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1.
Sci Total Environ ; 938: 173367, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38796011

RESUMO

Community coalescence denotes the amalgamation of biotic and abiotic factors across multiple intact ecological communities. Despite the growing attention given to the phenomenon of coalescence, there remains limited investigation into community coalescence in single and multiple source habitats and its impact on microbial community assemblages in sinks. This study focused on a major river catchment in northern China. We investigated microbial community coalescence across different habitats (i.e., water, sediment, biofilm, and riparian soil) and seasons (i.e., summer and winter). Using 16S rRNA gene amplicon sequence variants, we examined the relationship between community coalescence and microbial diversity, assembly processes, and species coexistence. The results showed that the intensity of microbial community coalescence was higher in the same habitat pairs compared to disparate habitat pairs in both summer and winter. During the occurrence of microbial community coalescence, the assembly processes regulated the intensity of coalescence. When the microbial community exhibited strong heterogeneous selection (heterogeneous environmental conditions leading to more dissimilar community structures), the intensity of community coalescence was low. With the assembly process shifted towards stochasticity, coalescence intensity increased gradually. However, when homogeneous selection (homogeneous environmental conditions leading to more similar community structures) predominantly shaped microbial communities, coalescence intensity exceeded the threshold of 0.25-0.30. Moreover, the enhanced intensity of community coalescence could increase the complexity of microbial networks, thereby enhancing species coexistence. Furthermore, the assembly processes mediated the relationship between community coalescence and species coexistence, underscoring the pivotal role of intermediate intensity of community coalescence in maintaining efficient species coexistence. In conclusion, this study highlights the crucial role of community coalescence originating from single and multiple source habitats in shaping microbial communities in sinks, thus emphasizing its central importance in watershed ecosystems.


Assuntos
Biodiversidade , Microbiota , RNA Ribossômico 16S , Rios , China , Rios/microbiologia , Ecossistema , Monitoramento Ambiental , Estações do Ano
2.
Sci Total Environ ; 912: 168644, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38000755

RESUMO

Harmful algal blooms resulting from eutrophication pose a severe threat to human health. Acetylacetone (AA) has emerged as a potential chemical for combatting cyanobacterial blooms, but its real-world application remains limited. In this study, we conducted a 42-day evaluation of AA's effectiveness in controlling blooms in river water, with a focus on the interplay between ecological community structure, organism functional traits, and water quality. At a concentration of 0.2 mM, AA effectively suppressed the growth of Cyanobacteria (88 %), Bacteroidia (49 %), and Alphaproteobacteria (52 %), while promoting the abundance of Gammaproteobacteria (5.0 times) and Actinobacteria (7.2 times) that are associated with the degradation of organic matter. Notably, after dosing of AA, the OD680 (0.07 ± 0.02) and turbidity (8.6 ± 2.1) remained at a satisfactory level. AA induced significant disruptions in two photosynthesis and two biosynthesis pathways (P < 0.05), while simultaneously enriching eight pathways of xenobiotics biodegradation and metabolism. This enrichment facilitated the reduction of organic pollutants and supported improved water quality. Importantly, AA treatment decreased the abundance of two macrolide-related antibiotic resistance genes (ARGs), ereA and vatE, while slightly increased the abundance of two aminoglycoside-related ARGs, aacA and strB. Overall, our findings establish AA as an efficient and durable algicide with favorable ecological safety. Moreover, this work contributes to the development of effective strategies for maintaining and restoring the health and resilience of aquatic ecosystems impacted by harmful algal blooms.


Assuntos
Cianobactérias , Ecossistema , Humanos , Pentanonas , Eutrofização , Proliferação Nociva de Algas , Lagos/química
3.
Front Microbiol ; 14: 1288066, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094633

