Hybrid speciation driven by multilocus introgression of ecological traits.

Hybridization allows adaptations to be shared among lineages and may trigger the evolution of new species1,2. However, convincing examples of homoploid hybrid speciation remain rare because it is challenging to demonstrate that hybridization was crucial in generating reproductive isolation3. Here we combine population genomic analysis with quantitative trait locus mapping of species-specific traits to examine a case of hybrid speciation in Heliconius butterflies. We show that Heliconius elevatus is a hybrid species that is sympatric with both parents and has persisted as an independently evolving lineage for at least 180,000 years. This is despite pervasive and ongoing gene flow with one parent, Heliconius pardalinus, which homogenizes 99% of their genomes. The remaining 1% introgressed from the other parent, Heliconius melpomene, and is scattered widely across the H. elevatus genome in islands of divergence from H. pardalinus. These islands contain multiple traits that are under disruptive selection, including colour pattern, wing shape, host plant preference, sex pheromones and mate choice. Collectively, these traits place H. elevatus on its own adaptive peak and permit coexistence with both parents. Our results show that speciation was driven by introgression of ecological traits, and that speciation with gene flow is possible with a multilocus genetic architecture.

A global map of species at risk of extinction due to natural hazards.

An often-overlooked question of the biodiversity crisis is how natural hazards contribute to species extinction risk. To address this issue, we explored how four natural hazards, earthquakes, hurricanes, tsunamis, and volcanoes, overlapped with the distribution ranges of amphibians, birds, mammals, and reptiles that have either narrow distributions or populations with few mature individuals. To assess which species are at risk from these natural hazards, we combined the frequency and magnitude of each natural hazard to estimate their impact. We considered species at risk if they overlapped with regions where any of the four natural hazards historically occurred (n = 3,722). Those species with at least a quarter of their range subjected to a high relative impact were considered at high risk (n = 2,001) of extinction due to natural hazards. In total, 834 reptiles, 617 amphibians, 302 birds, and 248 mammals were at high risk and they were mainly distributed on islands and in the tropics. Hurricanes (n = 983) and earthquakes (n = 868) affected most species, while tsunamis (n = 272), and volcanoes (n = 171) affected considerably fewer. The region with the highest number of species at high risk was the Pacific Ring of Fire, especially due to volcanoes, earthquakes, and tsunamis, while hurricane-related high-risk species were concentrated in the Caribbean Sea, Gulf of Mexico, and northwestern Pacific Ocean. Our study provides important information regarding the species at risk due to natural hazards and can help guide conservation attention and efforts to safeguard their survival.

Wing pattern diversity in Eunica butterflies (Nymphalidae: Biblidinae): phylogenetic analysis implies decoupled adaptive trends in dorsal sexual dimorphism and ventral eyespot evolution.

Butterfly eyespots are wing patterns reminiscent of vertebrate eyes, formed by concentric rings of contrastingly coloured scales. Eyespots are usually located close to the wing margin and often regarded as the single most conspicuous pattern element of butterfly wing colour displays. Recent efforts to understand the processes involved in the formation of eyespots have been driven mainly by evo-devo approaches focused on model species. However, patterns of change implied by phylogenetic relationships can also inform hypotheses about the underlying developmental mechanisms associated with the formation or disappearance of eyespots, and the limits of phenotypic diversity occurring in nature. Here we present a combined evidence phylogenetic hypothesis for the genus Eunica, a prominent member of diverse Neotropical butterfly communities, that features notable variation among species in eyespot patterns on the ventral hind wing surface. The data matrix consists of one mitochondrial gene region (COI), four nuclear gene regions (GAPDH, RPS5, EF1a and Wingless) and 68 morphological characters. A combined cladistic analysis with all the characters concatenated produced a single most parsimonious tree that, although fully resolved, includes many nodes with modest branch support. The phylogenetic hypothesis presented corroborates a previously proposed morphological trend leading to the loss of eyespots, together with an increase in the size of the conserved eyespots, relative to outgroup taxa. Furthermore, wing colour pattern dimorphism and the presence of androconia suggest that the most remarkable instances of sexual dimorphism are present in the species of Eunica with the most derived eyespot patterns, and are in most cases accompanied by autapomorphic combinations of scent scales and "hair pencils". We discuss natural and sexual selection as potential adaptive explanations for dorsal and ventral wing patterns.

