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Data from: A population genetic window into the past and future of the walleye Sander vitreus: Relation to historic walleye and the extinct "blue pike" S. v. "glaucus"
Background: Conserving genetic diversity and local adaptations are management priorities for wild populations of exploited species, which increasingly are subject to climate change, habitat loss, and pollution. These constitute growing concerns for the walleye Sander vitreus, an ecologically and economically valuable North American temperate fish with large Laurentian Great Lakes' fisheries. This study compares genetic diversity and divergence patterns across its widespread native range using mitochondrial (mt) DNA control region sequences and nine nuclear DNA microsatellite (μsat) loci, examining historic and contemporary influences. We analyze the genetic and morphological characters of a putative endemic variant– "blue pike" S. v. "glaucus" –described from Lakes Erie and Ontario, which became extinct. Walleye with turquoise-colored mucus are evaluated, since some have questioned whether these are related to the "blue pike". Results: Walleye populations are distinguished by significant considerable genetic divergence (mean FST mtDNA=0.32±0.01, μsat=0.13±0.00) and substantial diversity across their range (mean heterozygosity mtDNA=0.53±0.02, μsat=0.68±0.03). Southern populations markedly differ, possessing unique haplotypes and alleles, especially the . The Ohio/New River population that housespossesses the most pronounced divergence and the oldest haplotype. Northerly formerly glaciated populations have greatest diversity in Lake Erie (mean heterozygosity mtDNA=0.79±0.00, μsat=0.72±0.01). Genetic diversity was much less in historic Lake Erie samples from 1923–1949 (mean heterozygosity mtDNA=0.05±0.01, μsat=0.47±0.06) than today. The historic "blue pike" had no unique haplotypes/alleles and there is no evidence that it comprised a separate taxon from walleye. Turquoise mucus walleye also show no genetic differentiation from other sympatric walleye and no correspondence to the "blue pike". Conclusions: Contemporary walleye populations possess high levels of genetic diversity and divergence, despite habitat degradation and exploitation. Genetic and previously published tagging data indicate that natal homing and spawning site philopatry led to population structure. Population patterns were shaped by climate change and drainage connections, with northern ones tracing to post-glacial recolonization. Southerly populations possess unique alleles and may provide an important future genetic reservoir. Allelic frequencies of Lake Erie walleye from ~70–90 years ago significantly differed from today, suggesting population recovery after extensive habitat loss, pollution, and exploitation. The historic "blue pike" was indistinguishable from walleye, indicating that taxonomic designation is not warranted.
Data from: Present conditions may mediate the legacy effect of past land-use changes on species richness and composition of above- and below-ground assemblages
1. In forest ecosystems, the influence of landscape history on contemporary biodiversity patterns has been shown to provide a convenient framework to explain shifts in plant assemblages. However, very few studies have controlled for present human-induced activities when analyzing the effect of forest continuity on community structures. By cutting and removing trees, foresters substantially change stand ecological conditions, with consequences on biodiversity patterns. Disentangling the effect of past and present human activities on biodiversity is thus crucial for ecosystem management and conservation. 2. We explored the response of plant and springtail species richness and composition to forest continuity (ancient vs recent) in montane forests, while controlling for stand maturity (mature vs overmature). We established 70 sites in landscapes dominated by unfragmented ancient forests where we surveyed plants and assessed springtails by analyzing environmental DNA. 3. Neither plant nor springtail species richness was influenced by forest continuity or by stand maturity. Instead, site-specific characteristics, especially soil properties and canopy openness, were of major importance in shaping above- and below-ground richness. 4. For plant and springtail species composition, the effect of forest continuity was mediated by stand maturity. Thus, both plants and springtails showed a convergence in assemblage patterns with the increasing availability of overmature stand attributes. Moreover, soil and stand-scale factors were evidently more important than landscape-scale factors in shaping above- and below-ground species composition. 5. Synthesis. We clearly demonstrated that biodiversity patterns are more strongly influenced by present human-induced activities than by past human-induced activities. In the Northern Alps where our study sites were located, the colonization credit of most species has been paid off and the transient biodiversity deficit usually related to forest continuity has moved toward equilibrium. These findings emphasize the necessity to better control for local-scale factors when analyzing the response of biodiversity to forest continuity; we call for more research into the effects of forest continuity in unfragmented mountain forests.
