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This study focuses on five cores in and around three of the hundreds of shallow ephemeral hypersaline lakes distributed in chains along traces of ancient drainages that dominate the southern Western Australian landscape. Cores within and on the shore of Lake Aerodrome (LA1-09, LA2-09), Prado Lake (PL1-09, PL2-09), and Gastropod Lake (GLE1-09) in the Cowan Paleodrainage were drilled as part of a multidisciplinary study to understand the evolution of the lakes. Lithological and palynomorph data provide insights into the region's the depositional history, and floristic and climate evolution of the region. The nearly 60 m deep LA2-09 core provides the most comprehensive data. The basal ∼15 m interval of this core comprises two distinct lignite units with a clay interbed that preserve a rich palynomorph assemblage of the Werillup Formation. This assemblage is characterized by the first appearance datum (FAD) and last appearance datum (LAD) of key late Eocene taxa that correlate with the Middle Nothofagidies asperus Zone, and is indicative of freshwater swamp surrounded by subtropical to temperate rainforest. Above the upper lignite (except the topmost sample), evaporitic-siliciclastic units preserve a depauperate palynomorph assemblage comprising mostly long-ranging sclerophyllic-xerophilous-halophilic taxa. The pollen Myrtaceidites lipsis constrains the age of the upper ∼23 m interval as Pliocene to Recent. This younger assemblage also preserves reworked palynomorphs from the Werillup Formation and older units, and is identified in the other four cores. The presence of the halophilic green alga Dunaliella in the younger assemblage is used as a proxy for aridity and hypersaline conditions during post-Eocene deposition in southern Western Australia. Its absence in the neutral-alkaline lake water and uppermost core samples of GLE1-09 is either due to predation by the acidophobic gastropod Coxiella residing in the lake, or the fact that the type of Dunaliella preserved in the core samples is acidophilic. [ABSTRACT FROM AUTHOR]

Metal additive manufacturing (AM) is on its way to industrialization. One of the most promising techniques within this field, electron beam melting (EBM), is nowadays used mostly for the fabrication of high‐performance Ti‐based alloy components for the aerospace and medical industry. Among the industrial applications envisioned for the future of EBM, the fabrication of high carbon steels for the tooling industry is of great interest. In this context, the process windows for dense and crack‐free specimens for a highly alloyed (Cr–Mo–V) cold‐work steel powder are presented in this article. High‐solidification rates during EBM processing lead to very fine and homogeneous microstructures. The influence of process parameters on the resulting microstructure and the chemical composition is investigated. In addition, preliminary results show very promising mechanical properties regarding the as‐built and heat‐treated microstructure of the obtained material. [ABSTRACT FROM AUTHOR]

Extreme weather events are becoming more frequent, severe, and/or widespread as a consequence of anthropogenic climate change. While the economic and ecological implications of these changes have received considerable attention, the role of evolutionary processes in determining organismal responses to these critical challenges is currently unknown. Here we develop a novel theoretical framework that explores how alternative pathways for adaptation to rare selection events can influence population‐level vulnerabilities to future changes in the frequency, scope, and intensity of environmental extremes. We begin by showing that different life histories and trait expression profiles can shift the balance between additive and multiplicative properties of fitness accumulation, favoring different evolutionary responses to identical environmental phenomena. We then demonstrate that these different adaptive outcomes lead to predictable differences in population‐level vulnerabilities to rapid increases in the frequency, intensity, or scope of extreme weather events. Specifically, we show that when the primary mode of fitness accumulation is additive, evolution favors ignoring environmental extremes and lineages become highly vulnerable to extinction if the frequency or scope of extreme weather events suddenly increases. Conversely, when fitness accumulates primarily multiplicatively, evolution favors bet‐hedging phenotypes that cope well with historical extremes and are instead vulnerable to sudden increases in extreme event intensity. Our findings address a critical gap in our understanding of the potential consequences of rare selection events and provide a relatively simple rubric for assessing the vulnerabilities of any population of interest to changes in a wide variety of extreme environmental phenomena. [ABSTRACT FROM AUTHOR]

Colombia has some mandatory regulations for all companies, regardless their business area or their economic activity respect to Occupational Safety and Health. In this project, it was reported the results of the degree of implementation of the Occupational Safety and Health Management Systems (OSHMS) with regard to the level of obligation required by law. The data was collected from Social Security Institute survey-type instrument adapted by Autonomous University of Manizales experts; and validated through pilot testing. Throughout a convenience sampling, 26 companies in the metal/ mechanical industry of the South-central region of Caldas were evaluated. Small companies showed major gaps compared to the medium and large businesses in term of the degree of implementation of the Occupational Safety and Health Management Systems (OSHMS). Features related to compliance with the requirements of appointing staff, function assigning of the Joint Committee on Occupational safety and health, well established occupational safety and health policies, well defined spaces for first aid care; and high qualified staff to design, implement and maintain the system. [ABSTRACT FROM AUTHOR]

Ecological constraints on independent breeding are recognised as major drivers of cooperative breeding across diverse lineages. How the prevalence and degree of cooperative breeding relates to ecological variation remains unresolved. Using a large data set of cooperative nesting in Polistes wasps we demonstrate that different aspects of cooperative breeding are likely to be driven by different aspects of climate. Whether or not a species forms cooperative groups is associated with greater short-term temperature fluctuations. In contrast, the number of cooperative foundresses increases in more benign environments with warmer, wetter conditions. The same data set reveals that intraspecific responses to climate variation do not mirror genus-wide trends and instead are highly heterogeneous among species. Collectively these data suggest that the ecological drivers that lead to the origin or loss of cooperation are different from those that influence the extent of its expression within populations. [ABSTRACT FROM AUTHOR]

