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1.
PLoS One ; 15(9): e0235588, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946457

RESUMO

Data on the historical change of the Transbaikalian malacofauna in the Neopleistocene and Holocene is presented. Aquatic mollusc shells from archaeological excavations of the ancient settlements dating from the Neolithic period to Medieval and also from a drill hole of the Neopleistocene alluvial deposits were collected. In total eight species of bivalve molluscs from the families Margaritiferidae, Unionidae, Lymnocardiidae, Glycymerididae [marine], and two gastropod species from families Viviparidae and Planorbidae were identified. These species were aged using radiocarbon dating. It was found that the species ranged in age from more than 50.000 to 2.080-1.210 years BP. Five species inhabited the Transbaikal region which are locally extirpated today. Their disjunctive ranges in the past included southern Europe and Western and Eastern Siberia to Transbaikalia and in the east to Far East and Primorye Territory of Russia. A remarkable finding is that of the bivalve genus Monodacna, which was found very far from its native range, the Ponto-Caspian region. The time of existence and extirpation of the thermophilic species of genera Monodacna, Planorbis, Lanceolaria and Amuropaludina corresponds to cycles of the warming and cooling in Pleistocene and Holocene according to regional climate chronological scales. These species can be used as palaeoclimate indicators. Change of the regional malacofaunal species composition is connected with the natural climatochron cycles in the Pleistocene and Holocene resulting in evidence for succession. In the course of this succession, these stenothermal species became extirpated on a regional level, decreasing their global ranges.


Assuntos
Distribuição Animal , Organismos Aquáticos/fisiologia , Biodiversidade , Ecologia/métodos , Moluscos/fisiologia , Exoesqueleto/química , Animais , Organismos Aquáticos/química , Organismos Aquáticos/classificação , Arqueologia , Europa (Continente) , Extremo Oriente , Fósseis , Água Doce , Geografia , História Antiga , Moluscos/química , Moluscos/classificação , Datação Radiométrica , Sibéria
2.
Nat Commun ; 11(1): 4171, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32820176

RESUMO

Spiralia is a large, ancient and diverse clade of animals, with a conserved early developmental program but diverse larval and adult morphologies. One trait shared by many spiralians is the presence of ciliary bands used for locomotion and feeding. To learn more about spiralian-specific traits we have examined the expression of 20 genes with protein motifs that are strongly conserved within the Spiralia, but not detectable outside of it. Here, we show that two of these are specifically expressed in the main ciliary band of the mollusc Tritia (also known as Ilyanassa). Their expression patterns in representative species from five more spiralian phyla-the annelids, nemerteans, phoronids, brachiopods and rotifers-show that at least one of these, lophotrochin, has a conserved and specific role in particular ciliated structures, most consistently in ciliary bands. These results highlight the potential importance of lineage-specific genes or protein motifs for understanding traits shared across ancient lineages.


Assuntos
Motivos de Aminoácidos/genética , Cílios/genética , Invertebrados/genética , Proteínas/genética , Animais , Anelídeos/classificação , Anelídeos/genética , Anelídeos/fisiologia , Evolução Biológica , Cílios/fisiologia , Comportamento Alimentar/fisiologia , Perfilação da Expressão Gênica/métodos , Invertebrados/classificação , Invertebrados/fisiologia , Larva/genética , Larva/fisiologia , Locomoção/fisiologia , Moluscos/classificação , Moluscos/genética , Moluscos/fisiologia , Filogenia , Especificidade da Espécie
3.
PLoS One ; 15(7): e0235196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32639970

RESUMO

This study contributes to the knowledge of continental fishes recovered from sedimentary successions corresponding to the Bonaerean Stage/Age (late mid-Pleistocene) in the locality of Centinela del Mar, General Alvarado County, Buenos Aires province, Argentina. At this site we describe fossil fishes from a palaeolagoon, including Corydoras sp., Pimelodella sp., Rhamdia sp., Oligosarcus sp., small undetermined characids, Jenynsia sp. and Odontesthes sp. The recovered ichthyofaunal assemblage comprises at least seven taxa of Paranaean lineage. The taxonomic composition of the palaeoichthyofauna is quite comparable to that presently found in Bonaerean Watercourses of the Atlantic Drainage ecoregion. This suggests that local ichthyofaunal communities have remained relatively stable since the late mid-Pleistocene.


