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The coordination of behaviours between mates is a central aspect of the biology of the monogamous pair bonding in birds. This coordination may rely on intrapair acoustic communication, which is surprisingly poorly understood. Here we examined the impact of an increased level of background noise on intrapair acoustic communication at the nest in the zebra finch, Taeniopygia guttata. We monitored how partners adapted their acoustic interactions in response to a playback of wind noise inside the nestbox during incubation. Both zebra finch parents incubate and use coordinated call duets when they meet at the nest. The incubating parent can vocalize to its partner either outside the nestbox (sentinel duets) or inside the nestbox (relief and visit duets), depending on the context of the meeting. Pairs use these duets to communicate on predation threats (sentinel duets), incubation duties (relief) and other nesting activities (visit duets). Each of these duets probably represents a critical component of pair coordination. In response to the noise playback, partners called less and more rapidly during visit and relief duets. Female and male calls were more regularly and precisely alternated during relief duets. Mates increased the number of visit duets and their spatial proximity during sentinel duets. Furthermore, both females and males produced louder, higher-frequency and less broadband calls. Taken together our results show that birds use several strategies to adjust to noise during incubation, underlining the importance of effective intrapair communication for breeding pairs.
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The intercontinental distribution of living freshwater osteoglossiform fishes (Osteoglossomorpha, Teleostei) was hypothesized to predominantly represent the vicariant result of the fragmentation of Gondwana based on physiological and phylogenetic evidence. The fossil record, however, challenges this hypothesis by making transoceanic dispersal plausible because it provides post-fragmentation minimum ages of intercontinental clades and it includes several marine forms. The aim of this study was to test whether the divergence of Osteoglossiformes was compatible with the breakup of Gondwana using newly reconstructed time-calibrated phylogenetic trees based on a large dataset combining extant and fossil taxa and molecular and morphological characters. Bayesian tip-dating and node-dating approaches with different Teleostei age calibrations were employed. The results of the divergence tests are largely dependent on the a priori calibrated age of crown-group Teleostei, with two of the three specific vicariance hypotheses tested in this study not being rejected only when the age of the Teleostei was constrained to be as old as the early Permian. Molecules consistently push the age of crown-group Teleostei back to the Paleozoic, while the fossil record, which is considered informative, does not support such an ancient origin. Reconciling molecular and paleontological estimates of the age of crown-group Teleostei is central to determining the role of Gondwanan breakup in the intercontinental distribution of freshwater teleosts, including Osteoglossiformes.
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The Groupe Européen de Recherches Gazières (GERG) 2008 multi-parameter equation of state (EOS) is considered the reference model for the prediction of natural gas mixture properties. However, the limited quality of thermodynamic property data available for many key binary mixtures at the time of its development constrained both its range of validity and achievable uncertainty. The data situation for the binary system (CH4+C4H10) in particular was identified previously as limiting the ability of the GERG-EOS to describe rich natural gases at low temperatures. Recently, new vapour-liquid equilibrium (VLE) and liquid mixture heat capacity data measured at low temperatures and high pressures have been published that significantly improve the data situation for this crucial binary, allowing erroneous literature data to be identified and the predictive behaviour of the GERG-EOS when extrapolated to be tested. The 10 basis functions in the generalised departure function used by the GERG-EOS for several binaries including (CH4+C4H10) were examined to eliminate the term causing a divergence between measured and predicted liquid mixture isobaric heat capacities at T<150K. With a simplified nine-term departure function, the maximum relative deviation between the measured and predicted heat capacities was reduced from nearly (110 to 7) %. The interaction parameters in the GERG equation were also re-determined by including, for the first time for this binary, reliable low temperature VLE data together with most of the other high temperature data used in the original development of the model. The new interaction parameters for (CH4+C4H10) reduced the relative deviation of bubble point pressures measured and calculated at T=244K from (9 to 1.4) %, without affecting the accuracy of property predictions at higher temperatures.
