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1.
Mol Phylogenet Evol ; 197: 108083, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38679303

RESUMO

Kinosternon is the most speciose genus of extant turtles, with 22 currently recognized species, distributed across large parts of the Americas. Most species have small distributions, but K. leucostomum and K. scorpioides range from Mexico to South America. Previous studies have found discordance between mitochondrial and nuclear phylogenies in some kinosternid groups, with the current taxonomy following the nuclear-based results. Herein, based on extended molecular, geographic, and taxonomic sampling, we explore the phylogeographic structure and taxonomic limits for K. leucostomum and the K. scorpioides group and present a fossil-calibrated nuclear time tree for Kinosternon. Our results reveal contrasting differentiation patterns for the K. scorpioides group and K. leucostomum, despite overlapping distributions. Kinosternon leucostomum shows only shallow geographic divergence, whereas the K. scorpioides group is polyphyletic with up to 10 distinct taxa, some of them undescribed. We support the elevation of K. s. albogulare and K. s. cruentatum to species level. Given the deep divergence within the genus Kinosternon, we propose the recognition of three subgenera, Kinosternon, Cryptochelys and Thyrosternum, and the abandonment of the group-based classification, at least for the K. leucostomum and K. scorpioides groups. Our results show an initial split in Kinosternon that gave rise to two main radiations, one Nearctic and one mainly Neotropical. Most speciation events in Kinosternon occurred during the Quaternary and we hypothesize that they were mediated by both climatic and geological events. Additionally, our data imply that at least three South American colonizations occurred, two in the K. leucostomum group, and one in the K. scorpioides group. Additionally, we hypothesize that discordance between mitochondrial and nuclear phylogenetic signal is due to mitochondrial capture from an extinct kinosternine lineage.


Assuntos
Filogenia , Filogeografia , Tartarugas , Animais , Tartarugas/classificação , Tartarugas/genética , América do Sul , Núcleo Celular/genética , DNA Mitocondrial/genética , Análise de Sequência de DNA , Tipagem de Sequências Multilocus , Variação Genética , Teorema de Bayes
2.
J Fluoresc ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38805133

RESUMO

The development of luminescent coordination polymers for the selective sensing of Pb2+ in water constitutes an active area of research that impacts analytical, environmental, and inorganic chemistry. Herein, two novel water-stable 2D Zn-coordination polymers {[Zn2(H2O)2(tdc)2(bpy)]·(H2O)}n 1 and [Zn(tdc)(tmb)]n 2 (tdc = thiophenedicarboxylate; bpy = 4,4'-bipyridine and tmb = 4,4'-trimethylenebipyridine) were synthesized, structurally determined by single crystal X-ray diffraction, and studied in-depth as luminescent sensors for a series of cations (Ca2+, Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+ Cd2+, Hg2+ and Pb2+) in 20% aqueous ethanol. These Zn-polymers possess photostability in 20% aqueous ethanol with a strong emission at 410 upon excitation at 330 nm and quantum yields of around Φ = 0.09. Under these conditions, Pb+2 can be efficiently sensed with polymer 2 through a fluorescent ratiometric response with selectivity over common interfering metal ions such as Cu2+, Cd2+ and Hg2+ in the micromolar concentration range (detection limit = 1.78 ± 10 µM). Such selectivity/affinity of Pb2+ over Hg2+ for luminescent chemosensors is still rare. On the basis of spectroscopic tools (1H NMR, far ATR-IR, PXRD), the X-ray crystal structure of 2, and Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopic analysis, the ratiometric fluorescent response is proposed via an efficient metal-ion exchange driven through interactions between thiophenedicarboxylate rings and Pb2+ ions. The use of flexible luminescent Zn-coordination polymers as sensors for selective and direct detection of Pb2+ in aqueous media has been unexplored until now.

