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Active learning increases student learning, engagement, and interest in STEM and subsequently, the number and diversity of graduates. Yet, its adoption has been slow, partially due to instructors’ ... more...

Considerable progress has been achieved in resolving higher-level relationships of Arthropoda in the past two decades, largely precipitated by advances in sequencing technology. Yet, dark branches persist in the arthropod tree of life, principally among groups that are difficult to collect, occur in cryptic habitats, or are characterized by minute body size. Among chelicerates, the mesodiverse order Solifugae (commonly called camel spiders or sun spiders) is one of the last orders of Arachnida that lacks a higher-level phylogeny altogether and has long been characterized as one of the “neglected cousins”, a lineage of arachnid orders that are comparatively poorly studied with respect to evolutionary relationships. Though renowned for their aggression, remarkable running speed, and adaptation to arid habitats, inferring solifuge relationships has been hindered by inaccessibility of diagnostic characters in most ontogenetic stages for morphological datasets, whereas molecular investigations to date have been limited to one of the 12 recognized families. In this study we generated a phylogenomic dataset via capture of ultraconserved elements (UCEs) and sampled all extant families. We recovered a well-resolved phylogeny of solifuge families, with two distinct groups of New World taxa nested within a broader Paleotropical radiation. To provide a temporal context to solifuge diversification, we estimated molecular divergence times using fossil calibrations within a least-squares framework. Solifugae were inferred to have radiated by the Permian, with divergences of most families dating to the post Paleogene-Cretaceous extinction. These results accord with a diversification history largely driven by vicariance as a result of continental breakup. more...

The Southern Appalachians and adjacent provinces of the southeastern USA are geologically and biologically diverse, with high levels of endemism. Phylogeographic analyses indicate that animals with small distributions in these regions often contain cryptic diversity and that Pleistocene climate fluctuations had significant impacts on their distributions. We studied the phylogeography of Vaejovis carolinianus (Beauvois), a common forest scorpion from the region, to determine if a more widely distributed animal exhibits similar patterns. Mitochondrial and nuclear DNA, as well as species distribution models, were used to test biogeographic hypotheses. Results indicate that the species is composed of at least nine geographically structured mitochondrial clades. Seven clades are represented by only a few sampling locations, whereas two clades are much larger and appear to be the result of postglacial range expansion in the plateaus and coastal plains adjacent to the Southern Appalachians. A highly disjunct population from Tunica Hills of Louisiana appears to have been isolated since the Pliocene, rejecting a hypothesis of late glacial migration along the Blufflands escarpment. Nuclear DNA is much less structured, perhaps due to differences in habitat and dispersal capabilities between sexes. Although mitochondrial lineages are quite old, mito-nuclear discordance suggests that lineages have not sorted and that V. carolinianus should be treated as a single genetically diverse species. more...

Debates over curricula can be understood as struggles over the power to define symbolic representations of the world. Although this tension is particularly visible in discourse around textbook adop... more...

Adopting evidence-based teaching practices, such as active learning, has proven to increase student learning, engagement, and interest in STEM and subsequently, the number and diversity of STEM gra... more...

Scorpions represent an ancient lineage of arachnids that have radiated across the globe and are incredibly resilient—since some thrive in harsh environments and can exist on minimal and intermittent feedings. Given the emerging importance of microbiomes to an organism’s health, it is intriguing to suggest that the long-term success of the scorpion bauplan may be linked to the microbiome. Little is known about scorpion microbiomes, and what is known, concentrates on the gut. The microbiome is not limited to the gut, rather it can be found within tissues, fluids and on external surfaces. We tested whether the scorpion telson, the venom-producing organ, of two species, Smeringurus mesaensis and Hadrurus arizonensis, contain bacteria. We isolated telson DNA from each species, amplified bacterial 16S rRNA genes, and identified the collection of bacteria present within each scorpion species. Our results show for the first time that telsons of non-buthid scorpion species do indeed contain bacteria. Interestingly, each scorpion species has a phylogenetically unique telson microbiome including Mollicutes symbionts. This study may change how we view scorpion biology and their venoms. more...

