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Data from: Inflation of molecular clock rates and dates: molecular phylogenetics, biogeography, and diversification of a global cicada radiation from Australasia (Hemiptera: Cicadidae: Cicadettini)
Dated phylogenetic trees are important for studying mechanisms of diversification, and molecular clocks are important tools for studies of organisms lacking good fossil records. However, studies have begun to identify problems in molecular clock dates caused by uncertainty of the modeled molecular substitution process. Here we explore Bayesian relaxed-clock molecular dating while studying the biogeography of ca. 200 species from the global cicada tribe Cicadettini. Because the available fossils are few and uninformative, we calibrate our trees in part with a cytochrome oxidase I (COI) clock prior encompassing a range of literature estimates for arthropods. We show that tribe-level analyses calibrated solely with the COI clock recover extremely old dates that conflict with published estimates for two well-studied New Zealand subclades within Cicadettini. Additional subclade analyses suggest that COI relaxed-clock rates and maximum-likelihood branch lengths become inflated relative to EF-1α intron and exon rates and branch lengths as clade age increases. We present corrected estimates derived from (1) an extrapolated EF-1α exon clock derived from COI-calibrated analysis within the largest New Zealand subclade, (2) post-hoc scaling of the tribe-level chronogram using results from subclade analyses, and (3) exploitation of a geological calibration point associated with New Caledonia. We caution that considerable uncertainty is generated due to dependence of substitution estimates on both the taxon sample and the choice of model, including gamma category number and the choice of empirical versus estimated base frequencies. Our results suggest that diversification of the tribe Cicadettini commenced in the early- to mid-Cenozoic and continued with the development of open, arid habitats in Australia and worldwide. We find that Cicadettini is a rare example of a global terrestrial animal group with an Australasian origin, with all non-Australasian genera belonging to two distal clades. Within Australia, we show that Cicadettini is more widely distributed than any other cicada tribe, diverse in temperate, arid and monsoonal habitats, and nearly absent from rainforests. We comment on the taxonomic implications of our findings for thirteen cicada genera.
Data from: Revealing higher than expected diversity of Harpacticoida (Crustacea:Copepoda) in the North Sea using MALDI-TOF MS and molecular barcoding
The North Sea is one of the most extensively studied marine regions of the world. Hence, large amounts of molecular data for species identification are available in public repositories, and expectations to find numerous new species in this well-known region are rather low. However, molecular reference data for harpacticoid copepods from this area in particular but also for this group in general is scarce. By assessing COI barcodes and MALDI-TOF mass spectra for this group of small crustaceans, it was discovered that there is a huge unknown diversity in this area. In total, COI sequences for 548 specimens from 115 species of harpacticoid copepods are presented. Over 19% of these were new to science and ten MOTUs were found to be part of cryptic species complexes. MALDI-TOF mass spectra were assessed for 622 specimens from 75 species. Because results were in concordance with species delimitation by COI barcoding and also enabled recognition of possible cryptic species, the discriminative power of this technique for biodiversity assessments is highlighted. Findings imply, species diversity in this group may be largely underestimated and total species number can be expected to be much higher than previously assumed.
Data from: The timing of molecular and morphological changes underlying reproductive transitions in wild tomatoes (Solanum sect. Lycopersicon)
Molecular mechanisms underlying the transition from genetic self-incompatibility to self-compatibility are well documented, but the evolution of other reproductive trait changes that accompany shifts in reproductive strategy (mating system) remain comparatively poorly understood. A notable exception is the transition from exserted styles to styles with recessed positions relative to the anthers in wild tomatoes (Solanum Section Lycopersicon). This phenotypic change has been previously attributed to specific mutation in the promoter of a gene that influences style length (style2.1); however, whether this specific regulatory mutation arose concurrently with the transition from long- to short-styles, and whether it is causally responsible for this phenotypic transition, has been poorly investigated across this group. To address this gap, we assessed 74 accessions (populations) from 13 species for quantitative genetic variation in floral and reproductive traits as well as the presence/absence of deletions at two different locations (StyleD1, StyleD2) within the regulatory region upstream of style2.1. We confirmed that the putatively causal deletion variant (a 450bp deletion at StyleD1) arose within self-compatible lineages. However the variation and history of both StyleD1 and StyleD2 was more complex than previously inferred. In particular, although StyleD1 was statistically associated with differences in style length and stigma exsertion across all species, we found no evidence for this association within two species polymorphic for the StyleD1 mutation. We conclude that the previous association detected between phenotypic and molecular differences is most likely due to a phylogenetic association rather than a causal mechanistic relationship. Phenotypic variation in style length must therefore be due to other unexamined linked variants in the style2.1 regulatory region.
