186 research outputs found
Symplectella rowi (Porifera: Hexactinellida: Lyssacinosida) is a rossellid, not a euplectellid
The monospecific hexactinellid sponge genus Symplectella endemic to New Zealand waters was originally assigned to family Rossellidae within the order Lyssacinosida (subclass Hexasterophora), although affinities to family Euplectellidae were also noted. Seventy-eight years later, the genus was transferred to Euplectellidae (subfamily Corbitellinae) on rather subjective grounds. Here, I test these two competing taxonomic hypotheses with molecular phylogenetic methods and demonstrate that Symplectella rowi is indeed a rossellid, as was originally suggested. The genus is officially transferred back to Rossellidae (subfamily Rossellinae), which represents another small step towards a more natural classification system of glass sponges
Dating early animal evolution using phylogenomic data
Information about the geological timeframe during which animals radiated into their major subclades is crucial to understanding early animal ecology and evolution. Unfortunately, the pre-Cambrian fossil record is sparse and its interpretation controversial. Relaxed molecular-clock methods provide an alternative means of estimating the timing of cladogenesis deep in the metazoan tree of life. So far, thorough molecular clock studies focusing specifically on Metazoa as a whole have been based on relatively small datasets or incomplete representation of the main non-bilaterian lineages (such as sponges and ctenophores), which are fundamental for understanding early metazoan evolution. Here, we use a previously published phylogenomic dataset that includes a fair sampling of all relevant groups to estimate the timing of early animal evolution with Bayesian relaxed-clock methods. According to our results, all non-bilaterian phyla, as well as total-group Bilateria, evolved in an ancient radiation during a geologically relatively short time span, before the onset of long-term global glaciations ("Snowball Earth";similar to 720-635 Ma). Importantly, this result appears robust to alterations of a number of important analytical variables, such as models of among-lineage rate variation and sets of fossil calibrations used
Freshwater gobies 30 million years ago: New insights into character evolution and phylogenetic relationships of dagger Pirskeniidae (Gobioidei, Teleostei)
The modern Gobioidei (Teleostei) comprise eight families, but the extinct dagger Pirskeniidae from the lower Oligocene of the Czech Republic indicate that further families may have existed in the past. However, the validity of the dagger Pirskeniidae has been questioned and its single genus dagger Pirskeniushas been assigned to the extant family Eleotridae in previous works. The objective of this study is to clarify the status of the dagger Pirskeniidae. Whether or not the dagger Pirskeniidae should be synonymised with the Eleotridae is also interesting from a biogeographical point of view as Eleotridae is not present in Europe or the Mediterranean Sea today. We present new specimens and re-examine the material on which the two known species of dagger Pirskeniusare based (dagger P.diatomaceusObrhelova, 1961;dagger P.radoniPrikryl, 2014). To provide a context for phylogenetically informative characters related to the palatine and the branchiostegal rays, three early-branching gobioids (Rhyacichthys,Protogobius,Perccottus), an eleotrid (Eleotris) and a gobiid (Gobius) were subjected to micro-CT analysis. The new data justify revalidation of the family dagger Pirskeniidae, and a revised diagnosis is presented for both dagger Pirskeniusand dagger Pirskeniidae. Moreover, we provide for the first time an attempt to relate a fossil gobioid to extant taxa based on phylogenetic analysis. The results indicate a sister-group relationship of dagger Pirskeniidae to the Thalasseleotrididae + Gobiidae + Oxudercidae clade. Considering the fossil record, the arrival of gobioids in freshwater habitats in the early Oligocene apparently had generated new lineages that finally were not successful and became extinct shortly after they had diverged. There is currently no evidence that the Eleotridae was present in the European ichthyofauna in the past
Synthesis of Zeolites from Fine-Grained Perlite and Their Application as Sorbents
