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1.
Plant Divers ; 46(4): 491-501, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39280967

RESUMEN

Mountains are paramount for exploring biodiversity patterns due to the mosaic of topographies and climates encompassed over short distances. Biodiversity research has traditionally focused on taxonomic diversity when investigating changes along elevational gradients, but other facets should be considered. For first time, we simultaneously assessed elevational trends in taxonomic, functional, and phylogenetic diversity of woody plants in Andean tropical montane forests and explored their underlying ecological and evolutionary causes. This investigation covered four transects (traversing ca. 2200 m a.s.l.) encompassing 114 plots of 0.1 ha across a broad latitudinal range (ca. 10°). Using Hill numbers to quantify abundance-based diversity among 37,869 individuals we observed a consistent decrease in taxonomic, functional, and phylogenetic diversity as elevation increased, although the decrease was less pronounced for higher Hill orders. The exception was a slight increase in phylogenetic diversity when dominant species were over-weighted. The decrease in taxonomic and functional diversity might be attributed to an environmental filtering process towards highlands, where the increasingly harsher conditions exclude species and functional strategies. Besides, the differences in steepness decrease between Hill orders suggest that rare species disproportionately contribute to functional diversity. For phylogenetic diversity the shifting elevational trend between Hill orders indicates a greater than previously considered influence in central Andean highlands of tropical lowlands originated species with strong niche conservatism relative to distantly related temperate lineages. This could be explained by a decreasing presence and abundance of temperate, extratropical taxa towards the central Andes relative to northern or southern Andes, where they are more prevalent.

2.
Plants (Basel) ; 13(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39273881

RESUMEN

Vilca or cebil (Anadenanthera colubrina var. cebil) is a species known for its psychoactive properties and its widespread use among the pre-Hispanic peoples who inhabited the southern Andean area (southern Peru, Bolivia, northern Chile and northwest Argentina). Studies on this species, as well as on medicinal, psychoactive, or magical plants in general, tend to consider its use in post-Spanish conquest times to be scarce or irrelevant in the Andes of South America. However, based on an in-depth review of the existing literature and on ethnobotanical research conducted in markets in Argentina, Bolivia, and Peru, this paper provides an updated overview affirming the continuity of the use of this species. The results indicate a significant diversity in terms of usage types, plant parts used, treatments, and conditions in which it is applied, along with new records of vernacular names. This paper also offers an interpretation from the perspective of Andean logics, highlighting the current therapeutic effectiveness of the seeds of this plant, facilitated through a series of "movements" that aim to restore the affected person's health.

3.
Plants (Basel) ; 13(17)2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39273957

RESUMEN

The growing deforestation of tropical forests requires the implementation of restoration actions capable of assisting the recovery of biodiversity and the functioning of these ecosystems. This research aimed to identify the environmental factors that influence the abundance and diversity of woody plant recruitment in an Andean forest restoration project in Medellin (Colombia). Data from woody plant individuals taller than 80 cm were collected in 22 plots of 200·m-2. The environmental factors selected were edaphic variables, plantation structure, slope, elevation, prior land use, and landscape forest cover. Generalized linear models (GLM) were used to analyze recruitment densit and Linear Mixed Models (LMM) to assess recruited species richness, diversity, and dominance. Woody plant recruitment attributes in our study area were similar to those of secondary succession in an Andean forest, but planted trees contributed little to recruitment density and diversity. While recruitment density was affected by slope, canopy closure, and landscape forest cover, recruitment diversity was influenced by physical (bulk density) and chemical (pH, aluminum, Cation Exchange Capacity) edaphic factors, planted tree diversity (species richness and composition), canopy closure, and the mortality rate of planted trees. We conclude that sites with lower mortality rates of planted trees and denser canopies enhance both recruitment density and diversity, indicating a synergy between active restoration and passive regeneration processes.

4.
Genome Biol Evol ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235046

RESUMEN

The South American archaeological record has ample evidence of the socio-cultural dynamism of human populations in the past. This has also been supported through the analysis of ancient genomes, by showing evidence of gene flow across the region. While the extent of these signals is yet to be tested, the growing number of ancient genomes allows for more fine-scaled hypotheses to be evaluated. In this study, we assessed the genetic diversity of individuals associated with the Inka ritual, Qhapaq hucha. As part of this ceremony, one or more individuals were buried with Inka and local-style offerings on mountain summits along the Andes, leaving a very distinctive record. Using paleogenomic tools, we analyzed three individuals: two newly-generated genomes from El Plomo Mountain (Chile) and El Toro Mountain (Argentina), and a previously published genome from Argentina (Aconcagua Mountain). Our results reveal a complex demographic scenario with each of the individuals showing different genetic affinities. Furthermore, while two individuals showed genetic similarities with present-day and ancient populations from the southern region of the Inka empire, the third individual may have undertaken long-distance movement. The genetic diversity we observed between individuals from similar cultural contexts supports the highly diverse strategies the Inka implemented while incorporating new territories. More broadly, this research contributes to our growing understanding of the population dynamics in the Andes by discussing the implications and temporality of population movements in the region.