Data from: Phylogeny of salmonids (salmoniformes: Salmonidae) and its molecular dating: analysis of mtDNA data
Phylogenetic relationships among 41 species of salmonid fish and some aspects of their diversification-time history were studied using the GenBank and original mtDNA data. The position of the root of the Salmonidae phylogenetic tree was uncertain. Among the possible variants, the most reasonable seems to be that in which thymallins are grouped into the same clade as coregonins and the lineage of salmonins occupied a basal position relative to this clade. The genera of Salmoninae formed two distinct clades, i.e., (Brachymystax, Hucho) and (Salmo, Parahucho, (Salvelinus, (Parasalmo, Oncorhynchus)). Furthermore, the genera Parasalmo and Oncorhynchus were reciprocally monophyletic. The congruence of Salmonidae phylogenetic trees obtained using different types of phylogenetic markers is discussed. According to Bayesian dating, ancestral lineages of salmonids and their sister esocoids diverged about 106 million years ago. Sometime after, probably 100–70 million years ago, the salmonid-specific whole genome duplication took place. The divergence of salmonid lineages on the genus level occurred much later, within the time interval of 42–20 million years ago. The main wave of the diversification of salmonids at the species level occurred during the last 12 million years. The possible effect of genome duplication on the Salmonidae diversification pattern is discussed.
Data from: Morphological and molecular diagnostic species characters of Staurozoa (Cnidaria) collected on the coast of Helgoland (German Bight, North Sea)
Scientific knowledge and records on staurozoans are limited probably because of their inconspicuous life habit and the small number of specialists for this taxon. To increase the awareness for Staurozoa, we identified morphological and molecular features of the three staurozoan species Haliclystus tenuis Kishinouye, 1910, Haliclystus auricula Clark, 1863, and Craterolophus convolvulus (Johnston, 1835) collected on the coast of the island Helgoland to evaluate their suitability as diagnostic characters. Useful macromorphological diagnostic features were the patterns of white spots of nematocysts and internal arm structures, whereas tentacle and gonad follicle numbers showed high intraspecific variations. Morphometric measurements on photographs of living specimens provided reliable data for interspecific comparisons. Comprehensive nematocyst analyses revealed interspecific shape differences of isorhizas and three types of rhopaloids, indicating that the staurozoan cnidome is more diverse than previously assumed. However, the taxonomic value of nematocyst analyses in Staurozoa remains unclear because comprehensive data is still lacking for most species. Comparative molecular genetic sequence analyses of mitochondrial 16S and COI and nuclear 18S ribosomal DNA identified the three species and confirmed their morphological identification. In comparison to published data, our analyses indicate similarities between H. auricula and Haliclystus antarcticus Pfeffer, 1889. Proteomic fingerprinting by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) differentiated all three species, suggesting that this technique could provide an alternative rapid identification method for staurozoans.
