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1.
Sci Rep ; 14(1): 13966, 2024 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886412

RESUMEN

Foot-propelled diving comprises the primary locomotion-based feeding strategy for many birds, including families such as Phalacrocoracidae, Anhingidae, Podicipedidae, Gaviidae, and the diving ducks within Anatidae. While the morphology of specialized divers is well known, the corresponding morphology is less known for birds not as specialized but capable of diving, such as the coots (Rallidae, Fulica spp.). To compare the osteology of Fulica with other (non-diving) Rallidae, and with foot-propelled diving birds that are distantly related, we considered osteological characters, as well as the proportion of the hind limb bones and the femoral splay angle to construct a phylomorphospace, and to perform a comparative disparity analysis considering ecomorphologically relevant characters related to swimming and diving. Coots resulted to be significantly disparate from other Rallidae showing many traits of specialized foot-propelled divers, but only noticeable when compared with other rallids, as the degree of development of these traits is markedly less than in loons, grebes, or cormorants. This may correspond to a stabilizing selection of characteristics associated with a generalist morphology in Fulica. Studying adaptation in generalist taxa broadens our understanding of ecomorphologically significant features, thereby enabling us to generalize their evolutionary patterns.


Asunto(s)
Aves , Buceo , Animales , Buceo/fisiología , Aves/anatomía & histología , Aves/fisiología , Filogenia , Evolución Biológica , Locomoción/fisiología
2.
Ecol Lett ; 27(1): e14351, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38111128

RESUMEN

Dominance of neotropical tree communities by a few species is widely documented, but dominant trees show a variety of distributional patterns still poorly understood. Here, we used 503 forest inventory plots (93,719 individuals ≥2.5 cm diameter, 2609 species) to explore the relationships between local abundance, regional frequency and spatial aggregation of dominant species in four main habitat types in western Amazonia. Although the abundance-occupancy relationship is positive for the full dataset, we found that among dominant Amazonian tree species, there is a strong negative relationship between local abundance and regional frequency and/or spatial aggregation across habitat types. Our findings suggest an ecological trade-off whereby dominant species can be locally abundant (local dominants) or regionally widespread (widespread dominants), but rarely both (oligarchs). Given the importance of dominant species as drivers of diversity and ecosystem functioning, unravelling different dominance patterns is a research priority to direct conservation efforts in Amazonian forests.


Asunto(s)
Ecosistema , Bosques , Humanos , Árboles , Brasil , Biodiversidad
3.
Plants (Basel) ; 12(14)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37514225

RESUMEN

Macroevolutionary patterns in the association between plant species and their herbivores result from ecological divergence promoted by, among other factors, plants' defenses and nutritional quality, and herbivore adaptations. Here, we assessed the performance of the herbivores Lema trilineata daturaphila, a trophic specialist on Datura, and Spodoptera frugiperda, a polyphagous pest herbivore, when fed with species of Datura. We used comparative phylogenetics and multivariate methods to examine the effects of Datura species' tropane alkaloids, leaf trichomes, and plant macronutrients on the two herbivores´ performances (amount of food consumed, number of damaged leaves, larval biomass increment, and larval growth efficiency). The results indicate that species of Datura do vary in their general suitability as food host for the two herbivores. Overall, the specialist performs better than the generalist herbivore across Datura species, and performance of both herbivores is associated with suites of plant defenses and nutrient characteristics. Leaf trichomes and major alkaloids of the Datura species are strongly related to herbivores' food consumption and biomass increase. Although hyoscyamine better predicts the key components of the performance of the specialist herbivore, scopolamine better predicts the performance of the generalist; however, only leaf trichomes are implicated in most performance components of the two herbivores. Nutrient quality more widely predicts the performance of the generalist herbivore. The contrasting effects of plant traits and the performances of herbivores could be related to adaptive differences to cope with plant toxins and achieve nutrient balance and evolutionary trade-offs and synergisms between plant traits to deal with a diverse community of herbivores.

4.
Environ Entomol ; 52(3): 341-349, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37043621

RESUMEN

Ecosystem loss and degradation has become a worldwide concern. The implementation of ecological restoration plans has been proposed to facilitate the recovery of ecosystems. It is imperative that once restoration strategies have been implemented, the effects of these actions in the medium and long term be evaluated, particularly the structure and functioning of the ecosystem. Diversity (α- and ß-diversity) of beetles attracted to dung was assessed and compared in 3 habitat conditions (conserved forest, passive restoration, and active restoration) at 2 different seasons during the year (dry vs. rainy season) in cloud forest in San Luis Potosí (central Mexico). We found that the dry season was slightly richer than the rainy season, but the latter was significantly more diverse. Species diversity and composition in active restoration were more similar to passive restoration, and both differed greatly from the conserved forest. In contrast, conserved and passive restoration conditions exhibited similar patterns in ß-diversity of insects likely because they maintain more species associated with the original vegetation of the cloud forest. Beetle assemblages could be of more habitat generalists, as they actively distribute across the restoration sites. Beetles attracted to dung provide an overview of the effect of restoration in early faunal recovery, even though we monitored this entomofauna for a short period (31 months after the restoration plots were established). These beetles can be a useful indicator for exploring the main forces driving species diversity for the management and conservation status of cloud forests, a threatened ecosystem.


