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Based on the nucleotide sequences of the mitochondrial genome (mitogenome) of specimens taken from two mussel species (Arcuatula senhousia and Mytilus coruscus), an investigation was performed by means of the complex approaches of the genomics, molecular phylogenetics, and evolutionary genetics. The mitogenome structure of studied mussels, like in many other invertebrates, appears to be much more variable than in vertebrates and includes changing gene order, duplications, and deletions, which were most frequent for tRNA genes; the mussel species' mitogenomes also have variable sizes. The results demonstrate some of the very important properties of protein polypeptides, such as hydrophobicity and its determination by the purine and pyrimidine nucleotide ratio. This fact might indirectly indicate the necessity of purifying natural selection for the support of polypeptide functionality. However, in accordance with the widely accepted and logical concept of natural cutoff selection for organisms living in nature, which explains its action against deleterious nucleotide substitutions in the nonsynonymous codons (mutations) and its holding of the active (effective) macromolecules of the polypeptides in a population, we were unable to get unambiguous evidence in favor of this concept in the current paper. Here, the phylogeny and systematics of mussel species from one of the largest taxons of bivalve mollusks are studied, the family known as Mytilidae. The phylogeny for Mytilidae (order Mytilida), which currently has no consensus in terms of systematics, is reconstructed using a data matrix of 26-27 mitogenomes. Initially, a set of 100 sequences from GenBank were downloaded and checked for their gender: whether they were female (F) or male (M) in origin. Our analysis of the new data confirms the known drastic differences between the F/M mitogenome lines in mussels. Phylogenetic reconstructions of the F-lines were performed using the combined set of genetic markers, reconstructing only protein-coding genes (PCGs), only rRNA + tRNA genes, and all genes. Additionally, the analysis includes the usage of nucleotide sequences composed of other data matrices, such as 20-68 mitogenome sequences. The time of divergence from MRCA, estimated via BEAST2, for Mytilidae is close to 293 Mya, suggesting that they originate in the Silurian Period. From all these data, a consensus for the phylogeny of the subfamily of Mytilinae and its systematics is suggested. In particular, the long-debated argument on mussel systematics was resolved as to whether Mytilidae, and the subfamily of Mytilinae, are monophyletic. The topology signal, which was strongly resolved in this paper and in the literature, has refuted the theory regarding the monophyly of Mytilinae.
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Evolução Molecular , Genoma Mitocondrial , Filogenia , Animais , Genoma Mitocondrial/genética , Mytilidae/genética , Mytilidae/classificação , RNA de Transferência/genética , Bivalves/genética , Bivalves/classificação , Mytilus/genética , Mytilus/classificaçãoRESUMO
Identifying along which lineages shifts in diversification rates occur is a central goal of comparative phylogenetics; these shifts may coincide with key evolutionary events such as the development of novel morphological characters, the acquisition of adaptive traits, polyploidization or other structural genomic changes, or dispersal to a new habitat and subsequent increase in environmental niche space. However, while multiple methods now exist to estimate diversification rates and identify shifts using phylogenetic topologies, the appropriate use and accuracy of these methods are hotly debated. Here we test whether five Bayesian methods-Bayesian Analysis of Macroevolutionary Mixtures (BAMM), two implementations of the Lineage-Specific Birth-Death-Shift model (LSBDS and PESTO), the approximate Multi-Type Birth-Death model (MTBD; implemented in BEAST2), and the Cladogenetic Diversification Rate Shift model (ClaDS2)-produce comparable results. We apply each of these methods to a set of 65 empirical time-calibrated phylogenies and compare inferences of speciation rate, extinction rate, and net diversification rate. We find that the five methods often infer different speciation, extinction, and net-diversification rates. Consequently, these different estimates may lead to different interpretations of the macroevolutionary dynamics. The different estimates can be attributed to fundamental differences among the compared models. Therefore, the inference of shifts in diversification rates is strongly method dependent. We advise biologists to apply multiple methods to test the robustness of the conclusions or to carefully select the method based on the validity of the underlying model assumptions to their particular empirical system.
