion, but we found no evidence of mother substrate preference influencing spiderling distribution during dispersal.

Microorganisms have long been isolated from soils to develop microbial inoculants, with the goal of spiking them into new soils to augment target functions. However, establishment can be sporadic, and we assume that inoculants simply arrive at their destination. Here, we posit a need for integrating dispersal into inoculant development and deployment. We argue that consideration for an inoculant's dispersal ability, whether via active (e.g., chemotaxis) or passive (e.g., attachment to other organisms) means, and including methods of deployment that allow multiple establishment attempts could help increase the predictability of inoculant success. Dispersal can influence many key aspects of in-field survival, including the ability to escape stressors, seek favorable colonization sites, facilitate multiple establishment attempts, and engage in multikingdom interactions.

Made available in DSpace on 2022-04-29T08:33:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 The time for flowering and fruiting in plants is mainly influenced by environmental factors. Plant species that are subject to different environmental conditions, but phylogenetically close, such as forest and savanna congeneric species pairs growing in forest-savanna transitions in the Neotropics, can be comparatively studied to isolate the effects of the environment from phylogenetic influences. Thus, we performed a comparative study of flowering and fruiting start and duration, as well its relationships with dispersal modes and canopy phenology, analyzing herbarium data for 25 congeneric species pairs from different families, each containing at least one savanna and one forest species. We examined species phenological patterns using digitized specimens from one of the most comprehensive digitized plant datasets in Brazil, the SpeciesLink. We found savanna species having shorter flowering duration (2–5 months) in comparison with forest (3–8 months) congeneric species. Congeneric pairs presented similar reproductive phenological responses for all other studied traits. We found that dispersal mode played an important role in determining fruiting start and duration, while flowering and fruiting start were explained by leaf deciduousness. Although there were many phenological similarities between savanna and forest species, there were differences in flowering duration between savanna and forest species in some congeneric pairs. Departamento de Engenharia Ambiental Instituto de Ciência e Tecnologia Universidade Estadual Paulista (Unesp) Rodovia Presidente Dutra, Km 137,8, Eugênio de Melo Departamento de Biologia Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista, Via de Acesso Prof. Paulo Donatto Castellane S/N, Vila Industrial Departamento de Engenharia Ambiental Instituto de Ciência e Tecnologia Universidade Estadual Paulista (Unesp) Rodovia Presidente Dutra, Km 137,8, Eugênio de Melo Departamento de Biologia Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista, Via de Acesso Prof. Paulo Donatto Castellane S/N, Vila Industrial

Microorganisms mainly exist in the form of biofilm in nature. Biofilm can contaminate food and drinking water system, as well as cause chronic wound infections, thereby posing a potential threat to public health safety. In the last two decades, researchers have made efforts to investigate the genetic contributors control different stages of biofilm development (adherence, initiation, maturation, and dispersal). As an opportunistic pathogen, C. albicans causes severe superficial or systemic infections with high morbidity and mortality under conditions of immune dysfunction. It has been reported that 80% of C. albicans infections are directly or indirectly associated with biofilm formation on host or abiotic surfaces including indwelling medical devices, resulting in high morbidity and mortality. Significantly, the outcome of C. albicans biofilm development includes enhanced invasion, exacerbated inflammatory responses and intrinsic resistance to antimicrobial chemotherapy. Thus, this review aimed at providing a comprehensive overview of the regulatory network controls microbial biofilm development, with C. albicans as a representative, served as reference for therapeutic targets.