A systematic review of biologically-informed deep learning models for cancer: fundamental trends for encoding and interpreting oncology data.

BACKGROUND: There is an increasing interest in the use of Deep Learning (DL) based methods as a supporting analytical framework in oncology. However, most direct applications of DL will deliver models with limited transparency and explainability, which constrain their deployment in biomedical settings. METHODS: This systematic review discusses DL models used to support inference in cancer biology with a particular emphasis on multi-omics analysis. It focuses on how existing models address the need for better dialogue with prior knowledge, biological plausibility and interpretability, fundamental properties in the biomedical domain. For this, we retrieved and analyzed 42 studies focusing on emerging architectural and methodological advances, the encoding of biological domain knowledge and the integration of explainability methods. RESULTS: We discuss the recent evolutionary arch of DL models in the direction of integrating prior biological relational and network knowledge to support better generalisation (e.g. pathways or Protein-Protein-Interaction networks) and interpretability. This represents a fundamental functional shift towards models which can integrate mechanistic and statistical inference aspects. We introduce a concept of bio-centric interpretability and according to its taxonomy, we discuss representational methodologies for the integration of domain prior knowledge in such models. CONCLUSIONS: The paper provides a critical outlook into contemporary methods for explainability and interpretability used in DL for cancer. The analysis points in the direction of a convergence between encoding prior knowledge and improved interpretability. We introduce bio-centric interpretability which is an important step towards formalisation of biological interpretability of DL models and developing methods that are less problem- or application-specific.

Mutualistic interactions shape global spatial congruence and climatic niche evolution in Neotropical mimetic butterflies.

Understanding the mechanisms underlying species distributions and coexistence is both a priority and a challenge for biodiversity hotspots such as the Neotropics. Here, we highlight that Müllerian mimicry, where defended prey species display similar warning signals, is key to the maintenance of biodiversity in the c. 400 species of the Neotropical butterfly tribe Ithomiini (Nymphalidae: Danainae). We show that mimicry drives large-scale spatial association among phenotypically similar species, providing new empirical evidence for the validity of Müller's model at a macroecological scale. Additionally, we show that mimetic interactions drive the evolutionary convergence of species climatic niche, thereby strengthening the co-occurrence of co-mimetic species. This study provides new insights into the importance of mutualistic interactions in shaping both niche evolution and species assemblages at large spatial scales. Critically, in the context of climate change, our results highlight the vulnerability to extinction cascades of such adaptively assembled communities tied by positive interactions.

Comparing the Cubic and Tetragonal Phases of MAPbI3 at Room Temperature.

Stability and maintenance of the crystal structure are the main drawbacks of the application of organic-inorganic perovskites in photovoltaic devices. The ΔT = 62 K robust shift of the structural phase transition observed here allows us to conduct a comprehensive study at room temperature of the tetragonal versus cubic phase on MAPbI3. The absence of the shift in the cubic transition for all-inorganic CsPbI3 samples confirms the importance of both orientation and dynamics of the organic cations. Our results provide a unique opportunity to evaluate the physical properties of both cubic and tetragonal phases of MAPbI3 at the same temperature, eliminating different phonon effects as possible causes for different properties. Besides higher electrical resistivity, the perovskite cubic phase presents a faster charge carrier lifetime than the tetragonal phase and partial PL quenching, pointing toward increased trap-assisted nonradiative recombination. The light absorption coefficient in the cubic phase is larger than the absorption in the tetragonal phase in the green region.

Meta-analysis informed machine learning: Supporting cytokine storm detection during CAR-T cell Therapy.