Venom from Amazonian scorpions of the genus Tityus contains components capable of eliciting a distinct clinical, mostly neurological, syndrome. This contrasts with the mainly autonomic manifestations produced after envenomation by congeneric southern and northern South American species. Herein, we summarize Pan-Amazonian scorpionism by synthesizing available toxinological, clinical, and molecular data gathered from all affected areas in Amazonia, including Brazil, Ecuador, Colombia, Peru, Venezuela, and French Guiana. We searched multiple databases, as well as our own records, for reports of scorpion envenomations in Amazonia by confirmed Tityus spp., and compared the clinical manifestations. To help uncover clinical and venom relationships among problematic species, we explored phylogenetic relationships with a rate-calibrated analysis of mitochondrial COI data from available species. The possible existence of diversity gradients for venom toxic and immunogenic components despite the predicted strong phylogenetic association among species is underscored by discussed clinical and toxinological findings. A multicentric effort, involving all nations affected by this neglected disease, is urgently needed to offer alternatives for treating and understanding this pathology, including the preparation of neutralizing antibodies with a broad range of efficacy. more...

AIM: To review the histories of the Colorado River and North American monsoon system to ascertain their effects on the genetic divergence of desert‐adapted animals. LOCATION: Lower Colorado River region, including Mojave and Sonoran deserts, United States. METHODS: We synthesized recent geological literature to summarize initiation phases of lower Colorado River evolution, their discrepancies, and potential for post‐vicariance dispersal of animals across the river. We simulated data under geological models and performed a meta‐analysis of published and unpublished genetic data including population diversity metrics, relatedness and historical migration rates to assess alternative divergence hypotheses. RESULTS: The two models for arrival of the Colorado River into the Gulf of California impose east‐west divergence ages of 5.3 and 4.8 Ma, respectively. We found quantifiable river‐associated differentiation in the lower Colorado River region in reptiles, arachnids and mammals relative to flying insects. However, topological statistics, historical migration rates and cross‐river extralimital populations suggest that the river should be considered a leaky barrier that filters, rather than prevents, gene flow. Most markers violated neutrality tests. Differential adaptation to monsoon‐based precipitation differences may contribute to divergence between Mojave and Sonoran populations and should be tested. MAIN CONCLUSIONS: Rivers are dynamic features that can both limit and facilitate gene flow through time, the impacts of which are mitigated by species‐specific life history and dispersal traits. The Southwest is a geo‐climatically complex region with the potential to produce pseudocongruent patterns of genetic divergence, offering a good setting to evaluate intermediate levels of geological‐biological (geobiological) complexity. more...

Due to the COVID-19 pandemic, many key neglected tropical disease (NTD) activities have been postponed. This hindrance comes at a time when the NTDs are progressing towards their ambitious goals for 2030. Mathematical modelling on several NTDs, namely gambiense sleeping sickness, lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiases (STH), trachoma, and visceral leishmaniasis, shows that the impact of this disruption will vary across the diseases. Programs face a risk of resurgence, which will be fastest in high-transmission areas. Furthermore, of the mass drug administration diseases, schistosomiasis, STH, and trachoma are likely to encounter faster resurgence. The case-finding diseases (gambiense sleeping sickness and visceral leishmaniasis) are likely to have fewer cases being detected but may face an increasing underlying rate of new infections. However, once programs are able to resume, there are ways to mitigate the impact and accelerate progress towards the 2030 goals., The COVID-19 pandemic has disrupted neglected tropical disease programs. Modelling shows the impact of this will vary across diseases. Once interventions are reintroduced, there are opportunities for mitigating the delay and accelerating progress towards the 2030 goals. more...