Asunto(s)
Escarabajos , Ecosistema , Animales , Biodiversidad , Bosques , Estaciones del Año
5.
Parasitology ; : 1-11, 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36748352

RESUMEN

Polymorphidae is a monophyletic group of acanthocephalans distributed worldwide. Within this family, Hexaglandula corynosoma is a specialist species that uses a single bird species as a definitive host. Southwellina hispida is a generalist species that uses a broad spectrum of definitive hosts to complete its life cycle. In the current research, sequences of cytochrome c oxidase subunit 1 (cox1) from mitochondrial DNA were generated from 44 specimens of H. corynosoma and 76 of S. hispida distributed sympatrically in 6 biogeographic provinces of Mexico with the objective of characterizing and comparing the population genetic structure of 2 acanthocephalan species with opposing life strategies. The phylogeographic studies indicated that the populations of both species lacked a phylogeographic structure and exhibited high haplotype diversity, low nucleotide diversity and low Fst values among the biogeographic provinces; in combination with negative values on the neutrality test, this suggests that the populations of acanthocephalans are expanding. Paratenic hosts are key for the transmission from intermediate to definitive hosts in the generalist species. However, the inclusion of paratenic hosts does not play a principal role in the population genetic structure of S. hispida within its distribution along the coasts of Mexico.

6.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36430785

RESUMEN

Molecular phenotypes induced by environmental stimuli can be transmitted to offspring through epigenetic inheritance. Using transcriptome profiling, we show that the adaptation of Helicoverpa armigera larvae to soybean peptidase inhibitors (SPIs) is associated with large-scale gene expression changes including the upregulation of genes encoding serine peptidases in the digestive system. Furthermore, approximately 60% of the gene expression changes induced by SPIs persisted in the next generation of larvae fed on SPI-free diets including genes encoding regulatory, oxidoreductase, and protease functions. To investigate the role of epigenetic mechanisms in regulating SPI adaptation, the methylome of the digestive system of first-generation larvae (fed on a diet with and without SPIs) and of the progeny of larvae exposed to SPIs were characterized. A comparative analysis between RNA-seq and Methyl-seq data did not show a direct relationship between differentially methylated and differentially expressed genes, while trypsin and chymotrypsin genes were unmethylated in all treatments. Rather, DNA methylation potential epialleles were associated with transcriptional and translational controls; these may play a regulatory role in the adaptation of H. armigera to SPIs. Altogether, our findings provided insight into the mechanisms of insect adaptation to plant antiherbivore defense proteins and illustrated how large-scale transcriptional reprograming of insect genes can be transmitted across generations.


Asunto(s)
Glycine max , Mariposas Nocturnas , Animales , Glycine max/genética , Glycine max/metabolismo , Inhibidores de Proteasas/farmacología , Regulación hacia Arriba , Serina Proteasas/metabolismo , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismo , Quimotripsina/genética , Quimotripsina/metabolismo , Tripsina/metabolismo , Larva/genética , Larva/metabolismo , Serina/metabolismo
7.
BMC Ecol Evol ; 22(1): 74, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35672668

