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3,101 results for “Historical”
Evaluating multiple historical climate products in ecological models under current and projected temperatures
<p>Gridded historical climate products (GHCPs) are employed with increasing frequency when modeling ecological phenomena across large scales and predicting ecological responses to projected climate changes. Concurrently, there is an increasing acknowledgement of the need to account for uncertainty when employing climate projections from ensembles of global circulation models (GCMs) and emissions scenarios. Despite the growing usage and documented differences among GHCPs, uncertainty characterization has primarily focused on the roles of GCM and emissions scenario choice, while the consequences of using a single GHCP to make predictions over space and time has received relatively less attention. Here we employ average July temperature data from observations and seven GHCPs to model plant canopy cover and tree basal area across central Alaska, U.S.A. We first compare fit and support of models employing raw observed or GHCP temperature values versus those with an elevation adjustment, finding (1) greater support for, and better fit using elevation-adjusted versus raw temperature models and (2) overall similar fits of elevation-adjusted models employing temperature from observations or GHCPs. Focusing on basal area, we next compare predictions generated by elevation-adjusted models employing GHCP data under current conditions and a warming scenario of current temperatures plus 2 °C, finding good agreement among GHCPs though with between-GHCP differences and variation primarily at middle elevations (~ 1,000 m). These differences were amplified under the warming scenario. Finally, using pooled indices of prediction variation and difference across GHCP models, we identify characteristics of areas most likely to exhibit prediction uncertainty under current and warming conditions. Despite (1) overall good performance of GHCP data relative to observations in models and (2) positive correlation among model predictions, variation in predictions across models—particularly in mid-elevation areas where the position of treeline may be changing—suggests researchers should exercise caution if selecting a single GHCP for use in models. We recommend the use of multiple GHCPs to provide additional uncertainty information beyond standard estimated prediction intervals, particularly when model predictions are employed in conservation planning.</p>
A molecular phylogeny of historical and contemporary specimens of an under-studied micro-invertebrate group
<p>Resolution of relationships at lower taxonomic levels is crucial for answering many evolutionary questions, and as such, sufficiently varied species representation is vital. This latter goal is not always achievable with relatively fresh samples. To alleviate the difficulties in procuring rarer taxa, we have seen increasing utilization of historical specimens in building molecular phylogenies using high throughput sequencing. This effort, however, has mainly focused on large-bodied or well-studied groups, with small-bodied and under-studied taxa under-prioritized. Here, we utilize both historical and contemporary specimens, to increase the resolution of phylogenetic relationships among a group of under-studied and small-bodied metazoans, namely, cheilostome bryozoans. In this study, we pioneer sequencing of air-dried cheilostomes, utilizing a recent library preparation method for low DNA input. We evaluate a <i>de novo</i> mitogenome assembly and two iterative methods, using the sequenced target specimen as a reference for mapping, for our sequences. In doing so, we present mitochondrial and ribosomal RNA sequences of 43 cheilostomes representing 37 species, including 14 from historical samples ranging from 50 to 149 years old. The inferred phylogenetic relationships of these samples, analyzed together with publicly available sequence data, are shown in a statistically well-supported 65 taxa and 17 genes cheilostome tree, which is also the most broadly sampled and largest to date. The robust phylogenetic placement of historical samples whose contemporary conspecifics and or congenerics have been sequenced verify the appropriateness of our workflow and give confidence in the phylogenetic placement of those historical samples for which there are no close relatives sequenced. The success of our workflow is highlighted by the circularization of a total of 27 mitogenomes, seven from historical cheilostome samples. Our study highlights the potential of utilizing DNA from micro-invertebrate specimens stored in natural history collections for resolving phylogenetic relationships among species.</p>
Data from: Phylotranscriptomics resolves interspecific relationships and indicates multiple historical out-of-North America dispersals through the Bering Land Bridge for the genus Picea (Pinaceae)
A robust phylogeny is prerequisite to understand the evolution and biogeography of organisms. However, ancient and recent evolutionary radiations occurred in many plant lineages, which pose great challenges for phylogenetic analysis, especially for conifers characterized by large effective population sizes and long generation times. Picea is an important component of the dark coniferous forests in the Northern Hemisphere. Previous studies improved our understanding of its evolutionary history, but its interspecific relationships and biogeographic history remain largely unresolved. In the present study, we reconstructed a well-resolved phylogeny of Picea by comparative transcriptomic analysis based on a complete species sampling. The phylogenetic analysis, together with molecular dating and ancestral area reconstruction, further supports the North American origin hypothesis for Picea, and indicates that this genus experienced multiple out-of-North America dispersals by the Bering Land Bridge. We also found that spruces in the Japanese Archipelago have multiple origins, and P. morrisonicola from the Taiwan Island has a close relationship with species from the Qinghai-Tibetan Plateau and adjacent regions. Our study provides the first complete phylogeny of Picea at the genomic level, which is important for future studies of this genus.