Cytokine release syndrome (CRS), also known as cytokine storm, is one of the most consequential adverse effects of chimeric antigen receptor therapies that have shown otherwise promising results in cancer treatment. When emerging, CRS could be identified by the analysis of specific cytokine and chemokine profiles that tend to exhibit similarities across patients. In this paper, we exploit these similarities using machine learning algorithms and set out to pioneer a meta-review informed method for the identification of CRS based on specific cytokine peak concentrations and evidence from previous clinical studies. To this end we also address a widespread challenge of the applicability of machine learning in general: reduced training data availability. We do so by augmenting available (but often insufficient) patient cytokine concentrations with statistical knowledge extracted from domain literature. We argue that such methods could support clinicians in analyzing suspect cytokine profiles by matching them against the said CRS knowledge from past clinical studies, with the ultimate aim of swift CRS diagnosis. We evaluate our proposed methods under several design choices, achieving performance of more than 90% in terms of CRS identification accuracy, and showing that many of our choices outperform a purely data-driven alternative. During evaluation with real-world CRS clinical data, we emphasize the potential of our proposed method of producing interpretable results, in addition to being effective in identifying the onset of cytokine storm.

Patient attrition in Molecular Tumour Boards: a systematic review.

BACKGROUND: Molecular Tumour Boards (MTBs) were created with the purpose of supporting clinical decision-making within precision medicine. Though in use globally, reporting on these meetings often focuses on the small percentages of patients that receive treatment via this process and are less likely to report on, and assess, patients who do not receive treatment. METHODS: A literature review was performed to understand patient attrition within MTBs and barriers to patients receiving treatment. A total of 51 papers were reviewed spanning a 6-year period from 11 different countries. RESULTS: In total, 20% of patients received treatment through the MTB process. Of those that did not receive treatment, the main reasons were no mutations identified (27%), no actionable mutations (22%) and clinical deterioration (15%). However, data were often incomplete due to inconsistent reporting of MTBs with only 55% reporting on patients having no mutations, 55% reporting on the presence of actionable mutations with no treatment options and 59% reporting on clinical deterioration. DISCUSSION: As patient attrition in MTBs is an issue which is very rarely alluded to in reporting, more transparent reporting is needed to understand barriers to treatment and integration of new technologies is required to process increasing omic and treatment data.

Phylogenetic systematics of Yphthimoides Forster, 1964 and related taxa, with notes on the biogeographical history of Yphthimoides species.

Species losses are increasing and may have an impact on our understanding of patterns of evolutionary pathways and phylogenetic relationships among the groups being lost. The knowledge of such patterns can contribute to preventing future losses by identifying which lineages have higher or lower diversification rates, thus informing conservation strategies. Recent years have seen a significant growth in studies of butterfly systematics, allowing a better understanding of evolutionary relationships among most groups and revealing significant taxonomic chaos in several groups. One of the latter groups is the nymphalid subtribe Euptychiina (Satyrinae), which has been shown to include a number of non-monophyletic genera based on recent molecular phylogenetic analyses. Among others, these genera include Yphthimoides, which is widespread throughout the Neotropical region but particularly diverse in the southeastern Neotropics, and a pair of related genera, Pharneuptychia Forster, 1964 and Moneuptychia Forster, 1964. Using molecular data, this study scope and aims were to provide a phylogenetic hypothesis that corroborates Yphthimoides as presently conceived being non-monophyletic, a result reinforced by a comparative study of the male genitalic morphology. Our results also show that Pharneuptychia and Moneuptychia, plus a species misplaced elsewhere in the Euptychiina, Euptychoides castrensis (Schaus, 1902), form a well supported clade, and that the latter 'species' is a complex of cryptic species. We therefore propose a number of taxonomic rearrangements in the present work to resolve these issues: Yphthimoides eriphule (A. Butler, 1867) will be moved to a new genus; Y. affinis (A. Butler, 1867), Y. maepius (Godart, [1824]), Y. mimula (Hayward, 1954), Y. neomaenas (Hayward, 1967) and Y. mythra (Weymer, 1911) are being transferred to Malaveria Viloria & Benmesbah, 2021; Pharneuptychia innocentia (Godart, [1824]) will be moved to another genus to be described; and Euptychoides castrensis, Pharneuptychia romanina (Bryk, 1953) and Yphthimoides viviana (Romieux, 1927) are being moved to Moneuptychia. The dating of divergences points to a split between the ancestral lineage of Yphthimoides and its sister group, Carminda Ebert and Dias, inDias 1998, during the last half of the Miocene, around 11.86 Mya, and to the diversification of the Pharneuptychia during the same time 11.35 (±3.52) Mya. Biogeographic analysis showed that the most recent common ancestor of Yphthimoides started to diversify either in the the Brazilian Cerrado savannas or in a combined area of Cerrado and South Atlantic Forest, with a possible change in the ancestral habitat of Carminda. Furthermore, ancestral character mapping favors a savanna origin hypothesis over a forest origin hypothesis.