RESUMO

Introduction: Understanding microbial communities in diverse ecosystems is crucial for unraveling the intricate relationships among microorganisms, their environment, and ecosystem processes. In this study, we investigated differences in the fungal community structure and diversity in soils from two contrasting climatic and vegetation conditions: the Xinjiang western China plateau and the Fujian southeastern coastal province. Methods: A total of 36 soil samples collected from two climatic regions were subjected to high-throughput ITS gene sequencing for fungal community analysis. In conjunction soil physicochemical properties were assessed and compared. Analyses included an examination of the relationship of fungal community structure to environmental factors and functional profiling of the community structure was using the FUNGuild pipeline. Results: Our data revealed rich fungal diversity, with a total of 11 fungal phyla, 31 classes, 86 orders, 200 families, 388 genera, and 515 species identified in the soil samples. Distinct variations in the physicochemical properties of the soil and fungal community structure were seen in relation to climate and surface vegetation. Notably, despite a colder climate, the rhizosphere soil of Xinjiang exhibited higher fungal (α-)diversity compared to the rhizosphere soil of Fujian. ß-diversity analyses indicated that soil heterogeneity and differences in fungal community structure were primarily influenced by spatial distance limitations and vegetation type. Furthermore, we identified dominant fungal phyla with significant roles in energy cycling and organic matter degradation, including members of the Sordariomycetes, Leotiomycetes, Archaeosporomycetes, and Agaricomycetes. Functional analyses of soil fungal communities highlighted distinct microbial ecological functions in Xinjiang and Fujian soils. Xinjiang soil was characterized by a focus on wood and plant saprotrophy, and endophytes, whereas in Fujian soil the fungal community was mainly associated with ectomycorrhizal interactions, fungal parasitism, and wood saprotrophy. Discussion: Our findings suggest fungal communities in different climatic conditions adapt along distinct patterns with, plants to cope with environmental stress and contribute significantly to energy metabolism and material cycling within soil-plant systems. This study provides valuable insights into the ecological diversity of fungal communities driven by geological and environmental factors.

4.
Microorganisms ; 11(11)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38004740

RESUMO

Antimicrobial resistance is a significant concern worldwide; meanwhile, the impact of 3rd generation cephalosporin (3GC) antibiotics on the microbial communities of cattle and resistance within these communities is largely unknown. The objectives of this study were to determine the effects of two-dose ceftiofur crystalline-free acid (2-CCFA) treatment on the fecal microbiota and on the quantities of second-and third-generation cephalosporin, fluoroquinolone, and macrolide resistance genes in Holstein-Friesian dairy cows in the southwestern United States. Across three dairy farms, 124 matched pairs of cows were enrolled in a longitudinal study. Following the product label regimen, CCFA was administered on days 0 and 3 to cows diagnosed with postpartum metritis. Healthy cows were pair-matched based on lactation number and calving date. Fecal samples were collected on days 0, 6, and 16 and pooled in groups of 4 (n = 192) by farm, day, and treatment group for community DNA extraction. The characterization of community DNA included real-time PCR (qPCR) to quantify the following antibiotic resistance genes: blaCMY-2, blaCTX-M, mphA, qnrB19, and the highly conserved 16S rRNA back-calculated to gene copies per gram of feces. Additionally, 16S rRNA amplicon sequencing and metagenomics analyses were used to determine differences in bacterial community composition by treatment, day, and farm. Overall, blaCMY-2 gene copies per gram of feces increased significantly (p ≤ 0.05) in the treated group compared to the untreated group on day 6 and remained elevated on day 16. However, blaCTX-M, mphA, and qnrB19 gene quantities did not differ significantly (p ≥ 0.05) between treatment groups, days, or farms, suggesting a cephamycinase-specific enhancement in cows on these farms. Perhaps unexpectedly, 16S rRNA amplicon metagenomic analyses showed that the fecal bacterial communities from treated animals on day 6 had significantly greater (p ≤ 0.05) alpha and beta diversity than the untreated group. Two-dose ceftiofur treatment in dairy cows with metritis elevates cephamycinase gene quantities among all fecal bacteria while paradoxically increasing microbial diversity.