This paper compares quantitative and qualitative results from selected pottery assemblages in sites in the northern Philippines with those from sites in the Mariana Islands. Pottery appears in this region sometime between 4000 and 3000 years ago, with the pottery of the Marianas Islands being towards the younger end of this age range. Arguments concerning the origins of the first pottery in the Marianas have been dominated to date by the correlation of selected decorative and stylistic attributes of the Marianas pottery with that of pottery found in sites in Island Southeast Asia (ISEA). The similarities and differences in the pottery at the assemblage levels, however, have never been fully articulated. Recent arguments regarding the pottery have been specifically focused on perceived parallels between the early Marianas Red pottery and the early pottery of the Cagayan Valley in the northern Philippines. Although it has not been explicitly suggested that the northern Philippines was the immediate departure point for migrant boats, it has nevertheless been argued that there are more parallels between the pottery assemblages of these two regions than any others. This has even been a contributing factor in recent revisions to the Out of Taiwan model, which concerns the migration and dispersal of Austronesian language speakers. The results presented herein, however, show that there are distinct differences in the pottery technologies of the two regions that would not be expected if the sites are directly related. Consequently, there is no clear evidence that the pottery assemblages of the northern Philippines are ancestral to those of the Marianas. While both the early Marianas Red pottery and the northern Philippines pottery assemblages originate in a red-type pottery horizon that exists in both ISEA and the Marianas, the data to date suggests only a loose affinity between the assemblages, there being a high degree of variation in the constituent pottery characteristics between regions.

Contemporary evolution has the potential to significantly alter biotic responses to global change, including range expansion dynamics and biological invasions. However, predictive models often make highly simplifying assumptions about the genetic architecture underlying relevant traits. This can be problematic since genetic architecture defines evolvability, that is, evolutionary rates, and higher order evolutionary processes, which determine whether evolution will be able to keep up with environmental change or not. Therefore, we here study the impact of the genetic architecture of dispersal and local adaptation, two central traits of high relevance for range expansion dynamics, on the speed and variability of range expansions into an environmental gradient, such as temperature. In our theoretical model we assume that dispersal and local adaptation traits result from the products of two non-interacting gene-regulatory networks (GRNs). We compare our model to simpler quantitative genetics models and show that in the GRN model, range expansions are accelerated, faster and more variable. Increased variability implies that these evolutionary changes reduce predictability. We further find that acceleration in the GRN model is primarily driven by an increase in the rate of local adaptation to novel habitats which results from greater sensitivity to mutation (decreased robustness) and increased gene expression. Our results highlight how processes at microscopic scales, here, within genomes, can impact the predictions of large scale, macroscopic phenomena, such as range expansions, by modulating the rate of evolution.

Dytiscid beetles live in spatially discrete habitat patches of varying temporal duration and ecological stability. Many species are exemplary active dispersers, moving between suitable localities, sometimes on multiple occasions within an individual’s lifetime. Despite this there is apparently much variation in the ability of individual species to disperse by flight, this having far-reaching consequences for their evolution and persistence. This chapter examines the mechanisms, causes, and consequences of dispersal in predaceous diving beetles, reviewing work on flight and flightlessness, ultimate and proximate triggers of dispersal, and the biogeographical/macroecological consequences of movement, as well as suggesting areas where further research is required. Most predaceous diving beetle species fly, but some do so far more readily and over longer temporal windows than others. The degree to which individual species disperse may be shaped largely by habitat stability and persistence something which has significant consequences for the composition of regional faunas.

MDFRC item.Freshwater rivers have been substantially altered by development and flow regulation. Altered hydrological regimes have affected a range of biota, but impacts are often most obvious on freshwater fish. Flow largely influences the range of physical habitat available to fish at various life history stages. Biological rhythms are therefore often linked to flow and optimized so that opportunities for spawning, growth and dispersal are synchronized. Assuming that flow therefore becomes the main factor which structures freshwater fish communities, the use of species specific biological information should be able to inform adaptive flow delivery strategies from the river reach to catchment scale. A test of this assertion was performed as a case study of native fish within the Edward-Wakool River system (New South Wales, Australia). Fish within the system were assigned to one of four groups based on biological similarity. Aspects of reproductive and movement ecology were then reviewed to generate optimal flow release strategies for each group. Life expectancy and hydrological constraints were then investigated and used to develop a possible 10-year flow delivery program that could generate ecological outcomes within a strategic adaptive management framework that considered potential impacts on third parties. The approach could be used to develop flow characteristics to benefit biota in any watercourse provided enough data are available to link potential outcomes with flow delivery.