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Accurate estimation of the dispersal velocity or speed of evolving organisms is no mean feat. In fact, existing probabilistic models in phylogeography or spatial population genetics generally do not provide an adequate framework to define velocity in a relevant manner. For instance, the very concept of instantaneous speed simply does not exist under one of the most popular approaches that models the evolution of spatial coordinates as Brownian trajectories running along a phylogeny [30]. Here, we introduce a new family of models - the so-called "Phylogenetic Integrated Velocity" (PIV) models - that use Gaussian processes to explicitly model the velocity of evolving lineages instead of focusing on the fluctuation of spatial coordinates over time. We describe the properties of these models and show an increased accuracy of velocity estimates compared to previous approaches. Analyses of West Nile virus data in the U.S.A. indicate that PIV models provide sensible predictions of the dispersal of evolving pathogens at a one-year time horizon. These results demonstrate the feasibility and relevance of predictive phylogeography in monitoring epidemics in time and space.
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Knowledge of the optical parameters of tumors is important for choosing the correct laser treatment parameters. In this paper, optical properties and refraction indices of breast tissue in healthy mice and a 4T1 model mimicking human breast cancer have been measured. A significant decrease in both the scattering and refractive index of tumor tissue has been observed. The change in tissue morphology has induced the change in the slope of the scattering spectrum. Thus, the light penetration depth into tumor has increased by almost 1.5-2 times in the near infrared "optical windows." Raman spectra have shown lower lipid content and higher protein content in tumor. The difference in the optical parameters of the tissues under study makes it possible to reliably differentiate them. The results may be useful for modeling the distribution of laser radiation in healthy tissues and cancers for deriving optimal irradiation conditions in photodynamic therapy.
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Fenômenos Ópticos , Análise Espectral Raman , Animais , Camundongos , Feminino , Humanos , Linhagem Celular Tumoral , Refratometria , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/radioterapia , Camundongos Endogâmicos BALB CRESUMO
We accurately reconstruct the Local Field Potential time series obtained from anesthetized and awake rats, both before and during CO 2 euthanasia. We apply the Eigensystem Realization Algorithm to identify an underlying linear dynamical system capable of generating the observed data. Time series exhibiting more intricate dynamics typically lead to systems of higher dimensions, offering a means to assess the complexity of the brain throughout various phases of the experiment. Our results indicate that anesthetized brains possess complexity levels similar to awake brains before CO 2 administration. This resemblance undergoes significant changes following euthanization, as signals from the awake brain display a more resilient complexity profile, implying a state of heightened neuronal activity or a last fight response during the euthanasia process. In contrast, anesthetized brains seem to enter a more subdued state early on. Our data-driven techniques can likely be applied to a broader range of electrophysiological recording modalities.
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Algoritmos , Encéfalo , Animais , Encéfalo/fisiologia , Ratos , Vigília/fisiologia , Eutanásia , Masculino , Eutanásia Animal/métodos , Dióxido de CarbonoRESUMO
In this article, we study the distance matrix as a representation of a phylogeny by way of hierarchical clustering. By defining a multivariate normal distribution on (a subset of) the entries in a matrix, this allows us to represent a distribution over rooted time trees. Here, we demonstrate tree distributions can be represented accurately this way for a number of published tree distributions. Though such a representation does not map to unique trees, restriction to a subspace, in particular one we call a "cube", makes the representation bijective at the cost of not being able to represent all possible trees. We introduce an algorithm "cubeVB" specifically for cubes and show through well calibrated simulation study that it is possible to recover parameters of interest like tree height and length. Although a cube cannot represent all of tree space, it is a great improvement over a single summary tree, and it opens up exciting new opportunities for scaling up Bayesian phylogenetic inference. We also demonstrate how to use a matrix representation of a tree distribution to get better summary trees than commonly used maximum clade credibility trees. An open source implementation of the cubeVB algorithm is available from https://github.com/rbouckaert/cubevb as the cubevb package for BEAST 2.