5.
Genome Biol Evol ; 15(8)2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37498334

RESUMO

To elucidate the genomic traits of ecological diversification in the Hymenochaetales, we sequenced 15 new genomes, with attention to ectomycorrhizal (EcM) Coltricia species. Together with published data, 32 genomes, including 31 Hymenochaetales and one outgroup, were comparatively analyzed in total. Compared with those of parasitic and saprophytic members, EcM species have significantly reduced number of plant cell wall degrading enzyme genes, and expanded transposable elements, genome sizes, small secreted proteins, and secreted proteases. EcM species still retain some of secreted carbohydrate-active enzymes (CAZymes) and have lost the key secreted CAZymes to degrade lignin and cellulose, while possess a strong capacity to degrade a microbial cell wall containing chitin and peptidoglycan. There were no significant differences in secreted CAZymes between fungi growing on gymnosperms and angiosperms, suggesting that the secreted CAZymes in the Hymenochaetales evolved before differentiation of host trees into gymnosperms and angiosperms. Nevertheless, parasitic and saprophytic species of the Hymenochaetales are very similar in many genome features, which reflect their close phylogenetic relationships both being white rot fungi. Phylogenomic and molecular clock analyses showed that the EcM genus Coltricia formed a clade located at the base of the Hymenochaetaceae and divergence time later than saprophytic species. And Coltricia remains one to two genes of AA2 family. These indicate that the ancestors of Coltricia appear to have originated from saprophytic ancestor with the ability to cause a white rot. This study provides new genomic data for EcM species and insights into the ecological diversification within the Hymenochaetales based on comparative genomics and phylogenomics analyses.


Assuntos
Basidiomycota , Micorrizas , Filogenia , Genômica , Lignina/metabolismo
6.
Ecol Lett ; 26(3): 384-397, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36737422

RESUMO

Understanding community saturation is fundamental to ecological theory. While investigations of the diversity of evolutionary stable states (ESSs) are widespread, the diversity of communities that have yet to reach an evolutionary endpoint is poorly understood. We use Lotka-Volterra dynamics and trait-based competition to compare the diversity of randomly assembled communities to the diversity of the ESS. We show that, with a large enough founding diversity (whether assembled at once or through sequential invasions), the number of long-time surviving species exceeds that of the ESS. However, the excessive founding diversity required to assemble a saturated community increases rapidly with the dimension of phenotype space. Additionally, traits present in communities resulting from random assembly are more clustered in phenotype space compared to random, although still markedly less ordered than the ESS. By combining theories of random assembly and ESSs we bring a new viewpoint to both the saturation and random assembly literature.


Assuntos
Ecossistema , Modelos Biológicos , Evolução Biológica , Fenótipo
7.
Mol Cancer ; 21(1): 182, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36131282

RESUMO

BACKGROUND: Multiple myeloma (MM) is a heterogeneous disease with different patterns of clonal evolution and a complex tumor microenvironment, representing a challenge for clinicians and pathologists to understand and dissect the contribution and impact of polyclonality on tumor progression. METHODS: In this study, we established a global cell ecological landscape of the bone marrow (BM) from MM patients, combining single-cell RNA sequencing and single-molecule long-read genome sequencing data. RESULTS: The malignant mutation event was localized to the tumor cell clusters with shared mutation of ANK1 and IFITM2 in all malignant subpopulations of all MM patients. Therefore, these two variants occur in the early stage of malignant clonal origin to mediate the malignant transformation of proplasmacytes or plasmacytes to MM cells. Tumor cell stemness index score and pseudo-sequential clonal evolution analysis can be used to divide the evolution model of MM into two clonal origins: types I and IX. Notably, clonal evolution and the tumor microenvironment showed an interactive relationship, in which the evolution process is not only selected by but also reacts to the microenvironment; thus, vesicle secretion enriches immune cells with malignant-labeled mRNA for depletion. Interestingly, microenvironmental modification exhibited significant heterogeneity among patients. CONCLUSIONS: This characterization of the malignant clonal evolution pattern of MM at the single-cell level provides a theoretical basis and scientific evidence for a personalized precision therapy strategy and further development of a potential new adjuvant strategy combining epigenetic agent and immune checkpoint blockade.


Assuntos
Mieloma Múltiplo , Medula Óssea/patologia , Evolução Clonal/genética , Humanos , Inibidores de Checkpoint Imunológico , Proteínas de Membrana/genética , Mieloma Múltiplo/patologia , RNA Mensageiro , Microambiente Tumoral/genética
8.
Front Microbiol ; 13: 715637, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185839