Understanding the relationship between incursions of insect pests and established populations is critical to implementing effective control. Studies of genetic variation can provide powerful tools to examine potential invasion pathways and longevity of individual pest outbreaks. The major fruit fly pest in eastern Australia, Queensland fruit fly Bactrocera tryoni (Froggatt), has been subject to significant long‐term quarantine and population reduction control measures in the major horticulture production areas of southeastern Australia, at the species southern range limit. Previous studies have employed microsatellite markers to estimate gene flow between populations across this region. In this study, we used an independent genetic marker, mitochondrial DNA (mtDNA) sequences, to screen genetic variation in established and adjacent outbreak populations in southeastern Australia. During the study period, favorable environmental conditions resulted in multiple outbreaks, which appeared genetically distinctive and relatively geographically localized, implying minimal dispersal between simultaneous outbreaks. Populations in established regions were found to occur over much larger areas. Screening mtDNA (female) lineages proved to be an effective alternative genetic tool to assist in understanding fruit fly population dynamics and provide another possible molecular method that could now be employed for better understanding of the ecology and evolution of this and other pest species.

In this chapter, we consider impacts of the landscape on resistance management through its effects on abiotic and biotic conditions, behavior of pests, and selection for resistance. For efficient development of IRM, the environment needs to be characterized with respect to the spatial and temporal distribution of the pest, the crop or toxin, refuge habitats, and variation within these elements in space and time. Without an understanding of temporal and spatial variability in natural and human-designed landscapes, resistance management plans will be difficult to implement successfully. First, we highlight how heterogeneity over space influences resistance management; then we emphasize how variability over time affects IRM.

The concepts of population genetics and evolution seem simple from an abstract, academic perspective, but in reality, nature is too heterogeneous and dynamic to allow science to be so easy. To provide a reference scenario, we describe evolution by natural selection in patchy landscapes without consideration of pest density. Complications involving a variety of ecological processes are discussed. We describe random genetic drift and demographic Allee effects on evolution. We explore the complexities of genetic architecture for arthropods that evolve resistance. The roles of selection intensity, gene interaction, fitness costs, and dominance (expression of resistance) are presented. Even though most research has been on diploid arthropods, many species can be haplo-diploid (males are haploid, females are diploid). The relationship between generation time and resistance evolution is evaluated. We emphasize the importance of temporal and spatial scales for hypotheses and recommendations regarding evolution of resistance.

The high-elevation Tibetan Plateau (western China) is inhabited by a unique though not particularly species-rich community of organisms. We explored the species content and evolutionary history of the Tibetan Plateau endemic freshwater snail genus Tibetoradix. Phylogenetic relationships within the genus were reconstructed based on available sequence data. We used a single-rate Poisson Tree Processes approach for species delimitation and compared putative species-level clades with already described taxa. We found that the genus consists of at least six species, of which we described four as new to science. Shell and soft body morphology was examined and the radula in Tibetoradix was described for the first time. Based on our findings, the diversification of the genus did not result in a prominent morphological differentiation and a number of species can be regarded as morphologically cryptic. Single species found in different drainage areas indicate relatively good passive dispersal abilities of the snails. The allopatric distribution of the species could result from competitive exclusion between them. The absence of Tibetoradix spp. outside the Tibetan Plateau could be explained by a scenario of an "evolutionary trap", where adaptations to high elevation conditions prevented the taxa from a successful colonization of lower elevations. This article is protected by copyright. All rights reserved.