Data from: Historical contingency, niche conservatism and the tendency for some taxa to be more diverse towards the poles
Aim We test the ability of the biotic exchange across the Bering land-bridge coupled to niche conservatism to explain current day mammalian diversity gradients. Location the Holarctic Taxon mammals Methods We compared the diversity within clades that participated in the exchange (colonizers), whose ancestors withstood the Beringian cold temperatures, with that within clades that did not participate (sedentaries). We contrasted biogeographical patterns, tested the ability of environmental models to predict species richness of colonizers and sedentaries across continents and, compared richness-climate relationships between colonizers and sedentaries controlling for phylogenetic effects. Results We find that assemblages of colonizers are more diverse towards higher latitudes, opposing the traditional latitudinal diversity gradient which is followed by sedentaries. Despite the long passage of time since this major dispersal event, we find that the geographic distribution of colonizers is more strongly correlated to the distributions of other colonizers inhabiting a different continent than to the distribution of sedentary species. Main conclusions Our results highlight the importance of historical migrations and dispersal in configuring present-day diversity gradients. We also suggest that colonizers may be particularly vulnerable to future climate change because of the predicted disproportionate decrease in climate space in the extra-tropical realm where they are currently most diverse.
EPARCHOS - Historical Greek handwritten document dataset
<p>The dataset originates from a Greek handwritten codex that dates from around 1500-1530. This is the subset of the codex British Museum Addit. 6791, written by two hands, one by Antonius Eparchos and the other by Camillos Zanettus (ff. 104r-174v) and delivers texts by Hierocles (In Aureum carmen), Matthaeus Blastares (Collectio alphabetica) and, notably, texts by Michael Psellos (De omnifaria doctrina). The writing delivers the most important abbreviations, logograms and conjunctions, which are cited in virtually every Greek minuscule handwritten codex from the years of the manuscript transliteration and the prevalence of the minuscule script (9th century) to the post-Byzantine years. This dataset consists of 120 scanned handwritten text pages, containing 9285 lines of text, 18809 words (6787 unique words). For each page, a PageXML is provided containing the following groundtruth:</p> <ol> <li>Text region polygon coordinates</li> <li>Text line polygon coordinates with the corresponding transcription text</li> <li>Word polygon coordinated with the corresponding transcription text</li> </ol>
Hidden in the DNA: insights on how multiple historical processes and natural history traits shaped patterns of cryptic diversity in an Amazon leaf-litter lizard Loxopholis osvaldoi (Squamata: Gymnophthalmidae).