RESUMEN

BACKGROUND: Diet is a key component of a species ecological niche and plays critical roles in guiding the trajectories of evolutionary change. Previous studies suggest that dietary evolution can influence the rates and patterns of species diversification, with omnivorous (animal and plant, 'generalist') diets slowing down diversification compared to more restricted ('specialist') herbivorous and carnivorous diets. This hypothesis, here termed the "dietary macroevolutionary sink" hypothesis (DMS), predicts that transitions to omnivorous diets occur at higher rates than into any specialist diet, and omnivores are expected to have the lowest diversification rates, causing an evolutionary sink into a single type of diet. However, evidence for the DMS hypothesis remains conflicting. Here, we present the first test of the DMS hypothesis in a lineage of ectothermic tetrapods-the prolific Liolaemidae lizard radiation from South America. RESULTS: Ancestral reconstructions suggest that the stem ancestor was probably insectivorous. The best supported trait model is a diet-dependent speciation rate, with independent extinction rates. Herbivory has the highest net diversification rate, omnivory ranks second, and insectivory has the lowest. The extinction rate is the same for all three diet types and is much lower than the speciation rates. The highest transition rate was from omnivory to insectivory, and the lowest transition rates were between insectivory and herbivory. CONCLUSIONS: Our findings challenge the core prediction of the DMS hypothesis that generalist diets represent an 'evolutionary sink'. Interestingly, liolaemid lizards have rapidly and successfully proliferated across some of the world's coldest climates (at high elevations and latitudes), where species have evolved mixed arthropod-plant (omnivore) or predominantly herbivore diets. This longstanding observation is consistent with the higher net diversification rates found in both herbivory and omnivory. Collectively, just like the evolution of viviparity has been regarded as a 'key adaptation' during the liolaemid radiation across cold climates, our findings suggest that transitions from insectivory to herbivory (bridged by omnivory) are likely to have played a role as an additional key adaptation underlying the exceptional diversification of these reptiles across extreme climates.


Asunto(s)
Lagartos , Animales , Dieta/veterinaria , Ecosistema , Herbivoria , Filogenia
8.
Bull Entomol Res ; 112(4): 528-535, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35256021

RESUMEN

The performance (development and reproduction) of generalist predators can vary greatly among the prey species that they use, and these differences can influence the ability of predatory insects to suppress pest populations. The aim of this study was to compare the performance of larvae of the green lacewing Chrysoperla rufilabris (Burmeister, 1839) by offering 16 species of aphids and by assessing the effects of each species on the survival, larval development time, prey consumption, pupal mass and egg load of adult Chr. rufilabris females taking aphid phylogeny into account. Chrysoperla rufilabris larvae preyed on individuals from all 16 aphid species, but complete development, adult emergence and egg load production were achieved only in seven species. As a general pattern, the best levels of performance were achieved for an aphid clade that includes the soybean aphid, Aphis glycines (Matsumara, 1917), and for a milkweed-feeding species, Myzocallis asclepiadis (Monell, 1879). We found significant phylogenetic clustering for most of the performance traits indicating the aspects of specialization in the diet breadth of Chr. rufilabris despite the fact that this species is considered a generalist aphid predator. These findings can help us to understand the interactions of this species in agroecological food webs, where it is commonly found, and provide insights into why natural, conservation biological control or augmentative releases may succeed or fail.


Asunto(s)
Áfidos , Animales , Dieta , Femenino , Insectos , Larva , Control Biológico de Vectores , Filogenia , Conducta Predatoria
9.
Gigascience ; 112022 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-35333301

RESUMEN

BACKGROUND: A central challenge of DNA gut content analysis is to identify prey in a highly degraded DNA community. In this study, we evaluated prey detection using metabarcoding and a method of mapping unassembled shotgun reads (Lazaro). RESULTS: In a mock prey community, metabarcoding did not detect any prey, probably owing to primer choice and/or preferential predator DNA amplification, while Lazaro detected prey with accuracy 43-71%. Gut content analysis of field-collected arthropod epigeal predators (3 ants, 1 dermapteran, and 1 carabid) from agricultural habitats in Brazil (27 samples, 46-273 individuals per sample) revealed that 64% of the prey species detections by either method were not confirmed by melting curve analysis and 87% of the true prey were detected in common. We hypothesized that Lazaro would detect fewer true- and false-positive and more false-negative prey with greater taxonomic resolution than metabarcoding but found that the methods were similar in sensitivity, specificity, false discovery rate, false omission rate, and accuracy. There was a positive correlation between the relative prey DNA concentration in the samples and the number of prey reads detected by Lazaro, while this was inconsistent for metabarcoding. CONCLUSIONS: Metabarcoding and Lazaro had similar, but partially complementary, detection of prey in arthropod predator guts. However, while Lazaro was almost 2× more expensive, the number of reads was related to the amount of prey DNA, suggesting that Lazaro may provide quantitative prey information while metabarcoding did not.