Assuntos
Peixes/anatomia & histologia , Fósseis/anatomia & histologia , Animais , Argentina , Ciprinodontiformes/anatomia & histologia , Ciprinodontiformes/classificação , Peixes/classificação , Fósseis/história , Água Doce , História Antiga , Moluscos/anatomia & histologia , Moluscos/classificação
4.
PLoS One ; 15(2): e0228546, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32027712

RESUMO

A cave site Shelter in Smolen III (southern Poland) contains an approximately 2-m-thick stratified sequence of Upper Pleistocene and Holocene clastic sediments, unique for Central Europe. The sequence contents abundant fossil fauna, including mollusk, rodent and bat remains. The cave sites with long profiles of subfossil fauna present a great value for reconstructions of regional terrestrial paleoenvironment. We explore the stratigraphy of this site through analyses of the lithology and geochemistry of sediments, radiocarbon dating of faunal and human remains and charcoals, and archaeological study, as well as the paleoecology derived from the taxonomic composition of fossil faunal assemblages. Our data show that the entire period of the Holocene is recorded in the rockshelter, which makes that site an exceptional and highly valuable case. We present paleoenvironmental reconstructions of regional importance, and we propose to regard Shelter in Smolen III as a regional stratigraphic stratotype of Holocene clastic cave sediments.


Assuntos
Arqueologia/métodos , Cavernas/química , Sedimentos Geológicos/análise , Paleontologia/métodos , Animais , Quirópteros/classificação , Classificação , Bases de Dados Factuais , Europa (Continente) , Fósseis/patologia , História Antiga , Humanos , Moluscos/classificação , Polônia , Roedores/classificação
5.
BMC Evol Biol ; 20(1): 22, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024460

RESUMO

BACKGROUND: Polyplacophora, or chitons, have long fascinated malacologists for their distinct and rather conserved morphology and lifestyle compared to other mollusk classes. However, key aspects of their phylogeny and evolution remain unclear due to the few morphological, molecular, or combined phylogenetic analyses, particularly those addressing the relationships among the major chiton lineages. RESULTS: Here, we present a mitogenomic phylogeny of chitons based on 13 newly sequenced mitochondrial genomes along with eight available ones and RNAseq-derived mitochondrial sequences from four additional species. Reconstructed phylogenies largely agreed with the latest advances in chiton systematics and integrative taxonomy but we identified some conflicts that call for taxonomic revisions. Despite an overall conserved gene order in chiton mitogenomes, we described three new rearrangements that might have taxonomic utility and reconstructed the most likely scenario of gene order change in this group. Our phylogeny was time-calibrated using various fossils and relaxed molecular clocks, and the robustness of these analyses was assessed with several sensitivity analyses. The inferred ages largely agreed with previous molecular clock estimates and the fossil record, but we also noted that the ambiguities inherent to the chiton fossil record might confound molecular clock analyses. CONCLUSIONS: In light of the reconstructed time-calibrated framework, we discuss the evolution of key morphological features and call for a continued effort towards clarifying the phylogeny and evolution of chitons.


Assuntos
Genoma Mitocondrial , Poliplacóforos/classificação , Poliplacóforos/genética , Animais , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Evolução Molecular , Fósseis , Ordem dos Genes , Genoma Mitocondrial/genética , Moluscos/classificação , Moluscos/genética , Filogenia , Análise de Sequência de DNA/métodos
6.
Sci Rep ; 10(1): 101, 2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919367