Phylogenetic relationships and evolutionary patterns within the arachnid order Solifugae are poorly understood and largely unresolved due to conserved morphology and scarce genomic resources. In this study, we evaluated the role of restriction endonuclease (RE) selection in double-digest restriction-site-associated DNA sequencing (ddRADseq) as a methodology for exploring the evolutionary history of solifuges and their responses to changing desert landscapes and climate. We optimized this method by using computer simulations to explore the effect of different enzyme combinations on the process in silico. Genome data are not yet available for Solifugae, so we performed the simulations using available spider, scorpion, tick, mite and xiphosuran genomes. Guided by the simulations, we then pioneered ddRADseq in Solifugae by generating data for four samples representing two families and three genera. Our results highlight the utility of simulated data and give us confidence that ddRADseq will be ideal for studying the evolution of solifuges. more...

Multi-modal approaches have increasingly shown promise in exploring the human side of engineering via the assessment of authentic responses to learning or working environments. This study explores the utility of non-invasive physiological wrist sensors in measuring the reactive and regulatory responses of a group of 161 engineering students taking an authentic engineering practice exam. The practice exam was categorized into Conceptual problems (e.g., rote memorization) and Analytical problems (e.g., requiring application of learned concepts through equations and free-body diagrams). Responses were measured through electrodermal activity and indicators of performance. Findings identified that the type of practice exam problem, even if designed to be within the moderate range of difficulty, influenced how students reacted to and regulated their performance to the problem (as seen by stronger positive correlations in the Analytical problems) and that these may occur via multi-componential processes. more...

Considerable evidence indicates that students’ academic motivation and engagement generally decline as they move through middle school and on to high school. This study applied social cognitive theory to explore how self-efficacy and perceived control—two main factors of personal agency—may play a role in mitigating this decline in engagement and further contribute to academic performance. We used dual change score modeling to examine the dynamic structure of personal agency and disengagement during grades 8–10 for a large sample of students from the Pacific Northwest in the U.S. In that model, we analyzed how those variables predicted grade point average and attendance for students at the end of 10th grade. Students did not necessarily become more disengaged as a result of lower perceptions of control, rather they became more disengaged without the resilience factor of self-efficacy. The actual influence of disengagement on attendance and academic performance appears to be far weaker than the role of personal agency factors. Our results indicate that when student’s self-efficacy drops, disengagement in school increases during the years transitioning to high school. Increased disengagement weakens perceived control and change in both the control and self-efficacy dimensions of personal agency drive academic performance. Schools should prioritize the development of personal agency in each student during the middle school to high school transition years. more...

In this article, we map conditions and enactments for a new plane of inquiry, what Mazzei named a minor inquiry. Informed by our collective thinking with Deleuze and Guattari’s discussion of a minor literature and its attendant characteristics, deterritorialization, political immediacy, and collective assemblage of enunciation, we present the conditions for inquiry on this new plane, provide enactments from our individual projects, and conclude with incitements for escaping the dogma of prescribed method. more...

Scorpion envenoming by species in the genus Tityus is hereby reported from rural locations in the Amazonian province of Morona Santiago, southeastern Ecuador. Twenty envenoming cases (18 patients under 15 years of age) including one death (a 4-year-old male) were recorded at the Macas General Hospital, Morona Santiago, between January 2015 and December 2016 from the counties of Taisha (n=17), Huamboyo (n=1), Palora (n=1), and Logroño (n=1). An additional fatality from 2014 (a 3-year-old female from Nayantza, Taisha county) is also reported. Leukocytosis and low serum potassium levels were detected in most patients. We observed a significant negative correlation between leukocytosis and hypokalemia. Scorpions involved in three accidents from Macuma, Taisha County, were identified as genetically related to Tityus obscurus from the Brazilian Amazonian region based on comparison of mitochondrial DNA sequences encoding cytochrome oxidase subunit I. These cases, along with previously reported envenoming from northern Manabí, reinforce the notion that scorpionism is a health hazard for children in Ecuador and emphasizes the need to supply effective antivenoms against local species, which are not currently available. The genetic affinity of the Ecuadorian specimens with T. obscurus may underlay toxinological, clinical, and venom antigenic relationships among Amazonian scorpions that deserves further exploration for designing therapeutic strategies to treat scorpionism in the region. more...