The hydrothermal alteration of perlite into zeolites was studied using a two-step approach. Firstly, perlite powder was transformed into Na-P1 (GIS) or hydro(xy)sodalite (SOD) zeolites at 100 °C and 24 h using 2 or 5 M NaOH solutions. Secondly, the Si:Al molar ratio of the reacted Si-rich solution was adjusted to 1 by Na-aluminate addition to produce zeolite A (LTA) at 65 or 95 °C and 6 or 24 h at an efficiency of 90 ± 9% for Al and 93 ± 6% for Si conversion. The performance of these zeolites for metal ion removal and water softening applications was assessed by sorption experiments using an artificial waste solution containing 4 mmol/L of metal ions (Me(2+): Ca(2+), Mg(2+), Ba(2+) and Zn(2+)) and local tap water (2.1 mmol/L Ca(2+) and 0.6 mmol/L Mg(2+)) at 25 °C. The removal capacity of the LTA-zeolite ranged from 2.69 to 2.86 mmol/g for Me(2+) (=240â275 mg/g), which is similar to commercial zeolite A (2.73 mmol/g) and GIS-zeolite (2.69 mmol/g), and significantly higher compared to the perlite powder (0.56 mmol/g) and SOD-zeolite (0.88 mmol/g). The best-performing LTA-zeolite removed 99.8% Ca(2+) and 93.4% Mg(2+) from tap water. Our results demonstrate the applicability of the LTA-zeolites from perlite for water treatment and softening applications
Redox cycling of straw-amended soil simultaneously increases iron oxide crystallinity and the content of highly disordered organo-iron(III) solids
Iron speciation in soils is influenced largely by its redox state, but the extent of and controls on Fe speciation during recurrent reduction and oxidation events are not fully understood. To investigate the effects of organic matter (OM) inputs and the frequency and duration of redox oscillations on soil Fe speciation, we conducted redox-oscillation experiments with topsoil from a Fluvisol mixed with rice straw (0, 10, 50 g/kg organic carbon, OC). The soil was initially dominated by short-range ordered (SRO) Fe(III) solids and subjected to 14- and 28-day reductionâoxidation cycles for 112 days, with the time spent under anoxic and oxic conditions maintained at 6:1. Reduction was initiated by flooding reactors with artificial river water. To simulate leaching conditions, soil re-oxidation was achieved by air-drying soil after removal of reacted solutions. Fresh river water was then added for each new redox cycle. We monitored changes in solution composition (Eh, pH, Fe(II), total Fe, OC, and Si) and assessed changes of solid-phase Fe speciation by selective extractions, X-ray absorption spectroscopy, and 57Fe Mössbauer spectroscopy. Dissolved OC and Fe increased with increasing straw addition, but decreased in each treatment through consecutive reduction intervals. Release rates of dissolved Fe and OC were highly correlated, implying that microbial reduction of soil Fe(III) solids was fostered by straw amendments. Reduction-induced losses of OC and Fe from straw amended soil were amplified at high redox frequency. Ferrous Fe did not detectably accumulate in the solid phase upon repeated soil oxidation. Although Fe(III)-poor phyllosilicates gained in relative importance in redox-cycled soils, their fraction was hardly affected during redox cycling. Instead, straw additions led to an enhanced depletion of ferrihydrite during soil redox cycling and a relative enrichment of highly disordered Fe(III) species [âvery SRO (vSRO) Fe(III) solidsâ], which remained only partially ordered in 5-K Mössbauer spectra and likely consisted predominantly of polynuclear organic Fe complexes. The depletion of ferrihydrite in straw-amended soils after 112 days was greater in the 14-day cycle than in the 28-day cycle experiment and accompanied by a less pronounced enrichment of vSRO Fe(III) solids. The crystallinity of distinct Fe oxides (ferrihydrite, lepidocrocite, and hematite) increased during soil redox cycling especially in straw-amended soils, but without noticeable ferrihydrite conversion into crystalline Fe oxides. The increase in the crystallinity of distinct Fe oxides after 112 days was greater at low redox frequency in straw-free soil, however this frequency effect was suppressed by straw additions. Longer soil redox cycling (112 vs. 56 days) increased the crystallinity of distinct Fe oxides, which was most pronounced at high straw levels and low redox frequency. Our results imply that redox changes in SRO Fe oxide- and OM-rich soils can cause a relative enrichment of more crystalline Fe oxides, while still maintaining a pool of vSRO Fe(III) solids. We conclude that soil redox oscillations can lead to divergent transformation pathways of Fe oxides, which concomitantly increase bulk Fe-oxide crystallinity and generate increasing fractions of highly disordered Fe(III) solids on comparatively short time scales. In addition, our study suggests that faster redox cycling in soils with ample electron donor supply and water leaching leads to higher element exports (e.g., OC, metal(loid)s) from soil due to weekly redox pulsing than more slowly alternating redox conditions