5.
mBio ; : e0160024, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258903

RESUMEN

Hantaviruses are rodent-borne viruses that cause severe disease in infected humans. In the New World, major hantaviruses include Andes virus (ANDV) and Sin Nombre virus (SNV) causing hantavirus pulmonary syndrome. In the Old World, major hantaviruses include Hantaan virus (HTNV) and Puumala virus (PUUV) causing hemorrhagic fever with renal syndrome. Here, we produced a pan-hantavirus therapeutic (SAB-163) comprised of fully human immunoglobulin purified from the plasma of transchromosomic bovines (TcB) vaccinated with hantavirus DNA plasmids coding for the major glycoproteins of ANDV, SNV, HTNV, and PUUV. SAB-163 has potent neutralizing antibodies (PRNT50 > 200,000) against the four targeted hantavirus and cross-neutralization against several other heterotypic hantaviruses. At a dosage of 10 mg/kg, SAB-163 is bioavailable in Syrian hamsters out to 70 days post-treatment with a half-life of 10-15 days. At this same dosage, SAB-163 administered 1 day before, or 5 days after exposure, protected all hamsters from lethal disease caused by ANDV. At a higher dose, partial but significant protection was achieved as late as day 6. SAB-163 also protected hamsters in the HTNV, PUUV, and SNV infection models when administered 1 day before or up to 3 days after challenge. This pan-hantavirus therapeutic is attractive because it is fully human, multi-targeted, safe, stable at 4°C, and effective in animal models. SAB-163 was evaluated for safety in GLP human tissue binding studies and a GLP rabbit toxicity study at 365 and 730 mg/kg and is investigational new drug enabled for phase 1 clinical trial(s). IMPORTANCE: This candidate polyclonal human IgG product was produced using synthetic gene-based vaccines and transgenic cows. Having now gone through cGMP production, GLP safety testing, and efficacy testing in animals, SAB-163 is the world's most advanced anti-hantavirus antibody-based medical countermeasure, aside from convalescent human plasma. Importantly, SAB-163 targets the most prevalent hantaviruses on four continents.

6.
bioRxiv ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39091768

RESUMEN

On the flanks of >6000 m Andean volcanoes that tower over the Atacama Desert, leaf-eared mice (Phyllotis vaccarum) live at extreme elevations that surpass known vegetation limits. What the mice eat in these barren, hyperarid environments has been the subject of much speculation. According to the arthropod fallout hypothesis, sustenance is provided by windblown insects that accumulate in snowdrifts ('aolian deposits'). It is also possible that mice feed on saxicolous lichen or forms of cryptic vegetation that have yet to be discovered at such high elevations. We tested hypotheses about the diet of mice living at extreme elevations on Atacama volcanoes by combining metagenomic and DNA metabarcoding analyses of gut contents with stable-isotope analyses of mouse tissues. Genomic analyses of contents of the gastrointestinal tract of a live-captured mouse from the 6739 m summit of Volcán Llullaillaco revealed evidence for an opportunistic but purely herbivorous diet, including lichens. Although we found no evidence of animal DNA in gut contents of the summit mouse, stable isotope data indicate that mice native to elevations at or near vegetation limits (~5100 m) include a larger fraction of animal prey in their diet than mice from lower elevations. Some plant species detected in the gut contents of the summit mouse are known to exist at lower elevations at the base of the volcano and in the surrounding Altiplano, suggesting that such plants may occur at higher elevations beneath the snowpack or in other cryptic microhabitats.

7.
Plants (Basel) ; 13(16)2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39204637

RESUMEN

The environmental filtering hypothesis predicts that abiotic factors restrict communities by selecting species capable of survival and persistence under specific conditions, resulting in variations in beta diversity, phylogenetic clustering, and niche differentiation among communities when studying environmental gradients. Cushion bogs and high-altitude wetlands along the Andes display homogeneous flora contrasting with zonal vegetation. Despite being influenced by microclimatic conditions, these ecosystems are subject to diverse environmental effects. Here, we test the environmental filtering hypothesis on the structure of cushion bog communities along a broad-scale latitudinal gradient from 15° S to 42° S. We analyzed 421 bogs and 293 species across three macroclimatic regions with distinct summer, winter, and transitional arid rainfall regimes. Using variance partitioning and membership-based regionalization models, we examined the impacts of climatic, edaphic, and spatial variables on beta diversity. We also assessed species' niche overlap and the influence of environmental filters on the communities' phylogenetic diversity. Results show that species turnover and niche overlap vary with macroclimatic differences, delineating three distinct regions. Notably, phylogenetic clustering in the driest part of the gradient (23° S-24° S) highlights the impact of environmental filtering. Aridity and temperature variations at a broad scale serve as environmental filters shaping the composition of bog communities across southern South America.