Montane species endemic to the "sky islands" of the North American southwest were significantly impacted by changing climates during the Pleistocene. We combined mitochondrial and genomic data with species distribution modelling to determine whether Aphonopelma marxi, a large tarantula from the nearby Colorado Plateau, was similarly impacted by glacial climates. Genetic analyses revealed that the species comprises three main clades that diverged in the Pleistocene. A clade distributed along the Mogollon Rim appears to have persisted in place during glacial conditions, whereas the other two clades probably colonized central and northeastern portions of the species' range from refugia in canyons. Climate models support this hypothesis for the Mogollon Rim, but late glacial climate data appear too coarse to detect suitable areas in canyons. Locations of canyon refugia could not be inferred from genomic analyses due to missing data, encouraging us to explore the effect of missing loci in phylogeographical inferences using RADseq. Results from analyses with varying amounts of missing data suggest that samples with large amounts of missing data can still improve inferences, and the specific loci that are missing matters more than the number of missing loci. This study highlights the profound impact of Pleistocene climates on tarantulas endemic to the Colorado Plateau, as well as the mixed nature of the region's fauna. Some animals recently colonized from nearby deserts as glacial climates receded, whereas others, like tarantulas, appear to have persisted on the Mogollon Rim and in refugia associated with the region's famous river-cut canyons. more...

Envenoming by scorpions in genus Tityus is a public health problem in Tropical America. One of the most medically significant species is Tityus trivittatus, which is known to occur from southwest Brazil to central-northern and eastern Argentina. In this work, we studied the lethality, composition, antigenicity, and enzymatic activity of venom from a T. trivittatus population found further north in urban areas of eastern Paraguay, where it has caused serious envenomation of children. Our results indicate that the population is of medical importance as it produces a potently toxic venom with an LD50 around 1.19 mg/kg. Venom neutralization in preliminary mouse bioassays was complete when using Brazilian anti-T. serrulatus antivenom but only partial when using Argentinean anti-T. trivittatus antivenom. Venom competitive solid-phase enzyme immunoassays and immunoblotting from Argentinean and Paraguayan T. trivittatus populations indicated that antigenic differences exist across the species range. SDS-PAGE showed variations in type and relative amounts of venom proteins between T. trivitattus samples from Argentina and Paraguay. MALDI-TOF mass spectrometry indicated that while some sodium channel toxins are shared, including β-toxin Tt1g, others are population-specific. Proteolytic activity by zymography and peptide identification through nESI-MS/MS also point out that population-specific proteases may exist in T. trivitattus, which are postulated to be involved in the envenoming process. A time-calibrated molecular phylogeny of mitochondrial COI sequences revealed a significant (8.14%) genetic differentiation between the Argentinean and Paraguayan populations, which appeared to have diverged between the mid Miocene and early Pliocene. Altogether, toxinological and genetic evidence indicate that T. trivitattus populations from Paraguay and Argentina correspond to distinct, unique cryptic species, and suggest that further venom and taxonomic diversity exists in synanthropic southern South American Tityus than previously thought., Author summary Scorpionism (the medical consequence of scorpion stings in humans) is a neglected health problem in tropical and subtropical areas associated with poverty. This study is the first to compare venoms among core (Argentinean) and peripheral (Paraguayan) populations of the noxious Tityus trivittatus, the most medically important scorpion in the southernmost section of South America. The work demonstrated the lethality of the venom of urban populations of T. trivittatus in Paraguay, where it has caused severe cases in children. We obtained data indicating that there are significant differences in venom composition and function, and also recognition by therapeutic antivenoms available in the region, among these Argentinean and Paraguayan scorpion populations which historically have been assigned to the same species. Our genetic study revealed that in fact these two populations diverged between ~15–5 Million years ago, indicating they are distinct species. These results indicate that southern South American scorpions in the genus Tityus which co-distribute with humans are more diverse in terms of their venoms and species composition than previously thought, and that further studies are warranted to design more effective therapeutic tools against scorpionism in the region to tackle such diversity. more...