RESUMO

Acidobacteria occur in a large variety of ecosystems worldwide and are particularly abundant and highly diverse in soils. In spite of their diversity, only few species have been characterized to date which makes Acidobacteria one of the most poorly understood phyla among the domain Bacteria. We used a culture-independent niche modeling approach to elucidate ecological adaptations and their evolution for 4,154 operational taxonomic units (OTUs) of Acidobacteria across 150 different, comprehensively characterized grassland soils in Germany. Using the relative abundances of their 16S rRNA gene transcripts, the responses of active OTUs along gradients of 41 environmental variables were modeled using hierarchical logistic regression (HOF), which allowed to determine values for optimum activity for each variable (niche optima). By linking 16S rRNA transcripts to the phylogeny of full 16S rRNA gene sequences, we could trace the evolution of the different ecological adaptations during the diversification of Acidobacteria. This approach revealed a pronounced ecological diversification even among acidobacterial sister clades. Although the evolution of habitat adaptation was mainly cladogenic, it was disrupted by recurrent events of convergent evolution that resulted in frequent habitat switching within individual clades. Our findings indicate that the high diversity of soil acidobacterial communities is largely sustained by differential habitat adaptation even at the level of closely related species. A comparison of niche optima of individual OTUs with the phenotypic properties of their cultivated representatives showed that our niche modeling approach (1) correctly predicts those physiological properties that have been determined for cultivated species of Acidobacteria but (2) also provides ample information on ecological adaptations that cannot be inferred from standard taxonomic descriptions of bacterial isolates. These novel information on specific adaptations of not-yet-cultivated Acidobacteria can therefore guide future cultivation trials and likely will increase their cultivation success.

9.
Cogn Res Princ Implic ; 7(1): 7, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35089448

RESUMO

Upon hearing someone's speech, a listener can access information such as the speaker's age, gender identity, socioeconomic status, and their linguistic background. However, an open question is whether living in different locales modulates how listeners use these factors to assess speakers' speech. Here, an audio-visual test was used to measure whether listeners' accentedness judgments and intelligibility (i.e., speech perception) can be modulated depending on racial information in faces that they see. American, British, and Indian English were used as three different English varieties of speech. These speech samples were presented with either a white female face or a South Asian female face. Two experiments were completed in two locales: Gainesville, Florida (USA) and Montreal, Quebec (Canada). Overall, Montreal listeners were more accurate in their transcription of sentences (i.e., intelligibility) compared to Gainesville listeners. Moreover, Gainesville listeners' ability to transcribe the same spoken sentences decreased for all varieties when listening to speech paired with South Asian faces. However, seeing a white or a South Asian face did not impact speech intelligibility for the same spoken sentences for Montreal listeners. Finally, listeners' accentedness judgments increased for American English and Indian English when the visual information changed from a white face to a South Asian face in Gainesville, but not in Montreal. These findings suggest that visual cues for race impact speech perception to a greater degree in locales with greater ecological diversity.


Assuntos
Multilinguismo , Percepção da Fala , Feminino , Identidade de Gênero , Humanos , Idioma , Masculino , Inteligibilidade da Fala , Estados Unidos
10.
Mycoscience ; 62(1): 47-63, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-37090019

RESUMO

The resinicolous fungi Sarea difformis and S. resinae (Sareomycetes) were taxonomically revised on the basis of morphological observations and phylogenetic analyses of the nucleotide sequences of the nSSU-LSU-rpb1-rpb2-mtSSU genes. The results of phylogenetic analyses show that S. difformis and S. resinae are grouped with members of Xylonomycetes. According to the results of phylogenetic analyses and their sexual and asexual morphs resemblance, Sareomycetes is synonymized with Xylonomycetes. Although Tromera has been considered a synonym of Sarea based on the superficial resemblance of the sexual morph, we show that they are distinct genera and Tromera should be resurrected to accommodate T. resinae (= S. resinae). Xylonomycetes was morphologically re-circumscribed to comprise a single family (Xylonaceae) with four genera (Sarea, Trinosporium, Tromera, and Xylona) sharing an endophytic or plant saprobic stage in their lifecycle, ascostroma-type ascomata with paraphysoid, Lecanora-type bitunicate asci, and pycnidial asexual morphs. Phylogenetic analyses based on ITS sequences and environmental DNA (eDNA) implied a worldwide distribution of the species. Although Symbiotaphrinales has been treated as a member of Xylonomycetes in previous studies, it was shown to be phylogenetically, morphologically, and ecologically distinct. We, therefore, treated Symbiotaphrinales as Pezizomycotina incertae sedis.