8.
PeerJ ; 12: e17712, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39193520

RESUMEN

Centrolenidae is a Neotropical family widely distributed in Central and South America, with its species richness concentrated in the tropical Andes. Several taxonomic problems have been identified within this family, mostly related to species with broad geographic distributions. In this study, we assessed and redefined the species boundaries of the Centrolene buckleyi species complex, and formally described two new species from the Andes of Ecuador. These new taxa are recognized by a combination of morphometric, osteological, acoustic, and genetic data. Following IUCN criteria, we propose that the two new species should to be considered as Endangered (EN), mainly because of their small distributions and habitat loss. The C. buckleyi complex provides insights into the biogeography of closely related Andean species. As in other glassfrogs, speciation in Centrolene seems to be mediated by the linearity of the Andes, where gene flow can be restricted by topography and, also, local extinctions.


Asunto(s)
Anuros , Animales , Anuros/genética , Anuros/anatomía & histología , Anuros/clasificación , Ecosistema , Ecuador , Especies en Peligro de Extinción , Filogenia , Especificidad de la Especie
9.
Viruses ; 16(7)2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39066316

RESUMEN

Hantaviruses are zoonotic agents responsible for causing Hantavirus Cardiopulmonary Syndrome (HCPS) in the Americas, with Brazil ranking first in number of confirmed HCPS cases in South America. In this study, we simulate the monthly spread of highly lethal hantavirus in natural hosts by conjugating a Kermack-McCormick SIR model with a cellular automata model (CA), therefore simultaneously evaluating both in-cell and between-cell infection dynamics in host populations, using recently compiled data on main host species abundances and confirmed deaths by hantavirus infection. For both host species, our models predict an increase in the area of infection, with 22 municipalities where no cases have been confirmed to date expected to have at least one case in the next decade, and a reduction in infection in 11 municipalities. Our findings support existing research and reveal new areas where hantavirus is likely to spread within recognized epicenters. Highlighting spatial-temporal trends and potential expansion, we emphasize the increased risk due to pervasive habitat fragmentation and agricultural expansion. Consistent prevention efforts and One Health actions are crucial, especially in newly identified high-risk municipalities.


Asunto(s)
Infecciones por Hantavirus , Orthohantavirus , Brasil/epidemiología , Animales , Infecciones por Hantavirus/epidemiología , Infecciones por Hantavirus/virología , Humanos , Reservorios de Enfermedades/virología , Síndrome Pulmonar por Hantavirus/epidemiología , Síndrome Pulmonar por Hantavirus/virología , Zoonosis/epidemiología , Zoonosis/virología
10.
Arch. cardiol. Méx ; 94(2): 169-173, Apr.-Jun. 2024. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1556913

RESUMEN

Resumen Objetivo: Presentar la experiencia en un país andino con el dispositivo OcclutechTM Duct Occluder para el cierre del conducto arterioso persistente. Método: Estudio observacional, retrospectivo, de corte transversal con análisis estadístico básico. Periodo: diciembre/2014 a diciembre/2022. Datos: historia clínica, informes de laboratorio de cateterismo. Resultados: Cuarenta y seis pacientes; de sexo femenino 71.3%, de sexo masculino 28.7%; edad: 0.6-38 años (mediana [Me]: 5.2); peso: 6.3-60 kg (Me: 16.5). Procedencia: andina 91.3%, costa 8.7%. Tipos de conducto arterioso persistente: E 54.4%, A 32.6%, D 13%. Diámetro ductal mínimo: 1.8-11.8 mm (Me: 3.5). Presión media de la arteria pulmonar previo a la oclusión: 14-67 mmHg (Me: 27). Índice de resistencias vasculares pulmonares previo a la oclusión: 0.28-4.9 UW/m2 (Me: 1.3). Fueron catalogados como conductos arteriosos persistentes hipertensivos seis de ellos. Tasa de oclusión: inmediata el 47.8%, a las 24 horas el 81%, a los seis meses el 100%. Tiempo de fluoroscopia: 2-13.8 minutos (Me: 4). Complicaciones: un dispositivo migrado. Seguimiento: 1-6.5 años. Conclusiones: El dispositivo OcclutechTM Duct Occluder fue efectivo y seguro para el cierre de conducto arterioso persistente tipo E, A y D en habitantes de baja y alta altitud, ya sea que estos hubieran sido niños o adultos, incluso cuando estos conductos arteriosos fueron hipertensivos.