Data from: Morphological, molecular, and ecological divergence in Pinus douglasiana and P. maximinoi
Pinus douglasiana and P. maximinoi (Pinus subsection Ponderosae) are closely-related New World pines with vague taxonomic boundaries where their natural ranges overlap in western Mexico. They are distinguished from each other by the width of their leaves and thickness of their cone scale apophyses. They are also sometimes confused with two other close relatives, Pinus pseudostrobus and P. yecorensis. We integrated morphological, molecular, and ecological data to clarify the taxonomic limits among these four species. Following previous studies, we evaluated 16 quantitative leaf and seed cone characters. Pinus douglasiana, P. maximinoi, and P. pseudostrobus formed non-discrete groups in multivariate space. The absence of leaf hypodermal intrusions, a persistent peduncle, and the shape of the seed cone are useful for differentiating P. pseudostrobus and P. yecorensis from P. douglasiana or P. maximinoi, and the latter two can usually be distinguished by needle width or cone scale apophysis thickness. Most individuals identified as P. douglasiana, and P. maximinoi shared haplotypes for a plastid ycf1 fragment that is relatively variable for the genus, while P. yecorensis has a closely related, exclusive haplotype. A distinct haplogroup included all individuals of P. pseudostrobus and the remaining individuals of P. douglasiana and P. maximinoi. Leaf width and cone scale thickness of P. douglasiana and P. maximinoi are correlated with elevation. According to potential distribution models, P. yecorensis is distributed in drier areas than P. douglasiana or P. maximinoi, while P. pseudostrobus occurs in more temperate areas, commonly at higher elevations. Pinus douglasiana and P. maximinoi can be considered as incipient species undergoing divergent evolution characterized by incomplete morphological, molecular, and ecological divergence.
Data from: Molecular cytogenetic and genomic insights to chromosomal evolution
This review summarizes aspects of the extensive literature on the patterns and processes underpinning chromosomal evolution in vertebrates and especially placental mammals. It highlights the growing synergy between molecular cytogenetics and comparative genomics, particularly with respect to fully or partially sequenced genomes, and provides novel insights into changes in chromosome number and structure across deep division of the vertebrate tree of life. The examination of basal numbers in the deeper branches of the vertebrate tree suggest a haploid (n) chromosome number of 10–13 in an ancestral vertebrate, with modest increases in tetrapods and amniotes most probably by chromosomal fissioning. Information drawn largely from cross-species chromosome painting in the data-dense Placentalia permits the confident reconstruction of an ancestral karyotype comprising n=23 chromosomes that is similarly retained in Boreoeutheria. Using in silico genome-wide scans that include the newly released frog genome we show that of the nine ancient syntenies detected in conserved karyotypes of extant placentals (thought likely to reflect the structure of ancestral chromosomes), the human syntenic segmental associations 3p/21, 4pq/8p, 7a/16p, 14/15, 12qt/22q and 12pq/22qt predate the divergence of tetrapods. These findings underscore the enhanced quality of ancestral reconstructions based on the integrative molecular cytogenetic and comparative genomic approaches that collectively highlight a pattern of conserved syntenic associations that extends back ~360 million years ago.
Data from: Molecular phylogenetics and the evolution of fruit and leaf morphology of Dichaea (Orchidaceae: Zygopetalinae)
BACKGROUND AND AIMS: The orchid genus Dichaea, with over 100 species found throughout the neotropics, is easily recognized by distichous leaves on long stems without pseudobulbs and flowers with infrastigmatic ligules. The genus has previously been divided into four sections based primarily on presence of ovary bristles and a foliar abscission layer. The aim of this work is to use DNA sequence data to estimate phylogenetic relationships within Dichaea and map the distribution of major morphological characters that have been used to delimit subgenera/sections. METHODS: Sequence data for the nuclear ribosomal internal transcribed spacers and plastid matK, trnL intron, trnL-F spacer and ycf1 for 67 ingroup and seven outgroup operational taxonomic units were used to estimate phylogenetic relationships within Dichaea. Taxa from each of the four sections were sampled, with the greatest representation from section Dichaea, the most diverse and taxonomically puzzling group. KEY RESULTS: Molecular data and morphology support monophyly of Dichaea. Results indicate that section Dichaeopsis is polyphyletic and based on symplesiomorphies, including deciduous leaves and smooth ovaries that are widespread in Zygopetalinae. There are at least three well-supported clades within section Dichaeopsis. Section Pseudodichaea is monophyletic and defined by setose ovaries and leaves with an abscission layer. Sections Dichaea and Dichaeastrum are monophyletic and defined by pendent habit and persistent leaves. Section Dichaeastrum, distinguished from section Dichaea primarily by a glabrous ovary, is potentially polyphyletic. CONCLUSIONS: The leaf abscission layer was lost once, occurring only in the derived sections Dichaea and Dichaeastrum. The setose fruit is a more homoplasious character with several losses and gains within the genus. We propose an informal division of the genus based upon five well-supported clades.