Aim: To investigate cryptic diversity and diversification timing in the putatively low-dispersal Amazonian leaf-litter lizard Loxopholis osvaldoi, and to ask how geography (rivers, isolation by distance, IBD), ecological drivers (isolation by environment, IBE) and historical factors (climatic refugia) explain intraspecific genetic variation. Location: Central Amazonia, Brazil. Taxon: Squamata; Gymnophthalmidae; Loxopholis osvaldoi. Methods: We sequenced two mitochondrial and two nuclear markers in 157 individuals. Phylogeographic structure and the occurrence of independent evolving lineages where explored through phylogenetic and coalescent analyses. A species tree and divergence dates of lineages were inferred with BEAST, employing multiple DNA substitution rates. The potential genetic impacts of geographic distance among localities, the environment, and the position of localities in relation to main rivers were tested by Redundancy Analysis (RDA). Results: We detected 11 independently evolving and largely divergent intraspecific lineages. Lineage distribution patterns are complex and do not match any conspicuous barrier to gene flow, except for the Amazon River. Most lineages appear to have originated in the lower Miocene and Pliocene, in disagreement with the Pleistocene refuge hypothesis. IBD, IBE, and rivers appear to have acted in concert establishing and maintaining genetic structure. However, when controlling for other explanatory variables, IBD explains significantly more variation than rivers, IBE, or historical factors. Main conclusions: Our results strongly suggest that L. osvaldoi is a species complex. Future taxonomic work should use an integrative approach to explore whether morphological variation is present and congruent with the genetic data. While the use of a sensitive dating analysis allowed us to better describe the diversification history of L. osvaldoi, the lack of a spatial model of Neogene river dynamics prevents the test of specific, more informative river barrier hypotheses. The data suggest that non-linear correlation analyses (e.g. RDA) should be preferred to detect factors that affect phylogeographic patterns in the Amazon, instead of linear multiple regressions (e.g. Mantel tests). Given the high level of cryptic diversity detected within this and other Amazonian species, we caution against hypothesis tests based solely on the distribution of nominal taxa, which can provide a rather incomplete view of the processes behind Amazonian diversity.
Regionally divergent drivers of historical diversification in the late Quaternary in a widely distributed generalist species, the common pheasant Phasianus colchicus
<p>Aim: Pleistocene climate and associated environmental changes have influenced phylogeographic patterns of many species. These not only depend on a species' life history but also vary regionally. Consequently, populations of widespread species that occur in several biomes might display different evolutionary trajectories. We aimed to identify regional drivers of diversification in the common pheasant, a widely distributed ecological generalist. <br> <br> Study location Asia<br> <br> Taxon common pheasant Phasianus colchicus<br> <br> Methods Using a comprehensive geographic sampling of 204 individuals from the species' entire range genotyped at seven nuclear and two mitochondrial loci, we reconstructed spatio-temporal diversification and demographic history of the common pheasant. We applied Bayesian phylogenetic inference to describe phylogeographic structure, generated a species tree, and inferred demographic history within and migration between lineages. Moreover, to establish a taxonomic framework, we conducted a species delimitation analysis.<br> Results The common pheasant diversified during the late Pleistocene into eight distinct lineages. It originated at the edge of the Qinghai-Tibetan plateau and spread to East and Central Asia. Only the widely distributed lowland lineage of East Asia displayed recent range expansion. Greater phylogeographic structure was identified elsewhere, with lineages showing no sign of recent demographic changes. One lineage in south-central China is the result of long-term isolation within a climatically stable but topographically complex region. In lineages from arid Central Asia and China, range expansions were impeded by repeated population fragmentation during dry glacial periods and by recent aridification. <br> <br> Main conclusions <br> Spatio-temporal phylogeographic frameworks of widespread taxa such as the common pheasant provide valuable opportunities to identify divergent drivers of regional diversification. Our results suggest that diversification and population histories in the eight distinct evolutionary lineages were shaped by regionally variable effects of past climate and associated environmental changes. The evolutionary history of the common pheasant is best reflected by its being split into three species.</p>
Twenty-two Historical Encyclopedias (Original XML Encoding)