Asunto(s)
Artrópodos , Animales , Artrópodos/genética , Artrópodos/metabolismo , Brasil , ADN/metabolismo , Ecosistema , Humanos , Análisis de Secuencia de ADN
10.
Curr Zool ; 68(1): 27-40, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35169627

RESUMEN

Characterizing the diversity and structure of host-parasite communities is crucial to understanding their eco-evolutionary dynamics. Malaria and related haemosporidian parasites are responsible for fitness loss and mortality in bird species worldwide. However, despite exhibiting the greatest ornithological biodiversity, avian haemosporidians from Neotropical regions are quite unexplored. Here, we analyze the genetic diversity of bird haemosporidian parasites (Plasmodium and Haemoproteus) in 1,336 individuals belonging to 206 bird species to explore for differences in diversity of parasite lineages and bird species across 5 well-differentiated Peruvian ecoregions. We detected 70 different haemosporidian lineages infecting 74 bird species. We showed that 25 out of the 70 haplotypes had not been previously recorded. Moreover, we also identified 81 new host-parasite interactions representing new host records for these haemosporidian parasites. Our outcomes revealed that the effective diversity (as well as the richness, abundance, and Shannon-Weaver index) for both birds and parasite lineages was higher in Amazon basin ecoregions. Furthermore, we also showed that ecoregions with greater diversity of bird species also had high parasite richness, hence suggesting that host community is crucial in explaining parasite richness. Generalist parasites were found in ecoregions with lower bird diversity, implying that the abundance and richness of hosts may shape the exploitation strategy followed by haemosporidian parasites. These outcomes reveal that Neotropical region is a major reservoir of unidentified haemosporidian lineages. Further studies analyzing host distribution and specificity of these parasites in the tropics will provide important knowledge about phylogenetic relationships, phylogeography, and patterns of evolution and distribution of haemosporidian parasites.

11.
Fractal rev. psicol ; 34: e5887, 2022.
Artículo en Portugués | LILACS, Index Psicología - Revistas | ID: biblio-1384964

RESUMEN

A formação em Psicologia é alvo de discussões desde a sua regulamentação como profissão. O presente estudo teve como objetivo identificar a percepção dos egressos de um curso de graduação em Psicologia, numa universidade federal nordestina, acerca da formação generalista, considerando a sua história "recente" junto à expansão universitária no Brasil e a conformidade com as Diretrizes Curriculares Nacionais. Trata-se de uma pesquisa qualitativa, cujos dados foram obtidos por meio de entrevistas semiestruturadas individuais, com oito psicólogos egressos, atuantes no mercado de trabalho. A análise dos resultados ocorreu com base na Análise de Conteúdo de Bardin (1977), pela qual se observou uma compreensão pouco assertiva quanto ao conceito de formação generalista e certa dificuldade em nomear-se um profissional como generalista, ainda que essa postura faça parte da prática diária. Além disso, percebeu-se a existência de críticas referentes à matriz curricular e ao relacionamento com os docentes. No entanto, sobressai uma avaliação positiva.(AU)


The formation in Psychology has been the subject of discussions since its regulation as a profession. The present study aimed to identify the perception of graduates of a Psychology undergraduate course at a federal university in the northeast, about the generalist formation, considering your "recent" history with the university expansion in Brazil and the compliance with the National Curricular Guidelines. This is a qualitative study, whose data were obtained through individual semi-structured interviews, with eight graduates psychologists inserted in the labor market. The analysis of the results occurred based on Bardin's Content Analysis (1977), where it was observed a little assertive understanding about the concept of generalist formation, and a certain difficulty in naming itself as a generalist professional, even though this posture is part of daily practice. Besides that, there were criticisms about the curriculum and the relationship with the teachers. However, a positive evaluation stands out.(AU)


Desde su regulación como profesión, la Psicología ha sido objeto de discusiones. El presente estudio tuvo como objetivo identificar la percepción de los egresados de un curso de graduación en Psicología de una universidad federal de la región del nordeste, sobre la formación general, considerando su historia "reciente" así como la expansión universitaria en Brasil y el cumplimiento de la Orientaciones Curriculares Nacionales (DCN). Se trata de una investigación cualitativa, cuyos datos se obtuvieron a través de entrevistas individuales semi-estructuradas realizadas a ocho (8) graduados en Psicología y activos en el mercado laboral. El análisis de los resultados se basó en el Content Analysis de Bardin (1977), donde se constató una comprensión menos asertiva del concepto de formación general y cierta dificultad para reconocerse como profesional generalista a pesar que esta postura forma parte de la práctica diaria. Además se observaron ciertas críticas con respecto a la matriz curricular y a la relación con los profesores. Sin embargo, lo que se destaca es una crítica positiva.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Psicología/educación , Enseñanza , Curriculum
12.
Bol. Inst. Pesca (Impr.) ; 48: e728, 2022. mapas, graf, tab
Artículo en Inglés | VETINDEX | ID: biblio-1417193