Data from: Molecular insights into the lichen genus Alectoria (Parmeliaceae) in North America
Alectoria is a genus of fruticose lichen characterised by the presence of usnic acid and conspicuous raised pseudocyphellae. This genus is particularly diverse and abundant in montane, boreal, and Arctic regions of North America. Because intermediate forms have been reported for several species of Alectoria on the continent, it has been suggested that these species were initially delimited based on the extremes of morphological gradients. Here, we use the results of molecular phylogenetic analyses of two nuclear genes, ITS and Mcm7, with 48 representatives of 9 taxa to examine the delineation of 5 taxa that have been previously shown to be related to, or confused with, A. sarmentosa: A. fallacina, A. imshaugii, A. sarmentosa var. sorediosa, A. sarmentosa subsp. vexillifera, and A. vancouverensis. Alectoria fallacina was found to be well-supported and distantly related to A. sarmentosa. Conversely, the other four taxa were recovered as a single monophyletic group with little internal structure, which did not support the presently defined morphological species. A provisional taxonomic treatment is proposed pending more detailed study at the population level. Alectoria sarmentosa var. sorediosa is recognized at the species level, which necessitates the new combination: A. sorediosa. An updated key to the North American species of Alectoria is also provided.
Data from: High-throughput molecular identification of fish eggs using multiplex suspension bead arrays
The location and abundance of fish eggs provide information concerning the timing and location of spawning activities and can provide fishery-independent estimates of spawning biomass. However, the full value of egg and larval surveys is severely restricted because many species' eggs and larvae are morphologically similar, making species-level identification difficult. Recent efforts have shown that nearly all species of fish may be identified by mitochondrial DNA (mtDNA) sequences (e.g., via "DNA barcoding"). By taking advantage of a DNA barcode database, we have developed oligonucleotide probes for 23 marine fish species that produce pelagic eggs commonly found in California waters. Probes were coupled to fluorescent microspheres to create a suspension bead array. Biotin-labeled primers were used to amplify the mitochondrial cytochrome oxidase subunit I (COI) and 16S ribosomal rRNA genes from individual fish eggs. The amplicons were then hybridized to the bead array and after addition of a reporter fluorophore, samples were analyzed by flow cytometry with Luminex 100 instrumentation. Probes specifically targeted eggs that are abundant and/or from morphologically indistinguishable species pairs. Results showed the 33 different probes designed for this study accurately identified all samples when PCR was successful. Suspension bead arrays have a number of benefits over other methods of molecular identification; these arrays permit high multiplexing, simple addition of new probes, high throughput, and lower cost than DNA sequencing. The increasing availability of DNA barcode data for numerous fish faunas worldwide suggests bead arrays could be developed and widely used for fish egg, larval and tissue identifications.