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Algoritmos , Teorema de Bayes , Filogenia , Análise por Conglomerados , Simulação por ComputadorRESUMO
BACKGROUND: We tackle the problem of estimating species TMRCAs (Time to Most Recent Common Ancestor), given a genome sequence from each species and a large known phylogenetic tree with a known structure (typically from one of the species). The number of transitions at each site from the first sequence to the other is assumed to be Poisson distributed, and only the parity of the number of transitions is observed. The detailed phylogenetic tree contains information about the transition rates in each site. We use this formulation to develop and analyze multiple estimators of the species' TMRCA. To test our methods, we use mtDNA substitution statistics from the well-established Phylotree as a baseline for data simulation such that the substitution rate per site mimics the real-world observed rates. RESULTS: We evaluate our methods using simulated data and compare them to the Bayesian optimizing software BEAST2, showing that our proposed estimators are accurate for a wide range of TMRCAs and significantly outperform BEAST2. We then apply the proposed estimators on Neanderthal, Denisovan, and Chimpanzee mtDNA genomes to better estimate their TMRCA with modern humans and find that their TMRCA is substantially later, compared to values cited recently in the literature. CONCLUSIONS: Our methods utilize the transition statistics from the entire known human mtDNA phylogenetic tree (Phylotree), eliminating the requirement to reconstruct a tree encompassing the specific sequences of interest. Moreover, they demonstrate notable improvement in both running speed and accuracy compared to BEAST2, particularly for earlier TMRCAs like the human-Chimpanzee split. Our results date the human - Neanderthal TMRCA to be [Formula: see text] years ago, considerably later than values cited in other recent studies.
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Hominidae , Homem de Neandertal , Animais , Humanos , Homem de Neandertal/genética , Filogenia , Pan troglodytes/genética , Teorema de Bayes , Hominidae/genética , DNA Mitocondrial/genéticaRESUMO
Infectious bronchitis virus (IBV) is prevalent in Pakistan causing enormous economic losses. To date no clear data are available on circulating genotypes and phylogeographic spread of the virus. Hence current study assessed these parameters for all available IBV Pakistani isolates, based on the 9 new sequences, with respect to other Asian and non-Asian countries. Results indicated that all Pakistani isolates belonged to genotype I (GI), with more than half of them (16/27) belonging to the GI-24 lineage, against which no vaccine is available. Three possible introduction events of the GI-13 IBV lineage into Pakistan, based on the estimated IBV population using isolates from this study, were observed possibly from Afghanistan, China, and/or Egypt. These events were further analyzed on the S1 amino acid level which showed unique alterations (S250H, T270K, and Q298S) in 1 isolate (IBV4, GI-13) when compared to GI-1 lineage. Both GI-1 and GI-13 Pakistani strains showed close homology with homologous vaccine strains that are used in Pakistan. For GI-24 strains, none of the used vaccines showed substantial homology, necessitating the need for further exploration of this lineage and vaccine design. In addition, our findings highlight the importance of genomic surveillance to support phylogeographical studies on IBV in genotyping and molecular epidemiology.