RESUMO

Relationships among the major lineages of Mollusca have long been debated. Morphological studies have considered the rarely collected Monoplacophora (Tryblidia) to have several plesiomorphic molluscan traits. The phylogenetic position of this group is contentious as morphologists have generally placed this clade as the sister taxon of the rest of Conchifera whereas earlier molecular studies supported a clade of Monoplacophora + Polyplacophora (Serialia) and phylogenomic studies have generally recovered a clade of Monoplacophora + Cephalopoda. Phylogenomic studies have also strongly supported a clade including Gastropoda, Bivalvia, and Scaphopoda, but relationships among these taxa have been inconsistent. In order to resolve conchiferan relationships and improve understanding of early molluscan evolution, we carefully curated a high-quality data matrix and conducted phylogenomic analyses with broad taxon sampling including newly sequenced genomic data from the monoplacophoran Laevipilina antarctica. Whereas a partitioned maximum likelihood (ML) analysis using site-homogeneous models recovered Monoplacophora sister to Cephalopoda with moderate support, both ML and Bayesian inference (BI) analyses using mixture models recovered Monoplacophora sister to all other conchiferans with strong support. A supertree approach also recovered Monoplacophora as the sister taxon of a clade composed of the rest of Conchifera. Gastropoda was recovered as the sister taxon of Scaphopoda in most analyses, which was strongly supported when mixture models were used. A molecular clock based on our BI topology dates diversification of Mollusca to ~546 MYA (+/- 6 MYA) and Conchifera to ~540 MYA (+/- 9 MYA), generally consistent with previous work employing nuclear housekeeping genes. These results provide important resolution of conchiferan mollusc phylogeny and offer new insights into ancestral character states of major mollusc clades.


Assuntos
Teorema de Bayes , Núcleo Celular/genética , Genoma , Genômica/métodos , Moluscos/classificação , Moluscos/genética , Filogenia , Animais , Conjuntos de Dados como Assunto , Especificidade da Espécie
7.
Mol Phylogenet Evol ; 142: 106660, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31639524

RESUMO

For over a decade now, High Throughput sequencing (HTS) approaches have revolutionized phylogenetics, both in terms of data production and methodology. While transcriptomes and (reduced) genomes are increasingly used, generating and analyzing HTS datasets remain expensive, time consuming and complex for most non-model taxa. Indeed, a literature survey revealed that 74% of the molecular phylogenetics trees published in 2018 are based on data obtained through Sanger sequencing. In this context, our goal was to identify the strategy that would represent the best compromise among costs, time and robustness of the resulting tree. We sequenced and assembled 32 transcriptomes of the marine mollusk family Turridae, considered as a typical non-model animal taxon. From these data, we extracted the loci most commonly used in gastropod phylogenies (cox1, 12S, 16S, 28S, h3 and 18S), full mitogenomes, and a reduced nuclear transcriptome representation. With each dataset, we reconstructed phylogenies and compared their robustness and accuracy. We discuss the impact of missing data and the use of statistical tests, tree metrics, and supertree and supermatrix methods to further improve phylogenetic data acquisition pipelines. We evaluated the overall costs (time and money) in order to identify the best compromise for phylogenetic data sampling in non-model animal taxa. Although sequencing full mitogenomes seems to constitute the best compromise both in terms of costs and node support, they are known to induce biases in phylogenetic reconstructions. Rather, we recommend to systematically include loci commonly used for phylogenetics and taxonomy (i.e. DNA barcodes, rRNA genes, full mitogenomes, etc.) among the other loci when designing baits for capture.


Assuntos
Filogenia , Animais , Custos e Análise de Custo , Perfilação da Expressão Gênica , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Moluscos/classificação , Moluscos/genética , Análise de Sequência de DNA
8.
Cienc. tecnol. salud ; 7(1): 62-77, 2020. ^c27 cmilus
Artigo em Espanhol | LILACS | ID: biblio-1120437

RESUMO

Los moluscos son uno de los grupos faunísticos dominantes en ambientes estuarinos con bosque de manglar como el humedal Las Lisas-La Barrona. Forman parte de la transferencia de energía a través de las redes tróficas y contribuyen a la estructuración de los hábitats bénticos. El humedal Las Lisas-La Barrona se ubica en el litoral Pacífico de Guatemala. Se determinó la diversidad de la comunidad de moluscos, así como su relación con los parámetros fisicoquímicos del agua. Se realizaron ocho muestreos (enero a agosto) en 2017, utilizando parcelas con un área de 16 m2 en seis sitios de bosque de manglar y cuatro sitios en el canal estuarino, distribuidos en el humedal. La riqueza de moluscos del humedal está comprendida por 26 especies correspondientes a 18 familias y 22 géneros. Las especies más abundantes de gasterópodos fueron Cerithideopsis californica (Adams, 1852) y Littoraria fasciata (Gray, 1839) y de bivalvos Iliochione subrugosa (Wood, 1828) y Larkinia grandis (Broderip & Sowerby, 1829). Los sitios correspondientes a bosque de manglar presentaron una mayor cantidad de moluscos, principalmente gasterópodos. La distribución de las especies dominantes, no está dada por los factores fisicoquímicos del agua, pudiendo ser otros factores como la disponibilidad de hábitat y alimento los que rijan su distribución dentro del humedal. Algunos factores como la influencia de agua marina dentro del humedal, las altas concentraciones de oxígeno disuelto y pH ligeramente básicos, así como la calidad del agua en general, hacen del humedal Las Lisas-La Barrona un área muy diversa en cuanto a especies de moluscos.