3.
Ecol Lett ; 26(4): 609-620, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36855287

RESUMO

Tropical montane communities host the world's highest beta diversity of birds, a phenomenon usually attributed to community turnover caused by changes in biotic and abiotic factors along elevation gradients. Yet, empirical data on most biotic factors are lacking. Nest predation is thought to be especially important because it appears to be common and can change selective pressures underlying life history traits, which can alter competitive interactions. We monitored 2538 nests, 338 of which had known nest predators, to evaluate if nest predation changes along a tropical elevational gradient. We found that nest predation decreased with elevation, reflecting the loss of lowland predators that do not tolerate colder climates. We found different "super" nest predators at each elevation that accounted for a high percentage of events, suggesting that selection pressures exerted by nest predator communities may be less diffuse than has been hypothesized, at least for birds nesting in the understory.


Assuntos
Comportamento de Nidação , Comportamento Predatório , Animais , Aves
4.
PLoS Comput Biol ; 18(7): e1010164, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35862309

RESUMO

Conferences are spaces to meet and network within and across academic and technical fields, learn about new advances, and share our work. They can help define career paths and create long-lasting collaborations and opportunities. However, these opportunities are not equal for all. This article introduces 10 simple rules to host an inclusive conference based on the authors' recent experience organizing the 2021 edition of the useR! statistical computing conference, which attracted a broad range of participants from academia, industry, government, and the nonprofit sector. Coming from different backgrounds, career stages, and even continents, we embraced the challenge of organizing a high-quality virtual conference in the context of the Coronavirus Disease 2019 (COVID-19) pandemic and making it a kind, inclusive, and accessible experience for as many people as possible. The rules result from our lessons learned before, during, and after the organization of the conference. They have been written mainly for potential organizers and selection committees of conferences and contain multiple practical tips to help a variety of events become more accessible and inclusive. We see this as a starting point for conversations and efforts towards building more inclusive conferences across the world. * Translated versions of the English abstract and the list of rules are available in 10 languages in S1 Text: Arabic, French, German, Italian, Japanese, Korean, Portuguese, Spanish, Tamil, and Thai.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Índia , Itália , Pandemias , Redação
5.
Am J Dermatopathol ; 45(2): 99-106, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36669073

RESUMO

INTRODUCTION: Leprosy is an ancient and chronic infectious disease caused by 2 mycobacteria (Mycobacterium leprae and Mycobacterium lepromatosis). Recently, our research group observed that HES-1, an innate cellular component of the Notch signaling pathway, is related to the pathogenesis of leprosy. Therefore, it could be helpful in its detection. OBJECTIVE: To determine the expression of HES-1 in the skin of patients with paucibacillary (PB) leprosy. METHODS: A cross-sectional, descriptive, observational study was conducted. Forty-five skin samples from patients with leprosy were evaluated (30 samples from MB leprosy and 15 from PB leprosy) using immunohistochemistry of HES-1 and S-100. RESULTS: PB leprosy biopsies revealed a reduction of HES-1 in 66.7% of the epidermis, 80% of the eccrine glands, and 62.5% of the hair follicles of these patients, with statistical differences in the control group (P < 0.0001). Besides, HES-1 showed similar utility to S-100 immunostaining in detecting the MB and PB leprosy. CONCLUSIONS: HES-1 is a transcriptional factor also reduced in PB patients' epidermis and skin appendages. Finally, our data show that HES-1 could be a biomarker in diagnosing PB and MB leprosy.