Two new brachypterous species of the genus Scotussa, with restricted distributions, are described for one of the most important and greatly threatened biodiversity hotspots, the Atlantic Forest. These species belong to the genus group Scotussae, a diverse group regarding mobility and oviposition habits. It has been mentioned that these characteristics could lead to restrictions in the species distribution. Based on these antecedents and considering the importance of biodiversity conservation within the Atlantic Forest, we performed novel conservation indices for this group. The rapid assessment indices calculated herein are based upon Red List status, endemism, dispersal capacity, and life-history traits that allowed us to identify areas for conservation for this group of grasshoppers. For a better understanding of the conservation status of the group, the results of the indices were compared with protected areas and Key Biodiversity Areas. Moreover, historical biome stability was also considered since it has been associated with different distributional and diversification patterns within the genus group Scotussae. The approach applied indicates that the indices recovered different but complementary information. The Grasshopper Biotic Index (GBI) determined important regions for conservation within the richest region of the group while the GBI/SiteScore located regions with lower diversity values for the group but with high importance regarding endemisms.

Breeding dispersal can influence fitness as well as the dynamics and genetic architecture of populations, but the patterns and causes of dispersal in most species are still poorly understood. Here, we used 55 years of re-sighting and breeding data from 530 individually marked adult Canada jays at the southern edge of their range in Algonquin Provincial Park, Ontario, Canada to evaluate factors that influence the probability of breeding dispersal occurrences and distances. Breeding dispersal within the study area was rare, occurring in 3% (N = 81) of the 2477 cases in which individuals were observed defending a territory in consecutive years, and only 13% (N = 68) of individuals dispersed at least once in their lifetime (mean age of dispersers = 4.75 ± 2.8). Of the 81 breeding dispersal cases, 68% (N = 55) involved a single bird, while the remaining 32% (N = 26) involved 13 cases of a mated pair dispersing together. The probability of breeding dispersal was similar between sexes, but females tended to disperse farther. Surprisingly, almost half of breeding dispersal events occurred during the autumn and winter when all or most food had already been cached. However, 70% (N = 57) of breeding dispersal events involved settlement on a neighbouring territory, which may have allowed adults to retrieve previously cached food on their original territory. Overall, adults were most likely to disperse locally when they lost a mate, had originally occupied a lower-quality territory, and a vacant position was available nearby. While the distance and rates of breeding dispersal did not change over time (N = 55), breeding dispersal events caused by mate loss, were highest in years with the steepest population decline, suggesting that a diminishing pool of mate replacements influenced breeding dispersal decisions.

Dickinsonia is an iconic fossil of the Ediacara biota (~575–539 Ma). It was previously known from siliciclastic successions of the White Sea assemblage in Australia, Baltica, and possibly India. Here we describe Dickinsonia sp. from the terminal Ediacaran Shibantan Member limestone (ca. 551–543 Ma) of the Dengying Formation in the Yangtze Gorges area of South China. The stratigraphic distribution of Ediacara-type fossils in the Shibantan Member indicates that this biota uniquely preserves both the White Sea and Nama assemblages in stratigraphic succession. The new data presented here suggests that Dickinsonia had wider paleogeographic and paleoenvironmental distributions, implying its strong dispersal capability and environmental tolerance.

PREMISE The distribution of genetic diversity on the landscape has critical ecological and evolutionary implications. This may be especially the case on a local scale for foundation plant species since they create and define ecological communities, contributing disproportionately to ecosystem function. METHODS We examined the distribution of genetic diversity and clones, which we defined first as unique multilocus genotypes (MLG), and then by grouping similar MLGs into multilocus lineages (MLL). We used 186 markers from inter-simple sequence repeats (ISSR) across 358 ramets from 13 patches of the foundation grass Leymus chinensis. We examined the relationship between genetic and clonal diversities, their variation with patch-size, and the effect of the number of markers used to evaluate genetic diversity and structure in this species. RESULTS Every ramet had a unique MLG. Almost all patches consisted of individuals belonging to a single MLL. We confirmed this with a clustering algorithm to group related genotypes. The predominance of a single lineage within each patch could be the result of the accumulation of somatic mutations, limited dispersal, some sexual reproduction with partners mainly restricted to the same patch, or a combination of all three. CONCLUSIONS We found strong genetic structure among patches of L. chinensis. Consistent with previous work on the species, the clustering of similar genotypes within patches suggests that clonal reproduction combined with somatic mutation, limited dispersal, and some degree of sexual reproduction among neighbors causes individuals within a patch to be more closely related than among patches. This article is protected by copyright. All rights reserved.