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Infecções por Coronavirus , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Vacinas , Animais , Filogeografia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/genética , Paquistão/epidemiologia , Genótipo , Filogenia , Galinhas , Doenças das Aves Domésticas/epidemiologiaRESUMO
A robust timetree for Mammalia was constructed using the time calibration function of BEAST v1.10.4 and MEGA 11. The analysis involved the application of times of the most recent common ancestors, including a total of 19 mammalian fossil calibration ages following Benton et al. (Palaeontologia Electronica, 2015, 1-106) for their minimum ages. Additionally, fossil calibration ages for Gorilla, Pan, and a geologic event calibration age for otters were incorporated. Using these calibration ages, I constructed a geologically calibrated tree that estimates the age of the Homo and Pan splitting to be 5.69 Ma. The tree carries several significant implications. First, after the initial rifting at 120 Ma, the Atlantic Ocean expanded by over 500 km around Chron 34 (84 Ma), and vicariant speciation between Afrotheria (Africa) and Xenarthra (South America) appears to have commenced around 70 Ma. Additionally, ordinal level differentiations began immediately following the K-Pg boundary (66.0 Ma), supporting previous hypothesis that mammalian radiation rapidly filled ecological niches left vacant by non-avian dinosaurs. I constructed a diagram depicting the relationship between base substitution rate and age using an additional function in BEAST v1.10.4. The diagram reveals an exponential increase in the base substitution rate approaching recent times. This increased base substitution rate during the Neogene period may have contributed to the expansion of biodiversity, including the extensive adaptive radiation that led to the evolution of Homo sapiens. One significant driving factor behind this radiation could be attributed to the emergence and proliferation of C4 grasses since 20 Ma. These grasses have played a role in increasing carbon fixation, reducing atmospheric CO2 concentration, inducing global cooling, and initiating Quaternary glacial-interglacial cycles, thereby causing significant climatic changes.
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Jingmen virus (JMV) associated with ticks and vertebrates have been found to be related to human disease. We obtained the genome of a Jingmen tick virus (JMTV) strain from Rhipicephalus microplus in Guizhou province and compared the genomes of seven JMV species associated with ticks and vertebrates to understand the evolutionary relationships. The topology of the phylogenetic tree of segment 1 and segment 3 is similar, and segment 2 and segment 4 formed two different topologies, with the main differences being between Alongshan virus (ALSV), Takachi virus, Yanggou tick virus and Pteropus lylei jingmen virus (PLJV), and the possibility of genetic reassortment among these viruses. Moreover, we detected recombination within JMTV and between PLJV and ALSV. The genetic reassortment and recombination that occurs during cross-species transmission of these JMV associated with ticks and vertebrates not only complicates their evolutionary relationships, but also raises the risk of these viruses to humans.
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Carrapatos , Vírus , Animais , Genômica , Filogenia , Vertebrados/genética , Vírus/genéticaRESUMO
Several hantaviruses result in zoonotic infections of significant public health concern, causing hemorrhagic fever with renal syndrome (HFRS) or hantavirus cardiopulmonary syndrome (HCPS) in the Old and New World, respectively. Given a 35% case fatality rate, disease-causing New World hantaviruses require a greater understanding of their biology, genetic diversity, and geographical distribution. Juquitiba hantaviruses have been identified in Oligoryzomys nigripes in Brazil, Paraguay, and Uruguay. Brazil has reported the most HCPS cases associated with this virus. We used a multiplexed, amplicon-based PCR strategy to screen and deep-sequence the virus harbored within lung tissues collected from Oligoryzomys species during rodent field collections in southern (Itapúa) and western (Boquerón) Paraguay. No Juquitiba-like hantaviruses were identified in Boquerón. Herein, we report the full-length S and M segments of the Juquitiba hantaviruses identified in Paraguay from O. nigripes. We also report the phylogenetic relationships of the Juquitiba hantaviruses in rodents collected from Itapúa with those previously collected in Canindeyú. We showed, using the TN93 nucleotide substitution model, the coalescent (constant-size) population tree model, and Bayesian inference implemented in the Bayesian evolutionary analysis by sampling trees (BEAST) framework, that the Juquitiba virus lineage in Itapúa is distinct from that in Canindeyú. Our spatiotemporal analysis showed significantly different time to the most recent ancestor (TMRA) estimates between the M and S segments, but a common geographic origin. Our estimates suggest the additional geographic diversity of the Juquitiba virus within the Interior Atlantic Forest and highlight the need for more extensive sampling across this biome.