Current climate change is leading to increasingly unpredictable environmental conditions and is imposing new challenges to wildlife. For example, ambient conditions fluctuating during critical developmental periods could potentially impair the development of cognitive systems and may therefore have a long-term influence on an individual's life. We studied the impact of temperature variability on zebra finch cognition, focusing on song learning and song quality (N = 76 males). We used a 2 × 2 factorial experiment with two temperature conditions (stable and variable). Half of the juveniles were cross-fostered at hatching to create a mismatch between pre- and posthatching conditions, the latter matching this species' critical period for song learning. We found that temperature variability did not affect repertoire size, syllable consistency, or the proportion of syllables copied from a tutor. However, birds that experienced variable temperatures in their posthatching environment were more likely to sing during recordings. In addition, birds that experienced variable prenatal conditions had higher learning accuracy than birds in stable prenatal environments. These findings are the first documented evidence that variable ambient temperatures can influence song learning in zebra finches. Moreover, they indicate that temperature variability can act as a form of environmental enrichment with net positive effects on cognition. [ABSTRACT FROM AUTHOR]

In an era of rapid climate change, there is a pressing need to understand how organisms will cope with faster and less predictable variation in environmental conditions. Here we develop a unifying model that predicts evolutionary responses to environmentally driven fluctuating selection and use this theoretical framework to explore the potential consequences of altered environmental cycles. We first show that the parameter space determined by different combinations of predictability and timescale of environmental variation is partitioned into distinct regions where a single mode of response (reversible phenotypic plasticity, irreversible phenotypic plasticity, bet-hedging, or adaptive tracking) has a clear selective advantage over all others. We then demonstrate that, although significant environmental changes within these regions can be accommodated by evolution, most changes that involve transitions between regions result in rapid population collapse and often extinction. Thus, the boundaries between response mode regions in our model correspond to evolutionary tipping points, where even minor changes in environmental parameters can have dramatic and disproportionate consequences on population viability. Finally, we discuss how different life histories and genetic architectures may influence the location of tipping points in parameter space and the likelihood of extinction during such transitions. These insights can help identify and address some of the cryptic threats to natural populations that are likely to result from any natural or human-induced change in environmental conditions. They also demonstrate the potential value of evolutionary thinking in the study of global climate change. [ABSTRACT FROM AUTHOR]

Although ecological forces are known to shape the expression of sociality across a broad range of biological taxa, their role in shaping human behavior is currently disputed. Both comparative and experimental evidence indicate that beliefs in moralizing high gods promote cooperation among humans, a behavioral attribute known to correlate with environmental harshness in nonhuman animals. Here we combine fine-grained bioclimatic data with the latest statistical tools from ecology and the social sciences to evaluate the potential effects of environmental forces, language history, and culture on the global distribution of belief in moralizing high gods (n = 583 societies). After simultaneously accounting for potential nonindependence among societies because of shared ancestry and cultural diffusion, we find that these beliefs are more prevalent among societies that inhabit poorer environments and are more prone to ecological duress. In addition, we find that these beliefs are more likely in politically complex societies that recognize rights to movable property. Overall, our multimodel inference approach predicts the global distribution of beliefs in moralizing high gods with an accuracy of 91%, and estimates the relative importance of different potential mechanisms by which this spatial pattern may have arisen. The emerging picture is neither one of pure cultural transmission nor of simple ecological determinism, but rather a complex mixture of social, cultural, and environmental influences. Our methods and findings provide a blueprint for how the increasing wealth of ecological, linguistic, and historical data can be leveraged to understand the forces that have shaped the behavior of our own species. [ABSTRACT FROM AUTHOR]

Life on Earth is conspicuously more diverse in the tropics. Although this intriguing geographical pattern has been linked to many biotic and abiotic factors, their relative importance and potential interactions are still poorly understood. The way in which latitudinal changes in ecological conditions influence evolutionary processes is particularly controversial, as there is evidence for both a positive and a negative latitudinal gradient in speciation rates. Here, we identify and address some methodological issues (how patterns are analysed and how latitude is quantified) that could lead to such conflicting results. To address these issues, we assemble a comprehensive data set of the environmental correlates of latitude (including climate, net primary productivity and habitat heterogeneity) and combine it with biological, historical and molecular data to explore global patterns in recent divergence events (subspeciation). Surprisingly, we find that the harsher conditions that typify temperate habitats (lower primary productivity, decreased rainfall and more variable and unpredictable temperatures) are positively correlated with greater subspecies richness in terrestrial mammals and birds. Thus, our findings indicate that intraspecific divergence is greater in regions with lower biodiversity, a pattern that is robust to both sampling variation and latitudinal biases in taxonomic knowledge. We discuss possible causal mechanisms for the link between environmental harshness and subspecies richness (faster rates of evolution, greater likelihood of range discontinuities and more opportunities for divergence) and conclude that this pattern supports recent indications that latitudinal gradients of diversity are maintained by simultaneously higher potentials for both speciation and extinction in temperate than tropical regions. [ABSTRACT FROM AUTHOR]

