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Fig. 4. Centris hyptidis Ducke, 1908. A–B in The species of the bee genus Centris of the "hyptidis group" revisited with the description of Centris (Anisoctenodes) new subgenus (Hymenoptera: Apidae: Centridini)
Fig. 4. Centris hyptidis Ducke, 1908. A–B. ♀, Brazil, Vitória da Conquista (MNRJ †). C–D.♂, Brazil, Vitória da Conquista (MNRJ †). A, C. Frontal view. B, D. Habitus, lateral view. Scale bars: 1 mm.
Data from: Data set incongruence and correlated character evolution: an example of functional convergence in the hind-limbs of stifftail diving ducks
The unwitting inclusion of convergent characters in phylogenetic estimates poses a serious problem for efforts to recover phylogeny. Convergence is not inscrutable, however, particularly when one group of characters tracks phylogeny and another set tracks adaptive history. In such cases, convergent characters may be correlated with one or a few functional anatomical units and readily identifiable using comparative methods. Stifftail ducks (Oxyurinae) offer one such opportunity to study correlated character evolution and function in the context of phylogenetic reconstruction. Morphological analyses place stifftail ducks as part of a large clade of diving ducks that includes the sea ducks (Mergini), Hymenolaimus, Merganetta, and Tachyeres, and possibly the pochards (Aythyini). Molecular analyses, on the other hand, place stifftails far from other diving ducks and suggest, moreover, that stifftails are polyphyletic. Mitochondrial cytochrome b gene sequences of eight stifftail species traditionally supposed to form a clade were compared with each other and with sequences from 50 other anseriform and galliform species. Stifftail ducks are not the sister group of sea ducks, but lie outside the typical ducks (Anatinae). Of the four traditional stifftail genera, monophyly of Oxyura and its sister group relationship with Nomonyx are strongly supported. Heteronetta probably is the sister group of that clade, but support is weak. Biziura is not a true stifftail. Within Oxyura, Old World species (O. australis, O. leucocephala, O. maccoa) appear to form a clade, with New World species (O. jamaicensis, O. vittata) branching basally. Incongruence between molecules and morphology is interpreted to be the result of adaptive specialization and functional convergence in the hind limbs of Biziura and true stifftails. When morphological characters are divided into classes, only hind-limb characters are significantly in conflict with the molecular tree. Null models of synonomous and nonsynonomous substitution based on patterns of codon-degeneracy and chemical dissimilarity, likewise, indicate that the nucleotide and amino acid changes postulated by the molecular tree are more plausible than those postulated by the morphological tree. These findings teach general lessons about the utility of highly adaptive characters (in particular those related to foraging ecology) and underscore the problems that convergence can pose for attempts to recover phylogeny. They also demonstrate how the concept of natural data partitions and simple models of evolution (e.g., parsimony, likelihood, neutrality) can be used to test the accuracy of independent phylogenetic estimates and provide arguments in favor of one tree topology over another.
Data from: Genetic admixture supports an ancient hybrid origin of the endangered Hawaiian duck
Speciation is regarded primarily as a bifurcation from an ancestral species into two distinct taxonomic units, but gene flow can create different signals of phylogenetic relationships among different loci. We evaluated several hypotheses that could account for phylogenetic discord between mitochondrial DNA (mtDNA) and nuclear DNA (nuDNA) within Hawaiian ducks (Anas wyvilliana), including stochastic lineage sorting, mtDNA capture, and widespread genomic introgression. Our results best support the hypothesis that the contemporary Hawaiian duck is descended from an ancient hybridization event between the mallard (A. platyrhynchos) and Laysan duck (A. laysanensis). Whereas mtDNA clearly shows a sister-relationship between Hawaiian ducks and mallards, nuDNA is consistent with a genetic mosaic with nearly equal contributions from Laysan ducks and mallards. In addition, coalescent analyses suggest that gene flow from either mallard or Laysan duck, depending on the pre-defined tree topology, is necessary to explain contemporary genetic diversity in Hawaiian ducks, and these estimates are more consistent with ancient, rather than contemporary, hybridization. Time since divergence estimates suggest that the genetic admixture event occurred around the Pleistocene-Holocene boundary, which is further supported by circumstantial evidence from the Hawaiian sub-fossil record. Although the extent of reproductive isolation from either putative parental taxon is not currently known, these species are phenotypically, genetically, and ecologically different, and they meet primary criteria used in avian taxonomy for species designation. Thus, the available data are consistent with an admixed origin, and support the hypothesis that the Hawaiian duck may represent a young hybrid species.