Nitrogen (N) deep placement has been found to reduce N leaching and increase N use efficiency in paddy fields. However, relatively little is known how bacterial consortia, especially abundant and rare taxa, respond to N deep placement, which is critical for understanding the biodiversity and function of agricultural ecosystem. In this study, Illumina sequencing and ecological models were conducted to examine the diversity patterns and underlying assembly mechanisms of abundant and rare taxa in rice rhizosphere soil under different N fertilization regimes at four rice growth stages in paddy fields. The results showed that abundant and rare bacteria had distinct distribution patterns in rhizosphere samples. Abundant bacteria showed ubiquitous distribution; while rare taxa exhibited uneven distribution across all samples. Stochastic processes dominated community assembly of both abundant and rare bacteria, with dispersal limitation playing a more vital role in abundant bacteria, and undominated processes playing a more important role in rare bacteria. The N deep placement was associated with a greater influence of dispersal limitation than the broadcast N fertilizer (BN) and no N fertilizer (NN) treatments in abundant and rare taxa of rhizosphere soil; while greater contributions from homogenizing dispersal were observed for BN and NN in rare taxa. Network analysis indicated that abundant taxa with closer relationships were usually more likely to occupy the central position of the network than rare taxa. Nevertheless, most of the keystone species were rare taxa and might have played essential roles in maintaining the network stability. Overall, these findings highlighted that the ecological mechanisms and co-occurrence patterns of abundant and rare bacteria in rhizosphere soil under N deep placement.

Context Plant populations in agricultural landscapes are mostly fragmented and their functional connectivity often depends on seed and pollen dispersal by animals. However, little is known about how the interactions of seed and pollen dispersers with the agricultural matrix translate into gene flow among plant populations. Objectives We aimed to identify effects of the landscape structure on the genetic diversity within, and the genetic differentiation among, spatially isolated populations of three temperate forest herbs. We asked, whether different arable crops have different effects, and whether the orientation of linear landscape elements relative to the gene dispersal direction matters. Methods We analysed the species’ population genetic structures in seven agricultural landscapes across temperate Europe using microsatellite markers. These were modelled as a function of landscape composition and configuration, which we quantified in buffer zones around, and in rectangular landscape strips between, plant populations. Results Landscape effects were diverse and often contrasting between species, reflecting their association with different pollen- or seed dispersal vectors. Differentiating crop types rather than lumping them together yielded higher proportions of explained variation. Some linear landscape elements had both a channelling and hampering effect on gene flow, depending on their orientation. Conclusions Landscape structure is a more important determinant of the species’ population genetic structure than habitat loss and fragmentation per se. Landscape planning with the aim to enhance the functional connectivity among spatially isolated plant populations should consider that even species of the same ecological guild might show distinct responses to the landscape structure.

An alfalfa grassland landscape was divided into 36 plots during 2014 season in Yuanzhou District of Guyuan city in Ningxia Hui Autonomous Region of P.R. China. In these three times repeated experiments, treatment of habitat fragmentation was divided into two grades: continuity (H = 0.0) and fragmentation (H = 1.0), and their habitat loss rate was divided into 6 grades: 90, 80, 70, 50, 20 and 0%. Considering habitat loss 0% of the plot as the reference, as a result of sweeping net and visual methods, results showed that the flight distance of the Harmonia axyridis was much higher than that of the Hippodamia variegata both in fragmentation and continuous habitats. In the alfalfa landscape, H. axyridis moved more by flying, while H. variegata moved more by crawling. There was a threshold effect that affected the movement behavior of lady beetles between 70 and 100% of the habitat loss. The population of the two species of lady beetles in the continuous habitat was higher than that in the habitat fragmentation and was more obvious in 70 and 50% plots of the habitat loss. The dispersal rate of the two species of lady beetles inside plots was higher than outside of the experimental plots, which reflected the low diffusivity of the ladybeetle. Habitat fragmentation affected the dispersal, migration and construction of two species of lady beetles on different spatial scales by disturbing the spread of natural enemies and searching for prey.