Data from: Molecular characterization of copepod photoreception
Copepod crustaceans are an abundant and ecologically significant group whose basic biology is guided by numerous visually guided behaviors. These behaviors are driven by copepod eyes, including naupliar eyes and Gicklhorn's organs, which vary widely in structure and function among species. Yet little is known about the molecular aspects of copepod vision. In this study we present a general overview of the molecular aspects of copepod vision by identifying phototransduction genes from newly generated and publicly available RNA-sequencing data and assemblies from 12 taxonomically diverse copepod species. We identify a set of 10 expressed transcripts that serve as a set of target genes for future studies of copepod phototransduction. Our more detailed evolutionary analyses of the opsin gene responsible for forming visual pigments found that all of the copepod species investigated express two main groups of opsins: middle-wavelength-sensitive (MWS) opsins and pteropsins. Additionally, there is evidence from a few species (e.g., Calanus finmarchicus, Eurytemora affinis, Paracyclopina nana, and Lernaea cyprinacea) for the expression of two additional groups of opsins—the peropsins and rhodopsin 7 (Rh7) opsins—at low levels or distinct developmental stages. An ontogenetic analysis of opsin expression in Calanus finmarchicus found the expression of a single dominant MWS opsin, as well as evidence for differences in expression across development in some MWS, pteropsin, and Rh7 opsins, with expression peaking in early naupliar through early copepodite stages.
Data from: Early mechanistic events induced by low molecular weight polycyclic aromatic hydrocarbons in mouse lung epithelial cells: a role for eicosanoid signaling
Low molecular weight polycyclic aromatic hydrocarbons (LMW PAHs; <206.3 g/mol) are under regulated environmental contaminants (e.g., secondhand smoke) that lead to gap junction dysregulation, p38 MAPK activation, and increased mRNA production of inflammatory mediators, such as cytokines and cyclooxygenase (COX2), in lung epithelial cells. However, the early mechanisms involving lipid signaling through the arachidonic acid pathway and subsequent eicosanoid production leading to these downstream events are not known. Common human exposures are to mixtures of LMW PAH's, thus C10 cells (a mouse lung epithelial cell line) were exposed to a representative binary PAH mixture, 1-methylanthracene (1-MeA) and fluoranthene (Flthn), for 30 min – 24 h with and without p38 and cytosolic phospholipase A2 (cPLA2) inhibitors. cPLA2 inhibition reversed PAH-induced phospho-p38 MAPK activation and gap junction dysregulation at 30 min. A significant biphasic increase of cPLA2 protein was observed at 30 min, 2, & 4 h, as well as COX2 protein at 2 & 8 h. Untargeted metabolomics demonstrated a similar trend with significantly changing metabolites at 30 min & 4 h of exposure relative to 1 h; a "cPLA2-like" subset of metabolites within the biphasic response were predominately phospholipids. argeted metabolomics showed several eicosanoids (e.g., prostaglandin D2 (PGD2), PGE2α) were significantly increased at 4, 8, and 12 h following exposure to the binary PAH mixture and this effect was p38-dependent. Lastly, PAH metabolism was not observed until after 8 h. These results indicate an early lipid signaling mechanism of PAH toxicity in lung epithelial cells due to parent PAH compounds.
Data from: Molecular phenotyping of maternally mediated parallel adaptive divergence within Rana arvalis and Rana temporaria
When similar selection acts on the same traits in multiple species or populations, parallel evolution can result in similar phenotypic changes, yet the underlying molecular architecture of parallel phenotypic divergence can be variable. Maternal effects can influence evolution at ecological timescales and facilitate local adaptation, but their contribution to parallel adaptive divergence is unclear. In this study, we (i) tested for variation in embryonic acid tolerance in a common garden experiment and (ii) used molecular phenotyping of egg coats to investigate the molecular basis of maternally mediated parallel adaptive divergence in two amphibian species (Rana arvalis and Rana temporaria). Our results on three R. arvalis and two R. temporaria populations show that adaptive divergence in embryonic acid tolerance is mediated via maternally derived egg coats in both species. We find extensive polymorphism in egg jelly coat glycoproteins within both species and that acid-tolerant clutches have more negatively charged egg jelly – indicating that the glycosylation status of the jelly coat proteins is under divergent selection in acidified environments, likely due to its impact on jelly water balance. Overall, these data provide evidence for parallel mechanisms of adaptive divergence in two species. Our study highlights the importance of studying intraspecific molecular variation in egg coats and, specifically, their glycoproteins, to increase understanding of underlying forces maintaining variation in jelly coats.