Chikungunya in Brazil: An epidemic of high cost for private healthcare, 2017.

OBJECTIVE: We evaluated the impact of direct and indirect medical costs incurred through chikungunya infections in patients treated in Fortaleza, Brazil. METHODS: Cross-sectional study about the cost of illness. The valuation method of medical costs was based on the micro-costing approach (bottom-up). The study was carried out in a large general hospital of the private health network. The study population consisted of patients treated as suspected cases of chikungunya and hospital professionals who applied for sick leave due to chikungunya. RESULTS: In 2017, there were 2683 patients treated at this hospital who incurred an estimated cost of $383,514.40. From this amount, $174,322.91 (45.5%) were expended on emergency care, $194,700.59 (50.8%) on hospitalisations. 123 hospital professionals were infected with chikungunya and sick leave duration ranged between 1 and 19 days. Health professionals generated 746 days of absence and an amount of $14,490.90 due to absenteeism from work related to chikungunya. 31 symptoms were reported, especially arthralgia (91.1%) and fever (79.4%). There was a predominance of females (58.8%) and the age group of 20-39 years (42.1%). CONCLUSION: The average cost of admissions was over $2400. Considering the epidemic potential of chikungunya, our data indicate the huge economic burden of this disease to healthcare units in the presence of epidemics. Economic factors, added to the loss of life and the consequences of chronic chikungunya, make this disease a real scourge for countries with fewer material resources.

Insect decline in Brazil: an appraisal of current evidence.

Recent reviews of data on worldwide insect decline include almost no information on Brazil. We gathered evidence from literature searches and a survey sent to researchers, to which 96 replied and 56 provided information and publications. We present 75 instances of trends recorded over an average span of 11 years for aquatic and 22 years for terrestrial insects. These include time-replicated samples and expert opinion based on long-term local collections. Most terrestrial data are for butterflies, bees and scarab beetles. Aquatic studies include several insect orders, usually sorted to genus or family. Terrestrial insects showed significantly more cases of declines than increases, both in abundance (17 : 3) and in diversity (11 : 1). In aquatic cases, no tendency was detected in abundance (2 : 2) or diversity (3 : 4), not counting cases with no trend. Differences in these results among habitats may be due to the shorter span and less change in environmental conditions in the aquatic surveys, which included sites already degraded before sampling. We offer guidelines for future long-term assessments, including resampling of legacy collection sites.

Comparative bioavailability study with two sodium valproate tablet formulations administered under fasting conditions in healthy subjects.

AIM: To assess the bioequivalence of two sodium valproate formulations in healthy subjects of both sexes. MATERIALS AND METHODS: The study was conducted using an open, randomized, two-period crossover design with a 2-week washout interval. Plasma samples were obtained over a 96-hour period. Plasma concentrations of valproate were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC/MS) with negative ion electrospray ionization. From the sodium valproate plasma concentration vs. time curves, the following pharmacokinetic parameters were obtained Cmax, AUC, tmax, Ke, and T1/2. RESULTS: The geometric mean with corresponding 90% confidence interval for test/reference percent ratios were 104.43% (90% CI 100.42 - 108.61%) for Cmax, 98.11% (90% CI = 94.66 - 101.70%) for AUClast, and 96.71% (90% CI = 92.97 - 100.60%) for AUC0-inf. CONCLUSION: Since the 90% CI for Cmax and AUClast ratios were all inside the 80 - 125% interval proposed by the US Food and Drug Administration Agency (FDA), it was concluded that the new sodium valproate formulation (epilenil 500-mg coated tablet) without food elaborated by Biolab Sanus Farmaceutica Ltda is bioequivalent to depakene formulation for both the rate and the extent of absorption.