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Vírus de RNA , Animais , Filogenia , Paraguai/epidemiologia , Teorema de Bayes , Sigmodontinae , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
H5Nx highly pathogenic avian influenza (HPAI) viruses of clade 2.3.4.4 have caused outbreaks in Europe among wild and domestic birds since 2016 and were introduced to North America via wild migratory birds in December 2021. We examined the spatiotemporal extent of HPAI viruses across continents and characterized ecological and environmental predictors of virus spread between geographic regions by constructing a Bayesian phylodynamic generalized linear model (phylodynamic-GLM). The findings demonstrate localized epidemics of H5Nx throughout Europe in the first several years of the epizootic, followed by a singular branching point where H5N1 viruses were introduced to North America, likely via stopover locations throughout the North Atlantic. Once in the United States (US), H5Nx viruses spread at a greater rate between US-based regions as compared to prior spread in Europe. We established that geographic proximity is a predictor of virus spread between regions, implying that intercontinental transport across the Atlantic Ocean is relatively rare. An increase in mean ambient temperature over time was predictive of reduced H5Nx virus spread, which may reflect the effect of climate change on declines in host species abundance, decreased persistence of the virus in the environment, or changes in migratory patterns due to ecological alterations. Our data provide new knowledge about the spread and directionality of H5Nx virus dispersal in Europe and the US during an actively evolving intercontinental outbreak, including predictors of virus movement between regions, which will contribute to surveillance and mitigation strategies as the outbreak unfolds, and in future instances of uncontained avian spread of HPAI viruses.
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Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A Subtipo H5N2 , Vírus da Influenza A , Influenza Aviária , Animais , Estados Unidos/epidemiologia , Influenza Aviária/epidemiologia , Teorema de Bayes , Surtos de Doenças/veterinária , Animais Selvagens , Aves , Europa (Continente)/epidemiologia , FilogeniaRESUMO
Bayesian phylogenetic inference requires a tree prior, which models the underlying diversification process that gives rise to the phylogeny. Existing birth-death diversification models include a wide range of features, for instance, lineage-specific variations in speciation and extinction (SSE) rates. While across-lineage variation in SSE rates is widespread in empirical datasets, few heterogeneous rate models have been implemented as tree priors for Bayesian phylogenetic inference. As a consequence, rate heterogeneity is typically ignored when reconstructing phylogenies, and rate heterogeneity is usually investigated on fixed trees. In this paper, we present a new BEAST2 package implementing the cladogenetic diversification rate shift (ClaDS) model as a tree prior. ClaDS is a birth-death diversification model designed to capture small progressive variations in birth and death rates along a phylogeny. Unlike previous implementations of ClaDS, which were designed to be used with fixed, user-chosen phylogenies, our package is implemented in the BEAST2 framework and thus allows full phylogenetic inference, where the phylogeny and model parameters are co-estimated from a molecular alignment. Our package provides all necessary components of the inference, including a new tree object and operators to propose moves to the Monte-Carlo Markov chain. It also includes a graphical interface through BEAUti. We validate our implementation of the package by comparing the produced distributions to simulated data and show an empirical example of the full inference, using a dataset of cetaceans.