An integrative systematic framework helps to reconstruct skeletal evolution of glass sponges (Porifera, Hexactinellida)
BACKGROUND: Glass sponges (Class Hexactinellida) are important components of deep-sea ecosystems and are of interest from geological and materials science perspectives. The reconstruction of their phylogeny with molecular data has only recently begun and shows a better agreement with morphology-based systematics than is typical for other sponge groups, likely because of a greater number of informative morphological characters. However, inconsistencies remain that have far-reaching implications for hypotheses about the evolution of their major skeletal construction types (body plans). Furthermore, less than half of all described extant genera have been sampled for molecular systematics, and several taxa important for understanding skeletal evolution are still missing. Increased taxon sampling for molecular phylogenetics of this group is therefore urgently needed. However, due to their remote habitat and often poorly preserved museum material, sequencing all 126 currently recognized extant genera will be difficult to achieve. Utilizing morphological data to incorporate unsequenced taxa into an integrative systematics framework therefore holds great promise, but it is unclear which methodological approach best suits this task. RESULTS: Here, we increase the taxon sampling of four previously established molecular markers (18S, 28S, and 16S ribosomal DNA, as well as cytochrome oxidase subunit I) by 12 genera, for the first time including representatives of the order Aulocalycoida and the type genus of Dactylocalycidae, taxa that are key to understanding hexactinellid body plan evolution. Phylogenetic analyses suggest that Aulocalycoida is diphyletic and provide further support for the paraphyly of order Hexactinosida; hence these orders are abolished from the Linnean classification. We further assembled morphological character matrices to integrate so far unsequenced genera into phylogenetic analyses in maximum parsimony (MP), maximum likelihood (ML), Bayesian, and morphology-based binning frameworks. We find that of these four approaches, total-evidence analysis using MP gave the most plausible results concerning congruence with existing phylogenetic and taxonomic hypotheses, whereas the other methods, especially ML and binning, performed more poorly. We use our total-evidence phylogeny of all extant glass sponge genera for ancestral state reconstruction of morphological characters in MP and ML frameworks, gaining new insights into the evolution of major hexactinellid body plans and other characters such as different spicule types. CONCLUSIONS: Our study demonstrates how a comprehensive, albeit in some parts provisional, phylogeny of a larger taxon can be achieved with an integrative approach utilizing molecular and morphological data, and how this can be used as a basis for understanding phenotypic evolution. The datasets and associated trees presented here are intended as a resource and starting point for future work on glass sponge evolution
Genomic data do not support comb jellies as the sister group to all other animals
Understanding how complex traits, such as epithelia, nervous systems, muscles, or guts, originated depends on a well-supported hypothesis about the phylogenetic relationships among major animal lineages. Traditionally, sponges (Porifera) have been interpreted as the sister group to the remaining animals, a hypothesis consistent with the conventional view that the last common animal ancestor was relatively simple and more complex body plans arose later in evolution. However, this premise has recently been challenged by analyses of the genomes of comb jellies (Ctenophora), which, instead, found ctenophores as the sister group to the remaining animals (the âCtenophora-sisterâ hypothesis). Because ctenophores are morphologically complex predators with true epithelia, nervous systems, muscles, and guts, this scenario implies these traits were either present in the last common ancestor of all animals and were lost secondarily in sponges and placozoans (Trichoplax) or, alternatively, evolved convergently in comb jellies. Here, we analyze representative datasets from recent studies supporting Ctenophora-sister, including genome-scale alignments of concatenated protein sequences, as well as a genomic gene content dataset. We found no support for Ctenophora-sister and conclude it is an artifact resulting from inadequate methodology, especially the use of simplistic evolutionary models and inappropriate choice of species to root the metazoan tree. Our results reinforce a traditional scenario for the evolution of complexity in animals, and indicate that inferences about the evolution of Metazoa based on the Ctenophora-sister hypothesis are not supported by the currently available data