Assuntos
Hanseníase Multibacilar , Hanseníase Paucibacilar , Hanseníase , Humanos , Fatores de Transcrição , Fatores de Transcrição HES-1 , Estudos Transversais , Sensibilidade e Especificidade , Mycobacterium leprae , Hanseníase Multibacilar/microbiologia
6.
Proc Natl Acad Sci U S A ; 117(8): 4273-4280, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32054783

RESUMO

Bacillus anthracis, the etiological agent of anthrax, is a well-established model organism. For B. anthracis and most other infectious diseases, knowledge regarding transmission and infection parameters in natural systems, in large part, comprises data gathered from closely controlled laboratory experiments. Fatal, natural anthrax infections transmit the bacterium through new host-pathogen contacts at carcass sites, which can occur years after death of the previous host. For the period between contact and death, all of our knowledge is based upon experimental data from domestic livestock and laboratory animals. Here we use a noninvasive method to explore the dynamics of anthrax infections, by evaluating the terminal diversity of B. anthracis in anthrax carcasses. We present an application of population genetics theory, specifically, coalescence modeling, to intrainfection populations of B. anthracis to derive estimates for the duration of the acute phase of the infection and effective population size converted to the number of colony-forming units establishing infection in wild plains zebra (Equus quagga). Founding populations are small, a few colony-forming units, and infections are rapid, lasting roughly between 1 d and 3 d in the wild. Our results closely reflect experimental data, showing that small founding populations progress acutely, killing the host within days. We believe this method is amendable to other bacterial diseases from wild, domestic, and human systems.


Assuntos
Antraz/transmissão , Antraz/veterinária , Bacillus anthracis/fisiologia , Equidae/microbiologia , Animais , Antraz/microbiologia , Bacillus anthracis/genética , Modelos Animais de Doenças , Humanos , Modelos Biológicos , Mutação
7.
Proc Natl Acad Sci U S A ; 113(19): 5340-5, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27118837

RESUMO

The area and thickness of respiratory surfaces, and the constraints they impose on passive oxygen diffusion, have been linked to differences in oxygen consumption rates and/or aerobic activity levels in vertebrates. However, it remains unclear how respiratory surfaces and associated diffusion rates vary with body mass across vertebrates, particularly in relation to the body mass scaling of oxygen consumption rates. Here we address these issues by first quantifying the body mass dependence of respiratory surface area and respiratory barrier thickness for a diversity of endotherms (birds and mammals) and ectotherms (fishes, amphibians, and reptiles). Based on these findings, we then use Fick's law to predict the body mass scaling of oxygen diffusion for each group. Finally, we compare the predicted body mass dependence of oxygen diffusion to that of oxygen consumption in endotherms and ectotherms. We find that the slopes and intercepts of the relationships describing the body mass dependence of passive oxygen diffusion in these two groups are statistically indistinguishable from those describing the body mass dependence of oxygen consumption. Thus, the area and thickness of respiratory surfaces combine to match oxygen diffusion capacity to oxygen consumption rates in both air- and water-breathing vertebrates. In particular, the substantially lower oxygen consumption rates of ectotherms of a given body mass relative to those of endotherms correspond to differences in oxygen diffusion capacity. These results provide insights into the long-standing effort to understand the structural attributes of organisms that underlie the body mass scaling of oxygen consumption.


Assuntos
Índice de Massa Corporal , Peso Corporal/fisiologia , Modelos Biológicos , Consumo de Oxigênio/fisiologia , Oxigênio/metabolismo , Troca Gasosa Pulmonar/fisiologia , Animais , Metabolismo Basal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Simulação por Computador , Difusão , Peixes , Humanos , Especificidade da Espécie
8.
Proc Biol Sci ; 284(1849)2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28202808

RESUMO

Differences in the limits and range of aerobic activity levels between endotherms and ectotherms remain poorly understood, though such differences help explain basic differences in species' lifestyles (e.g. movement patterns, feeding modes, and interaction rates). We compare the limits and range of aerobic activity in endotherms (birds and mammals) and ectotherms (fishes, reptiles, and amphibians) by evaluating the body mass-dependence of VO2 max, aerobic scope, and heart mass in a phylogenetic context based on a newly constructed vertebrate supertree. Contrary to previous work, results show no significant differences in the body mass scaling of minimum and maximum oxygen consumption rates with body mass within endotherms or ectotherms. For a given body mass, resting rates and maximum rates were 24-fold and 30-fold lower, respectively, in ectotherms than endotherms. Factorial aerobic scope ranged from five to eight in both groups, with scope in endotherms showing a modest body mass-dependence. Finally, maximum consumption rates and aerobic scope were positively correlated with residual heart mass. Together, these results quantify similarities and differences in the potential for aerobic activity among ectotherms and endotherms from diverse environments. They provide insights into the models and mechanisms that may underlie the body mass-dependence of oxygen consumption.