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Especiação Genética , Filogenia , Teorema de Bayes , Método de Monte Carlo , Cadeias de MarkovRESUMO
Botryosphaeriales (Dothideomycetes, Ascomycota) occur in a wide range of habitats as endophytes, saprobes, and pathogens. The order Botryosphaeriales has not been subjected to evaluation since 2019 by Phillips and co-authors using phylogenetic and evolutionary analyses. Subsequently, many studies introduced novel taxa into the order and revised several families separately. In addition, no ancestral character studies have been conducted for this order. Therefore, in this study, we re-evaluated the character evolution and taxonomic placements of Botryosphaeriales species based on ancestral character evolution, divergence time estimation, and phylogenetic relationships, including all the novel taxa that have been introduced so far. Maximum likelihood, maximum parsimony, and Bayesian inference analyses were conducted on a combined LSU and ITS sequence alignment. Ancestral state reconstruction was carried out for conidial colour, septation, and nutritional mode. Divergence times estimates revealed that Botryosphaeriales originated around 109 Mya in the early epoch of the Cretaceous period. All six families in Botryosphaeriales evolved in the late epoch of the Cretaceous period (66-100 Mya), during which Angiosperms also appeared, rapidly diversified and became dominant on land. Families of Botryosphaeriales diversified during the Paleogene and Neogene periods in the Cenozoic era. The order comprises the families Aplosporellaceae, Botryosphaeriaceae, Melanopsaceae, Phyllostictaceae, Planistromellaceae and Saccharataceae. Furthermore, current study assessed two hypotheses; the first one being "All Botryosphaeriales species originated as endophytes and then switched into saprobes when their hosts died or into pathogens when their hosts were under stress"; the second hypothesis states that "There is a link between the conidial colour and nutritional mode in botryosphaerialean taxa". Ancestral state reconstruction and nutritional mode analyses revealed a pathogenic/saprobic nutritional mode as the ancestral character. However, we could not provide strong evidence for the first hypothesis mainly due to the significantly low number of studies reporting the endophytic botryosphaerialean taxa. Results also showed that hyaline and aseptate conidia were ancestral characters in Botryosphaeriales and supported the relationship between conidial pigmentation and the pathogenicity of Botryosphaeriales species.
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Phylogenetic estimation is, and has always been, a complex endeavor. Estimating a phylogenetic tree involves evaluating many possible solutions and possible evolutionary histories that could explain a set of observed data, typically by using a model of evolution. Values for all model parameters need to be evaluated as well. Modern statistical methods involve not just the estimation of a tree, but also solutions to more complex models involving fossil record information and other data sources. Markov chain Monte Carlo (MCMC) is a leading method for approximating the posterior distribution of parameters in a mathematical model. It is deployed in all Bayesian phylogenetic tree estimation software. While many researchers use MCMC in phylogenetic analyses, interpreting results and diagnosing problems with MCMC remain vexing issues to many biologists. In this manuscript, we will offer an overview of how MCMC is used in Bayesian phylogenetic inference, with a particular emphasis on complex hierarchical models, such as the fossilized birth-death (FBD) model. We will discuss strategies to diagnose common MCMC problems and troubleshoot difficult analyses, in particular convergence issues. We will show how the study design, the choice of models and priors, but also technical features of the inference tools themselves can all be adjusted to obtain the best results. Finally, we will also discuss the unique challenges created by the incorporation of fossil information in phylogenetic inference, and present tips to address them.
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Advances in genome sequencing techniques produced a significant growth of phylogenomic datasets. This massive amount of data represents a computational challenge for molecular dating with Bayesian approaches. Rapid molecular dating methods have been proposed over the last few decades to overcome these issues. However, a comparative evaluation of their relative performance on empirical data sets is lacking. We analyzed 23 empirical phylogenomic datasets to investigate the performance of two commonly employed fast dating methodologies: penalized likelihood (PL), implemented in treePL, and the relative rate framework (RRF), implemented in RelTime. They were compared to Bayesian analyses using the closest possible substitution models and calibration settings. We found that RRF was computationally faster and generally provided node age estimates statistically equivalent to Bayesian divergence times. PL time estimates consistently exhibited low levels of uncertainty. Overall, to approximate Bayesian approaches, RelTime is an efficient method with significantly lower computational demand, being more than 100 times faster than treePL. Thus, to alleviate the computational burden of Bayesian divergence time inference in the era of massive genomic data, molecular dating can be facilitated using the RRF, allowing evolutionary hypotheses to be tested more quickly and efficiently.