Molluscs are one of the dominant faunistic groups in estuarine environments with mangrove forests such as the Las Lisas-La Barrona wetland. They are part of the transfer of energy through trophic networks and contribute to the structuring of the benthic habitats. The Las Lisas-La Barrona wetland is located on the Pacific coast of Guatemala. The diversity of the mollusk community, as well as its relationship with the physicochemical parameters of the water was determined. Eight samplings were carried out (January to August) in 2017, using parcels with an area of 16 m2 in six mangrove forest sites and four sites in the estuarine channel, distributed along the wetland. The mollusk richness of the wetland is comprised of 26 species corresponding to 18 families and 22 genera. The most abundant species of gastropods were Cerithideopsis californica (Adams, 1852) and Littoraria fasciata (Gray, 1839) and bivalves Iliochione subrugosa (Wood, 1828) and Larkinia grandis (Broderip & Sowerby, 1829). The sites corresponding to mangrove forest, presented a greater amount of mollusks, mainly gastropods. The distribution of dominant species is not given by the physicochemical factors of the water, being able to be other factors such as the availability of habitat and food that govern their distribution within the wetland. Some factors such as the influence of seawater in the wetland, the high concentrations of dissolved oxygen and the slightly basic levels of pH, as well as water quality in general, make the Las Lisas-La Barrona wetland a very diverse area in terms of mollusk species


Assuntos
Animais , Costa , Fauna Bentônica/análise , Áreas Alagadas , Moluscos/classificação , Qualidade da Água , Bivalves , Estuários , Gastrópodes
9.
BMC Genomics ; 20(1): 937, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805848

RESUMO

BACKGROUND: Nicotinic acetylcholine receptors (nAChRs) are among the oldest and most conserved transmembrane receptors involved in signal transduction. Despite the prevalence and significance of cholinergic signaling, the diversity and evolution of nAChRs are not fully understood. RESULT: By comparative genomic analysis, we found massive expansions of nAChR genes in molluscs and some other lophotrochozoans. The expansion is particularly pronounced in stationary bivalve molluscs with simple nervous systems, with the number of nAChR genes ranging from 99 to 217 in five bivalves, compared with 10 to 29 in five ecdysozoans and vertebrates. The expanded molluscan nAChR genes tend to be intronless and in tandem arrays due to retroposition followed by tandem duplication. Phylogenetic analysis revealed diverse nAChR families in the common ancestor of bilaterians, which subsequently experienced lineage-specific expansions or contractions. The expanded molluscan nAChR genes are highly diverse in sequence, domain structure, temporal and spatial expression profiles, implying diversified functions. Some molluscan nAChR genes are expressed in early development before the development of the nervous system, while others are involved in immune and stress responses. CONCLUSION: The massive expansion and diversification of nAChR genes in bivalve molluscs may be a compensation for reduced nervous systems as part of adaptation to stationary life under dynamic environments, while in vertebrates a subset of specialized nAChRs are retained to work with advanced nervous systems. The unprecedented diversity identified in molluscs broadens our view on the evolution and function of nAChRs that are critical to animal physiology and human health.


Assuntos
Perfilação da Expressão Gênica/métodos , Moluscos/genética , Receptores Nicotínicos/química , Receptores Nicotínicos/genética , Animais , Evolução Molecular , Duplicação Gênica , Regulação da Expressão Gênica , Humanos , Íntrons , Moluscos/classificação , Família Multigênica , Filogenia , Domínios Proteicos
10.
PLoS One ; 14(12): e0226527, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31841568