Scorpions of the Neotropical genus Tityus are responsible for most severe envenomations in the Caribbean, South America, and Lower Central America (LCA). Although Tityus is taxonomically complex, contains high toxin polymorphism, and produces variable clinical manifestations, treatment is limited to antivenoms produced against species with restricted distributions. In this study, we explored the compositional and antigenic diversity of Tityus venoms to provide improved guidelines for the use of available antivenoms at a broader geographic scale. We used immunoblotting, competitive ELISA, and in vivo studies to compare reactivity against commercial antivenoms from Brazil, Venezuela, and Mexico, as well as MALDI-TOF mass spectrometry, cDNA sequencing, and phylogenetic analyses to assess venom sodium channel-active toxin (NaTx) content from medically important Tityus populations inhabiting Brazil, Colombia, Costa Rica, Ecuador, Panama, Trinidad and Tobago, and Venezuela. Additionally, we raised rabbit antibodies against Tityus venoms from LCA to test for cross-reactivity with congeneric species. The results suggest that Tityus spp. possess high venom antigenic diversity, underlying the existence of four toxinological regions in Tropical America, based on venom composition and immunochemical criteria: LCA/Colombia/Amazonia (Region I), Venezuela (Region II), southeast South America (Region III), and a fourth region encompassing species related to toxinologically divergent Tityus cerroazul. Importantly, our molecular and cross-reactivity results highlight the need for new antivenoms against species inhabiting Region I, where scorpions may produce venoms that are not significantly reactive against available antivenoms UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) more...

Scorpion toxins are thought to have originated from ancestral housekeeping genes that underwent diversification and neofunctionalization, as a result of positive selection. Our understanding of the evolutionary origin of these peptides is hindered by the patchiness of existing taxonomic sampling. While recent studies have shown phylogenetic inertia in some scorpion toxins at higher systematic levels, evolutionary dynamics of toxins among closely related taxa remain unexplored. In this study, we used new and previously published transcriptomic resources to assess evolutionary relationships of closely related scorpions from the family Hadruridae and their toxins. In addition, we surveyed the incidence of scorpine-like peptides (SLP, a type of potassium channel toxin), which were previously known from 21 scorpion species. We demonstrate that scorpine-like peptides exhibit gene duplications. Our molecular analyses demonstrate that only eight sites of two SLP copies found in scorpions are evolving under positive selection, with more sites evolving under negative selection, in contrast to previous findings. These results show evolutionary conservation in toxin diversity at shallow taxonomic scale. more...

Over the past ten years, research into students' emotions in educational environments has increased. Although researchers have called for more studies that rely on objective measures of emotional experience, limitations on utilizing multi-modal data sources exist. Studies of emotion and emotional regulation in classrooms traditionally rely on survey instruments, experience-sampling, artifacts, interviews, or observational procedures. These methods, while valuable, are mainly dependent on participant or observer subjectivity and is limited in its authentic measurement of students' real-time performance to a classroom activity or task. The latter, in particular, poses a stumbling block to many scholars seeking to objectively measure emotions and other related measures in the classroom, in real-time. The purpose of this work is to present a protocol to experimentally study students' real-time responses to exam experiences during an authentic assessment situation. For this, a team of educational psychologists, engineers, and engineering education researchers designed an experimental protocol that retained the limits required for accurate physiological sensor measurement, best-practices of salivary collection, and an authentic testing environment. In particular, existing studies that rely on physiological sensors are conducted in experimental environments that are disconnected from educational settings (e.g., Trier Stress Test), detached in time (e.g., before or after a task), or introduce analysis error (e.g., use of sensors in environments where students are likely to move). This limits our understanding of students' real-time responses to classroom activities and tasks. Furthermore, recent research has called for more considerations to be covered around issues of recruitment, replicability, validity, setups, data cleaning, preliminary analysis, and particular circumstances (e.g., adding a variable in the experimental design) in academic emotions research that relies on multi-modal approaches. more...

