scholarly journals American Mammals Susceptibility to Dengue According to Geographical, Environmental, and Phylogenetic Distances

2021 ◽  
Vol 8 ◽  
Author(s):  
Ángel L. Robles-Fernández ◽  
Diego Santiago-Alarcon ◽  
Andrés Lira-Noriega

Many human emergent and re-emergent diseases have a sylvatic cycle. Yet, little effort has been put into discovering and modeling the wild mammal reservoirs of dengue (DENV), particularly in the Americas. Here, we show a species-level susceptibility prediction to dengue of wild mammals in the Americas as a function of the three most important biodiversity dimensions (ecological, geographical, and phylogenetic spaces), using machine learning protocols. Model predictions showed that different species of bats would be highly susceptible to DENV infections, where susceptibility mostly depended on phylogenetic relationships among hosts and their environmental requirement. Mammal species predicted as highly susceptible coincide with sets of species that have been reported infected in field studies, but it also suggests other species that have not been previously considered or that have been captured in low numbers. Also, the environment (i.e., the distance between the species' optima in bioclimatic dimensions) in combination with geographic and phylogenetic distance is highly relevant in predicting susceptibility to DENV in wild mammals. Our results agree with previous modeling efforts indicating that temperature is an important factor determining DENV transmission, and provide novel insights regarding other relevant factors and the importance of considering wild reservoirs. This modeling framework will aid in the identification of potential DENV reservoirs for future surveillance efforts.

2020 ◽  
Author(s):  
Ángel L. Robles-Fernández ◽  
Diego Santiago-Alarcon ◽  
Andrés Lira-Noriega

ABSTRACTMany human emergent and re-emergent diseases have a sylvatic cycle. Yet, little effort has been put into discovering and modeling the wild mammal reservoirs of dengue (DENV), particularly in the Americas. Here, we show a species-level susceptibility prediction to dengue of wild mammals in the Americas as a function of the three most important biodiversity dimensions (ecological, geographical, and phylogenetic spaces), using machine learning protocols. Model predictions showed that different species of bats would be highly susceptible to DENV infections, where susceptibility mostly depended on phylogenetic relationships among hosts and their environmental requirement. Mammal species predicted as highly susceptible coincide with sets of species that have been reported infected in field studies, but it also suggests other species that have not been previously considered or that have been captured in low numbers. Also, the environment (i.e., the distance between the species’ optima in bioclimatic dimensions) in combination with geographic and phylogenetic distance is highly relevant in predicting susceptibility to DENV in wild mammals. Our results agree with previous modeling efforts indicating that temperature is an important factor determining DENV transmission, and provide novel insights regarding other relevant factors and the importance of considering wild reservoirs. This modeling framework will aid in the identification of potential DENV reservoirs for future surveillance efforts.


2014 ◽  
Vol 4 (2) ◽  
pp. 1 ◽  
Author(s):  
Tiberio C. Monterrubio-Rico ◽  
Juan Felipe Charre Medellín ◽  
Cristina Z. Colín-Soto ◽  
Livia León Paniagua