RESUMO

DNA-based identification through the use of metabarcoding has been proposed as the next step in the monitoring of biological communities, such as those assessed under the Water Framework Directive (WFD). Advances have been made in the field of metabarcoding, but challenges remain when using complex samples. Uneven biomass distributions, preferential amplification and reference database deficiencies can all lead to discrepancies between morphological and DNA-based taxa lists. The effects of different taxonomic groups on these issues remain understudied. By metabarcoding WFD monitoring samples, we analyzed six different taxonomic groups of freshwater organisms, both separately and combined. Identifications based on metabarcoding data were compared directly to morphological assessments performed under the WFD. The diversity of taxa for both morphological and DNA-based assessments was similar, although large differences were observed in some samples. The overlap between the two taxon lists was 56.8% on average across all taxa, and was highest for Crustacea, Heteroptera, and Coleoptera, and lowest for Annelida and Mollusca. Taxonomic sorting in six basic groups before DNA extraction and amplification improved taxon recovery by 46.5%. The impact on ecological quality ratio (EQR) scoring was considerable when replacing morphology with DNA-based identifications, but there was a high correlation when only replacing a single taxonomic group with molecular data. Different taxonomic groups provide their own challenges and benefits. Some groups might benefit from a more consistent and robust method of identification. Others present difficulties in molecular processing, due to uneven biomass distributions, large genetic diversity or shortcomings of the reference database. Sorting samples into basic taxonomic groups that require little taxonomic knowledge greatly improves the recovery of taxa with metabarcoding. Current standards for EQR monitoring may not be easily replaced completely with molecular strategies, but the effectiveness of molecular methods opens up the way for a paradigm shift in biomonitoring.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Código de Barras de DNA Taxonômico/métodos , Monitorização de Parâmetros Ecológicos/métodos , Invertebrados/classificação , Invertebrados/genética , Animais , Anelídeos/classificação , Anelídeos/genética , Biodiversidade , Biota/genética , Crustáceos/classificação , Crustáceos/genética , DNA/análise , Bases de Dados Factuais , Água Doce/química , Moluscos/classificação , Moluscos/genética , Reprodutibilidade dos Testes , Qualidade da Água/normas
11.
Brief Funct Genomics ; 18(6): 377-394, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31609407

RESUMO

Gastropods are the largest and most diverse class of mollusc and include species that are well studied within the areas of taxonomy, aquaculture, biomineralization, ecology, microbiome and health. Gastropod research has been expanding since the mid-2000s, largely due to large-scale data integration from next-generation sequencing and mass spectrometry in which transcripts, proteins and metabolites can be readily explored systematically. Correspondingly, the huge data added a great deal of complexity for data organization, visualization and interpretation. Here, we reviewed the recent advances involving gastropod omics ('gastropodomics') research from hundreds of publications and online genomics databases. By summarizing the current publicly available data, we present an insight for the design of useful data integrating tools and strategies for comparative omics studies in the future. Additionally, we discuss the future of omics applications in aquaculture, natural pharmaceutical biodiscovery and pest management, as well as to monitor the impact of environmental stressors.


Assuntos
Gastrópodes/classificação , Gastrópodes/genética , Genômica/métodos , Moluscos , Filogenia , Animais , Aquicultura/métodos , Ecossistema , Sequenciamento de Nucleotídeos em Larga Escala , Metabolômica/métodos , Moluscos/classificação , Moluscos/genética , Filogeografia , Proteômica/métodos
12.
Commun Biol ; 2: 280, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31372519

RESUMO

Coleoidea (squids and octopuses) comprise all crown group cephalopods except the Nautilida. Coleoids are characterized by internal shell (endocochleate), ink sac and arm hooks, while nautilids lack an ink sac, arm hooks, suckers, and have an external conch (ectocochleate). Differentiating between straight conical conchs (orthocones) of Palaeozoic Coleoidea and other ectocochleates is only possible when rostrum (shell covering the chambered phragmocone) and body chamber are preserved. Here, we provide information on how this internalization might have evolved. We re-examined one of the oldest coleoids, Gordoniconus beargulchensis from the Early Carboniferous of the Bear Gulch Fossil-Lagerstätte (Montana) by synchrotron, various lights and Reflectance Transformation Imaging (RTI). This revealed previously unappreciated anatomical details, on which we base evolutionary scenarios of how the internalization and other evolutionary steps in early coleoid evolution proceeded. We suggest that conch internalization happened rather suddenly including early growth stages while the ink sac evolved slightly later.