Assuntos
Anfíbios/metabolismo , Aves/metabolismo , Peixes/metabolismo , Mamíferos/metabolismo , Consumo de Oxigênio , Répteis/metabolismo , Aerobiose , Animais , Filogenia
9.
Zootaxa ; 3785: 201-16, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24872178

RESUMO

We describe a new species of Anolis from the Magdalena river valley in Colombia. The new species is morphologically similar to Anolis ibanezi and A. chocorum, but differs in body and dewlap color, and head scalation. We performed an exploratory multivariate analysis based on 15 morphological characteristics of the new species and A chocorum and found that differences between both species are mainly associated with head dimensions. A phylogenetic analysis based on morphological characters suggests that the new species is nested within the "Dactyloa" clade of Anolis. Finally, we discuss phylogenetic relationships and biogeographical affinities based in its distribution. 


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Animais , Colômbia , Demografia , Feminino , Lagartos/genética , Masculino , Filogenia , Especificidade da Espécie
10.
Viruses ; 16(5)2024 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-38793647

RESUMO

(1) Background: Epizootic hemorrhagic disease virus (EHDV) and bluetongue virus (BTV) are orbiviruses that cause hemorrhagic disease (HD) with significant economic and population health impacts on domestic livestock and wildlife. In the United States, white-tailed deer (Odocoileus virginianus) are particularly susceptible to these viruses and are a frequent blood meal host for various species of Culicoides biting midges (Diptera: Ceratopogonidae) that transmit orbiviruses. The species of Culicoides that transmit EHDV and BTV vary between regions, and larval habitats can differ widely between vector species. Understanding how midges are distributed across landscapes can inform HD virus transmission risk on a local scale, allowing for improved animal management plans to avoid suspected high-risk areas or target these areas for insecticide control. (2) Methods: We used occupancy modeling to estimate the abundance of gravid (egg-laden) and parous (most likely to transmit the virus) females of two putative vector species, C. stellifer and C. venustus, and one species, C. haematopotus, that was not considered a putative vector. We developed a universal model to determine habitat preferences, then mapped a predicted weekly midge abundance during the HD transmission seasons in 2015 (July-October) and 2016 (May-October) in Florida. (3) Results: We found differences in habitat preferences and spatial distribution between the parous and gravid states for C. haematopotus and C. stellifer. Gravid midges preferred areas close to water on the border of well and poorly drained soil. They also preferred mixed bottomland hardwood habitats, whereas parous midges appeared less selective of habitat. (4) Conclusions: If C. stellifer is confirmed as an EHDV vector in this region, the distinct spatial and abundance patterns between species and physiological states suggest that the HD risk is non-random across the study area.


Assuntos
Animais Selvagens , Vírus Bluetongue , Ceratopogonidae , Cervos , Vírus da Doença Hemorrágica Epizoótica , Insetos Vetores , Infecções por Reoviridae , Animais , Ceratopogonidae/virologia , Ceratopogonidae/fisiologia , Vírus da Doença Hemorrágica Epizoótica/fisiologia , Cervos/virologia , Insetos Vetores/virologia , Insetos Vetores/fisiologia , Vírus Bluetongue/fisiologia , Animais Selvagens/virologia , Infecções por Reoviridae/transmissão , Infecções por Reoviridae/veterinária , Infecções por Reoviridae/virologia , Ecossistema , Estações do Ano , Fazendas , Aves/virologia
11.
An Bras Dermatol ; 99(4): 491-502, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38521707