<p>This dataset accompanies the publication of "Twenty-two Historical Encyclopedias Encoded in TEI: a New Resource for the Digital Humanities".</p> <p>Licensed as CC-BY.</p>
Data from: Historical climatic instability predicts the inverse latitudinal pattern in speciation rate of modern mammalian biota
<p>Evolutionary rate explanations for latitudinal diversity gradients predict faster speciation and diversification rates in richer, older, and more stable tropical regions (climatic stability hypothesis). Numerous modern lineages have emerged in high latitudes, however, suggesting that climatic oscillations can drive population divergence, at least among extratropical species (glacial refugia hypothesis). This conflicting evidence suggests that geographical patterns of evolutionary rates are more complicated than previously thought.</p> <p>Here, we reconstructed the complex evolutionary dynamics of a comprehensive dataset of modern mammals, both terrestrial and marine. We performed global and regional regression analyses to investigate how climatic instability could have indirectly influenced contemporary diversity gradients through its effects on evolutionary rates. In particular, we explored global and regional patterns of the relationships between species richness and assemblage-level evolutionary rates and between evolutionary rates and climatic instability.</p> <p>We found an inverse relationship between evolutionary rates and species richness, especially in the terrestrial domain. Additionally, climatic instability was strongly associated with the highest evolutionary rates at high terrestrial latitudes, supporting the glacial refugia hypothesis there. At low latitudes, evolutionary rates were unrelated to climatic stability.</p> <p>The inverse relationship between evolutionary rates and the modern latitudinal diversity gradient casts doubt on the idea that higher evolutionary rates in the tropics underlie the current diversity patterns of modern mammals. Alternatively, the longer time spans for diversity to accumulate in the older and more stable tropics (and not high diversification rates) may explain the latitudinal diversity gradient.</p>
Historical quotation of Ibex 35 companies from January 2020 to November 2020
<p>The histogram shows the listing values of Ibex 35 companies from January 2020 to November 2020. There is a histogram for each Ibex 35 company.</p> <p> </p> <p> </p>
B3 Derivatives Prices Historical Data
<p>Historical prices of derivatives obtained from B3 (Bolsa de Valores do Brasil) website.</p> <p>The data are referent to the years 2011 to 2020.</p> <p>The data are separated into 10 .csv files referring to one complete year each.</p>
FIGURE 10. A–E. Reteporella ilala n in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 10. A–E. Reteporella ilala n. sp. A. View of the colony (SAMC-A029168) (scale bar = 10 mm). B. Autozooids surrounding the fenestrula with avicularia along the margins (SAMC-A029107) (scale bar = 0.4 mm, magnified x50). C. Abfrontal view (SAMC-A028899) (scale bar = 0.4 mm, magnified x35). D. Group of autozooids at the growing edge (SAMC-A029107) (scale bar = 0.2 mm, magnified x100). E. Autozooids and avicularia (SAMC-A029107) (scale bar = 0.2 mm, magnified x75).
FIGURE 8. A–E. Hippomonavella lingulata n in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 8. A–E. Hippomonavella lingulata n. sp. (SAMC-A029050) A. Group of autozooids (scale bar = 0.4 mm, magnified x35). B. Close-up of autozooids (scale bar = 0.2 mm, magnified x75). C. Close-up of the orifice, showing condyles and two oral spine bases (scale bar = 0.1 mm, magnified x200). D. Developing ooecium (scale bar = 0.2 mm, magnified x100). E. Ovicelled zooid (scale bar = 0.1 mm, magnified x150).
FIGURE 7. A–E. Adeonella assegai n in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 7. A–E. Adeonella assegai n. sp. (SAMC-A028960) A. Autozooids at the growing edge (scale bar = 0.2 mm, magnified x75). B. Frontal view of autozooids near the margin (scale bar = 0.2 mm, magnified x75). C. Close-up of two zooids (scale bar = 0.2 mm, magnified x100). D. Close-up of the secondary orifice, paired frontal avicularia and spiramen (scale bar = 0.1 mm, magnified x200). E. Dimorphic brooding zooids at the branch margin (scale bar = 0.4 mm, magnified x50).
FIGURE 5. A–F. Trypostega richardi n in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 5. A–F. Trypostega richardi n. sp. A. Group of ovicelled and non-ovicelled autozooids and zooeciules (SAMCA026788) (scale bar = 0.2 mm, magnified x250). B. Close-up of two zooids, one ovicelled. Note the dimorphic orifice in the ovicelled zooid (SAMC-A026788) (scale bar = 0.2 mm, magnified x400). C. Close-up of an ovicell with circular opening of the associated zooeciule (SAMC-A026788) (scale bar = 0.1 mm, magnified x1.0K). D. Cleithridiate orifice with operculum (SAMC-A026788) (scale bar = 0.05 mm, magnified x1.8K). E. Cleithridiate orifice from an angle showing detail of condyles (SAMC-A028976) (scale bar = 0.05 mm, magnified x350). F. Close-up of two zooeciules (SAMC-A028976) (scale bar = 0.1 mm, magnified x200).