 RESUMEN Los mamíferos silvestres han sido estudiados en Michoacán desde el siglo XVIII por renombrados zoólogos y naturalistas. Sin embargo, todavía en 1949 se reconocía solo 85 especies, y hasta el año 2005 se proporcionó estimaciones completas basadas en integración de registros disponibles tanto nacionales como de colecciones científicas internacionales, ya que la información disponible para el estado se encontraba dispersa. Como resultado de proyectos recientes con nuevos registros, el objetivo de este análisis es proporcionar una cifra actualizada sobre la riqueza taxonómica de los mamíferos silvestres terrestres en el estado de Michoacán. Existen registros de 161 especies en 9 Ordenes, 25 familias, y 94 géneros que representan el 32% de las especies de México. El Orden con mayor número de especies es Chiroptera con 74 especies que representan el 53% de las especies del Orden en México. A pesar de la ubicación central de Michoacán en el país, y ser un estado muestreado por numerosos investigadores, todavía existe carencia de información para regiones remotas, y en algunos grupos de mamíferos. Por ejemplo, el jaguar, que a pesar de ser el mayor felino del país, se carecía de confirmación para el estado, afortunadamente durante 2010 se localizó una población en el estado. Otro aspecto limitante para la interpretación adecuada de la estimación actual, es la antigüedad de muchos registros, ya que los estudios más completos realizados a escala regional, como en la costa Michoacana son de hace 30 años, y durante ese periodo se ha incrementado la deforestación de selvas tropicales, por lo que desconocemos la situación actual que presentan las poblaciones de mamíferos en el estado. En Michoacán encuentran su límite más norteño en el Pacífico tres especies de amplia distribución en el Neotrópico, Tamandua mexicana,  Potos flavus y Sphiggurus mexicanus, por lo que deben limitarse áreas que protejan sus poblaciones. Palabras clave: Distribución, Mochoacán, mamíferos, especies.ABSTRACT The wild mammals in Michoacan state have been studied since the XVIII century by reknown zoologists and naturalists. However, still in 1949 only 85 mammals species were recognized, and until 2005 a complete estimate based on the integration of national and international data bases records available from Scientific collections, since all available information was scattered. As a result of recent surveys with new records, the aim of this analysis was to provide an updated statistic of the terrestrial wild mammals taxonomic richness in the Michoacan state. Available records correspond to 161 species in 9 Orders, 25 families and 94 genera which represent 32% of the Mexican mammal species. The Order with the major number of species is Chiroptera that includes 74 species thet represent 53% of the Order in Mexico. Despite its central location in the country, and considering that the state has been surveyed by several prestigious academics, there is still a lack of information for remote regions, and for some mammal groups. For example, the jaguar, even though constitute the largest wild felid in the country, no information was available for the state, fortunately during 2010 a population was localized in the state. Another limiting factor for the adequate interpretation of the current estimate is that many records are outdated, since the most complete studies performed at a regional scale, like in the Michoaca coast, are 30 years old, and during that time-frame, tropical forest loss increased dramatically, for instance, the current situation that present the mammal populations in the state are unknown. In Michoacan three species with a broad neotropical distribution present its northernmost limit on the Pacific, Tamandua mexicana, Potos flavus, and Sphiggurus mexicanus and there is the need to establish protected areas oriented to protect their populations. Key words: Distribution, Michoacan, mammals, species.


2021 ◽  
Author(s):  
Zhoujian Zhang ◽  
Michael Liu ◽  
Mark Marley ◽  
Michael Line ◽  
William Best

<p>Spectroscopic characterization of imaged exoplanets and brown dwarfs is essential for understanding their atmospheres, formation, and evolution, but such work is challenged by the unavoidably simplified model atmospheres needed to interpret spectra. While most previous work has focused on single or at most a few objects, comparing a large collection of spectra to models can uncover trends in data-model inconsistencies needed to improve model predictions, thereby leading to robust properties from exoplanet and brown dwarf spectra. Therefore, we are conducting a systematic analysis of a valuable but underutilized resource: the numerous high-quality spectra of (directly imaged and free-floating) exoplanets and brown dwarfs already accumulated by the community.<span class="Apple-converted-space"> </span></p> <p>Focusing on the cool-temperature end, we have constructed a Bayesian modeling framework using the new Sonora-Bobcat model atmospheres and have applied it to study near-infrared low-resolution spectra of >50 late-T imaged planets and brown dwarfs (≈600-1200K, ≈10-70 M<sub>Jup</sub>) and infer their physical properties (effective temperature, surface gravity, metallicity, radii, mass). By virtue of having such a large sample of high-quality spectra, our analysis identifies the systematic offsets between observed and model spectra as a function of wavelength and physical properties to pinpoint specific shortcomings in model predictions. We have also found that the spectroscopically inferred metallicities, ages, and masses of our sample all considerably deviate from expectations, suggesting the physical and chemical assumptions made within these models need to be improved to fully interpret data. Our work has established a systematic validation of cloudless model atmospheres to date and we discuss extending such analysis to wider temperature and wavelength (e.g., JWST) ranges, as well as finding new planetary-mass and brown dwarf benchmarks, in order to validate ultracool model atmospheres over larger parameter space.</p>


Weed Science ◽  
1997 ◽  
Vol 45 (2) ◽  
pp. 261-268 ◽  
Author(s):  
Francisca López-Granados ◽  
Luis García-Torres