Fatal Outcome of Chikungunya Virus Infection in Brazil.

BACKGROUND: Chikungunya virus (CHIKV) emerged in the Americas in 2013 and has caused approximately 2.1 million cases and >600 deaths. A retrospective investigation was undertaken to describe clinical, epidemiological, and viral genomic features associated with deaths caused by CHIKV in Ceará state, northeast Brazil. METHODS: Sera, cerebrospinal fluid (CSF), and tissue samples from 100 fatal cases with suspected arbovirus infection were tested for CHIKV, dengue virus (DENV), and Zika virus (ZIKV). Clinical, epidemiological, and death reports were obtained for patients with confirmed CHIKV infection. Logistic regression analysis was undertaken to identify independent factors associated with risk of death during CHIKV infection. Phylogenetic analysis was conducted using whole genomes from a subset of cases. RESULTS: Sixty-eight fatal cases had CHIKV infection confirmed by reverse-transcription quantitative polymerase chain reaction (52.9%), viral antigen (41.1%), and/or specific immunoglobulin M (63.2%). Co-detection of CHIKV with DENV was found in 22% of fatal cases, ZIKV in 2.9%, and DENV and ZIKV in 1.5%. A total of 39 CHIKV deaths presented with neurological signs and symptoms, and CHIKV-RNA was found in the CSF of 92.3% of these patients. Fatal outcomes were associated with irreversible multiple organ dysfunction syndrome. Patients with diabetes appear to die at a higher frequency during the subacute phase. Genetic analysis showed circulation of 2 CHIKV East-Central-South African (ECSA) lineages in Ceará and revealed no unique virus genomic mutation associated with fatal outcome. CONCLUSIONS: The investigation of the largest cross-sectional cohort of CHIKV deaths to date reveals that CHIKV-ECSA strains can cause death in individuals from both risk and nonrisk groups, including young adults.

North-south and climate-landscape-associated pattern of population structure for the Atlantic Forest White Morpho butterflies.

Atlantic Forest White Morpho butterflies, currently classified as Morpho epistrophus and M. iphitus, are endemic to the Atlantic Forest, where they are widely distributed throughout heterogeneous environmental conditions. Studies with endemic butterflies allow to elucidate questions on both patterns of diversity distribution and current and past processes acting on insect groups in this biodiversity hotspot. In the present study, we characterized one mtDNA marker (COI sequences) and developed 11 polymorphic loci of microsatellite for 22 sampling locations distributed throughout the entire Atlantic Forest domain. We investigated both the taxonomic limits of taxa classified as White Morpho and the structure and distribution of the genetic diversity throughout their populations. Genetic markers and distribution data failed to identify species diversification, population structure, or isolation among subpopulations attributed to different taxa proposed for the White Morpho, suggesting that the current distinction between two species is unreasonable. The Bayesian coalescent tree based on COI sequences also failed to recover monophyletic clades for the putative species, and pointed instead to a north-south oriented pattern of genetic structure, with the northern clade coalescing later than the southern clade. Northern samples also showed more intragroup structure than southern samples based on mtDNA data. Clustering tests based on microsatellites indicated the existence of three genetic clusters, with turnover between the states of Paraná and São Paulo. The north-south pattern found for the White Morpho populations is showed for the first time to a endemic AF insect and coincides with the two different bioclimatic domains previously described for vertebrates and plants. Population structure observed for these butterflies is related to climate- and landscape-associated variables, mainly precipitation and elevation.

Gas6 drives Zika virus-induced neurological complications in humans and congenital syndrome in immunocompetent mice.