Data from: Peperomia (Piperaceae) from Trindade Island: a new species based on morphological and molecular data
Peperomia is one of the largest genera of basal angiosperms, with about 1,600 species, distributed pantropically. The Brazilian oceanic island of Trindade is located about 1,200km off the Brazilian coast; its maximum altitude is 620ma.s.l. and its area is 9.28km2. Among the 113 species of vascular plants reported for Trindade Island there are two species of Peperomia: Peperomia beckeri, an endemic species known only from the type specimen; and Peperomia glabella.We re-evaluated specimens attributed to P. glabella from Trindade Island and compared them to specimens from the continent. The comparison included morphological analyses of the vegetative and reproductive organs, and a molecular phylogenetic study using the molecular markers trnK/matK and ITS. The trnK/matK marker showed significant differences between Peperomia from the mainland and Trindade. Together, these studies showed that the Peperomia occurring on Trindade is a species that differs both from those previously recorded on Trindade Island and from those on the continent, leading us to describe a new species. Peperomia segregata is endemic to Trindade, and would likely be considered critically endangered according to the IUCN criteria.
Data from: Plant – herbivorous beetle networks: molecular characterization of trophic ecology within a threatened steppic environment
DNA barcoding facilitates many evolutionary and ecological studies, including the examination of the dietary diversity of herbivores. In this study, we present a survey of ecological associations between herbivorous beetles and host plants from seriously threatened European steppic grasslands. We determined host plants for the majority (65%) of steppic leaf beetles (55 species) and weevils (59) known from central Europe using two barcodes (trnL and rbcL) and two sequencing strategies (Sanger for mono/oligophagous species and Illumina for polyphagous taxa). To better understand the ecological associations between steppic beetles and their host plants, we tested the hypothesis that leaf beetles and weevils differ in food selection as a result of their phylogenetic relations (within genera and between families) and interactions with host plants. We found 224 links between the beetles and the plants. Beetles belonging to seven genera feed on the same or related plants. Their preferences were probably inherited from common ancestors and/or resulted from the host plant's chemistry. Beetles from four genera feed on different plants, possibly reducing intrageneric competition and possibly due to an adaptation to different plant chemical defences. We found significant correlations between the numbers of leaf beetle and weevil species feeding on particular plants for polyphagous taxa, but not for nonpolyphagous beetles. Finally, we found that the previous identifications of host plants based on direct observations are generally concordant with host plant barcoding from insect gut. Our results expand basic knowledge about the trophic relations of steppic beetles and plants and are immediately useful for conservation purposes.
Data from: A reevaluation of the Andean Genus Petroravenia (Brassicaceae: Thelypodieae) based on morphological and molecular data
Abstract Petroravenia was until recently considered as a genus of three species (P. eseptata, P. friesii, and P. werdermannii) distributed along the Central Andes of Argentina, Bolivia, Chile, and Peru. This genus was included in the tribe Thelypodieae and was morphologically characterized by being tiny rhizomatous perennial herbs with rosulate leaves, dendritic trichomes, capsular silicles, and incumbent cotyledons. However, the phylogeny of Petroravenia, and its tribal placement, was never analyzed using molecular data. The lack of such studies, as well as the paucity of herbarium collections, suggesting that Petroravenia species are vulnerable and/or endangered, prompted us to address the molecular phylogeny of this genus. For this purpose, we generated comprehensive molecular phylogenies using nuclear (ITS) and plastid (trnL-F and trnH-psbA) data, and conducted morphological comparisons between these species and their closest related taxa. Results from the phylogenetic analyses showed that Petroravenia represents a polyphyletic group, with P. eseptata included in tribe Halimolobeae, and P. friesii and P. werdermannii placed within tribe Eudemeae and related to the genus Alshehbazia. Based on the results obtained from morphological and molecular data, we decided herein to retain the original circumscription of Petroravenia as monospecific within the tribe Halimolobeae and to transfer P. friesii and P. werdermannii to the genus Alshehbazia within the tribe Eudemeae. Systematic implications of these results are also discussed.