RESUMO

BACKGROUND: Skin modification through tattoos is as old as humanity itself. However, this trend is on the rise, and with the use of different types of pigments and application practices, both cutaneous and systemic complications can arise. Adverse reactions can be grouped into five classes: inflammatory, infectious, neoplastic, aesthetic, and miscellaneous. On histopathology, inflammatory reactions can exhibit a lichenoid pattern or present as spongiotic dermatitis, granulomatous reactions, pseudolymphoma, pseudoepitheliomatous hyperplasia, or scleroderma/morphea-like changes. This article reviews tattoo complications, including their clinical and histopathological characteristics. METHODS: An open search was conducted on PubMed using the terms "tattoo", "complications", and "skin". No limits were set for period, language, or publication type of the articles. RESULTS: Reactions to tattoos are reported in up to 67% of people who get tattooed, with papulonodular and granulomatous reactions being the most common. Some neoplastic complications have been described, but their causality is still debated. Any pigment can cause adverse reactions, although red ink is more frequently associated with them. Patients with pre-existing dermatoses may experience exacerbation or complications of their diseases when getting tattoos; therefore, this procedure is not recommended for this patient group. CONCLUSIONS: Dermatological consultation is recommended before getting a tattoo, as well as a histopathological examination in case of complications. In patients who develop cutaneous inflammatory reactions following tattooing, additional studies are recommended to investigate systemic diseases such as sarcoidosis, pyoderma gangrenosum, atopic dermatitis, and neoplasms. It is important for physicians to be trained in providing appropriate care in case of complications.


Assuntos
Dermatopatias , Tatuagem , Tatuagem/efeitos adversos , Humanos , Dermatopatias/patologia , Dermatopatias/etiologia , Corantes/efeitos adversos , Fatores de Risco , Pele/patologia
12.
Proc Biol Sci ; 279(1726): 194-201, 2012 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21632626

RESUMO

Many biodiversity hotspots are located in montane regions, especially in the tropics. A possible explanation for this pattern is that the narrow thermal tolerances of tropical species and greater climatic stratification of tropical mountains create more opportunities for climate-associated parapatric or allopatric speciation in the tropics relative to the temperate zone. However, it is unclear whether a general relationship exists among latitude, climatic zonation and the ecology of speciation. Recent taxon-specific studies obtained different results regarding the role of climate in speciation in tropical versus temperate areas. Here, we quantify overlap in the climatic distributions of 93 pairs of sister species of mammals, birds, amphibians and reptiles restricted to either the New World tropics or to the Northern temperate zone. We show that elevational ranges of tropical- and temperate-zone species do not differ from one another, yet the temperature range experienced by species in the temperate zone is greater than for those in the tropics. Moreover, tropical sister species tend to exhibit greater similarity in their climatic distributions than temperate sister species. This pattern suggests that evolutionary conservatism in the thermal niches of tropical taxa, coupled with the greater thermal zonation of tropical mountains, may result in increased opportunities for allopatric isolation, speciation and the accumulation of species in tropical montane regions. Our study exemplifies the power of combining phylogenetic and spatial datasets of global climatic variation to explore evolutionary (rather than purely ecological) explanations for the high biodiversity of tropical montane regions.


Assuntos
Altitude , Clima , Especiação Genética , Vertebrados/classificação , Animais , Biodiversidade , Evolução Biológica , Geografia , América Latina , América do Norte , Filogenia , Vertebrados/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-33989119