Typhoid fever is endemic across sub-Saharan Africa. However, estimates of the burden of typhoid are undermined by insufficient blood volumes and lack of sensitivity of blood culture. Here, we aimed to address this limitation by exploiting pre-enrichment culture followed by PCR, alongside routine blood culture to improve typhoid case detection. We carried out a prospective diagnostic cohort study and enrolled children (aged 0–4 years) with non-specific febrile disease admitted to a tertiary hospital in Blantyre, Malawi from August 2014 to July 2016. Blood was collected for culture (BC) and real-time PCR after a pre-enrichment culture in tryptone soy broth and ox-bile. DNA was subjected to PCR for invA (Pan-Salmonella), staG (S. Typhi), and fliC (S. Typhimurium) genes. A positive PCR was defined as invA plus either staG or fliC (CT, Author summary There are increasing reports of typhoid fever epidemics in sub-Saharan Africa frequently affecting young adults and children aged between 5 and 16 years. In Asia where typhoid is hyperendemic, children aged 0 to 4 years also have a high burden of typhoid fever. Diagnosis of typhoid in young children is particularly a challenge because collection of adequate blood sample for testing is not always possible and the Salmonella bacterial load is low. Established methods of diagnosis such as blood culture and serology have low sensitivity. This study has used a combination of blood culture and pre-enrichment culture followed by PCR to improve ascertainment of the burden of both nontyphoidal Salmonella disease and typhoid fever in Malawian children, aged 0 to 4 years. We found that diagnosis with blood culture and pre-enrichment culture followed by PCR together added 94% more of nontyphoidal Salmonella and 62% more of Salmonella Typhi than blood culture alone. Where blood culture was negative but Salmonella-specific PCR was positive we have validated our results using Haemolysin (STY1498)-based serology. There are ongoing typhoid vaccine efficacy trials in Africa and Asia. The findings from this study will inform future estimates of vaccine effectiveness. more...

Divergent thinking can approximate creative potential of individuals and provide a valid way to understand the creative thinking process and creative development. Still, little is known about how the primary factors that make up divergent thinking—fluency, flexibility, and originality—develop during the early stages of adolescence. The dual pathway model suggests that creativity can emerge from both persistence and cognitive flexibility pathways. This study addresses current gaps about this theory, and tests the dual pathway model at the level of both creative ideation tasks and developmental change across time using the random intercepts cross-lagged panel model. That model controls for the autoregression effect of prior level on subsequent score as well as the effect of one factor on change in another. The results suggest that originality and fluency remain relatively stable from Grades 6–8, while flexibility increases from Grade 7–8. Within each wave, fluency showed the only positive relation with originality, suggesting the persistence pathway may be primary during early adolescence. Neither pathway explained developmental change. Originality influenced increase in flexibility and fluency, and that increase flexibility influenced further increase in fluency. Originality contributed to higher levels of creative illustration, creative self-efficacy, and creative self-concept. Fluency led to higher levels of creative metacognition. Developing ideas that are high in originality requires effort, time, practice, and strategy across different contexts. Formal learning opportunities to develop affect and skills for originality in ideas may converge with developmental advantages for creative potential in early adolescence, supporting students’ self-beliefs, metacognition, and cognition related to creativity. more...