Assuntos
Evolução Biológica , Fósseis , Moluscos/anatomia & histologia , Moluscos/classificação , Animais , Filogenia
13.
Proc Natl Acad Sci U S A ; 116(36): 17659-17665, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31427519

RESUMO

Crystallization by particle attachment (CPA) of amorphous precursors has been demonstrated in modern biomineralized skeletons across a broad phylogenetic range of animals. Precisely the same precursors, hydrated (ACC-H2O) and anhydrous calcium carbonate (ACC), have been observed spectromicroscopically in echinoderms, mollusks, and cnidarians, phyla drawn from the 3 major clades of eumetazoans. Scanning electron microscopy (SEM) here also shows evidence of CPA in tunicate chordates. This is surprising, as species in these clades have no common ancestor that formed a mineralized skeleton and appear to have evolved carbonate biomineralization independently millions of years after their late Neoproterozoic divergence. Here we correlate the occurrence of CPA from ACC precursor particles with nanoparticulate fabric and then use the latter to investigate the antiquity of the former. SEM images of early biominerals from Ediacaran and Cambrian shelly fossils show that these early calcifiers used attachment of ACC particles to form their biominerals. The convergent evolution of biomineral CPA may have been dictated by the same thermodynamics and kinetics as we observe today.


Assuntos
Exoesqueleto/metabolismo , Biomineralização/fisiologia , Carbonato de Cálcio/metabolismo , Cnidários , Equinodermos , Moluscos , Animais , Cnidários/classificação , Cnidários/metabolismo , Equinodermos/classificação , Equinodermos/metabolismo , Fósseis , Moluscos/classificação , Moluscos/metabolismo
14.
PLoS One ; 14(6): e0218086, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31188894

RESUMO

The evaluation of large amounts of digital image data is of growing importance for biology, including for the exploration and monitoring of marine habitats. However, only a tiny percentage of the image data collected is evaluated by marine biologists who manually interpret and annotate the image contents, which can be slow and laborious. In order to overcome the bottleneck in image annotation, two strategies are increasingly proposed: "citizen science" and "machine learning". In this study, we investigated how the combination of citizen science, to detect objects, and machine learning, to classify megafauna, could be used to automate annotation of underwater images. For this purpose, multiple large data sets of citizen science annotations with different degrees of common errors and inaccuracies observed in citizen science data were simulated by modifying "gold standard" annotations done by an experienced marine biologist. The parameters of the simulation were determined on the basis of two citizen science experiments. It allowed us to analyze the relationship between the outcome of a citizen science study and the quality of the classifications of a deep learning megafauna classifier. The results show great potential for combining citizen science with machine learning, provided that the participants are informed precisely about the annotation protocol. Inaccuracies in the position of the annotation had the most substantial influence on the classification accuracy, whereas the size of the marking and false positive detections had a smaller influence.


Assuntos
Ciência do Cidadão/métodos , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Biologia Marinha/métodos , Animais , Organismos Aquáticos , Artrópodes/anatomia & histologia , Artrópodes/classificação , Cnidários/anatomia & histologia , Cnidários/classificação , Equinodermos/anatomia & histologia , Equinodermos/classificação , Humanos , Imageamento Tridimensional , Biologia Marinha/instrumentação , Moluscos/anatomia & histologia , Moluscos/classificação , Poríferos/anatomia & histologia , Poríferos/classificação
15.
PLoS One ; 14(6): e0215668, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242180

RESUMO

Over the last two decades, much of the recent efforts dedicated to the Levantine Middle Paleolithic has concentrated on the role of open-air sites in the settlement system in the region. Here focus on the site of 'Ein Qashish as a cases study. Located in present-day northern Israel, the area of this site is estimated to have been >1300 m2, of which ca. 670 were excavated. The site is located at the confluence of the Qishon stream with a small tributary running off the eastern flanks of the Mt. Carmel. At the area of this confluence, water channels and alluvial deposits created a dynamic depositional environment. Four Archaeological Units were identified in a 4.5-m thick stratigraphic sequence were dated by Optically Stimulated Luminescence (OSL) to between-71 and 54 ka, and probably shorter time span-~70-~60 ka. Here we present the diverse material culture remains from the site (lithics, including refitted sequences; modified limestone pieces; molluscs; faunal remains) against their changing paleogeographic backdrop. Skeletal evidence suggests that these remains were associated with Neanderthals. The large-scale repeated accumulation of late Middle Paleolithic remains in the same place on the landscape provides a unique opportunity to address questions of occupation duration and intensity in open-air sites. We find that each occupation was of ephemeral nature, yet presents a range of activities, suggesting that the locale has been used as a generalized residential site rather than specialized task-specific ones. This role of 'Ein Qashish did not change through time, suggesting that during the late Middle Paleolithic settlement system in this part of the southern Levant were stable.