Our species displays remarkable linguistic diversity. Although the uneven distribution of this diversity demands explanation, the drivers of these patterns have not been conclusively determined. We address this issue in two steps: First, we review previous empirical studies whose authors have suggested environmental, geographical, and sociocultural drivers of linguistic diversification. However, contradictory results and methodological variation make it difficult to draw general conclusions. Second, we outline a program for future research. We suggest that future analyses should account for interactions among causal factors, the lack of spatial and phylogenetic independence of the data, and transitory patterns. Recent analytical advances in biogeography and evolutionary biology, such as simulation modeling of diversity patterns, hold promise for testing four key mechanisms of language diversification proposed here: neutral change, population movement, contact, and selection. Future modeling approaches should also evaluate how the outcomes of these processes are influenced by demography, environmental heterogeneity, and time. [ABSTRACT FROM AUTHOR]

Environmentally-induced fluctuation in the form and strength of natural selection can drive the evolution of morphology, physiology, and behavior. Here we test the idea that fluctuating climatic conditions may also influence the process of sexual selection by inducing unexpected reversals in the relative quality or sexual attractiveness of potential breeding partners. Although this phenomenon, known as 'ecological cross-over', has been documented in a variety of species, it remains unclear the extent to which it has driven the evolution of major interspecific differences in reproductive behavior. We show that after controlling for potentially influential life history and demographic variables, there are significant positive associations between the variability and predictability of annual climatic cycles and the prevalence of infidelity and divorce within populations of a taxonomically diverse array of socially monogamous birds. Our results are consistent with the hypothesis that environmental factors have shaped the evolution of reproductive flexibility and suggest that in the absence of severe time constraints, secondary mate choice behaviors can help prevent, correct, or minimize the negative consequences of ecological cross-overs. Our findings also illustrate how a basic evolutionary process like sexual selection is susceptible to the increasing variability and unpredictability of climatic conditions that is resulting from climate change. [ABSTRACT FROM AUTHOR]

Communication is a process in which senders provide information via signals and receivers respond accordingly. This process relies on two coevolving conventions: a 'sender code' that determines what kind of signal is to be sent given the sender's state; and a 'receiver code' that determines the appropriate responses to different signal types. By means of a simple but generic model, we show that polymorphic sender and receiver strategies emerge naturally during the evolution of communication, and that the number of alternative strategies observed at equilibrium depends on the potential for error in signal production. Our model suggests that alternative communication strategies will evolve whenever senders possess imperfect information about their own quality or state, signals are costly, and genetic mechanisms allow for a correlation between sender and receiver behavior. These findings provide an explanation for recent reports of individual differences in communication strategies, and suggest that the amount of individual variation that can be expected in communication systems depends on the type of information being conveyed. Our model also suggests a link between communication and the evolution of animal personalities, which is that individual differences in the production and interpretation of signals can result in consistent differences in behavior. [ABSTRACT FROM AUTHOR]

Opponent asymmetries often determine the probability of winning a fight in agonistic situations. In many animal systems, the asymmetries that drive the dynamics and outcome of male—male contests are related to resource holding potential (RHP) or territory ownership. However, recent studies have shown that this is not the case among females and suggest that resource valuation may be more important in that context. We studied contests between the female jumping spider, Phidippus clarus, and compared them with male–male contests in this same species. Our observations document several key differences between the sexes: Precontact and contact phases are longer in females, ritualized displays are rare in females but common among males, and female fights are more likely to end in injury or death. In sharp contrast with male contests, female weight and size do not correlate with signaling behavior, and the outcome of fights is predicted by differences in resource valuation rather than RHP. We interpret these differences in light of the different natural history of the sexes and discuss how the economics of fighting may lead to the evolution of ritualized displays in males and a “desperado effect” in females. [ABSTRACT FROM PUBLISHER]

Summary: Climatic variability and unpredictability affect the distribution and abundance of resources and the timing and duration of breeding opportunities. In vertebrates, climatic variability selects for enhanced cognition when organisms compensate for environmental changes through learning and innovation . This hypothesis is supported by larger brain sizes , higher foraging innovation rates , higher reproductive flexibility , and higher sociality in species living in more variable climates. Male songbirds sing to attract females and repel rivals . Given the reliance of these displays on learning and innovation, we hypothesized that they could also be affected by climatic patterns. Here we show that in the mockingbird family (Aves: Mimidae), species subject to more variable and unpredictable climates have more elaborate song displays. We discuss two potential mechanisms for this result, both of which acknowledge that the complexity of song displays is largely driven by sexual selection . First, stronger selection in more variable and unpredictable climates could lead to the elaboration of signals of quality . Alternatively, selection for enhanced learning and innovation in more variable and unpredictable climates might lead to the evolution of signals of intelligence in the context of mate attraction . [Copyright &y& Elsevier]

Many animals repeat standardized displays multiple times while attracting a mate or deterring a rival. In such contexts the ability to perform each display or signal type in a consistent fashion may be under direct selection. Studies on sexual selection on song learning in birds have focused on differences in repertoire size with less attention paid to the potential importance of being able to perform each song/syllable type with high consistency. We investigated whether syllable type consistency is related to age, social dominance and reproductive success in tropical mockingbirds, Mimus gilvus. The variation between renditions of each syllable type decreased as the birds grew older (i.e. they became more consistent). In addition, more consistent males tended to have higher dominance status and reproductive success. These findings stress the importance of consistency in the performance of sexual displays and suggest that this parameter may be very relevant even in species that are selected for high vocal diversity (i.e. large repertoires). We hypothesize that, in addition to signalling dominance status and age, syllable type consistency may also indicate the integrity of brain function in birds analogous to the tests used for neuropsychological assessment in humans. [Copyright &y& Elsevier]