Objectives Population mixing patterns can greatly inform allocation of HIV prevention interventions such as treatment as prevention or preexposure prophylaxis. Characterizing contact patterns among subgroups can help identify the specific combinations of contact expected to result in the greatest number of new infections. Setting Baseline data from an intervention to reduce HIV-related risk behaviors in male persons who inject drugs (PWID) in the Northern Vietnamese province of Thai Nguyen were used for the analysis. Methods Egocentric network data were provided by PWID who reported any drug-injection equipment sharing in the previous 3 months. Age-dependent mixing was assessed to explore its epidemiological implications on risk of HIV transmission risk (among those HIV-infected) and HIV acquisition risk (among those not infected) in PWID. Results A total of 1139 PWID collectively reported 2070 equipment-sharing partnerships in the previous 3 months. Mixing by age identified the 30-34 and 35-39 years age groups as the groups from whom the largest number of new infections was transmitted, making them primary targets for treatment as prevention. Among the uninfected, 25-29, 30-35, and 35-39 years age groups had the highest HIV acquisition rate, making them the primary targets for preexposure prophylaxis. Conclusions Collection and analysis of contact patterns in PWID is feasible and can greatly inform infectious disease dynamics and targeting of appropriate interventions. Results presented also provide much needed empirical data on mixing to improve mathematical models of disease transmission in this population. more...

A widespread Mesobuthus caucasicus complex, which includes some of the most common scorpions found from the Caucasus to China, is revised for the first time based on new extensive collections from Central Asia, using both morphological and DNA marker data. Mesobuthus caucasicus (Nordmann, 1840), s.str. is restricted to the Caucasus Mts. Four taxa are elevated to species rank: M. fuscus (Birula, 1897) (Tajikistan), M. intermedius (Birula, 1897) (Tajikistan), M. kaznakovi (Birula, 1904) (Tajikistan, Uzbekistan), and M. parthorum (Pocock, 1889) (Afghanistan, Iran, Turkmenistan). Six new species are described: M. brutus sp. n. (Iran), M. elenae sp. n. (Tajikistan, Uzbekistan), M. gorelovi sp. n. (Kazakhstan, Turkmenistan, Uzbekistan), M. kreuzbergi sp. n. (Tajikistan, Uzbekistan), M. mischi sp. n. (Afghanistan), and M. nenilini sp. n. (Uzbekistan). The most common species in Central Asia is a psammophilic Mesobuthus gorelovi sp. n., widespread through lowland sand deserts across Turkmenistan (Karakum), Uzbekistan (Kizylkum), and Kazakhstan (north to Baigakum and Moyinkum). A key to all studied species is provided. A DNA phylogeny based on COI and 16S rRNA markers is presented including nine Central Asian species (M. elenae sp. n., M. fuscus, M. gorelovi sp. n., M. intermedius, M. kaznakovi, M. kreuzbergi sp. n., M. mischi sp. n., M. nenilini sp. n., and M. parthorum) and M. caucasicus from Turkey. A deep phylogenetic diversity across Central Asia is revealed. Historical biogeographic scenarios for this scorpion group are discussed, including fragmentation in mountain valleys and expansion across sand deserts in Central Asia. The monotypic scorpion genus Afghanobuthus Lourenco, 2005 and its single species A. naumanni Lourenco, 2005, from Afghanistan, are demonstrated to be junior synonyms, respectively, of Mesobuthus Vachon, 1950, and M. parthorum (Pocock, 1889) from the same area. more...