RESUMEN

The main objective of this study was to identify spatial and seasonal variations on the diet of Psalido-don aff. fasciatus from the Tibagi River (South Brazil) before the construction of the Tibagi Montante hydropower plant. Fish were collected quarterly between October 2017 and July 2019. 536 stomachs containing feeding items and identified to the lowest taxonomic level as possible have been analyzed. Results showed that plants, Hymenoptera, and insect parts in general were the most consumed items. The analysis of feeding strategy showed a diet based on rare items but with individuals varying among specialist, generalist, and opportunistic trends depending on the season. The non-metric multidimen-sional scaling (NMDS) revealed diet overlap in both spatial and seasonal terms, which was confir-med by the permutational analysis of variance (PERMANOVA). The indicator value analysis (IndVal) identified 15 items as the most important components of this species' diet such as superior plants, Hymenoptera and insect parts. Therefore, before the formation of the reservoir, P. aff. fasiatus could be characterized as predominantly herbivore with a strong trend for insectivory. Across seasons, this species had a specialized diet all year, although with more specialized preferences in the spring when the consumption of plants was increased.(AU)


O objetivo deste trabalho foi identificar variações espaciais e sazonais da dieta do Psalidodon aff. fas-ciatus do rio Tibagi (Sul do Brasil) antes da construção da usina hidrelétrica Tibagi Montante. Os peixes foram amostrados trimestralmente entre outubro de 2017 e julho de 2019. Foram analisados 536 estômagos contendo itens alimentares e identificados até o menor nível taxonômico possível. Os resultados indicaram que vegetais, Hymenoptera e restos de insetos em geral foram os itens mais con-sumidos. A análise da estratégia alimentar mostrou uma dieta baseada em itens raros, mas com indi-víduos variando entre tendências especialistas, generalistas e oportunistas, dependendo da estação. O escalonamento multidimensional não-métrico (NMDS) mostrou sobreposição da composição da dieta tanto em escala espacial quanto sazonal, o que foi confirmado pela análise de variância permutacional (PERMANOVA). A análise do valor indicador (Indval) identificou 15 itens como os componentes mais importantes na dieta desta espécie, como plantas superiores, Hymenoptera e resto de insetos. Por-tanto, antes da formação do reservatório, P.aff. fasciatus, pode ser caracterizada como predominante-mente herbívora com forte tendência insetívora. Ao longo das estações, esta espécie apresentou dieta especializada durante todo o ano, embora com especialização na primavera, quando houve aumento do consumo de vegetais. (AU)


Asunto(s)
Animales , Reservorios de Agua , Characidae/fisiología , Brasil , Fenómenos Fisiológicos Nutricionales de los Animales
13.
Rev. biol. trop ; Rev. biol. trop;69(2)jun. 2021.
Artículo en Español | LILACS, SaludCR | ID: biblio-1387646

RESUMEN

Resumen Introducción: El café es una planta altamente micotrófica, por lo que la interacción con los hongos micorrízicos arbusculares (HMA) se ha estudiado en distintos países tropicales. La mayoría de los trabajos publicados indican que el café se beneficia de la asociación micorrízica, donde los HMA confieren protección ante patógenos y enfermedades, incrementa la absorción de agua, así como la adaptación de la planta durante el trasplante de vivero al campo. Objetivo: Se realizó una revisión donde se resumieron y analizaron trabajos reportados por la asociación de HMA y café de los últimos 10 años, enfocada en la distribución global de especies de HMA, beneficio nutricional de la asociación y su interacción con patógenos. Métodos: Se revisaron diferentes bases de datos que reportaron trabajos realizados en los principales países productores de café. La revisión se centró principalmente en los trabajos publicados entre el 2000 y el 2019, sin embargo, en algunos casos se incluyeron artículos clásicos en el tema, que no corresponden al periodo señalado, principalmente los realizados en Brasil desde 1986. Se organizó el número de especies reportadas por país, se buscaron sinonimias y agruparon por familia, género y especie. Los trabajos donde solo se reportan géneros o las especies presentaron ambigüedad, se usaron como referencia, pero no se incluyeron en el análisis final. Se resumieron los reportes de los beneficios de la interacción de HMA con café, así como la tolerancia a patógenos. Resultados: Los datos recabados muestran que hay más de 100 especies de HMA asociadas con el café, lo cual representa más de la tercera parte del total de las especies reportadas en el mundo. En Colombia se reportó la mayor riqueza de especies de HMA, lo cual puede deberse a que es el país con más reportes en el tema. Conclusiones: Esta información muestra los beneficios de la incorporación de HMA en los programas de replantación de fincas de café, pues estos hongos son un elemento clave en la nutrición de los cafetos, sin embargo, se debe considerar la variedad de café cultivada y la introducción de HMA, pues no en todas hay una asociación exitosa.