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Nassariidae are a group of scavenging, predominantly marine, snails that are diversified on soft bottoms as well as on rocky shores, and are the subject of numerous research papers in ecology, ecotoxicology or paleontology. A weak and/or apparently continuous variation in shell characters has resulted in an intimidating taxonomy, with complex synonymy lists. Over 1320 extant nominal species have been described, of which 442 are currently regarded as valid. Above species level, the state of the art is equally hazy, with four subfamilies and twelve genera currently accepted, and many other names in the graveyard of synonymy. A molecular analysis based on three mitochondrial (COI, 16S, 12S) and two nuclear (28S, H3) markers was conducted. Our dataset includes 218 putative nassariid species, comprising 9 of the 12 valid genera, and 25 nominal genera represented by their type species. The monophyly of the Nassariidae as classically construed is not confirmed. Species of Antillophos, Engoniophos, Phos, Nassaria, Tomlinia and Anentome (formerly considered Buccinidae) are included inside the Nassariidae clade. Within the Nassariinae, the tree unexpectedly demonstrates that species from the Atlantic and the Indo-Pacific form different clades which represent several independent diversification events. Through an integrative approach, the reconstruction of ancestral states was addressed for eight characters supposedly informative for taxonomy. Using numerous fossil calibration points, Nassariidae appear to have originated 120 MYA ago in Atlantic temperate waters during the Lower Cretaceous. Our results have a profound impact on nassariid taxonomy, especially with regard to the validity of subfamily- and genus-level names.
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The phase diagrams of NdBr3–MBr (M=Li…Cs) pseudobinary systems measured by different authors show discrepancies. Therefore in the present work mentioned systems have been re-examined and the compatibility of their phase diagrams have been evaluated. The dependences of mixing enthalpies on NdBr3 mole fraction, heat capacities of M3NdBr6 intermediate compounds (M=Li…Cs) formed in the investigated systems and evaluated phase diagrams have been used for optimization of coupled phase diagrams. The experimental data have been used to predict of an unknown thermodynamic properties of M2NdBr5 and MNd2Br7 (M=Li…Cs) intermediate compounds. The Associate Model of the liquid phase has been applied and the dependence of mixing entropy on NdBr3 mole fraction for the set of the phase diagrams have been found. The amount of the main associate {3M++NdBr63−} in each system has been estimated.
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The neogastropod family Fasciolariidae Gray, 1853 – tulips, horse-conchs, spindles, etc., comprises important representatives of tropical and subtropical molluscan assemblages, with over 500 species in the subfamilies Fasciolariinae Gray, 1853, Fusininae Wrigley, 1927 and Peristerniinae Tryon, 1880. Fasciolariids have had a rather complicated taxonomical history, with several genus names for a long time used as waste baskets to group many unrelated species; based on shell characters, recent taxonomic revisions have, however, began to set some order in its taxonomy. The present work is the first molecular approach to the phylogeny of Fasciolariidae based on a multigene dataset, which provides support for fasciolariids, an old group with a fossil record dating back to the Cretaceous. Molecular markers used were the mitochondrial genes 16S rRNA and cytochrome c oxidase subunit I, and the nuclear genes 18S rRNA, 28S rRNA and histone H3, sequenced for up to 116 ingroup taxa and 17 outgroups. Phylogenetic analyses revealed monophyly of Dolicholatirus Bellardi, 1884 and Teralatirus Coomans, 1965, however it was not possible to discern if the group is the sister clade to the remaining fasciolariids; the latter, on the other hand, proved monophyletic and contained highly supported groups. A first split grouped fusinines and Pseudolatirus Bellardi, 1884; a second split grouped the peristerniine genera Peristernia Mörch, 1852 and Fusolatirus Kuroda and Habe, 1971, while the last group comprised fasciolariines and the remaining peristerniines. None of these clades correspond to the present-day accepted circumscription of the three recognized subfamilies.