Quantifying signal repertoire size is a critical first step towards understanding the evolution of signal complexity. However, counting signal types can be so complicated and time consuming when repertoire size is large, that this trait is often estimated rather than measured directly. We studied how three common methods for repertoire size quantification (i.e., simple enumeration, curve-fitting and capture-recapture analysis) are affected by sample size and presentation style using simulated repertoires of known sizes. As expected, estimation error decreased with increasing sample size and varied among presentation styles. More surprisingly, for all but one of the presentation styles studied, curve-fitting and capture–recapture analysis yielded errors of similar or greater magnitude than the errors researchers would make by simply assuming that the number of types in an incomplete sample is the true repertoire size. Our results also indicate that studies based on incomplete samples are likely to yield incorrect ranking of individuals and spurious correlations with other parameters regardless of the technique of choice. Finally, we argue that biological receivers face similar difficulties in quantifying repertoire size than human observers and we explore some of the biological implications of this hypothesis. [ABSTRACT FROM AUTHOR]

It has been suggested that individual recognition based on song may be constrained by repertoire size in songbirds with very large song repertoires. This hypothesis has been difficult to test because there are few studies on species with very large repertoires and because traditional experiments based on the dear enemy effect do not provide evidence against recognition. The tropical mockingbird, Mimus gilvus, is a cooperative breeder with very large song repertoires and stable territorial neighbourhoods. The social system of this species allowed us to test individual recognition based on song independently from the dear enemy effect by evaluating male response to playback of strangers, neighbours (from shared and unshared boundaries), co-males (i.e. other males in the same social group) and own songs. Although subjects did not show a dear enemy effect, they were less aggressive to co-males than to all other singers. Our results suggest that recognition in tropical mockingbirds (1) does not simply distinguish between familiar and unfamiliar singers, (2) requires a small sample of both songs and song types, (3) does not rely on individual-specific sequences of song types and (4) is not likely to rely on group-specific vocal signatures potentially available in cooperatively breeding groups. We conclude that this is a case of true recognition and we suggest that the lack of a dear enemy effect in this and other species with large repertoires may relate to the role of song in mate attraction and the perception of neighbours as a threat to future paternity. [Copyright &y& Elsevier]

Despite their large vocal repertoires and otherwise highly versatile singing style, male mockingbirds (Mimus spp.) sometimes sing in a highly repetitive fashion. We conducted a playback experiment to determine the possible signal value of different syllable-presentation patterns during simulated male intrusions in the Tropical Mockingbird (Mimus gilvus), testing the hypothesis that more repetitive singing represents a stronger threat and generates a stronger aggressive response. Responses were measured in terms of approach and singing behavior and were analyzed using McGregor's (1992) multivariate method. We also introduce the use of survival analysis for analyzing response variables for which subjects do not perform the behavior in question in at least one of the replicates (known as "right-censored variables" in the statistical literature). As predicted by theory, experimental subjects responded more aggressively to songs composed of a single note than to variable ones. However, versatility at the between-song level had an opposite effect: high song-switching rates generated stronger responses than low ones. Given the lack of a statistical interaction between within-song versatility and switching rate, we conclude that these two parameters may serve independent purposes and possibly transmit different information. We discuss the possibility that the signal value of variation in vocal versatility lies in the mediation of territorial conflicts, the attraction of female partners, the mediation of conflicts over access to reproductive females, or some combination of these functions. [ABSTRACT FROM AUTHOR]

In this work, a highly alloyed cold work tool steel, Uddeholm Vanadis 4 Extra, was manufactured via the electron beam melting (EBM) technique. The corresponding material microstructure and carbide precipitation behavior as well as the microstructural changes after heat treatment were characterized, and key mechanical properties were investigated. In the as-built condition, the microstructure consists of a discontinuous network of very fine primary Mo- and V-rich carbides dispersed in an auto-tempered martensite matrix together with ≈15% of retained austenite. Adjusted heat treatment procedures allowed optimizing the microstructure by the elimination of Mo-rich carbides and the precipitation of fine and different sized V-rich carbides, along with a decrease in the retained austenite content below 2%. Hardness response, compressive strength, and abrasive wear properties of the EBM-manufactured material are similar or superior to its as-HIP forged counterparts manufactured using traditional powder metallurgy route. In the material as built by EBM, an impact toughness of 16–17 J was achieved. Hot isostatic pressing (HIP) was applied in order to further increase ductility and to investigate its impact upon the microstructure and properties of the material. After HIPing with optimized protocols, the ductility increased over 20 J. [ABSTRACT FROM AUTHOR]

Anthropogenic climate change is rapidly altering local environments and threatening biodiversity throughout the world. Although many wildlife responses to this phenomenon appear largely idiosyncratic, a wealth of basic research on this topic is enabling the identification of general patterns across taxa. Here, we expand those efforts by investigating how avian responses to climate change are affected by the ability to cope with ecological variation through behavioural flexibility (as measured by relative brain size). After accounting for the effects of phylogenetic uncertainty and interspecific variation in adaptive potential, we confirm that although climate warming is generally correlated with major body size reductions in North American migrants, these responses are significantly weaker in species with larger relative brain sizes. Our findings suggest that cognition can play an important role in organismal responses to global change by actively buffering individuals from the environmental effects of warming temperatures. [ABSTRACT FROM AUTHOR]