Zika virus (ZIKV) has the ability to cross placental and brain barriers, causing congenital malformations in neonates and neurological disorders in adults. However, the pathogenic mechanisms of ZIKV-induced neurological complications in adults and congenital malformations are still not fully understood. Gas6 is a soluble TAM receptor ligand able to promote flavivirus internalization and downregulation of immune responses. Here we demonstrate that there is a correlation between ZIKV neurological complications with higher Gas6 levels and the downregulation of genes associated with anti-viral response, as type I IFN due to Socs1 upregulation. Also, Gas6 gamma-carboxylation is essential for ZIKV invasion and replication in monocytes, the main source of this protein, which was inhibited by warfarin. Conversely, Gas6 facilitates ZIKV replication in adult immunocompetent mice and enabled susceptibility to transplacental infection. Our data indicate that ZIKV promotes the upregulation of its ligand Gas6, which contributes to viral infectivity and drives the development of severe adverse outcomes during ZIKV infection.

Use of species delimitation approaches to tackle the cryptic diversity of an assemblage of high Andean butterflies (Lepidoptera: Papilionoidea).

Cryptic biological diversity has generated ambiguity in taxonomic and evolutionary studies. Single-locus methods and other approaches for species delimitation are useful for addressing this challenge, enabling the practical processing of large numbers of samples for identification and inventory purposes. This study analyzed an assemblage of high Andean butterflies using DNA barcoding and compared the identifications based on the current morphological taxonomy with three methods of species delimitation (automatic barcode gap discovery, generalized mixed Yule coalescent model, and Poisson tree processes). Sixteen potential cryptic species were recognized using these three methods, representing a net richness increase of 11.3% in the assemblage. A well-studied taxon of the genus Vanessa, which has a wide geographical distribution, appeared with the potential cryptic species that had a higher genetic differentiation at the local level than at the continental level. The analyses were useful for identifying the potential cryptic species in Pedaliodes and Forsterinaria complexes, which also show differentiation along altitudinal and latitudinal gradients. This genetic assessment of an entire assemblage of high Andean butterflies (Papilionoidea) provides baseline information for future research in a region characterized by high rates of endemism and population isolation.

Host tree traits in pasture areas affect forest and pasture specialist epiphyte species differently.

PREMISE: Epiphytes have commensal relationships with their host trees. Besides the influence of tree traits, little has been discussed concerning the ecology of epiphytes in disturbed habitats (e.g., pasture). We herein tested whether the occurrences of pasture and forest specialist epiphytes in pastures are affected differently by tree traits. We hypothesized that (H1) the richness and abundance of generalist epiphytes would be positively associated with area availability; (H2) the richness and abundance of forest epiphyte species would be associated both with (H2.a) area availability and (H2.b) tree traits related to higher seed adherence, and/or (H2.c) less severe habitat (e.g., high humidity and more shade). METHODS: We sampled 9567 epiphyte individuals from 16 species on 759 scattered remnant trees. The epiphyte species were divided into two ecological groups: forest specialists and pasture specialists. We evaluated four host tree traits: two related to tree size (crown area and trunk diameter) and two related to habitat type (crown leaf density and bark rugosity). RESULTS: The richness and abundance of both pasture and forest specialists were positively related with tree size. However, the abundance of pasture specialists was negatively related with crown leaf density, whereas richness of forest epiphytes was positively related with bark rugosity. CONCLUSIONS: Large scattered trees tend to present higher richness and abundance of both pasture and forest specialist epiphytes compared to the smaller trees. However, high crown leaf density limits abundance of pasture specialist epiphytes, whereas rugose bark increases the richness of forest epiphytes.

The roles of hybridization and habitat fragmentation in the evolution of Brazil's enigmatic longwing butterflies, Heliconius nattereri and H. hermathena.