Assuntos
Fósseis/anatomia & histologia , Homem de Neandertal/anatomia & histologia , Animais , Israel , Moluscos/anatomia & histologia , Moluscos/classificação
16.
Sci Rep ; 9(1): 6977, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-31061398

RESUMO

Based on the specimens collected during three deep-sea cruises, and deposited at the Muséum National d'Histoire Naturelle (MNHN) in Paris, we analysed the diversity of benthic communities within the EEZ of French Polynesia. The literature and the MNHN database allowed us to inventory 471 species of invertebrates, among which 169 were newly described. We mainly found data for Mollusca, Crustacea, Brachiopoda and Crinoidea. We also found samples from other taxa, which still remain unidentified within the collections of the MNHN. Although this inventory is incomplete, we demonstrate that the deep waters of French Polynesia host unique benthic communities and endemic species. Using diversity and multivariate analyses, we show that the deep-sea benthic communities are structured by depth, habitats, geography and also by the presence of polymetallic crust. Furthermore, by focusing on the molluscs of the central area of French Polynesia, we show that the spectrum of shell size differs among deep-sea habitats. Specifically, shells tend to be smaller on encrusted seamounts than on island slopes. Together with the size range of organisms, low abundance, rarity and endemism designate these habitats as sensitive. These results should thus be taken into account in the evaluation of the expected impact of mining activities on biological communities.


Assuntos
Crustáceos/crescimento & desenvolvimento , Ecossistema , Meio Ambiente , Sedimentos Geológicos/química , Metais/química , Moluscos/crescimento & desenvolvimento , Animais , Crustáceos/classificação , Moluscos/classificação , Oceanos e Mares
17.
Sci Total Environ ; 676: 206-214, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31048152

RESUMO

Climate-related factors (e.g. environmental energy, water availability and climatic seasonality/variability) and habitat heterogeneity have long been considered as the main drivers of species diversity on a broad spatial scale. However, it is controversial whether the above environmental factors can explain observed diversity patterns in varied communities such as invertebrate taxonomic group, especially mollusks. Moreover, there are until now few systematic assessments of the relative roles of different factors in determining the patterns of mollusk species diversity in monsoon-dominated regions. Here, we depict variations in terrestrial mollusk diversity based on a dataset comprising 282 assemblages collected from surface soils along an ~800-km climatic gradient from subtropical to warm temperate and mid-temperate regions in northern China. The results show that mollusk species diversity increases significantly from ~3-4 species to ~17-19 species when annual temperature and precipitation increase up to ~12 °C and ~700 mm, respectively; however, at or above these values the rate of increase is reduced. These indicate that the relationships between mollusk species diversity and climatic factors are nonlinear. Statistical analysis suggests that water availability (relative humidity) and temperature seasonality (January temperature and annual temperature range) dominate the observed pattern of mollusk species diversity. Moreover, habitat factors such as vegetation condition and soil types were also important in determining mollusk species diversity. They may be an indirect reflection of the effects of monsoonal water-energy dynamic on mollusk communities. Our results suggest that more attention should be paid to water availability and temperature seasonality in predicting future biodiversity changes, especially in the environmentally stressed northwestern part of the East Asian monsoon region.


Assuntos
Biodiversidade , Monitoramento Ambiental , Moluscos/fisiologia , Animais , China , Moluscos/classificação , Estações do Ano , Tempo (Meteorologia)
18.
J AOAC Int ; 102(5): 1330-1338, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30940285