Abstract Introduction: Coffee is a highly mycotrophic plant, its interaction with arbuscular mycorrhizal fungi has been studied among different tropical countries. The majority of the published works indicates that coffee is benefited from the mycorrhizal association, where the AMF confers protection against pathogens and diseases, increases water absorption, as well as it increases the adaptation of the plant at transplant from nurseries to the main plantation. Objective: A review was made where we summarized and analyze the research reports of AMF with coffee from at least the past 10 years, focused on AMF global species distribution, nutritional benefits of the association and interaction with pathogens. Methods: We retrieved available bibliographic data from coffee producer countries in public databases. We considered published works from 2000 to 2019, nevertheless, we included classic papers on the topic, outside that period, mainly the ones performed in Brazil since 1986. We organized the number of reported species per country, we look for synonyms, grouped them by family, genera and species. The reports that only reported genera or where ambiguous were used as reference but not considered for the final analysis. We summarized the reports of the benefits of the AMF interaction in coffee, as well as pathogen tolerance. Results: The collected data shows that there are more than 100 AMF species associated with coffee, which represents more than a third part of the total of reported species worldwide. We found that Colombia has the highest richness, but it also has the highest number of published reports. Conclusions: This information shows the benefits of the incorporation of AMF to coffee plantation programs, because these fungi are a key element in coffee plant nutrition, nevertheless, the coffee variety should be considered when introducing AMF, as not all associations has been efficient.


Asunto(s)
Café , Micorrizas , Hongos , México
14.
PeerJ ; 8: e8836, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32257647

RESUMEN

A generalist pollination system may be characterized through the interaction of a plant species with two or more functional groups of pollinators. The spatiotemporal variation of the most effective pollinator is the factor most frequently advocated to explain the emergence and maintenance of generalist pollination systems. There are few studies merging variation in floral visitor assemblages and the efficacy of pollination by different functional groups. Thus, there are gaps in our knowledge about the variation in time of pollinator efficacy and frequency of generalist species. In this study, we evaluated the pollination efficacy of the floral visitors of Edmundoa lindenii (Bromeliaceae) and their frequency of visits across four reproductive events. We analyzed the frequency of the three groups of floral visitors (large bees, small bees, and hummingbirds) through focal observations in the reproductive events of 2015, 2016, 2017, and 2018. We evaluated the pollination efficacy (fecundity after one visit) through selective exposure treatments and the breeding system by manual pollinations. We tested if the reproductive success after natural pollination varied between the reproductive events and also calculated the pollen limitation index. E. lindenii is a self-incompatible and parthenocarpic species, requiring the action of pollinators for sexual reproduction. Hummingbirds had higher efficacy than large bees and small bees acted only as pollen larcenists. The relative frequency of the groups of floral visitors varied between the reproductive events. Pollen limitation has occurred only in the reproductive event of 2017, when visits by hummingbirds were scarce and reproductive success after natural pollination was the lowest. We conclude that hummingbirds and large bees were the main and the secondary pollinators of E. lindenii, respectively, and that temporal variations in the pollinator assemblages had effects on its reproductive success. Despite their lower pollination efficacy, large bees ensured seed set when hummingbirds failed. Thus, we provide evidence that variable pollination environments may favor generalization, even under differential effectiveness of pollinator groups if secondary pollinators provide reproductive assurance.

15.
Front Public Health ; 8: 612531, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33614569

RESUMEN

Dramatic shifts are occurring in the size, shape and skill of rural health workforces in Pacific island countries (PICs) due to an unprecedented convergence of political agreement, policy commitment, donor support and technical assistance. In particular, the impact of "medical internationalism" is being felt across the Pacific region, with new doctors returning home in far greater numbers than ever before, the majority having graduated from medical schools in Cuba, China and other countries outside the region, in addition to the more typical numbers graduating and returning home from the region's main medical schools in Fiji and Papua New Guinea. With an agreed regional vision of "Healthy Islands" across the Pacific, the main objective of expanding overseas training opportunities for Pacific island medical students has been to correct the widespread centralization and maldistribution of the medical workforce in PICs and improve health access and quality of care in rural areas by deploying the new graduates to outer-island facilities. However, the return of these new graduates in several PICs has demonstrated that additional training is required to equip them with the knowledge and skills necessary to practice safely and sustainably in unsupervised settings. Thus, the development of specific postgraduate programmes has been urgently needed to provide pathways to vocational training and specialization in rural medicine appropriate to the Pacific region. Rocketship Pacific Ltd. (Rocketship) is an international health charity, based in Australia, dedicated to improving health in Pacific island countries through stronger primary care. Rocketship's particular focus to date has been on education and capacity-building for doctors and nurses working in rural communities and outer-island facilities. Since 2015, Rocketship has been working in partnership with the Ministries of Health and other key partners in Solomon Islands, Timor-Leste, Tonga and Vanuatu to design and deliver postgraduate training programmes in the core generalist disciplines family, community and rural hospital medicine. To date, this has resulted in new postgraduate Family Medicine courses being established in Timor-Leste and Tonga; a rural medical workforce support programme being delivered in Vanuatu; and a new Postgraduate Diploma in Rural Generalist Medicine being designed in Solomon Islands. These new programmes, as well as other notable initiatives elsewhere in the Pacific such as the Master of Medicine (Rural) programme in Papua New Guinea, the Diploma and Master of Family Medicine programme in Fiji and the Cook Islands Fellowship in General Practice, are transforming the health workforce in PICs with the potential to benefit island people across the "Blue Continent." This paper describes the establishment of new postgraduate training programmes in family, community and rural hospital medicine in Timor-Leste, Tonga, Solomon Islands and Vanuatu from the perspective of Rocketship, the non-profit organization engaged by each country's Ministry of Health (or equivalent) to provide expert technical assistance with their initiative.