Data from: Molecular evolution of anthocyanin pigmentation genes following losses of flower color
Background: Phenotypic transitions, such as trait gain or loss, are predicted to carry evolutionary consequences for the genes that control their development. For example, trait losses can result in molecular decay of the pathways underlying the trait. Focusing on the Iochrominae clade (Solanaceae), we examine how repeated losses of floral anthocyanin pigmentation associated with flower color transitions have affected the molecular evolution of three anthocyanin pathway genes (Chi, F3h, and Dfr). Results: We recovered intact coding regions for the three genes in all of the lineages that have lost floral pigmentation, suggesting that molecular decay is not associated with these flower color transitions. However, two of the three genes (Chi, F3h) show significantly elevated dN/dS ratios in lineages without floral pigmentation. Maximum likelihood analyses suggest that this increase is due to relaxed constraint on anthocyanin genes in the unpigmented lineages as opposed to positive selection. Despite the increase, the values for dN/dS in both pigmented and unpigmented lineages were consistent overall with purifying selection acting on these loci. Conclusions: The broad conservation of anthocyanin pathway genes across lineages with and without floral anthocyanins is consistent with the growing consensus that losses of pigmentation are largely achieved by changes in gene expression as opposed to structural mutations. Moreover, this conservation maintains the potential for regain of flower color, and indicates that evolutionary losses of floral pigmentation may be readily reversible.
Data from: Molecular operational taxonomic units reveal restricted geographic ranges and regional endemism in the Indo‐Pacific octocoral family Xeniidae
Aim: To quantify taxon diversity, biogeographic distributions and patterns of community assembly in xeniid octocorals using molecular operational taxonomic units (MOTUs). Location Red Sea, Indian and western Pacific Oceans. Taxon Xeniidae, a family of reef-dwelling octocorals (Anthozoa, Octocorallia). Methods Xeniids collected at 13 locations were sequenced at three barcode loci, and assigned to molecular operational taxonomic units (MOTUs) defined by minimum genetic distance thresholds. Taxon richness (no. of MOTUs) and endemicity (percent of MOTUs found at a single location) were quantified. Patterns of β-diversity (species turnover) and phylogenetic β-diversity (lineage turnover) among geographical regions were visualized using hierarchical clustering, NMDS plots, and distance-decay relationships. Community assembly was investigated by comparing the mean pairwise distance (MPD) and mean nearest taxon distance (MNTD) separating species in each assemblage to values generated for null communities. Results A genetic distance threshold of 0.3% discriminated 67 MOTUs, with taxon richness ranging from 2-18 MOTUs per site. Out of the 67 MOTUs, 48 (72%) were found at only a single location, and only two spanned both the western Indian and Pacific Oceans. Species turnover among sites was high, but phylogenetic β-diversity was lower than β-diversity and differed significantly from null models of community assembly at only two sites. β-diversity and phylogenetic β-diversity both increased significantly with geographic distance, and sites clustered into three distinct biogeographic regions (Red Sea and western Indian Ocean; Western Australia; western Pacific and Great Barrier Reef, Australia). All five major clades of xeniids were represented in each region. Main Conclusions A genetic approach to biodiversity estimation suggests that most xeniid taxa are regional endemics whose geographic distribution is likely governed by dispersal limitation. This conclusion contrasts with published records of certain morphospecies occurrences, which imply that they have broad geographic ranges. So far, the distribution of xeniid biodiversity mirrors that of scleractinian corals, with species richness highest in the Coral Triangle, but endemicity peaking in peripheral areas.
Data from: Multi-serotype pneumococcal nasopharyngeal carriage prevalence in vaccine naïve Nepalese children, assessed using molecular serotyping.