FIGURE 4. A–F in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 4. A–F.?Micropora erecta n. sp. A. Group of autozooids (SAMC-A029102) (scale bar = 0.4 mm, magnified x35). B. Autozooids and interzooidal avicularia (SAMC-A029102) (scale bar = 0.2 mm, magnified x75). C. Close-up of the orifice, showing proximal indentations and thickened suboral margin (SAMC-A029102) (scale bar = 0.05 mm, magnified x500). D. Interzooidal avicularia (SAMC-A029102) (scale bar = 0.1 mm, magnified x150). E. Group of ovicelled and non-ovicelled zooids (SAMC-A028821) (scale bar = 0.4 mm, magnified x50). F. Ovicelled zooid (SAMC-A028821) (scale bar = 0.2 mm, magnified x150).
FIGURE 3. A–B. Chaperiopsis familiaris n in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 3. A–B. Chaperiopsis familiaris n. comb. (SAMC-A026415) A. Group of zooids, some with ovicells (scale bar = 0.4 mm, magnified x120). B. Closer view of some ovicelled zooids (scale bar = 0.2 mm, magnified x250). C–F. Aspidostoma sarcophagus n. sp. (SAMC-A029067). C. Zooids and kenozooids with cryptocystal pits (scale bar = 0.5 mm, magnified x35). D. Close-up of the orifice (scale bar = 0.2 mm, magnified x150). E. Developing antler-like processes (scale bar = 0.2 mm, magnified x100). F. Ovicelled zooid with well-developed antler-like processes (zooid on the left) (scale bar = 0.4 mm, magnified x50).
FIGURE 2. A–E. Biflustra adenticulata n in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 2. A–E. Biflustra adenticulata n. sp. A. View of autozooids around the fenestrula (SAMC-A028915) (scale bar = 0.5 mm, magnified x50). B. Smaller, irregular shaped zooids (kenozooids) (SAMC-A028915) (scale bar = 0.1 mm, magnified x200). C. Frontal view of young zooids (SAMC-A028915) (scale bar = 0.2 mm, magnified x100). D. View of zooids near the fenestrula margin (SAMC-A029105) (scale bar = 0.2 mm, magnified x75). E. Multiporous distal mural septula (arrow) and kenozooids on the outer margin (SAMC-A029105) (scale bar = 0.2 mm, magnified x75).
FIGURE 6. A–F. Khulisa carolinae n. gen. et n in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 6. A–F. Khulisa carolinae n. gen. et n. sp. (SAMC-A029002) A. Group of autozooids and interzooidal avicularia (scale bar = 0.4 mm, magnified x50). B. Close-up of the interzooidal avicularium (scale bar = 0.2 mm, magnified x75). C. Autozooids and enlarged dimorphic zooid (scale bar = 0.4 mm, magnified x50). D. View of the apertural bar and detail of the distal pore plates (scale bar = 0.2 mm, magnified x100). E. Close-up of the apertural bar (scale bar = 0.1 mm, magnified x200). F. Orificial rim of an enlarged, dimorphic zooid (scale bar = 0.1 mm, magnified x200).
FIGURE 1 in Novel taxa of Cheilostomata Bryozoa discovered in the historical backlogs of the Iziko South African Museum
FIGURE 1. Map of the southern African sub-region showing the subdivision of the ocean into the Exclusive Economic Zone (EEZ), as a dashed line, indicating four a priori marine bioregions (West, South, Southeast and East Coasts) with some localities mentioned in-text. False Bay in the Western Cape Province and East London in the Eastern Cape Province are considered marine transition zones (i.e. zones lying between two regions).
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These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
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)
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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.