Asunto(s)
Fuerza Laboral en Salud , Población Rural , Australia , China , Cuba , Fiji , Humanos , Melanesia , Islas del Pacífico , Papúa Nueva Guinea , Polinesia , Salud Rural , Timor Oriental , Tonga , Vanuatu , Recursos Humanos
16.
World J Microbiol Biotechnol ; 35(12): 182, 2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31728757

RESUMEN

Endophytes improve the host performance in areas of high plant endemicity. Paullinia cupana is an Amazonia plant species of economic and social importance due to the high caffeine concentration in its seeds. An interesting strategy to identify endophytic microorganisms with potential biotechnological application is to understand the factors that influence the endophytic community to rationalize the host management programs. We used the next-generation sequencing for bacterial 16S rRNA gene to examine how the P. cupana organ, genotype, and geographic location influenced its endophytic bacterial community. We obtained 1520 operational taxonomic units (OTUs) distributed in 19 phyla, 32 classes, 79 orders, 114 families and 174 genera. The P. cupana roots and leaves were specifically colonized by the bacterial genera Acidothermus and Porphyromonas, respectively, with high relative frequency. The plant organ type influenced the endophytic community's richness, diversity, OTUs composition, relative abundance of phyla and genera, and genera interaction network. However, the host plant genotype and geographic location influenced the composition and interaction among genera in the network analysis. Prevotella is a super-generalist genus in the interaction network of endophytic bacteria of P. cupana. This study revealed endophytic bacterial groups of importance to P. cupana and stressed that the host plant organ modulates the structure and interactions within this community. Our results indicated that the microbial community adapted to colonize P. cupana by adjusting to its composition and interaction network. The isolation of abundant and super-generalist bacterial genera shall help to examine their functionality to the composition and fitness of the endophytic community of P. cupana.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Ecología , Endófitos/clasificación , Endófitos/aislamiento & purificación , Paullinia/microbiología , Bacterias/genética , Brasil , ADN Bacteriano/aislamiento & purificación , Endófitos/genética , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Microbianas , Microbiota/genética , Filogenia , Hojas de la Planta/microbiología , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Semillas/microbiología
17.
Clin J Oncol Nurs ; 23(4): 387-394, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31322621

RESUMEN

BACKGROUND: Oncology nurse navigation opportunities are rapidly expanding as the value of the role is recognized. However, there is a lack of training opportunities focusing on the unique needs of the oncology nurse navigator (ONN). Most navigator training programs provide only general oncology navigation content. OBJECTIVES: The purpose of this article is to evaluate the current state of training for the novice ONN and begin to identify core elements to inform development of a standardized training program. METHODS: Navigator training programs and literature related to the role and development needs of the novice ONN were reviewed. FINDINGS: Training of the novice ONN varies widely, with little evaluation of the most effective way to prepare for the role. It is clear that the learning needs of the ONN are different than those of other types of navigators and oncology nurses.