Data from: Speciation genomics and a role for the Z chromosome in the early stages of divergence between Mexican ducks and mallards
Speciation is a continuous and dynamic process, and studying organisms during the early stages of this process can aid in identifying speciation mechanisms. The mallard (Anas platyrhynchos) and Mexican duck (A. [p.] diazi) are two recently diverged taxa with a history of hybridization and controversial taxonomy. To understand their evolutionary history, we conducted genomic scans to characterize patterns of genetic diversity and divergence across the mitochondrial DNA (mtDNA) control region, 3523 autosomal loci and 172 Z-linked sex chromosome loci. Between the two taxa, Z-linked loci (ΦST = 0.088) were 5.2 times more differentiated than autosomal DNA (ΦST = 0.017) but comparable to mtDNA (ΦST = 0.092). This elevated Z differentiation deviated from neutral expectations inferred from simulated data that incorporated demographic history and differences in effective population sizes between marker types. Furthermore, 3% of Z-linked loci, compared to <0.1% of autosomal loci, were detected as outlier loci under divergent selection with elevated relative (ΦST) and absolute (dXY) estimates of divergence. In contrast, the ratio of Z-linked and autosomal differentiation among the seven Mexican duck sampling locations was close to 1:1 (ΦST = 0.018 for both markers). We conclude that between mallards and Mexican ducks, divergence at autosomal markers is largely neutral, whereas greater divergence on the Z chromosome (or some portions thereof) is likely the product of selection that has been important in speciation. Our results contribute to a growing body of literature indicating elevated divergence on the Z chromosome and its likely importance in avian speciation.
Data from: Does water temperature affect the timing and duration of remigial moult in sea ducks? An experimental approach
Aquatic birds have high cost of thermoregulation, especially during the moulting period, yet the effect of water temperature on the moulting strategy of aquatic birds has rarely been studied. Our general hypothesis is that energy savings associated with lower thermoregulation costs would be allocated to moulting processes. We predicted that aquatic birds moulting in warm water would have a higher level of body reserves, a faster growth rate of feathers, and an earlier remigial moult onset compared with birds moulting in cold water. We used the common eider (Somateria mollissima dresseri), a large sea duck, as the model species. Captive individuals were experimentally exposed to warm (18 °C) and cold (8 °C) water treatments during a three year period with individuals swapped between treatments. We found a similar feather growth rate for the two water temperature treatments and in contrast to our predictions, eiders exposed to warm water had a lower body mass and showed a delayed onset of remigial moult of approximately 7 days compared with those exposed to cold water. Our data indicate that body mass variations influence the timing of moult in unexpected ways and we suggest that it likely controls the occurrence of wing moult through a hormonal cascade. This study emphasizes the importance of improving our knowledge of the effects of water temperature on remigial moult of aquatic birds, to better assert the potential effects of global warming on their survival.
FIGURES 65–68. 65 in Phylogeny of Protopolybia Ducke, 1905 and taxonomic revision of the Protopolybia exigua species-group (Hymenoptera: Vespidae, Polistinae), with description of four new species
FIGURES 65–68. 65. Protopolybia exigua; 66. P. sedula; 67. P. fuscatus; 68. P. nitida. Mesoscutum.
Bertalanffy's growth curves of A. anatina duck mussels in 18 Polish lakes with reference to living conditions
<p>1. Post-maturation growth leading to indeterminate growth patterns is widespread in nature. However, its adaptive value is unclear. Life history theory suggests this allocation strategy may be favoured by temporal pulses in the intensity of mortality and/or the capacity to produce new tissues.</p> <p>2. Addressing the origin of indeterminate growth and the variability of growth patterns, we studied the growth of duck mussels, <i>Anodonta anatina</i>, a pan-European unionid, in 18 Polish lakes. For each population the sex, size and age of collected mussels were measured to estimate Bertalanffy's growth curve parameters. We integrated information on <i>A. anatina</i> mortality rates, lake trophy, biofouling by zebra mussels, <i>Dreissena polymorpha</i>, and the prevalence of parasitic trematode larvae to identify selective conditions in lakes.</p> <p>3. We found two sources of mortality in <i>A. anatina</i> populations, pertaining to adverse effects of zebra mussel biofouling and trophy state on mussel survival. Additionally, populations with heavier biofouling presented a smaller abundance of parasites, indicative of a relationship between filtering intensity and contraction of water-borne trematode larvae by filtering <i>A. anatina</i>.</p> <p>4. Consistently for each sex, populations with a greater trophy-related mortality were characterized in <i>A. anatina</i> by a smaller asymptotic size <i>L<sub>max</sub></i>, indicative of a life history response to mortality risk involving early maturation at a smaller body size. In all populations, females featured higher mortality and larger asymptotic size <i>vs.</i> males.</p> <p>5. Our findings support a theoretical view that adaptive responses to selection involve adjustments in the lifetime resource allocation patterns. These adjustments should be considered drivers of the origin of indeterminate growth strategy in species taking parental care by offspring brooding in body cavities.</p>
Stable isotope data from: Use of marine vs. freshwater proteins for egg-laying and incubation by sea ducks breeding in Arctic tundra
<p>This data archive contains data used in analyses of protein sources for egg membranes and whole blood of long-tailed ducks (<em>Clangula hyemalis</em>) and Steller's (<em>Polysticta stelleri</em>), spectacled (<em>Somateria fischeri</em>), and king <em>(Somateria spectabilis)</em> eiders. These data have been published in Miller et al. (2022): Use of marine vs. freshwater proteins for egg-laying and incubation by sea ducks breeding in Arctic tundra (Ecosphere).</p>
Figs. 1–10 in Notes on social wasps of the group of Mischocyttarus (Omega) punctatus (Ducke), with description of six new species (Hymenoptera, Vespidae, Polistinae)
Figs. 1–10. Schematic drawings showing proportions and measurements of body parts. 1–6: first metasomal segment in dorsal view respectively of: (1) Mischocyttarus ryani sp. nov.; (2) M. punctatus; (3) M. anchicaya sp. nov.; (4) M. rodriguesi sp. nov.; (5) M. caxiuana sp. nov.; (6) M. verissimoi sp. nov. (length = 2.78 mm); (7) head, frontal; (8) pronotum and mesoscutum, dorsal; (9) mesosoma, lateral; (10) left anterior wing. FHH: height of head; INTOW: distance between eyes at ocular sinus; HCLP, WCLP: height and width of clypeus; WCAR: width of pronotal carina; LMS, WMS: length and width of mesoscutum; HMP: height of mesopleuron; LDIS: length of discal cell of fore wing; LSI,WSI:length and apical width of first metasomal segment.