A mathematical model of crenate broomrape populations in broad bean as affected by cropping frequency and planting dates in the absence of crenate broomrape control practices was constructed using previously reported data. In consecutive broad bean cropping, broomrape populations reached a maximum infection severity (D) of 62, 47, and 30 emerged broomrape m−2for early (mid-October), intermediate (mid-November), and late (mid-December) planting dates, respectively. The maximumDvalues were reached earlier as planting dates were brought forward, taking from 4 to 6 yr, starting from very low initial infections (D ≤0.2 emerged broomrape m−2). If broad bean was cropped every 3 yr, 15, 21, and 27 yr were needed, respectively, according to the model, to reach the maximumDfor the three planting dates considered. A sensitivity analysis was conducted to determine the effect of changing the values of the main demographic parameters in broomrape life cycle (germination, attachment, and seed loss) on the output of the model under different management strategies (planting dates and cropping frequency). Generally, an increase in seed attachment and a decrease in seed loss affected broomrape population dynamics. Between the two processes evaluated, the time taken to reach the maximum infection severity (D) was less sensitive than the maximum broomrape population values. Model predictions were validated using results from long-term field studies at the late planting date sown every year. Simulated values generated good predictions (R2= 0.82).


Oryx ◽  
2016 ◽  
Vol 51 (2) ◽  
pp. 290-297 ◽  
Author(s):  
Marcelo Mazzolli ◽  
Taiana Haag ◽  
Beatriz G. Lippert ◽  
Eduardo Eizirik ◽  
Matthias L.A. Hammer ◽  
...  

AbstractWe compared the effectiveness of various methods for surveying medium and large wild mammals in southern Oman. Working with volunteers recruited by Biosphere Expeditions, wildlife professionals and local rangers, we used direct observation, camera traps, sign surveys (tracks and/or dung) and molecular scatology to study 66 sampling units of 2 × 2 km (grid cells) in an area of 32 × 36 km during a 4-week period in February–March 2011. Sixteen mammal species were recorded, and the largest numbers of species were recorded by sign surveys and camera traps (both n = 9); sign surveys, direct sightings and DNA scatology recorded species across the largest number of grid cells. For species with a sample size large enough for comparison (i.e. detected in ≥ 8 grid cells), DNA scatology proved most effective for detecting caracal Caracal caracal, signs for hyaena Hyaena hyaena, ibex Capra nubiana, porcupine Hystrix indica and hyrax Procavia capensis, and signs and direct sightings for mountain gazelle Gazella gazella. Clustering, in which records from multiple methods are either adjacent or overlapping, was highest (≥ 76%) for the wolf Canis lupus, porcupine, ibex and gazelle. Our results indicate the best methods to detect and record the distributions of individual species in the study area, and demonstrate the advantage of using multiple methods to reduce the risk of false absences or partial detections. Our findings also highlight the potential of clustering as a means of cross-checking results of observations that are skill-dependent, which is particularly useful when employing a large workforce.


2020 ◽  
Author(s):  
Brian Wood ◽  
Riccardo S. Millar ◽  
Nicholas Wright ◽  
Joshua Baumgartner ◽  
Hannah Holmquist ◽  
...  

In many regions of sub Saharan Africa large mammals occur in human-dominated areas, yet their community composition and species-specific densities have rarely been described in areas occupied by traditional hunter-gatherers and pastoralists. Surveys of mammal populations in such areas provide important measures of biodiversity and provide ecological context for understanding hunting practices. Using a sampling grid centered on a Hadza hunter-gatherer camp and covering 36 km² of semi-arid savannah in northern Tanzania, we assessed mammals using camera traps (n = 19 stations) for c. 5 months (2,182 trap nights). In the study area (Tli’ika in the Hadza language), we recorded 36 wild mammal species, resembling a near complete mammal community. Rarefaction curves suggest that sampling effort was sufficient to capture mammal species richness. Species-specific densities were estimated using a random encounter model and site- and species’ body mass- specific estimates of the area sampled at each camera; confidence intervals were estimated using bootstrapping. Point estimates of densities varied by c. four orders of magnitude, from 0.003 ind./km² (African wild dog) to 27.5 ind./km² (Kirk’s dik dik). Densities of livestock (cattle, donkey, sheep and goat) were high, particularly when estimated using directly observed herd sizes. Cumulative biomass density of herbivorous livestock species exceeded that of all wild mammals by a factor of 3.3-38.7. We compare our study’s data to camera trap rates recorded in a fully protected area of northern Tanzania with similar precipitation (Lake Manyara National Park), revealing that abundance indices of most wildlife species in Tli’ika were much lower. We discuss how these data inform studies of Hadza hunting and models of hunter-gatherer foraging ecology and diet.