Influence of past climate change on phylogeography and demographic history of narwhals, Monodon monoceros
<p>The Arctic is warming <span>at an unprecedented rate,</span> with unknown consequences for endemic fauna. However, Earth has experienced severe climatic oscillations in the past, and understanding how species responded to them might provide insight into their resilience to near-future climatic predictions. Little is known about the responses of Arctic marine mammals to past climatic shifts, but narwhals (<i>Monodon monoceros</i>) are considered one of the endemic Arctic species most vulnerable to environmental change. Here, we analyze 121 complete mitochondrial genomes from narwhals sampled across their range, and use them in combination with species distribution models to elucidate the influence of past and ongoing climatic shifts on their population structure and demographic history. We find low levels of genetic diversity and limited geographic structuring of genetic clades. We show that narwhals experienced a long-term low effective population size, which increased after the Last Glacial Maximum (LGM), when the amount of suitable habitat expanded. Similar post-glacial habitat release has been a key driver of population size expansion of other Polar marine predators. Our analyses indicate that habitat availability has been critical to the success of narwhals, raising concerns for their fate in an increasingly warming Arctic.</p>
FIGURE 11. Bradophila pygmaea Levinsen, 1878 in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 11. Bradophila pygmaea Levinsen, 1878 (♂): A, anterior half of cephalothorax, ventral (A1, antennule; A2, antenna;?Mx1, putative maxillule;?Mx2, putative maxilla; pmp., postmaxillary process; Mxp, maxilliped; o., vestigial oral opening). Melinnacheres levinseni (M'Intosh, 1885): B, habitus ♀, dorsal; C, habitus ♀, ventral (A1, antennule; A2, antenna; Mx2, maxilla; g.a., genital apertures).
FIGURE 10. Bradophila pygmaea Levinsen, 1878 in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 10. Bradophila pygmaea Levinsen, 1878 (♂). A, habitus, lateral (rudimentary legs 1–3 arrowed); B, antenna, dorsal (modified setae arrowed); C, antennule, dorsal (modified setae arrowed).
FIGURE 12. Trophoniphila bradyi M in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 12. Trophoniphila bradyi M'Intosh, 1885 (♀). A, ectosoma and left egg-sac; B, ectosoma, posterior (c.p., copulatory pore; e.s., egg sac string; g.a., genital aperture; g.p., genital papillae; s.r., seminal receptacle; P6, genital operculum derived from sixth leg); C, same, ventral (c.d., copulatory duct; c.p., copulatory pore; s.r., seminal receptacle; P6, genital operculum derived from sixth leg); D, same, lateral (arrow indicating connection with endosoma); E, same, anterior, showing connection with endosome (arrowed stippled area) [inset showing detail of integumental pore].
FIGURE 6. Leaniricola rotundata M in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 6. Leaniricola rotundata M'Intosh, 1885 (♀). A, leg 1, anterior; B, leg 2, anterior; C, leg 3, anterior; D, leg 4.
FIGURE 5. Leaniricola rotundata M in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 5. Leaniricola rotundata M'Intosh, 1885 (♀). A, antennule; B, antenna; C, maxilla; D, maxilliped. Roman numerals in A referring to ancestral antennulary segments (Huys & Boxshall 1991).
FIGURE 3. Leaniricola rotundata M in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 3. Leaniricola rotundata M'Intosh, 1885 (♀). A, habitus, lateral; B, urosome, dorsal; C, urosome, lateral.
FIGURE 1 in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 1. Parasitic copepods described by M'Intosh (1885). A, Leaniricola rotundata; B, Praxillinicola kroyeri; C, Oestrella levinseni; D, Trophoniphila bradyi.