BACKGROUND: Heliconius butterflies are widely distributed across the Neotropics and have evolved a stunning array of wing color patterns that mediate Müllerian mimicry and mating behavior. Their rapid radiation has been strongly influenced by hybridization, which has created new species and allowed sharing of color patterning alleles between mimetic species pairs. While these processes have frequently been observed in widespread species with contiguous distributions, many Heliconius species inhabit patchy or rare habitats that may strongly influence the origin and spread of species and color patterns. Here, we assess the effects of historical population fragmentation and unique biology on the origins, genetic health, and color pattern evolution of two rare and sparsely distributed Brazilian butterflies, Heliconius hermathena and Heliconius nattereri. RESULTS: We assembled genomes and re-sequenced whole genomes of eight H. nattereri and 71 H. hermathena individuals. These species harbor little genetic diversity, skewed site frequency spectra, and high deleterious mutation loads consistent with recent population bottlenecks. Heliconius hermathena consists of discrete, strongly isolated populations that likely arose from a single population that dispersed after the last glacial maximum. Despite having a unique color pattern combination that suggested a hybrid origin, we found no genome-wide evidence that H. hermathena is a hybrid species. However, H. hermathena mimicry evolved via introgression, from co-mimetic Heliconius erato, of a small genomic region upstream of the color patterning gene cortex. CONCLUSIONS: Heliconius hermathena and H. nattereri population fragmentation, potentially driven by historical climate change and recent deforestation, has significantly reduced the genetic health of these rare species. Our results contribute to a growing body of evidence that introgression of color patterning alleles between co-mimetic species appears to be a general feature of Heliconius evolution.

Priors and Posteriors in Bayesian Timing of Divergence Analyses: The Age of Butterflies Revisited.

The need for robust estimates of times of divergence is essential for downstream analyses, yet assessing this robustness is still rare. We generated a time-calibrated genus-level phylogeny of butterflies (Papilionoidea), including 994 taxa, up to 10 gene fragments and an unprecedented set of 12 fossils and 10 host-plant node calibration points. We compared marginal priors and posterior distributions to assess the relative importance of the former on the latter. This approach revealed a strong influence of the set of priors on the root age but for most calibrated nodes posterior distributions shifted from the marginal prior, indicating significant information in the molecular data set. Using a very conservative approach we estimated an origin of butterflies at 107.6 Ma, approximately equivalent to the latest Early Cretaceous, with a credibility interval ranging from 89.5 Ma (mid Late Cretaceous) to 129.5 Ma (mid Early Cretaceous). In addition, we tested the effects of changing fossil calibration priors, tree prior, different sets of calibrations and different sampling fractions but our estimate remained robust to these alternative assumptions. With 994 genera, this tree provides a comprehensive source of secondary calibrations for studies on butterflies.

Seroprevalence, spatial dispersion and factors associated with flavivirus and chikungunha infection in a risk area: a population-based seroprevalence study in Brazil.

BACKGROUND: The State of Ceará, in Northeastern Brazil, suffers from a triple burden of arboviruses (dengue, Zika and chikungunya). We measured the seroprevalence of chikungunya, dengue and Zika and its associated factors in the population of Juazeiro do Norte, Southern Ceará State, Brazil. METHODS: A cross-sectional study of analytical and spatial analysis was performed to estimate the seroprevalence of dengue, Zika and chikungunya, in the year 2018. Participants were tested for IgM and IgG against these three viruses. Those with IgM and/or IgG positive tests results were considered positive. Poisson regression was used to analyze the factors associated with positive cases, in the same way that the spatial analysis of positive cases was performed to verify whether the cases were grouped. RESULTS: Of the 404 participants, 25.0% (103/404) were positive for CHIKV, 92.0% (373/404) for flavivirus (dengue or Zika) and of these, 37.9% (153/404) samples were classified as probable dengue infection. Of those who reported having had an arbovirus in the past, positive CHIKV cases had 58.7% arthralgia (PR = 4.31; 95% CI: 2.06-9.03; p = 0.000) mainly in the hands, ankles and feet. Age over 60 years had a positive association with cases of flavivirus (PR = 1.29; 95% CI: 1.09-1.54; p = 0.000). Fever, muscle pain, joint pain and skin rash were the most reported symptoms (46.1, 41.0, 38.3 and 28.41%, respectively). The positive cases of chikungunya and dengue or Zika were grouped in space and the city center was most affected area. CONCLUSIONS: Four years after the introduction of CHIKV, where DENV has been in circulation for over 30 years, 1/4 of the population has already been exposed, showing the extent of the epidemic. The measured prevalence was much higher than that reported by local epidemiological surveillance.