Invasive pneumococcal disease is one of the major causes of death in young children in resource poor countries. Nasopharyngeal carriage studies provide insight into the local prevalence of circulating pneumococcal serotypes. There are very few data on the concurrent carriage of multiple pneumococcal serotypes. This study aimed to identify the prevalence and serotype distribution of pneumococci carried in the nasopharynx of young healthy Nepalese children prior to the introduction of a pneumococcal conjugate vaccine using a microarray-based molecular serotyping method capable of detecting multi-serotype carriage. We conducted a cross-sectional study of healthy children aged 6 weeks to 24 months from the Kathmandu Valley, Nepal between May and October 2012. Nasopharyngeal swabs were frozen and subsequently plated on selective culture media. DNA extracts of plate sweeps of pneumococcal colonies from these cultures were analysed using a molecular serotyping microarray capable of detecting relative abundance of multiple pneumococcal serotypes. 600 children were enrolled into the study: 199 aged 6 weeks to <6 months, 202 aged 6 months to < 12 months, and 199 aged 12 month to 24 months. Typeable pneumococci were identified in 297/600 (49·5%) of samples with more than one serotype being found in 67/297 (20·2%) of these samples. The serotypes covered by the thirteen-valent pneumococcal conjugate vaccine were identified in 44·4% of samples containing typeable pneumococci. Application of a molecular serotyping approach to identification of multiple pneumococcal carriage demonstrates a substantial prevalence of co-colonisation. Continued surveillance utilising this approach following the introduction of routine use of pneumococcal conjugate vaccinates in infants will provide a more accurate understanding of vaccine efficacy against carriage and a better understanding of the dynamics of subsequent serotype and genotype replacement.
Data from: Molecular phylogenetics of Gobioidei and phylogenetic placement of European gobies
Gobioidei is one of the largest suborders of teleost fishes, with nearly 2000 extant species currently recognized. They have a worldwide distribution and show a spectacular variety in morphology, ecology, and behavior. Despite their importance, phylogenetic relationships among many groups of gobioids (including some of the major lineages) still remain poorly understood. In this study, we analyze sequence data of five molecular markers (two mitochondrial and three nuclear) averaging 6000 bp for 222 species of gobioids. Our study is the first to include both multiple nuclear and mitochondrial genes to reconstruct a comprehensive multilocus phylogeny of gobioids encompassing most major lineages representing the overall diversity of one of the most speciose vertebrate lineages. Two separate datasets are produced and used to specifically address the phylogenetic placement of Rhyacichthyidae and Odontobutidae, and the phylogenetic relationships among the lineages of Gobioidei. Our results strongly support that the initial split in the gobioid tree separated a clade containing Rhyacichthyidae + Odontobutidae as the sister group of all other lineages. The family Eleotrididae branches off the gobioid tree after the Rhyacichthyidae + Odontobutidae clade, followed by the Butidae as sister to the Gobiidae. Additionally, several major monophyletic groups are confidently identified within the two major Gobiidae subclades, the gobiine-like gobiids and the gobionelline-like gobiids. Robustness of the phylogenetic trees inferred here is significantly higher than that of previous studies, hence our results provide the most compelling molecular phylogenetic hypothesis of Gobioidei thus far. For the first time, we provide a comprehensive sampling of European gobies that traditionally have been divided into "transverse" and "sand gobies". We show that the European gobies cluster in three distinct lineages, the Pomatoschistus-, Aphia-, and Gobius-lineages. The former resolved within the gobionelline-like gobiids and the latter two within the gobiine-like gobiids. These findings have significant implications for our understanding of the phylogeographic origin of European gobies in the light of the closure of the Paratethys. A rogue taxon analysis identified Kraemeria as an unstable taxon decreasing support at the base of the gobiine-like gobiids. Removal of this rogue taxon significantly increased phylogenetic resolution in that part of the tree and revealed additional insights into early bursts of cladogenesis of the gobiine-like gobiids.
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Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.