11.
Microb Ecol ; 81(3): 758-769, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33001224

RESUMO

Soil pH has shown to predict bacterial diversity, but mechanisms are still poorly understood. To investigate how bacteria distribute themselves as a function of soil pH, we assessed community composition, diversity, assembly, and gene abundance across local (ca. 1 km) scale gradients in soil pH from ~ 3.8 to 6.5 created by differences in soil parent material in three northern forests. Plant species were the same on all sites, with no evidence of agriculture in the past. Concentrations of extractable calcium, iron, and phosphorus also varied significantly across the pH gradients. Among taxa, Alphaproteobacteria and Acidobacteria were more common in soils with acidic pH values. Overall richness and diversity of OTUs peaked at intermediate pH values. Variations in OTU richness and diversity also had a quadratic fit with concentrations of extractable calcium and phosphorus. Community assembly was via homogeneous deterministic processes in soils with acidic pH values, whereas stochastic processes dominated in soils with near-neutral pH values. Although we expected selection via genes for acid tolerance response in acidic soils, genes for genetic information processing were more selective. Taxa in higher pH soils had differential abundance of transporter genes, suggesting adaptation to acquire metabolic substrates from soils. Soil bacterial communities in northern forest soils are incredibly diverse, and we still have much to learn about how soil pH and co-varying soil parameters directly drive gene selection in this critical component of ecosystem structure.


Assuntos
Metagenômica , Solo , Bactérias/genética , Biodiversidade , Ecossistema , Florestas , Força Próton-Motriz , Microbiologia do Solo
12.
Trends Ecol Evol ; 34(10): 936-949, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31229335

RESUMO

The ecological diversification of early mammals is one of the most globally transformative events in Earth's history and the Cretaceous Terrestrial Revolution (KTR) and end-Cretaceous mass extinction are commonly hailed as catalysts. However, a confounding issue when examining this diversification is that it comprised nested radiations of mammalian subclades within the broader scope of mammalian evolution. In the past 200 million years, various independent groups experienced large-scale radiations, each involving ecological diversification from ancestral lineages of small insectivores; examples include Jurassic mammaliaforms, Late Cretaceous metatherians, and Cenozoic placentals. Here, we review these ecological radiations, highlighting the nuanced complexity of early mammal evolution, the value of ecomorphological fossil data, and the importance of phylogenetic context in macroevolutionary studies.


Assuntos
Evolução Biológica , Mamíferos , Animais , Extinção Biológica , Fósseis , Filogenia
13.
Front Microbiol ; 10: 708, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31031720

RESUMO

Salmonella enterica subsp. enterica serovar Typhimurium is a common cause of enterocolitis in humans globally, with multidrug resistant (MDR) strains posing an enhanced threat. S. Typhimurium is also a pathogen in food-production animals, and these populations can act as reservoirs of the bacterium. Therefore, surveillance and control measures within food-production animal populations are of importance both to animal and human health and have the potential to be enhanced though improved understanding of the epidemiology of S. Typhimurium within and between food-production animal populations. Here, data from Scotland and national surveillance England and Wales data for isolates from cattle (n = 1115), chickens (n = 248) and pigs (n = 2174) collected between 2003 and 2014 were analyzed. Ecological diversity analyses and rarefaction curves were used to compare the diversity of observed antimicrobial resistance (AMR) profiles between the host species, and within host species populations. Higher AMR profile diversity was observed in isolates from pigs compared to chickens across diversity measures and isolates from cattle for three of four diversity measures. Variation in AMR profile diversity between production sectors was noted, with higher AMR diversity of isolates from broiler compared to layer chickens, breeder compared to rearer and finisher pigs and beef compared to dairy cattle. Findings indicate variation in AMR profile diversity both within and between food-production animal host species. These observations suggest alternate sources of AMR bacteria and/or variation in selective evolutionary pressures within and between food-production animal host species populations.