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Allatostatin-type A (AST-A), kisspeptin (KISS) and galanin (GAL) G-protein coupled receptor (GPCR) systems share a common ancestral origin in arthropods and the vertebrates where they regulate metabolism and reproduction. The molluscs are the second most diverse phylum in the animal kingdom, they occupy an important phylogenetic position, and their genome is more similar to deuterostomes than the arthropods and nematodes and thus they are good models for studies of gene family evolution and function. This mini-review intends to extend the current knowledge about AST-A, KISS and GAL GPCR system evolution and their putative function in the mollusc mantle. Comparative evolutionary analysis of the target GPCR systems was established by identifying homologues in genomes and tissue transcriptome datasets available for molluscs and comparing them to those of other metazoan systems. Studies in arthropods have revealed the existence of the AST-A system but the loss of homologues of the KISS and GAL systems. Homologues of the insect AST-AR and vertebrate KISSR genes were found in molluscs but putative GALR genes were absent. Receptor gene number suggested that members of this family have suffered lineage specific evolution during the molluscan radiation. In molluscs, orthologues of the insect AST-A peptides were not identified but buccalin peptides that are structurally related were identified and are putative receptor agonists. The identification of AST-AR and KISSR genes in molluscs strengthens the hypotheses that in metazoans members of the AST-AR subfamily share evolutionary proximity with KISSRs. The variable number of receptors and large repertoire of buccalin peptides may be indicative of the functional diversity of the AST-AR/KISSR systems in molluscs. The identification of AST-A and KISS receptors and ligands in the mantle transcriptome indicates that in molluscs they may have acquired a novel function and may play a role in shell development or sensory detection in the mantle.
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Action-theoretic views of language posit that the recognition of others’ intentions is key to successful interpersonal communication. Yet, speakers do not always code their intentions literally, raising the question of which mechanisms enable interlocutors to exchange communicative intents. The present study investigated whether and how prosody—the vocal tone—contributes to the identification of “unspoken” intentions. Single (non-)words were spoken with six intonations representing different speech acts—as carriers of communicative intentions. This corpus was acoustically analyzed (Experiment 1), and behaviorally evaluated in two experiments (Experiments 2 and 3). The combined results show characteristic prosodic feature configurations for different intentions that were reliably recognized by listeners. Interestingly, identification of intentions was not contingent on context (single words), lexical information (non-words), and recognition of the speaker’s emotion (valence and arousal). Overall, the data demonstrate that speakers’ intentions are represented in the prosodic signal which can, thus, determine the success of interpersonal communication.
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The Fourier transform infrared (FTIR) spectrum of the c-type ν8 band of 13C2HD3 was recorded for the first time at a unapodized resolution of 0.0063cm−1 in the wavenumber region of 830–1000cm−1. Through the fitting of a total of 1057 assigned infrared transitions using Watson’s A-reduced Hamiltonian in the Ir representation, rovibrational constants for the upper state (v8=1) up to five quartic centrifugal distortion terms were derived for the first time with a root-mean-square (rms) deviation of 0.00073cm−1. The band center of ν8 of 13C2HD3 was found to be 913.011021(55)cm−1. Ground state rovibrational constants up to five quartic terms of 13C2HD3 were also determined from a fit of 453 ground state combination-differences from the present infrared measurements with an rms deviation of 0.00072cm−1 for the first time. The uncertainty of the measured infrared lines was estimated to be ±0.0012cm−1. From the ground state rotational constants, the inertial defect of 13C2HD3 was calculated to be 0.06973(16)uÅ2, showing the high planarity of the molecule.
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The chloroplast genomes of green algae are highly variable in their architecture. In this article we summarize gene content across newly obtained and published chloroplast genomes in Chlorophyceae, including new data from nine of species in Sphaeropleales (Chlorophyceae, Chlorophyta). We present genome architecture information, including genome synteny analysis across two groups of species. Also, we provide a phylogenetic tree obtained from analysis of gene order data for species in Chlorophyceae with fully sequenced chloroplast genomes. Further analyses and interpretation of the data can be found in “Chloroplast phylogenomic data from the green algal order Sphaeropleales (Chlorophyceae, Chlorophyta) reveal complex patterns of sequence evolution” (Fučíková et al., In review) [1].
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