Reply to Halanych et al.: Ctenophore misplacement is corroborated by independent datasets
In their letter, Halanych et al. (1) criticize our recent assertion (2) that the phylogenetic placement of ctenophores as the sister group to all other animals (the Ctenophora-sister hypothesis) in three previous studies (3â5) was an artifact caused by undetected systematic error.
Halanych et al. (1) claim we used no âobjective approachesâ to identify sources of systematic error. In fact, we used an objective comparison of Bayesian cross-validation scores to select the best-fitting substitution model, because poorly fitting models are a frequent source of systematic error. Halanych et al. point out that this comparison did not include partitioned site-homogeneous models. However, they do not mention that only one of the studies we address (3) used this approach, and that multiple site-homogeneous partitions still do not account for within-partition site-heterogeneous biochemical constraints, which our results show had a major impact on model fit and the tree topology
Kajian Pengembangan Indikator Kinerja Dinas Pendidikan Kabupaten Kebumen
Public need accurate information concerning problem, education performance indicator and performance indicator that matching with future and public demand. Local government have to can shows the ability and willingness to compile performance indicator of education local-department. Indicator Performance of education local-department have to depict commitment seriously of local government in educating local people. Therefore, this research formulate research question: How improving performance indicator of education local-department at Kebumen Regency that matching with future and public demand? Research with qualitative method have been done. The result of this research are: first, indicator performance compilation of education local-department has to improve in harmony with Medium Level Development Planning (RPJM) Kebumen Regency and key performance indicator for management education which is released by Domestic Department (Departemen Dalam Negeri). Second, education local-department can develop indicators that show incresing of quality and relevance, impact indicators or other additional indicator to assure efficacy activities and programs. Third, training and technical assistance are needed for compilation workplan base on performance to improve knowledge and skilled of governmental officers at education local- department. This is as one of the way to develop performance indicator on education local-department more specific, unique and have high competitiveness
Compositional and Quantitative Insights Into Bacterial and Archaeal Communities of South Pacific Deep-Sea Sponges (Demospongiae and Hexactinellida)
In the present study, we profiled bacterial and archaeal communities from 13 phylogenetically diverse deep-sea sponge species (Demospongiae and Hexactinellida) from the South Pacific by 16S rRNA-gene amplicon sequencing. Additionally, the associated bacteria and archaea were quantified by real-time qPCR. Our results show that bacterial communities from the deep-sea sponges are mostly host-species specific similar to what has been observed for shallow-water demosponges. The archaeal deep-sea sponge community structures are different from the bacterial community structures in that they are almost completely dominated by a single family, which are the ammonia-oxidizing genera within the Nitrosopumilaceae. Remarkably, the archaeal communities are mostly specific to individual sponges (rather than sponge-species), and this observation applies to both hexactinellids and demosponges. Finally, archaeal 16s gene numbers, as detected by quantitative real-time PCR, were up to three orders of magnitude higher than in shallow-water sponges, highlighting the importance of the archaea for deep-sea sponges in general
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