RESUMO

This study estimates for the first time dietary acrylamide intake in Chile and conducts exposure risk assessments using the margin of exposure (MOE) method. A consumption frequency survey of starchy foods was carried out in the metropolitan region of Santiago, Chile on people from different socioeconomic levels aged between 12 and 65 years old. The acrylamide contents of the most frequently consumed foods were determined by an in-house validated GC-MS technique. The potatoes and bread group contributed ~77% to the dietary acrylamide exposure in Chile, with estimated daily mean exposure of 0.55 µg kgbw-1 day-1 and 0.22 µg kgbw-1 day-1, respectively. Chilean population aged between 12 and 17 years old presented the highest acrylamide intake (mean, 1.27 µg kgbw-1 day-1; 95th percentile, 3.90 µg kgbw-1 day-1). Finally, since the estimated MOEs were lower than 10,000, the dietary acrylamide exposure in the metropolitan region of Santiago, Chile is of public health concern according to the EFSA criteria.


Assuntos
Acrilamida/análise , Exposição Dietética/análise , Contaminação de Alimentos/análise , Acrilamida/administração & dosagem , Adolescente , Adulto , Idoso , Criança , Chile , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Pública , Medição de Risco , Adulto Jovem
14.
Viruses ; 13(7)2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372534

RESUMO

(1) Background: Hemorrhagic diseases in white-tailed deer (Odocoileus virginianus) are caused by orbiviruses and have significant economic impact on the deer ranching industry in the United States. Culicoides stellifer is a suspected vector of epizootic hemorrhagic disease virus (EHDV), with recent field evidence from Florida, but its natural history is poorly understood. Studying the distribution and abundance of C. stellifer across the landscape can inform our knowledge of how virus transmission can occur locally. We may then target vector management strategies in areas where viral transmission can occur. (2) Methods: Here, we used an occupancy modeling approach to estimate abundance of adult C. stellifer females at various physiological states to determine habitat preferences. We then mapped midge abundance during the orbiviral disease transmission period (May-October) in Florida. (3) Results: We found that overall, midge abundance was positively associated with sites in closer proximity to large-animal feeders. Additionally, midges generally preferred mixed bottomland hardwood and agricultural/sand/water habitats. Female C. stellifer with different physiological states preferred different habitats. (4) Conclusions: The differences in habitat preferences between midges across states indicate that disease risk for deer is heterogeneous across this landscape. This can inform how effective vector management strategies should be implemented.


Assuntos
Ceratopogonidae/patogenicidade , Ceratopogonidae/virologia , Infecções por Reoviridae/prevenção & controle , Animais , Ceratopogonidae/metabolismo , Cervos/virologia , Suscetibilidade a Doenças , Ecossistema , Florida , Vírus da Doença Hemorrágica Epizoótica/patogenicidade , Insetos Vetores/virologia , Modelos Teóricos , Orbivirus/metabolismo , Orbivirus/patogenicidade , Infecções por Reoviridae/veterinária , Doenças Transmitidas por Vetores/prevenção & controle
15.
J Anim Ecol ; 79(6): 1181-92, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20642767

RESUMO

1. Methods that assess patterns of phylogenetic relatedness, as well as character distribution and evolution, allow one to infer the ecological processes involved in community assembly. Assuming niche conservatism, assemblages should shift from phylogenetic clustering to evenness with decreasing geographic scale because the relative importance of mechanisms that shape assemblages is hypothesized to be scale-dependent. Whereas habitat filtering is more likely to act at regional scales because of increased habitat heterogeneity that allows sorting of ecologically similar species in contrasting environments, competition is more likely to act at local scales because low habitat heterogeneity provides few opportunities for niche partitioning. 2. We used species lists to assess assemblage composition, data on ecologically-relevant traits, and a molecular phylogeny, to examine the phylogenetic structure of antbird (Thamnophilidae) assemblages at three different geographical scales: regional (ecoregions), intermediate (100-ha plots) and local (mixed-flocks). In addition, we used patterns of phylogenetic beta diversity and beta diversity to separate the factors that structure antbird assemblages at regional scales. 3. Contrary to previous findings, we found a shift from phylogenetic evenness to clustering with decreasing geographical scale. We argue that this does not reject the hypothesis that habitat filtering is the predominant force in regional community assembly, because analyses of trait evolution and structure indicated a lack of niche conservatism in antbirds. 4. In some cases, phylogenetic evenness at regional scales can be an effect of historical biogeographic processes instead of niche-based processes. However, regional patterns of beta diversity and phylogenetic beta diversity suggested that phylogenetic structure in our study cannot be explained by the history of speciation and dispersal of antbirds, further supporting the habitat-filtering hypothesis. 5. Our analyses suggested that competitive interactions might not play an important role locally, which would provide a plausible explanation for the high alpha diversity of antbirds in Amazonia. 6. Finally, we emphasize the importance of including trait information in studies of phylogenetic community structure to adequately assess the mechanisms that determine species co-existence.