Asunto(s)
Competencia Clínica , Capacitación en Servicio/organización & administración , Neoplasias/enfermería , Enfermería Oncológica , Curriculum , Humanos , Capacitación en Servicio/normas , Rol de la Enfermera
18.
Parasit Vectors ; 12(1): 274, 2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31138275

RESUMEN

BACKGROUND: Oil palm plantation establishment in Colombia has the potential to impact Chagas disease transmission by increasing the distribution range of Rhodnius prolixus. In fact, previous studies have reported Trypanosoma cruzi natural infection in R. prolixus captured in oil palms (Elaeis guineensis) in the Orinoco region, Colombia. The aim of this study is to understand T. cruzi infection in vectors in oil palm plantations relative to community composition and host dietary specialization by analyzing vector blood meals and comparing these results to vectors captured in a native palm tree species, Attalea butyracea. METHODS: Rhodnius prolixus nymphs (n = 316) were collected from A. butyracea and E. guineensis palms in Tauramena, Casanare, Colombia. Vector blood meals from these nymphs were determined by amplifying and sequencing a vertebrate-specific 12S rRNA gene fragment. RESULTS: Eighteen vertebrate species were identified and pigs (Sus scrofa) made up the highest proportion of blood meals in both habitats, followed by house mouse (Mus musculus) and opossum (Didelphis marsupialis). Individual bugs feeding only from generalist mammal species had the highest predicted vector infection rate, suggesting that generalist mammalian species are more competent hosts for T. cruzi infection . CONCLUSIONS: Oil palm plantations and A. butyracea palms found in altered areas provide a similar quality habitat for R. prolixus populations in terms of blood meal availability. Both habitats showed similarities in vector infection rate and potential host species, representing a single T. cruzi transmission scenario at the introduced oil palm plantation and native Attalea palm interface.


Asunto(s)
Agricultura , Enfermedad de Chagas/transmisión , Insectos Vectores/parasitología , Rhodnius/fisiología , Árboles , Trypanosoma cruzi/aislamiento & purificación , Animales , Sangre , Colombia , Didelphis , Ecosistema , Especificidad del Huésped , Insectos Vectores/fisiología , Ratones , Aceite de Palma , Rhodnius/parasitología , Porcinos
19.
Pest Manag Sci ; 75(7): 1986-1992, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30610750

RESUMEN

BACKGROUND: A wide range of supplementary food resources can be offered to generalist predatory mites to improve their survival and reproduction and enhance their persistence in the environment. We investigated the relative suitability of different pollen types for the survival and reproduction of Neoseiulus californicus and its life history on a mixed diet of pollen and prey. We also evaluated the population dynamics of Tetranychus urticae in the presence of N. californicus with or without pollen, and in comparison to Phytoseiulus macropilis. RESULTS: Survival and reproduction of N. californicus adults were satisfactory on exclusive diets of T. urticae, cattail pollen, palm pollen and bee pollen. However, mites did not reproduce when fed only pollen during both immature and adult stages. Both predatory mites successfully controlled T. urticae. Although the specialist P. macropilis was more efficient in suppressing the pest population in the short term, it abandoned plants at low prey densities, whereas N. californicus performed better and persisted longer under prey scarcity. CONCLUSION: N. californicus is an efficient biological control agent of T. urticae and the provision of supplementary food could retain them in the crop prior to the arrival of the pest or in periods of prey scarcity. © 2019 Society of Chemical Industry.


Asunto(s)
Ácaros/fisiología , Control Biológico de Vectores/métodos , Conducta Predatoria , Tetranychidae , Animales , Arecaceae , Dieta/veterinaria , Fragaria , Ácaros/crecimiento & desarrollo , Polen , Reproducción/fisiología , Typhaceae
20.
Acta sci., Biol. sci ; Acta sci., Biol. sci;41: e47720, 20190000. map, tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1460897

RESUMEN

The reproductive process promotes morphophysiological and behavioral changes in fish species throughout their life cycle. Its success is vital to define their resilience in the environment. This study aimed to evaluate the reproductive biology of the endemic fish species Astyanax bifasciatusin a tributary of the Lower Iguaçu River Basin, Paraná, Brazil. Fish were collected monthly at four sites along the Jirau Alto River in the city of Dois Vizinhos from October 2015 to September 2016. A standardized catch effort with gill nets and fish traps was used. In the laboratory, standard length and total weight were recorded. After anesthesia, the animals were sectioned to macroscopically determine the sex, sexual maturity stage, and presence of celomatic fat. The gonads and liver were removed to determine the gonadosomatic and hepatosomatic indexes, respectively. A total of 160 individuals (104 femalesand 56 males) were used. The gonadosomatic index, frequency of the gonadal maturation stages, and condition factor showed a long reproductive period with two investment cycles for both sex. Length at first sexual maturity was 4.57 cm for females and 3.56 cm for males. The reproductive data corroborate the generalist profile of the species and demonstrate a high degree of adaptive capacity, even in smaller tributaries.


Asunto(s)
Animales , Characidae/anatomía & histología , Estadios del Ciclo de Vida , Salud Reproductiva
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