FIGURE 2. Leaniricola rotundata M in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 2. Leaniricola rotundata M'Intosh, 1885 (♀). A, habitus, dorsal (left egg-sac removed); B, cephalothoracic region, ventral (distal portion of labrum and mandibular gnathobases omitted).
FIGURE 8. Praxillinicola kroyeri M in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 8. Praxillinicola kroyeri M'Intosh, 1885 (♀). A, right antennule (A1) and antenna (A2, in reflexed condition); B, same on left side (antennulary claw broken); C, right antennule; D, antennary endopod (right side); E, oral area, showing rostral projection (r.p.), labral retractor muscles (r.m.; only one of three pairs drawn), labral hooks (l.h.) and sensilla (s.); F, maxilliped, anterior; G, maxillipedal endopod, posterior; H, anal somite, showing right genital aperture (g.a.) and anal slit (a.s.), dorsal.
FIGURE 7. Praxillinicola kroyeri M in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 7. Praxillinicola kroyeri M'Intosh, 1885 (♀). A, habitus, dorsal; B, same, ventral, showing position of rostral projection (r.p.), socket containing antennule and antenna (A1 + A2), labrum (Lb.) and maxilliped (Mxp); C, median copulatory pores (c.p.) with remnant of spermatophore neck (r.s.) indicated, ventral.
FIGURE 4. Leaniricola rotundata M in Enigmas from the past: M'Intosh's (1885) annelidicolous copepods from the voyage of H. M. S. Challenger
FIGURE 4. Leaniricola rotundata M'Intosh, 1885 (♀). A, Oral area showing labrum (Lb.), labium (Lm.), mandible (G.: gnathobase) and maxillule (Mx1) [left gnathobase omitted], posterior view; B, same, left lateral view (A2: coxobasis of antenna); C, right caudal ramus, lateral; D, distal portion of left caudal ramus, dorsal.
Data and code for "Nutrient storage links past thermal exposure to current performance in phytoplankton"
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Persistent Influence of Non-Dipole Geomagnetic Field on East Asia over the Past 4,000 Years
<p>A ~4000-year high-resolution full vector (including inc, dec and rpi) paleomagnetic record derived from the Bohai Sea, China.</p>
Is the isotopic composition of precipitation a robust indicator for reconstructions of past tropical cyclones frequency? A case study on Réunion Island from rain and water vapor isotopic observations
<p>Isotopic composition of precipitation and water vapor and LMDZ-iso and ECHAM6-wiso simulations associated with the manuscript:</p> <p>Françoise Vimeux, Camille Risi, Christelle Barthe, Sören François, Alexandre Cauquoin, Olivier Jossoud, Jean-Marc Metzger, Olivier Cattani, Bénédicte Minster, and Martin Werner (2024). Is the isotopic composition of precipitation a robust indicator for reconstructions of past tropical cyclones frequency? A case study on Réunion Island from rain and water vapor isotopic observations. Journal of Geophysical Research: Atmospheres, 129, e2023JD039794. https://doi.org/10.1029/2023JD039794</p>
Data of "Distribution of porosity surrounding a microfiber in cement paste"
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FIGURE 1 in Spider Systematics: Past and Future
FIGURE 1. Species accumulation curves for currently valid spider species, from Clerck to present (solid line) and for currently invalid names (dashed line).
FIGURE 6. Maximum Likelihood tree for Rhinoclemmys melanosterna, R. diademata, R. funerea, R. punctularia and R in Complex phylogeography in Rhinoclemmys melanosterna: conflicting mitochondrial and nuclear evidence suggests past hybridization (Testudines: Geoemydidae)
FIGURE 6. Maximum Likelihood tree for Rhinoclemmys melanosterna, R. diademata, R. funerea, R. punctularia and R. nasuta, based on 3620 bp of nuclear DNA (partial Rag 1, Rag 2, C-mos, R35 and ODC genes). Support values along branches are thorough bootstrap values> 50. Bold branches are supported by posterior probabilities> 0.95 in Bayesian analyses. Note the monophyly of R. melanosterna; lineages I–IV are distributed in the western part, lineages VI and VII in the eastern part of the range.
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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.