Assuntos
Aves/genética , Aves/fisiologia , Ecossistema , Filogenia , Animais , Comportamento Alimentar
16.
PeerJ ; 8: e8968, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440371

RESUMO

Variable contribution estimation for, and determination of variable importance within, ecological niche models (ENMs) remain an important area of research with continuing challenges. Most ENM algorithms provide normally exhaustive searches through variable space; however, selecting variables to include in models is a first challenge. The estimation of the explanatory power of variables and the selection of the most appropriate variable set within models can be a second challenge. Although some ENMs incorporate the variable selection rubric inside the algorithms, there is no integrated rubric to evaluate the variable importance in the Genetic Algorithm for Ruleset Production (GARP). Here, we designed a novel variable selection methodology based on the rulesets generated from a GARP experiment. The importance of the variables in a GARP experiment can be estimated based on the consideration of the prevalence of each environmental variable in the dominant presence rules of the best subset of models and its coverage. We tested the performance of this variable selection method based on simulated species with both weak and strong responses to simulated environmental covariates. The variable selection method generally performed well during the simulations with over 2/3 of the trials correctly identifying most covariates. We then predict the distribution of Toxostoma rufum (a bird with a cosmopolitan distribution) in the continental United States (US) and apply our variable selection procedure as a real-world example. We found that the distribution of T. rufum could be accurately modeled with 13 or 10 of 21 variables, using an UI cutoff of 0.5 or 0.25, respectively, arriving at parsimonious environmental coverages with good model accuracy. We also provide tools to simulate species distributions for testing ENM approaches using R.

17.
Ecol Evol ; 10(23): 12801-12816, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33304495

RESUMO

Diversification rates and evolutionary trajectories are known to be influenced by phenotypic traits and the geographic history of the landscapes that organisms inhabit. One of the most conspicuous traits in butterflies is their wing color pattern, which has been shown to be important in speciation. The evolution of many taxa in the Neotropics has also been influenced by major geological events. Using a dated, species-level molecular phylogenetic hypothesis for Preponini, a colorful Neotropical butterfly tribe, we evaluated whether diversification rates were constant or varied through time, and how they were influenced by color pattern evolution and biogeographical events. We found that Preponini originated approximately 28 million years ago and that diversification has increased through time consistent with major periods of Andean uplift. Even though some clades show evolutionarily rapid transitions in coloration, contrary to our expectations, these shifts were not correlated with shifts in diversification. Involvement in mimicry with other butterfly groups might explain the rapid changes in dorsal color patterns in this tribe, but such changes have not increased species diversification in this group. However, we found evidence for an influence of major Miocene and Pliocene geological events on the tribe's evolution. Preponini apparently originated within South America, and range evolution has since been dynamic, congruent with Andean geologic activity, closure of the Panama Isthmus, and Miocene climate variability.