2020 ◽  
Vol 10 (2) ◽  
pp. 1
Author(s):  
Yariely del Rocío Balam-Ballote ◽  
José Adrián Cimé-Pool ◽  
Silvia Filomena Hernández-Betancourt ◽  
Juan Manuel Pech-Canché ◽  
Juan Carlos Sarmiento-Pérez ◽  
...  

RESUMENEl conocimiento de la fauna silvestre presente en un sitio determinado es importante para implementar estrategias de conservación de la diversidad biológica. El objetivo de este trabajo fue elaborar una lista de los mamíferos silvestres colectados y registrados en el ejido X-can, municipio de Chemax, Yucatán, México. Para este estudio se utilizaron técnicas etnozoológicas tales como entrevistas y talleres de diagnóstico participativo. También se realizaron recorridos en diversos puntos del ejido para el registro de especies a través de métodos directos (avistamientos, trampas Tomahawk, Sherman, redes) e indirectos (huellas, excretas, madrigueras). En total se registraron 31 especies, 20 familias y siete órdenes. Los órdenes más diversos fueron Chiroptera y Rodentia con nueve especies cada uno, seguido por Carnivora con siete. Las especies Coendou mexicanus, Dasyprocta punctata, Cuniculus paca, Panthera onca, Herpailurus yagouaroundi, Eira barbara, Mustela frenata y Dicotyles crassus se registraron únicamente por técnicas sociales. Durante el estudio se identificaron cinco usos tales como alimento, medicinal, mascota, artesanal y ceremonial; en este último especies, como el venado cola blanca, el pecarí de collar y el tepezcuintleson usadas en la ceremonia denominada Ch’a’acháak. La especie Odocoileus virginianus fue la que presentó mayor número de usos (4). El ejido X-can posee fragmentos de selva mediana subcaducifolia con especies de mamíferos prioritarios para la conservación. Actividades como el ecoturismo integral podrían garantizar a mediano y largo plazo la conservación de la biodiversidad presente, así mismo, es indispensable difundir la importancia ecológica y económica de los mamíferos entre los pobladores.Palabras clave: Conservación, inventarios, selva mediana subcaducifolia, uso de mamíferos, Yucatán.ABSTRACTThe wildlife knowledge present in a given site is important to implement strategies for the conservation of biological diversity. The objective of this work was to make a list of the wild mammals collected and registered in the ejido X-Can, municipality of Chemax, Yucatán, México. For this study, ethnozoological techniques such as interviews and participatory diagnostic workshops were used. Trail tours were also carried out in various points of the ejido for the registration of species through direct methods (sightings, Tomahawk, Sherman traps, nets) and indirect (footprints, excreta, burrows). 31 species, 20 families and seven orders were recorded. The most diverse orders were Chiroptera and Rodentia with nine species each, followed by Carnivora with seven species. The species Coendou mexicanus, Dasyprocta punctata, Cuniculus paca, Panthera onca, Herpailurus yagouaroundi, Eira barbara, Mustela frenata and Dicotyles crassus were only registered by social techniques. During the study, five types of uses were identified such as food, medicinal, pet, artisanal and ceremonial use; in the latter, species such as the white-tailed deer, the collared peccary and the tepezcuintle are used in the ceremony called Ch’a’acháak. The species Odocoileus virginianus was the one with the highest number of uses (4). The ejido X-can has fragments of medium-deciduous forest with priority mammal species for conservation. Activities such as integral ecotourism could guarantee the conservation of the present biodiversity in the medium and long term. Likewise, it is essential to disseminate the ecological and economic importance of mammals among the inhabitants.Key words: Conservation, inventories, medium subdeciduous forest, use of mammals, Yucatan.


2021 ◽  
Vol 9 (1-2) ◽  
pp. 21-34
Author(s):  
Md Amdadul Haque ◽  
M Monirul H Khan ◽  
Md Mofizul Kabir