14.
Proc Natl Acad Sci U S A ; 116(14): 6903-6907, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30886085

RESUMO

Mammals and their closest fossil relatives are unique among tetrapods in expressing a high degree of pectoral girdle and forelimb functional diversity associated with fully pelagic, cursorial, subterranean, volant, and other lifestyles. However, the earliest members of the mammalian stem lineage, the "pelycosaur"-grade synapsids, present a far more limited range of morphologies and inferred functions. The more crownward nonmammaliaform therapsids display novel forelimb morphologies that have been linked to expanded functional diversity, suggesting that the roots of this quintessentially mammalian phenotype can be traced to the pelycosaur-therapsid transition in the Permian period. We quantified morphological disparity of the humerus in pelycosaur-grade synapsids and therapsids using geometric morphometrics. We found that disparity begins to increase concurrently with the emergence of Therapsida, and that it continues to rise until the Permo-Triassic mass extinction. Further, therapsid exploration of new regions of morphospace is correlated with the evolution of novel ecomorphologies, some of which are characterized by changes to overall limb morphology. This evolutionary pattern confirms that nonmammaliaform therapsid forelimbs underwent ecomorphological diversification throughout the Permian, with functional elaboration initially being more strongly expressed in the proximal end of the humerus than the distal end. The role of the forelimbs in the functional diversification of therapsids foreshadows the deployment of forelimb morphofunctional diversity in the evolutionary radiation of mammals.


Assuntos
Evolução Biológica , Linhagem da Célula/fisiologia , Extinção Biológica , Membro Posterior , Mamíferos , Células-Tronco/fisiologia , Animais , Membro Posterior/anatomia & histologia , Membro Posterior/fisiologia , Mamíferos/anatomia & histologia , Mamíferos/fisiologia
15.
Ecol Lett ; 22(4): 572-582, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30648337

RESUMO

A core eco-evolutionary aim is to better understand the factors driving the diversification of functions in ecosystems. Using phylogenetic, trophic, and functional information, we tested whether trophic habits (i.e. feeding guilds) affect lineage and functional diversification in two major radiations of reef fishes. Our results from wrasses (Labridae) and damselfishes (Pomacentridae) do not fully support the 'dead-end' hypothesis that specialisation leads to reduce speciation rates because the tempo of lineage diversification did not substantially vary among guilds in both fish families. Our findings also demonstrate a tight relationship between trophic habits and functional roles held by fish in reef ecosystems, which is not associated with a variation in the tempo of functional diversification among guilds. By illustrating the pivotal importance of the generalist feeding strategy during the evolutionary history of reef fishes, our study emphasises the role of this feeding guild as a reservoir for future diversity.


Assuntos
Ecossistema , Peixes , Perciformes , Animais , Recifes de Corais , Filogenia
16.
Mol Ecol ; 27(24): 5004-5018, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30427085

RESUMO

Genetic diversity is essential for species persistence because it provides the raw material for evolution. For marine organisms, short pelagic larval duration (PLD) and small population size are characteristics generally assumed to associate with low genetic diversity. The ecological diversity of organisms may also affect genetic diversity with an expected corollary that more restricted habitat and dietary requirements could lead to a reduced genetic diversity because of pronounced genetic structuring. Here, we tested whether groups of species with narrower trophic niches displayed lower genetic diversity than those with broader niches. In order to test those predictions, we used different trophic guilds (i.e., groups of species having similar trophic habits) of coral reef damselfishes in Moorea (French Polynesia) for which we determined their genetic diversity using restriction site-associated DNA sequencing (RADseq) and their trophic ecology with stomach contents and stable isotope data. We found that pelagic feeders- the guild picking zooplankton in the water column- exhibited the lowest genetic diversity despite having the longest PLD and the largest population size. This guild had also the lowest variation in habitat characteristics and dietary composition compared to benthic feeders (i.e., those mainly grazing on algae) and the intermediate group (i.e., those feeding on zooplankton, filamentous algae and small benthic invertebrates). Our findings highlight the association between trophic ecology and genetic diversity that should be more commonly investigated in population genetics.