Evolutionary compromises are thought to be common under fluctuating selection because the mutations that best enable adaptation to one environmental context can often be detrimental to others. Yet, prior experimental work has shown that generalists can sometimes perform as well as specialists in their own environments. Here we use a highly replicated evolutionary experiment (N  = 448 asexual lineages of the brewer's yeast) to show that even though fluctuation between two environmental conditions often induces evolutionary compromises (at least early on), it can also help reveal difficult to reach adaptive outcomes that ultimately improve performance in both environments. Specifically, we begin by showing that yeast adaptation to chemical stress can involve fitness trade-offs with stress-free environments and that, accordingly, lineages that are repeatedly exposed to occasional stress tend to respond by trading performance for breadth of adaptation. We then show that on rare occasions, fluctuating selection leads to the evolution of no-cost generalists that can even outcompete constant selection specialists in their own environments. We propose that the discovery of these broader and more effective adaptive outcomes under fluctuating selection could be partially facilitated by changes in the adaptive landscape that result from having to deal with fitness trade-offs across different environmental conditions. Overall, our findings indicate that reconciling the short- and long-term evolutionary consequences of fluctuating selection could significantly improve our understanding of the evolution of specialization and generalism. [ABSTRACT FROM AUTHOR]

Organizations must ensure that their work areas are integrated and the processes they carry out are aimed at organizational objectives. Historically there has been a conflict between the production and maintenance areas, since each of these areas prioritizes objectives that in most cases are not consistent with the overall objectives of the organization. In this way, it is intended to determine if there are articulation components between maintenance management and manufacturing strategies; from the analysis of primary information, collected with methodological tools designed by experts of the Universidad Autónoma de Manizales and validated by pilot test. It is confirmed how the flexibility strategies, to which organizations resort to respond to the demands and variations of the market, present a statistical association with the way maintenance management is directed, so that production changes are in accordance with the functions of maintenance. A general level, it can be seen that companies that have a maintenance management implemented take into account the characteristics of production management, as is the case of linear flow configurations that require maintenance with the minimum machine setup time. [ABSTRACT FROM AUTHOR]

Highly ordered TiO2 nanotubes were obtained by anodization on Ti6Al4V substrates manufactured by electron beam powder bed fusion (E-PBF). Effects of anodization parameters such as anodizing time, stirring, fluoride concentration, and water content were analyzed in an organic electrolyte (ethylene glycol) that contains ammonium fluoride. The ordering of the nanotubes was measured by regularity ratio calculations based on fast Fourier transform (FFT) from SEM images. It was found that for the processed specimens, the highest ordering of the TiO2 nanotubes was reached at 30 V for 5000 s with a concentration of 9 vol% H2O and 0.4 wt.% NH4F, exhibiting nanotubes free of delamination, cracks, and coral-like structures with a regularity ratio (RR) of 1.91. This work offers a simple method for creating homogeneous and organized TiO2 nanotubes on Ti6Al4V substrates manufactured by E-PBF which potentially improves its functionality in diverse industrial applications such as nanosensors, controlled-release substances, solar cells, water splitting, electrochromic devices, and Li-ion battery anodes. [ABSTRACT FROM AUTHOR]

Presents specimen-supported evidence concerning the breeding behavior of the Ecuadorian cacique, a member of the Icteridae bird family. Breeding range of the bird in Colombia; Nest characteristics and breeding behavior of the species.

Aim: Land ownership norms are well documented and play a central role in social–ecological systems. Yet only recently has the spatial and temporal distribution of land ownership been examined using biogeographical and evolutionary approaches. We incorporate biogeographical and evolutionary modelling to test associations between land ownership and environmental, subsistence and cultural contact predictors. Location: Africa. Taxon: Bantu and Bantoid ethnolinguistic groups (73 societies). Methods: Based on ethnographies for 73 societies, we coded land ownership norms as none, group, kin or individual. We paired these data with language phylogenies, and measured phylogenetic and geographical signal and modelled alternative evolutionary trajectories using maximum likelihood methods. We tested the influence of environmental, subsistence and cultural predictors on spatial variation in land ownership, using a multi‐model inference approach based on logistic regression. Results: Bantu land ownership norms likely evolved on a unilinear trajectory (i.e. societies progress or regress along a series of ownership types), but not one requiring consistent increase in exclusivity (i.e. restrictions towards ownership by smaller groups) as suggested by prior theory. Our biogeographical analyses suggest land ownership is more likely where neighbours also own land and resource productivity is predictable. Reliance on agriculture has relatively small effect sizes and low importance in the model. Main Conclusions: We find support for multiple evolutionary pathways. Lack of resolution may be due to localized horizontal transfer of norms consistent with the influence of neighbours we find from biogeographical analyses. We cannot rule out other untested mechanisms. Although long‐standing theories propose links between subsistence practices and land ownership, our results suggest subsistence plays only a modest role. Our results also support resource defensibility theory (i.e. land ownership is more likely where environmental productivity is predictable). Overall, we demonstrate the value of combining analytical approaches from evolution and biogeography to test hypotheses on the spatial and temporal variation of human cultural traits. [ABSTRACT FROM AUTHOR]