The status of mammals in Dinajpur district was studied from October 2016 to November 2017. For inventory and assessment of wild mammal’s belt-transect sampling, box trap survey, mist netting, night survey and questionnaire survey methods were used. A total of 22 species of mammals belonging to 11 families and 5 orders were recorded. Of the recorded species 8 were rodents, 1 hare, 1 shrew, 7 bats and 5 carnivores. Muridae appeared as the largest family containing 8 species. A total of 9 species (41%) were recorded as “very common”, 6 species (27%) “common”, 4 species (18%) “uncommon”, and 3 species (14%) “rare”. Among all the mammalian species, 41% (9 species) were nocturnal, 14% (3 species) crepuscular, 37% (8 species) metaturnal and 9% (2 species) diurnal. On the other hand, 55% (12 species) of mammals were terrestrial, 9% (2 species) arboreal, 32% (7 species) aerial and 4% (1 species) aquatic mammals. Of all the recorded species, 32% (7 species) were herbivores followed by 27% (6 species) carnivores, 5% (1 species) opportunists while frugivores and insectivores were 18% (4 species) each. About 19% (4 species) of the known species are nationally threatened comprising of Endangered (5%), Vulnerable (5%) and Near Threatened (9%) and Least Concern (81%). Based on the habitats, 14 species (64%) were recorded from forests, 7 (31%) from homestead vegetation’s and 1 (5%) species from wetlands. A good number of individuals (n=12) of the nationally threatened Bengal Fox (Vulpes bengalensis) were found in the study area and two mammal species, Indian Hare (Lepus nigricollis) and Large Indian Civet (Viverra zibetha) have been locally facing the threat of extirpation. The mammalian diversity in the natural forests (64%) was higher than that of the other habitats. Different anthropogenic threats, especially hunting by ethnic Santal people (frequency of observation 24 times, impact point 4), exist in the study area. The major proposed actions for the study area are habitat restoration, increase public awareness and conflict management. Jahangirnagar University J. Biol. Sci. 9(1 & 2): 21-34, 2020 (June & December)


Zoodiversity ◽  
2020 ◽  
Vol 54 (5) ◽  
pp. 411-418
Author(s):  
I. A. Akimov ◽  
Yu. M. Didyk

Trichinellosis is one of the most dangerous helminthic diseases common to humans and animals. It is caused by the nematodes from the Trichinella complex. Trichinella infections found in almost all mammal species, as well as reptiles and birds. In Ukraine Trichinella infection was detected in humans, domestic pigs and games. More than 1 500 cases of human trichinellosis were found in Ukraine over the past 30 years. Infected game are the main source of human Trichinella infection in recent time. Trichinella infection detected in all regions of Ukraine. Larvae were found in 3% of investigated wild boars, 15.5% wolves, 16% red foxes, 12% martens, 10% badgers and 20% raccoon dogs. Wolves and foxes were found to be the main reservoir of Trichinella in a sylvatic cycle. Our studies demonstrate the presence of tree species of Trichinella in Ukraine: T. britovi (ITRC codes: ISS1590, 1591, 1592, 1593) was found in wild boars, wolves, foxes and martens in all Ukraine; T. spiralis (ISS1594) was found in wild boars from Zhytomir and Mykolaiv regions; T. nativa (ISS1595) was found in wolves and foxes from Chernihiv, Sumy, Poltava and Kherson regions. Mixed infections (T. britovi-T. spiralis) were found in southern regions.


Weed Science ◽  
1995 ◽  
Vol 43 (2) ◽  
pp. 247-257 ◽  
Author(s):  
James C. Barbour ◽  
David C. Bridges

A model of competition for light between peanut and three broadleaf weed species has been developed to run with the PNUTGRO model. The model simulates shading of the peanut canopy by reducing the total daily PAR received by the peanuts in a manner that realistically represents timing and quantity of light capture by the weeds. Data were collected in nursery plots of Florida beggarweed, sicklepod, and wild poinsettia in 1989, 1990, and 1991. These data provided the values for the critical parameters: maximum attenuation of PAR by the weed, time when the weed overtops the peanut canopy, time when maximum attenuation is reached, and the distance of influence of the weed. Florida beggarweed overtopped the peanut canopy 52 DAP, and reduced PAR reaching the peanuts 45% by 73 DAP. Sicklepod overtopped the peanut canopy 42 DAP and reached an attenuation of 41% 79 DAP. Wild poinsettia overtopped the peanut canopy 44 DAP, and had an attenuation value of 39% 85 DAP. The distances of influence were 162, 150, and 192 cm for Florida beggarweed, sicklepod, and wild poinsettia, respectively. Observed yield losses in the distance of influence were 26, 27, and 22%, respectively. The model predictions accounted for at least 90% of the yield losses observed in field studies. The model also proved capable of simulating competitive differences between morphologically and phenologically different populations of Florida beggarweed. Simulation models will play an important role in reducing the expenditure of time and resources required to document yield losses due to weeds in peanuts.


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