Assuntos
Recifes de Corais , Peixes/genética , Variação Genética , Genética Populacional , Animais , Dieta , Ecologia , Cadeia Alimentar , Conteúdo Gastrointestinal , Larva/crescimento & desenvolvimento , Polinésia , Densidade Demográfica
17.
R Soc Open Sci ; 4(11): 170781, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29291070

RESUMO

Exposed limestone karst landscapes, especially in the tropics, are often home to distinctive and specialized biotas. Among vertebrates, a particularly large number of karst-associated lizard taxa have been described, but for the vast majority, evidence of specific adaptions to karst is lacking. A number of studies, however, have provided evidence of consistent morphological trends in lizards that use complex, three-dimensional, saxicoline habitats such as those that typify karst areas. Here we combine morphological and genetic data to test whether a newly discovered gecko from an extremely rugged karst area in New Guinea shows morphological trends matching those observed in other lizards associated with complex rock habitats such as karst and caves. Consistent with predictions, the new species' head is flatter and narrower than similar-sized relatives, and it has proportionally larger eyes and longer limbs. These trends indicate this taxon represents the second documented instance of karst specialization in a New Guinean vertebrate, and suggest morphological traits to test for evidence of specialized ecological associations in the many karst-associated Cyrtodactylus taxa from Southeast Asia.

18.
Oncotarget ; 7(44): 71123-71135, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27661102

RESUMO

The tumor microenvironment is pivotal in influencing cancer progression and metastasis. Different cells co-exist with high spatial diversity within a patient, yet their combinatorial effects are poorly understood. We investigate the similarity of the tumor microenvironment of 192 local metastatic lesions in 61 ovarian cancer patients. An ecologically inspired measure of microenvironmental diversity derived from multiple metastasis sites is correlated with clinicopathological characteristics and prognostic outcome. We demonstrate a high accuracy of our automated analysis across multiple sites. A low level of similarity in microenvironmental composition is observed between ovary tumor and corresponding local metastases (stromal ratio r = 0.30, lymphocyte ratio r = 0.37). We identify a new measure of microenvironmental diversity derived from Shannon entropy that is highly predictive of poor overall (p = 0.002, HR = 3.18, 95% CI = 1.51-6.68) and progression-free survival (p = 0.0036, HR = 2.83, 95% CI = 1.41-5.7), independent of and stronger than clinical variables, subtype stratifications based on single cell types alone and number of sites. Although stromal influence in ovary tumors is known to have significant clinical implications, our findings reveal an even stronger impact orchestrated by diverse cell types. Quantitative histology-based measures can further enable objective selection of patients who are in urgent need of new therapeutic strategies such as combinatorial treatments targeting heterogeneous tumor microenvironment.


Assuntos
Cistadenocarcinoma Seroso/mortalidade , Neoplasias Ovarianas/mortalidade , Microambiente Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistadenocarcinoma Seroso/patologia , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Ovarianas/patologia , Prognóstico
19.
Proc Natl Acad Sci U S A ; 113(23): 6364-71, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27274043

RESUMO

Recent discoveries of multiple middle Pliocene hominins have raised the possibility that early hominins were as speciose as later hominins. However, debates continue to arise around the validity of most of these new taxa, largely based on poor preservation of holotype specimens, small sample size, or the lack of evidence for ecological diversity. A closer look at the currently available fossil evidence from Ethiopia, Kenya, and Chad indicate that Australopithecus afarensis was not the only hominin species during the middle Pliocene, and that there were other species clearly distinguishable from it by their locomotor adaptation and diet. Although there is no doubt that the presence of multiple species during the middle Pliocene opens new windows into our evolutionary past, it also complicates our understanding of early hominin taxonomy and phylogenetic relationships.


Assuntos
Evolução Biológica , Hominidae/classificação , Animais , Chade , Etiópia , Fósseis , Quênia , Filogenia
20.
Sci Adv ; 2(2): e1500975, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26989775

RESUMO

Patterns of biodiversity are changing rapidly. "Legacy studies" use historical data to document changes between past and present communities, revealing long-term trends that can often be linked to particular drivers of ecological change. However, a single pair of historical samples cannot ascertain whether rates of change are consistent or whether the impact and identity of drivers have shifted. Using data from a second resurvey of 47 Wisconsin prairie remnants, we show that the pace of community change has increased with shifts in the strength of particular drivers. Annual rates of local colonization and extinction accelerated by 129 and 214%, respectively, between 1950 and 1987 and between 1987 and 2012. Two anthropogenic drivers-patch area and fire history-increased in importance between these periods. As the strength and number of anthropogenic forces increase, rates of biodiversity change are likely to accelerate in other ecosystems as well.


Assuntos
Biodiversidade , Pradaria , Ecossistema , Extinção Biológica , Incêndios , Plantas , Fatores de Tempo , Wisconsin
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