RESUMO

Background: Fish and fish products are one of the most important food sources of high commercial interest. The global food trade and the associated risks are constantly presenting new challenges to consumer protection and public authorities, which, among other things, demand state-of-the-art analytical methods to ensure food authenticity. Objective: The establishment of MS-based strategies plays a decisive role alongside the (further) development of ELISA- or DNA-oriented methods. Methods: In the present work, therefore, the development and in-house validation of an LC-MS and LC-MS/MS-based assay for authenticity testing of certain fish species is described. Results: Based on the execution of a validated bottom-up LC-electrospray-MS and MS/MS assay and multivariate analysis, the commercially available species Lutjanus malabaricus (red snapper) and Sebastes spp. (redfish) are distinguished from each other, whereas an additional 68 samples [nine additional marine species such as pangasius (Pangasianodon hypophthalmus), salmon (Salmo salar), turbot (Scophthalmus maximus), plaice (Pleuronectes platessa), sole (Solea solea), lemon sole (Glyptocephalus cynoglossus), halibut (Reinhardtius hypoglossoides), red salmon (Oncorhynchus nerka), and great scallop (Pecten jacobaeus)] served as blinded negative controls to ensure the specificity of the assay. Conclusions and Highlights: A promising LC-MS and LC-MSMS based assay has been developed that could enable the detection of fish fraud at the protein level in the future.


Assuntos
Cromatografia Líquida/métodos , Proteínas de Peixes/análise , Peixes/classificação , Peptídeos/análise , Espectrometria de Massas em Tandem/métodos , Animais , Moluscos/classificação , Redes Neurais de Computação , Análise de Componente Principal
19.
Mol Phylogenet Evol ; 135: 249-269, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30780003

RESUMO

Fissurellidae are marine gastropods with a worldwide distribution and a rich fossil record. We integrate molecular, geographical and fossil data to reconstruct the fissurellid phylogeny, estimate divergence times and investigate historical routes of oceanic dispersal. With five molecular markers for 143 terminals representing 27 genera, we resolve deep nodes and find that many genera (e.g., Emarginula, Diodora, Fissurella) are not monophyletic and need systematic revision. Several genera classified as Emarginulinae are recovered in Zeidorinae. Future work should prioritize emarginuline genera to improve understanding of ancestral traits and the early evolution of fissurellids. Tree calibration with the fossilized birth-death model indicates that crown fissurellids originated around 175 Ma, and generally resulted in younger ages for the earliest nodes than the node dating approach. Model-based biogeographic reconstruction, supported by fossils, infers an Indo-West Pacific origin, with a westward colonization of new oceans via the Tethys Seaway upon the breakup of Pangea. Western Atlantic clades then served as source for dispersal towards other parts of the globe. As the sister group to all other fissurellids, Rimula is ranked in its own subfamily, Rimulinae stat. nov. New synonyms: Hemitominae syn. nov. of Zeidorinae stat. nov.; Cranopsissyn. nov. of Puncturella; Variegemarginulasyn. nov. of Montfortula.


Assuntos
Organismos Aquáticos/classificação , Internacionalidade , Moluscos/classificação , Filogenia , Filogeografia , Animais , Biodiversidade , Fósseis , Modelos Biológicos
20.
Artigo em Inglês | MEDLINE | ID: mdl-30660987

RESUMO

Cellular signaling initiated by various secreted, cysteine-rich Wnt proteins plays essential roles in regulating animal development and cell stemness. By virtue of its functional diversity and importance, the Wnt gene family has received substantial research interests in a variety of animal species, from invertebrates to vertebrates. However, for bivalve molluscs, one of the ancient bilaterian groups with high morphological diversity, systematic identification and analysis of the Wnt gene family remain lacking. To shed some light on the evolutionary dynamics of this gene family and obtain a more comprehensive understanding, we analyzed the characteristics of the Wnt gene family in three bivalve molluscs, with both genome and extensive transcriptomic resources. Investigation of genomic signatures, functional domains as well as phylogenetic relationships was conducted, and 12, 11, 12 subfamilies were identified in Yesso scallop, Zhikong scallop and Pacific oyster respectively. Spatiotemporal expression profiling suggested that, some bivalve Wnts might coordinate and participate in adult organ/tissue morphogenesis and homeostasis as well as early embryonic development. The transcriptional regulation of oyster Wnt genes showed dynamic and responsive patterns under different environmental stresses, indicating that Wnts may play a role in coping with challenging intertidal environments in bivalves. To our best knowledge, this study presents the first genome-wide study of Wnt gene family in bivalves, and our findings would assist in better understanding of Wnt function and evolution in bivalve molluscs.


Assuntos
Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Moluscos/genética , Proteínas Wnt/genética , Animais , Evolução Biológica , Moluscos/classificação , Filogenia
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