Objective To assess whether pandemic-related restrictions with video-based interviewing increased geographic clustering of urology applicants matching at a residency program near where they were raised or attended medical school. Materials and Methods We utilized publicly available data from the urology match to compare dispersal patterns between applicants matching during the COVID-19 application cycle (2021) and those matching in the 5 prior application cycles (2016-2020). Variables included home state, undergraduate institution, medical school, and residency. Latitudes and longitudes were obtained for each institution and home state. The primary endpoint was distance (miles, as the most direct path) between medical school and residency program. We also assessed dispersal patterns by American Urological Association section. Results Of the 1965 applicants matching to a urology program between 2016 and 2021, medical school was identified for 1956 (99.7%) applicants, undergraduate program for 1551 (79%) applicants, and home state for 1351 (69%) applicants. Comparing the COVID-19 application cycle to the 5 prior application cycles, there was no significant difference in the median distance between medical school and residency, undergraduate university and residency, or home state and residency. Similarly, there was no significant difference in the proportion of applicants matching at their home institution, matching from medical schools without a home urology program, matching from medical schools with a historically low volume of urology applicants ( Conclusion Virtual interviewing and the loss of in-person clinical rotations did not significantly alter dispersal patterns or hamper an applicant's ability to match at program outside their geographic region.

Given the significant impact of molecular markers on the genetic diversity assessment, understanding genetic diversity pattern across diverse marker types in a comparative manner is of great importance. In Korea, within the last 10 years population genetics studies of wild plants have drawn much attention as varying DNA markers have developed. To investigate the pattern of among-population and within-population level genetic diversity of wild plants in Korea, we reviewed the extent of population genetic parameters across four DNA markers (RAPD, AFLP, ISSR, SSR). We compiled 73 data sets from research papers published between 2010 and 2019. ISSR markers were the most frequently used in population genetics studies conducted on Korean wild plants. Overall, genetic diversity patterns greatly varied across the different marker types. On average, endangered species exhibited low within-population genetic variation and high among-population genetic diversity. Species with wide geographic distribution showed greater within-population diversity values than the ones residing in a restricted area except for AFLP data. Populations were genetically less differentiated in long distance dispersal species with wide geographic ranges. Our review indicates that the studies on the genetic diversity of wild plants may be improved by expanding the scope and increasing the sample sizes.

Hamadryas baboons, Papio hamadryas, differ from almost all other primate species in that males separate female kin by aggressively coercing females into joining their one-male units. Male behaviour thus appears to be the sole determinant of social structure, shaping patterns of relatedness. However, recent genetic studies have found that female relatedness within one-male units (OMUs) is higher than across OMUs, contrary to expected results of male behaviour. This has caused some researchers to speculate that female hamadryas baboons have some influence over dispersal. In this study, we used an agent-based model to parse how the hamadryas social system influences OMU female relatedness. We hypothesized that (1) the multilevel social structure in hamadryas baboons leads to greater-than-random relatedness in OMUs and that (2) subtle female preference leads to even higher relatedness, similar to the pattern observed in genetic data. Our agent-based model of hamadryas baboon society and dispersal was based on available field data and ran for 150 years in discrete 6-month intervals. To test hypothesis 2, we implemented manipulations mimicking female kin attraction, which increased females’ chances of being transferred into a unit containing closely related females. As output of every simulation, pedigree relatedness of adult female dyads within and across OMUs was calculated. We validated our model by comparing patterns of group size, population size, adult sex ratio and dispersal rates with available field data. The results of our simulations supported both hypotheses. Relatedness within OMUs was slightly higher than across OMUs when females had no influence over dispersal. When we implemented our scenarios of female influence on dispersal, the relatedness within OMUs increased even more, approaching the effect size of genetic data from the field. We conclude that, despite conflicting interests, a combination of male and female behaviour create a complex pattern of gene flow in this unique multilevel social system.