Sexual selection is proposed to be an important driver of diversification in animal systems, yet previous tests of this hypothesis have produced mixed results and the mechanisms involved remain unclear. Here, we use a novel phylogenetic approach to assess the influence of sexual selection on patterns of evolutionary change during 84 recent speciation events across 23 passerine bird families. We show that elevated levels of sexual selection are associated with more rapid phenotypic divergence between related lineages, and that this effect is restricted to male plumage traits proposed to function in mate choice and species recognition. Conversely, we found no evidence that sexual selection promoted divergence in female plumage traits, or in male traits related to foraging and locomotion. These results provide strong evidence that female choice and male-male competition are dominant mechanisms driving divergence during speciation in birds, potentially linking sexual selection to the accelerated evolution of pre-mating reproductive isolation. [ABSTRACT FROM AUTHOR]

The Uto-Aztecan language family is one of the largest language families in the Americas. However, there has been considerable debate about its origin and how it spread. Here we use Bayesian phylogenetic methods to analyze lexical data from thirty-four Uto-Aztecan varieties and two Kiowa-Tanoan languages. We infer the age of Proto-Uto-Aztecan to be around 4,100 years (3,258-5,025 years) and identify the most likely homeland to be near what is now Southern California. We reconstruct the most probable subsistence strategy in the ancestral Uto-Aztecan society and infer no casual or intensive cultivation, an absence of cereal crops, and a primary subsistence mode of gathering (rather than agriculture). Our results therefore support the timing, geography, and cultural practices of a northern origin and are inconsistent with alternative scenarios. [ABSTRACT FROM AUTHOR]

Understanding variation in abundance within species' ranges is fundamental for ecological and evolutionary theory and applied conservation science. The abundant‐center model provides a general hypothesis based on basic ecological principles and macroscale biogeographic patterns: abundance should peak near the center of a species' range, where environmental conditions are most favorable, and decline towards the periphery. Despite longstanding influence in ecological thinking, consistent support for the ubiquity of abundant‐center distributions remains elusive, and recent assessments have questioned the value of this paradigm altogether. We suggest that revisiting the simplifying assumptions that underly the model provides a productive path forward by clarifying predictions and revealing expectations for alternative distribution patterns. Towards this end, we use standardized abundance surveys of North American birds to reassess the prevalence of abundant‐center distributions in geographic and climate space, test whether deviations are associated with predictable violations of assumptions, and provide more robust expectations. After accounting for common methodological pitfalls, we find that geographic centrality is generally indicative of centrality in climate space (confirming a key model assumption) and that abundant‐center distributions occurred in 71% of passerines. To better understand exceptions, we introduce the concept of abundant‐core distributions, of which the abundant‐center is a special case. We find that 87% of species fit abundant‐core expectations, with abundances peaked and generally declining from a core region within the range. Abundance cores tended to deviate from geographic center where topographic features complicate correspondence between geography and environmental conditions (e.g. the climatically heterogenous west). Such deviations were often associated with truncated climatic availability, with core regions offset towards the continental edge or climate extremes. Overall, our analyses suggest that abundant‐center thinking provides a useful generalization for understanding spatial variation in abundance for many species. However, as with any model, its assumptions must be assessed within the context of given applications. [ABSTRACT FROM AUTHOR]

Resource managers have rarely accounted for evolutionary dynamics in the design or implementation of climate change adaptation strategies. We brought the research and management communities together to identify challenges and opportunities for applying evidence from evolutionary science to support on‐the‐ground actions intended to enhance species' evolutionary potential. We amalgamated input from natural‐resource practitioners and interdisciplinary scientists to identify information needs, current knowledge that can fill those needs, and future avenues for research. Three focal areas that can guide engagement include: (1) recognizing when to act, (2) understanding the feasibility of assessing evolutionary potential, and (3) identifying best management practices. Although researchers commonly propose using molecular methods to estimate genetic diversity and gene flow as key indicators of evolutionary potential, we offer guidance on several additional attributes (and their proxies) that may also guide decision‐making, particularly in the absence of genetic data. Finally, we outline existing decision‐making frameworks that can help managers compare alternative strategies for supporting evolutionary potential, with the goal of increasing the effective use of evolutionary information, particularly for species of conservation concern. We caution, however, that arguing over nuance can generate confusion; instead, dedicating increased focus on a decision‐relevant evidence base may better lend itself to climate adaptation actions. [ABSTRACT FROM AUTHOR]

Mechanical behavior of additively manufactured lattice materials has been mainly investigated under uniaxial compression, while their performance under uniaxial and multiaxial tension are yet to be understood. To address this gap, a generic elastoplastic homogenization scheme with continuum damage model is developed, and three different lattice materials, namely cubic, modified face-center cubic and body-center cubic, are analyzed under uniaxial, biaxial and triaxial tension. The influence of micro-architecture on the material's failure behavior as well as its macroscopic mechanical performance is thoroughly discussed. For validation, a set of uniaxial tensile experiments are conducted on functionally graded cubic lattice samples that are additively manufactured using Electron Beam Melting (EBM) process. Digital image correlation technique is employed to obtain the macroscopic stress–strain curves, and manufacturing imperfections are inspected using light omitting microscopy. It turns out that the behavior of as-built samples could substantially differ from numerical predictions. Thus, a defect-informed numerical model is employed to accommodate the effect of imperfections. The outcome is in a very good agreement with experimental data, indicating that with proper input data, the developed scheme can accurately predict the mechanical and failure behavior of a given lattice material. [ABSTRACT FROM AUTHOR]