18.
Cien Saude Colet ; 24(5): 1669-1678, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31166502

RESUMO

Bisexuality is the sexual, romantic, emotional and physical attraction that a person experiments for both of the biological sexes (men and women). Since the Venezuelan society is built under a heteronormative paradigm sometimes is considered that those sexualities, that drift apart from the social reality, are not comprehended thus generating a reject. Therefore, we conducted a study that was titled "Construction of Bisexual Identity in Venezuelan Adults: 'It is Not a transition, I Just Simply Am Like That'" that had as a general objective the understanding of the bisexual identity in Venezuelan adults. This article contemplates one dimension of this major project degree. In-depths interviews were carried out to willing participants and the obtained data were analyzed with the constant comparative method following an emerging design. Among the results four major categories were described, however, in this article we will be only focusing on the development of the bisexual identity.


Assuntos
Bissexualidade/psicologia , Minorias Sexuais e de Gênero/psicologia , Adulto , Feminino , Humanos , Entrevistas como Assunto , Masculino , Venezuela , Adulto Jovem
19.
J Wildl Dis ; 55(2): 304-315, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30277828

RESUMO

Brucellosis, caused by bacteria in the genus Brucella, is an infectious zoonosis affecting animals and humans worldwide. Free-ranging Rocky Mountain elk ( Cervus canadensis nelsoni) and bison ( Bison bison) in the Greater Yellowstone Ecosystem (areas of southwestern Montana, eastern Idaho, and northwestern Wyoming, US) are the self-sustaining reservoirs of bovine brucellosis ( Brucella abortus) and elk are considered the primary source of livestock infections. It has been hypothesized that Brucella-exposed elk might have different physiologic status (pregnancy rates and body condition) and migration behaviors than would healthy elk. Here we tested the effects of brucellosis serologic status on pregnancy rates and winter ingesta free body fat of 100 female elk in southwestern Montana. We also evaluated the effects of serologic status on two characteristics of spring migration behavior, migration types (migrant, mixed migrant, resident, disperser, nomad, and undetermined type) and timing (start and end dates and duration). The migration behaviors were quantified using a model-driven approach based on the relative net squared displacement. We detected a significant difference (P=0.003) in pregnancy rates between seropositive and seronegative elk, with about a 30% drop in seropositive individuals. However, we did not detect differences in body fat between seropositive and seronegative elk or differences in either migration type or timing of spring migration. These results confirmed that the major effect of brucellosis in free-ranging elk is associated with reproduction.


Assuntos
Migração Animal , Brucelose/veterinária , Cervos/microbiologia , Animais , Anticorpos Antibacterianos/sangue , Brucella abortus , Brucelose/epidemiologia , Brucelose/microbiologia , Feminino , Montana/epidemiologia , Estudos Soroepidemiológicos
20.
Ecol Evol ; 9(24): 13902-13918, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31938490

RESUMO

Despite the enormous advances in genetics, links between phenotypes and genotypes have been made for only a few nonmodel organisms. However, such links can be essential to understand mechanisms of ecological speciation. The Costa Rican endemic Mangrove Warbler subspecies provides an excellent subject to study differentiation with gene flow, as it is distributed along a strong precipitation gradient on the Pacific coast with no strong geographic barriers to isolate populations. Mangrove Warbler populations could be subject to divergent selection driven by precipitation, which influences soil salinity levels, which in turn influences forest structure and food resources. We used single nucleotide polymorphisms (SNPs) and morphological traits to examine the balance between neutral genetic and phenotypic divergence to determine whether selection has acted on traits and genes with functions related to specific environmental variables. We present evidence showing: (a) associations between environmental variables and SNPs, identifying candidate genes related to bill morphology (BMP) and osmoregulation, (b) absence of population genetic structure in neutrally evolving markers, (c) divergence in bill size across the precipitation gradient, and (d) strong phenotypic differentiation (P ST) which largely exceeds neutral genetic differentiation (F ST) in bill size. Our results indicate an important role for salinity, forest structure, and resource availability in maintaining phenotypic divergence of Mangrove Warblers through natural selection. Our findings add to the growing body of literature identifying the processes involved in phenotypic differentiation along environmental gradients in the face of gene flow.

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