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Evolução Biológica , Genômica , Filogenia , Teorema de Bayes , ProbabilidadeRESUMO
Phylogeographic analyses aim to extract information about pathogen spread from genomic data, and visualising spatio-temporal reconstructions is a key aspect of this process. Here we present SPREAD 4, a feature-rich web-based application that visualises estimates of pathogen dispersal resulting from Bayesian phylogeographic inference using BEAST on a geographic map, offering zoom-and-filter functionality and smooth animation over time. SPREAD 4 takes as input phylogenies with both discrete and continuous location annotation and offers customised visualisation as well as generation of publication-ready figures. SPREAD 4 now features account-based storage and easy sharing of visualisations by means of unique web addresses. SPREAD 4 is intuitive to use and is available online at https://spreadviz.org, with an accompanying web page containing answers to frequently asked questions at https://beast.community/spread4.
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In this study 163 complete whole-genome sequences of the emerging pathogen grapevine red blotch virus (GRBV; genus Grablovirus, family Geminiviridae) were used to reconstruct phylogenies using Bayesian analyses on time-tipped (heterochronous) data. Using different combinations of priors, Bayes factors identified heterochronous datasets (3×200 million chains) generated from strict clock and exponential tree priors as being the most robust. Substitution rates of 3.2×10-5 subsitutions per site per year (95% HPD 4.3-2.1×10-5) across the whole of the GRBV genome were estimated, suggesting ancestral GRBV diverged from ancestral wild Vitis latent virus 1 around 9â000 years ago, well before the first documented arrival of Vitis vinifera in North America. Whole-genome analysis of GRBV isolates in a single infected field-grown grapevine across 12 years identified 12 single nucleotide polymorphisms none of which were fixed substitutions: an observation not discordant with the in silico estimate. The substitution rate estimated here is lower than those estimated for other geminiviruses and is the first for a woody-host-infecting geminivirus.
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Geminiviridae , Vitis , Teorema de Bayes , Geminiviridae/genética , Filogenia , Doenças das PlantasRESUMO
Flukes from the genus Paragonimus Braun, 1899 are medically important foodborne trematodes predominantly occurring throughout Asian countries. Providing molecular genetic characteristics based on ITS2 and partial 28 S rDNA of the paragonimids from the Russian Far East, Northeast, South, and Southeast Asian countries, we performed a partial reappraisal of Paragonimus westermani species complex. Members of this complex are genetically distinct worms with different divergence times and explosive expansion during Miocene-Pliocene epochs. We confirm the taxonomic status as valid species for P. ichunensis stat. n. (from the Russian Far East and Northern China), and P. filipinus (from the Philippines), which were previously considered subspecies of P. westermani, and reinstated the species name P. pulmonalis (from Japan). We suggest considering the worms from South Korea the Korean variety of P. ichunensis, because Korean specimens are sister and genetically closest to P. ichunensis from Northeast China and Primorsky region of Russia. Worms from South (India (type 2), Sri Lanka), Southeast (Malaysia, Vietnam, Thailand (types 1 and 2)) and East Asia (Taiwan) were left in the paragonimid systematics as Paragonimus sp. We propose to consider Indian worms of type 1 as true P. westermani, but in further revisions, due to the lack of holotype and unknown exact type locality, new type specimens (neotype) should be established.
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Many real-world decisions must be made on basis of experienced outcomes. However, there is little consensus about the mechanisms by which people make these decisions from experience (DfE). Across five experiments, we identified several factors influencing DfE. We also introduce a novel computational modeling framework, the memory for exemplars model (MEM-EX), which posits that decision makers rely on memory for previously experienced outcomes to make choices. Using MEM-EX, we demonstrate how cognitive mechanisms provide intuitive and parsimonious explanations for the effects of value-ignorance, salience, outcome order, and sample size. We also conduct a cross-validation analysis of several models within the MEM-EX framework. We compare these to three alternative models; two baseline models built on the principle of expected value maximization, and another employing a suite of choice methods previously shown to perform well in prediction tournaments. We find that MEM-EX consistently outperforms these competitors, demonstrating its value as a tool for making quantitative predictions without overfitting. We discuss the implications of these findings for our understanding of the interplay between attention, memory, and experience-based choice.