Competitive fitness assays in liquid culture have been a mainstay for characterizing experimental evolution of microbial populations. Growth of microbial strains has also been extensively characterized by colony size and could serve as a useful alternative if translated to per generation measurements of relative fitness. To examine fitness based on colony size, we established a relationship between cell number and colony size for strains of Saccharomyces cerevisiae robotically pinned onto solid agar plates in a high-density format. This was used to measure growth rates and estimate relative fitness differences between evolved strains and their ancestors. After controlling for edge effects through both normalization and agar-trimming, we found that colony size is a sensitive measure of fitness, capable of detecting 1% differences. While fitnesses determined from liquid and solid mediums were not equivalent, our results demonstrate that colony size provides a sensitive means of measuring fitness that is particularly well suited to measurements across many environments. [ABSTRACT FROM AUTHOR]

There is an imperative for conservation practitioners to help biodiversity adapt to accelerating environmental change. Evolutionary biologists are well‐positioned to inform the development of evidence‐based management strategies that support the adaptive capacity of species and ecosystems. Conservation practitioners increasingly accept that management practices must accommodate rapid environmental change, but harbour concerns about how to apply recommended changes to their management contexts. Given the interest from both conservation practitioners and evolutionary biologists in adjusting management practices, we believe there is an opportunity to accelerate the required changes by promoting closer collaboration between these two groups. We highlight how evolutionary biologists can harness lessons from other disciplines about how to foster effective knowledge exchange to make a substantive contribution to the development of effective conservation practices. These lessons include the following: (1) recognizing why practitioners do and do not use scientific evidence; (2) building an evidence base that will influence management decisions; (3) translating theory into a format that conservation practitioners can use to inform management practices; and (4) developing strategies for effective knowledge exchange. Although efforts will be required on both sides, we believe there are rewards for both practitioners and evolutionary biologists, not least of which is fostering practices to help support the long‐term persistence of species. [ABSTRACT FROM AUTHOR]

Modern phylogenetic methods are increasingly being used to address questions about macro-level patterns in cultural evolution. These methods can illuminate the unobservable histories of cultural traits and identify the evolutionary drivers of trait change over time, but their application is not without pitfalls. Here, we outline the current scope of research in cultural tree thinking, highlighting a toolkit of best practices to navigate and avoid the pitfalls and 'abuses' associated with their application. We emphasize two principles that support the appropriate application of phylogenetic methodologies in cross-cultural research: researchers should (1) draw on multiple lines of evidence when deciding if and which types of phylogenetic methods and models are suitable for their cross-cultural data, and (2) carefully consider how different cultural traits might have different evolutionary histories across space and time. When used appropriately phylogenetic methods can provide powerful insights into the processes of evolutionary change that have shaped the broad patterns of human history. This article is part of the theme issue 'Foundations of cultural evolution'. [ABSTRACT FROM AUTHOR]

Land ownership shapes natural resource management and social–ecological resilience, but the factors determining ownership norms in human societies remain unclear. Here we conduct a global empirical test of long‐standing theories from ecology, economics and anthropology regarding potential drivers of land ownership and territoriality. Prior theory suggests that resource defensibility, subsistence strategies, population pressure, political complexity and cultural transmission mechanisms may all influence land ownership. We applied multi‐model inference procedures based on logistic regression to cultural and environmental data from 102 societies, 71 with some form of land ownership and 31 with no land ownership. We found an increased probability of land ownership in mountainous environments, where patchy resources may be more cost effective to defend via ownership. We also uncovered support for the role of population pressure, with a greater probability of land ownership in societies living at higher population densities. Our results also show more land ownership when neighboring societies also practiced ownership. We found less support for variables associated with subsistence strategies and political complexity. [ABSTRACT FROM AUTHOR]

The role of sexual selection as a driver of speciation remains unresolved, not least because we lack a clear empirical understanding of its influence on different phases of the speciation process. Here, using data from 1306 recent avian speciation events, we show that plumage dichromatism (a proxy for sexual selection) does not predict diversification rates, but instead explains the rate at which young lineages achieve geographical range overlap. Importantly, this effect is only significant when range overlap is narrow (< 20%). These findings are consistent with a 'differential fusion' model wherein sexual selection reduces rates of fusion among lineages undergoing secondary contact, facilitating parapatry or limited co-existence, whereas more extensive sympatry is contingent on additional factors such as ecological differentiation. Our results provide a more mechanistic explanation for why sexual selection appears to drive early stages of speciation while playing a seemingly limited role in determining broad-scale patterns of diversification. [ABSTRACT FROM AUTHOR]