Aim Phylogeographical studies in the Mojave and Sonoran deserts often find genetic discontinuities that pre-date the Pleistocene. A recent synthesis of phylogeographical data, called the Mojave Assembly Model, provides a hypothesis for the historical assembly of these desert biotas but does not adequately capture the complexity of pre-Pleistocene vicariance events. We tested this model and assessed pre-Pleistocene divergences by exploring the phylogeography of the Aphonopelma mojave group, which is composed of turret-building tarantula species from the Mojave and Sonoran deserts. Location Mojave and Sonoran deserts, south-western USA. Methods We augmented the sampling from a previous study by sequencing mitochondrial DNA (COI) from new material of the A. mojave group. We used phylogenetic and network analyses to identify clades and a molecular clock and lineages-through-time plots (LTT plots) to explore the timing and tempo of diversification. We tested for demographic expansion using neutrality tests and mismatch distributions. Species distribution models (SDMs) were constructed to compare current suitable habitat to that at the Last Glacial Maximum (LGM). Results Phylogenetic, network and molecular-clock analyses identified six major clades that probably diverged during the late Miocene. The rate of diversification appears to have slowed during the Pliocene. Most clades exhibit signals of recent demographic expansion. SDMs predicted that suitable habitat shifted south and to lower elevations during the LGM. Main conclusions Phylogeographical analyses suggest that the A. mojave group experienced a burst of diversification in the late Miocene, followed by population expansions during the Pleistocene. Six major clades with origins in the late Miocene cannot be adequately explained by the Mojave Assembly Model. We propose the novel hypothesis that Miocene extensional tectonics caused populations to diverge in allopatry by producing low-elevation habitat barriers. Geological models, such as kinematic reconstructions, provide an ideal but underutilized framework for testing biogeographical hypotheses in these deserts and the wider Basin and Range Province. more...

Morphologically conserved taxa such as scorpions represent a challenge to delimit. We recently discovered populations of scorpions in the genus Kovarikia Soleglad, Fet & Graham, 2014 on two isolated mountain ranges in southern California. We generated genome-wide single nucleotide polymorphism data and used Bayes factors species delimitation to compare alternative species delimitation scenarios which variously placed scorpions from the two localities with geographically adjacent species or into separate lineages. We also estimated a time-calibrated phylogeny of Kovarikia and examined and compared the morphology of preserved specimens from across its distribution. Genetic results strongly support the distinction of two new lineages, which we describe and name here. Morphology among the species of Kovarikia was relatively conserved, despite deep genetic divergences, consistent with recent studies of stenotopic scorpions with limited vagility. Phylogeographic structure discovered in several previously described species also suggests additional cryptic species are probably present in the genus. more...

National statistical agencies around the world publish tabular summaries based on combined employer-employee (ER-EE) data. The privacy of both individuals and business establishments that feature in these data are protected by law in most countries. These data are currently released using a variety of statistical disclosure limitation (SDL) techniques that do not reveal the exact characteristics of particular employers and employees, but lack provable privacy guarantees limiting inferential disclosures. In this work, we present novel algorithms for releasing tabular summaries of linked ER-EE data with formal, provable guarantees of privacy. We show that state-of-the-art differentially private algorithms add too much noise for the output to be useful. Instead, we identify the privacy requirements mandated by current interpretations of the relevant laws, and formalize them using the Pufferfish framework. We then develop new privacy definitions that are customized to ER-EE data and satisfy the statutory privacy requirements. We implement the experiments in this paper on production data gathered by the U.S. Census Bureau. An empirical evaluation of utility for these data shows that for reasonable values of the privacy-loss parameter e≥ 1, the additive error introduced by our provably private algorithms is comparable, and in some cases better, than the error introduced by existing SDL techniques that have no provable privacy guarantees. For some complex queries currently published, however, our algorithms do not have utility comparable to the existing traditional SDL algorithms. Those queries are fodder for future research. more...

Research progress on the order Solifugae, commonly known as camel spiders, has been hindered by challenges inherent in collecting these fast-moving, nocturnal predators. Recently, pitfall trapping combined with artificial light lures showed promise for improving capture rates, but the hypothesis that camel spiders are attracted to light traps (positive phototaxis) has never been tested. We constructed short pitfall trap arrays with and without lights across the Mojave Desert to test the light attraction hypothesis. Nearly all camel spiders we collected were found in traps with suspended lights, lending strong support for positive phototaxis. Distance from the lights within trap arrays does not appear to be correlated with the success of individual pitfall traps. Excitingly, our short pitfall light arrays, or Caterpillar light traps, were relatively easy to install and yielded an order of magnitude more camel spiders per effort hour than previously reported techniques. more...