FIGURE 2. Macrosamanea macrocalyx. A. A. Ducke 16622 in Rediscovery of Macrosamanea macrocalyx (Leguminosae: Mimosoideae), a threatened endemic species from the Middle Xingu River, Amazonia, Brazil
FIGURE 2. Macrosamanea macrocalyx. A. A. Ducke 16622, Isotype (MG). B. J.G. Kuhlmann 2035 (RB).
Effect of wind farms on wintering ducks at an important wintering ground in China along the East Asian-Australasian Flyway
<p>Wind farms offer a cleaner alternative to fossil fuels and can mitigate their negative effects on climate change. However, wind farms may have negative impacts on birds. The East China Coast forms a key part of the East Asian-Australasian Flyway and it is a crucial region for wind energy development in China. However, despite ducks being the dominant animal taxon along the East China Coast in winter and considered as particularly vulnerable to the effects of wind farms, the potential negative impacts of wind farms on duck populations remain unclear. We therefore assessed the effects of wind farms on duck abundance, distribution, and habitat use at Chongming Dongtan, which is a major wintering site for ducks along the East Asian-Australasian Flyway, using field surveys and satellite tracking. We conducted seven paired field surveys of ducks inside (IWF) and outside wind farm (OWF) sites in artificial brackish marsh, paddy fields, and aquaculture ponds. Duck abundance was significantly higher in OWF compared with IWF sites, and significantly higher in artificial brackish marsh than in aquaculture ponds and paddy fields. Based on 1,918 high-resolution satellite tracking records, the main habitat types of ducks during the day and at night were artificial brackish marsh and paddy fields, respectively. Furthermore, grid-based analysis showed overlaps between ducks and wind farms, with greater overlap at night than during the day. According to resource selection functions, habitat use by wintering ducks was impacted by distance to water, land cover, human activity, and wind-farm effects, and the variables predicted to have significant impacts on duck habitat use differed between day and night. Our study suggests that wintering ducks tend to avoid wind turbines at Chongming Dongtan, and landscape of paddy fields and artificial wetlands adjoining natural wetlands is crucial for wintering ducks</p>
Figure 1 from: Diniz F, Silva G, Souza B, Pereira F, Lopes M, Valente S (2014) New molecular evidence for fragmentation between two distant populations of the threatened stingless bee Melipona subnitida Ducke (Hymenoptera, Apidae, Meliponini). Journal of Hymenoptera Research 38: 1-9. https://doi.org/10.3897/jhr.38.7302
Figure 1 - A Sampling sites of Melipona subnitida: NAT (coordinates: 5°48'04"S, 35°11'08"W; State of Rio Grande do Norte) and PAR (coordinates: 2°46'39"S, 41°51'59"W; on the border of the States of Piauí and Maranhão) B Clustering analysis using UPGMA for Melipona subnitida genotypes included in this study based on DICE similarity coefficient values. Numbers indicate bootstrap values for nodes retained by more than 50% of bootstrap replicates (1000 replications) C Scatter-plot of the principal coordinate analysis (PCoA) using ISSR loci. ■ PAR genotypes; ● NAT genotypes D Bar plot from Inferred population structure of using the Bayesian grouping admixture model-based program STRUCTURE (K = 2).
Functional Viability Duck Duck Punch
ClinicalTrials.gov study NCT03053492. IPD Sharing: YES. Countries: 1. Publications: 0.
Data from: Does water temperature affect the timing and duration of remigial moult in sea ducks? An experimental approach
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Data from: Data set incongruence and correlated character evolution: an example of functional convergence in the hind-limbs of stifftail diving ducks
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Data from: Speciation genomics and a role for the Z chromosome in the early stages of divergence between Mexican ducks and mallards
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Effect of wind farms on wintering ducks at an important wintering ground in China along the East Asian-Australasian Flyway
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Data from: Genetic admixture supports an ancient hybrid origin of the endangered Hawaiian duck
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Data from: Convergent evolution on the hypoxia-inducible factor (HIF) pathway genes EGLN1 and EPAS1 in high-altitude ducks
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Bertalanffy's growth curves of A. anatina duck mussels in 18 Polish lakes with reference to living conditions
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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.