Cooperative breeding is an extreme form of cooperation that evolved in a range of lineages, including arthropods, fish, birds, and mammals. Although cooperative breeding in birds is widespread and well-studied, the conditions that favored its evolution are still unclear. Based on phylogenetic comparative analyses on 3,005 bird species, we demonstrate here that family living acted as an essential stepping stone in the evolution of cooperative breeding in the vast majority of species. First, families formed by prolonging parent–offspring associations beyond nutritional independency, and second, retained offspring began helping at the nest. These findings suggest that assessment of the conditions that favor the evolution of cooperative breeding can be confounded if this process is not considered to include 2 steps. Specifically, phylogenetic linear mixed models show that the formation of families was associated with more productive and seasonal environments, where prolonged parent–offspring associations are likely to be less costly. However, our data show that the subsequent evolution of cooperative breeding was instead linked to environments with variable productivity, where helpers at the nest can buffer reproductive failure in harsh years. The proposed 2-step framework helps resolve current disagreements about the role of environmental forces in the evolution of cooperative breeding and better explains the geographic distribution of this trait. Many geographic hotspots of cooperative breeding have experienced a historical decline in productivity, suggesting that a higher proportion of family-living species could have been able to avoid extinction under harshening conditions through the evolution of cooperative breeding. These findings underscore the importance of considering the potentially different factors that drive different steps in the evolution of complex adaptations. [ABSTRACT FROM AUTHOR]

Aim Two fundamental questions about human language demand answers: why are so many languages spoken today and why is their geographical distribution so uneven? Although hypotheses have been proposed for centuries, the processes that determine patterns of linguistic and cultural diversity remain poorly understood. Previous studies, which relied on correlative, curve-fitting approaches, have produced contradictory results. Here we present the first application of process-based simulation modelling, derived from macroecology, to examine the distribution of human groups and their languages. Location The Australian continent is used as a case study to demonstrate the power of simulation modelling for identifying processes shaping the diversity and distribution of human languages. Methods Process-based simulation models allow investigators to hold certain factors constant in order to isolate and assess the impact of modelled processes. We tested the extent to which a minimal set of processes determines the number and spatial distribution of languages on the Australian continent. Our model made three basic assumptions based on previously proposed, but untested, hypotheses: groups fill unoccupied spaces, rainfall limits population density and groups divide after reaching a maximum population. Results Remarkably, this simple model accurately predicted the total number of languages (average estimate 406, observed 407), and explained 56% of spatial variation in language richness on the Australian continent. Main conclusions Our results present strong evidence that current climatic conditions and limits to group size are important processes shaping language diversity patterns in Australia. Our study also demonstrates how simulation models from macroecology can be used to understand the processes that have shaped human cultural diversity across the globe. [ABSTRACT FROM AUTHOR]

From the foods we eat and the houses we construct, to our religious practices and political organization, to who we can marry and the types of games we teach our children, the diversity of cultural practices in the world is astounding. Yet, our ability to visualize and understand this diversity is limited by the ways it has been documented and shared: on a culture-by-culture basis, in locally-told stories or difficult-to-access repositories. In this paper we introduce D-PLACE, the Database of Places, Language, Culture, and Environment. This expandable and open-access database (accessible at ) brings together a dispersed corpus of information on the geography, language, culture, and environment of over 1400 human societies. We aim to enable researchers to investigate the extent to which patterns in cultural diversity are shaped by different forces, including shared history, demographics, migration/diffusion, cultural innovations, and environmental and ecological conditions. We detail how D-PLACE helps to overcome four common barriers to understanding these forces: i) location of relevant cultural data, (ii) linking data from distinct sources using diverse ethnonyms, (iii) variable time and place foci for data, and (iv) spatial and historical dependencies among cultural groups that present challenges for analysis. D-PLACE facilitates the visualisation of relationships among cultural groups and between people and their environments, with results downloadable as tables, on a map, or on a linguistic tree. We also describe how D-PLACE can be used for exploratory, predictive, and evolutionary analyses of cultural diversity by a range of users, from members of the worldwide public interested in contrasting their own cultural practices with those of other societies, to researchers using large-scale computational phylogenetic analyses to study cultural evolution. In summary, we hope that D-PLACE will enable new lines of investigation into the major drivers of cultural change and global patterns of cultural diversity. [ABSTRACT FROM AUTHOR]

Abstract: The mockingbirds, thrashers and allied birds in the family Mimidae are broadly distributed across the Americas. Many aspects of their phylogenetic history are well established, but there has been no previous phylogenetic study that included all species in this radiation. Our reconstructions based on mitochondrial and nuclear DNA sequence markers show that an early bifurcation separated the Mimidae into two clades, the first of which includes North and Middle American taxa (Melanotis, Melanoptila, Dumetella) plus a small radiation that likely occurred largely within the West Indies (Ramphocinclus, Allenia, Margarops, Cinclocerthia). The second and larger radiation includes the Toxostoma thrasher clade, along with the monotypic Sage Thrasher (Oreoscoptes) and the phenotypically diverse and broadly distributed Mimus mockingbirds. This mockingbird group is biogeographically notable for including several lineages that colonized and diverged on isolated islands, including the Socorro Mockingbird (Mimus graysoni, formerly Mimodes) and the diverse and historically important Galapagos mockingbirds (formerly Nesomimus). Our reconstructions support a sister relationship between the Galapagos mockingbird lineage and the Bahama Mockingbird (M. gundlachi) of the West Indies, rather than the Long-tailed Mockingbird (M. longicaudatus) or other species presently found on the South American mainland. Relationships within the genus Toxostoma conflict with traditional arrangements but support a tree based on a preivous mtDNA study. For instance, the southern Mexican endemic Ocellated Thrasher (T. ocellatum) is not an isolated sister species of the Curve-billed thrasher (T. curvirostre). [Copyright &y& Elsevier]