Abstract Objective: To communicate the experience in an Andean country with the OcclutechTM Duct Occluder device for the closure of patent ductus arteriosus. Method: Observational, retrospective, cross-sectional study with basic statistical analysis. Period: December/2014 to December/2022. Data: medical chart, reports of catheterization. Results: Forty-six patients, female 71.3%, male 28.7%; age: 0.6-38 years-old (median [Me]: 5.2); weight: 6.3-60 kg (Me: 16.5). Origin: andean 91.3%, coast 8.7%. Types of patent ductus arteriosus: E 54.4%, A 32.6%, D 13%. Minimum ductal diameter: 1.8-11.8 mm (Me: 3.5). Mean pulmonary artery pressure prior to occlusion: 14-67 mmHg (Me: 27). Pulmonary vascular resistance index prior to occlusion: 0.28-4.9 WU/m2 (Me: 1.3). Six of them were classified as hypertensive patent ductus arteriosus. Occlusion rate: 47.8% immediate, 81% at 24 hours, 100% after six months. Fluoroscopy time: 2-13.8 minutes (Me: 4). Complications: a migrated device. Follow-up: 1-6.5 years. Conclusions: OcclutechTM Duct Occluder device was effective and safe for the closure of patent ductus arteriosus type E, A and D in low-altitude and high-altitude dwellers, whether they were children or adults, even when these ductus arteriosus were hypertensive.

11.
PhytoKeys ; 243: 15-30, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938540

RESUMEN

CarexsectionJunciformes is one of the most diverse groups of the genus in South America, consisting of approximately 30 species. Here we describe a new species, Carexrecondita, belonging to this section. We studied its placement within a molecular phylogeny of the group and found it to constitute an independent lineage. The new species is morphologically very close to C.austroamericana, from southern Patagonia, despite being phylogenetically divergent to the rest of Patagonian species of sect. Junciformes. So far, this species is known only from a few specimens recently collected in its type locality, despite growing in a well-collected area in the Andes of Metropolitana Region of Santiago, the most populated administrative region of Chile. We provide a detailed morphological description, comments on its relationship with other Southern Cone species of sect. Junciformes and relevant ecological notes.

12.
Ecol Evol ; 14(6): e11553, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38895562

RESUMEN

Plant-pollinator interactions are constrained by floral traits and available pollinators, both of which can vary across environmental gradients, with consequences for the stability of the interaction. Here, we quantified how the pollination ecology of a high-mountain hummingbird-pollinated plant changes across a progressively more stressful environmental gradient of the Venezuelan Andes. We compared pollination ecology between two populations of this plant: Piedras Blancas (PB) and Gavidia (GV), 4450 and 3600 m asl, respectively. We hypothesised that self-compatibility might be higher at the higher altitude site, however we found that flowers showed similar capacities for self-compatibility in both localities. Seed production by flowers exposed to natural pollinators was significantly higher in the lower locality, where we also found higher nectar quality, larger flowers and increased frequencies of pollinator visitations. Interestingly, the population energy offered in the nectar was the same for both localities due to the higher density and floral aggregation found in the higher altitude population. Our study demonstrates how two plant populations in different environmental conditions have different pollination ecology strategies. Pollinator visitations or their absence result in trait associations in one population that are independent in the other. These population differences are not explained by differences in pollinator assembly, but by environmental heterogeneity.

13.
PhytoKeys ; 242: 307-316, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38903848

RESUMEN

Recent exploratory field expeditions to the western slopes of the Ecuadorian Andes resulted in the discovery of a new species of Amalophyllon (Gesneriaceae). Amalophyllonmiraculum J.L.Clark, sp. nov. is described from two localities in the Centinela region in the Santo Domingo de los Tsáchilas province. The new species is differentiated from congeners by the pendent habit, basal rosette of leaves, leaf blades with deeply serrate margins, and miniature size. Based on IUCN guidelines, a preliminary conservation status is assigned as Critically Endangered (CR).


ResumenRecientes expediciones exploratorias de campo a las laderas occidentales de los Andes ecuatorianos dieron como resultado el descubrimiento de una nueva especie de Amalophyllon (Gesneriaceae). Amalophyllonmiraculum J.L.Clark, sp. nov. se describe de dos localidades de la región de Centinela en la provincia de Santo Domingo de los Tsáchilas. La nueva especie se diferencia de otros congéneres por el hábito colgante, la roseta basal de las hojas, las láminas foliares con márgenes profundamente aserrados y su tamaño en miniatura. Según las directrices de la UICN, se le asigna el estado de conservación preliminar de En Peligro Crítico (CR).

14.
Syst Biol ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38832843

RESUMEN

A fundamental objective of evolutionary biology is to understand the origin of independently evolving species. Phylogenetic studies of species radiations rarely are able to document ongoing speciation; instead, modes of speciation, entailing geographic separation and/or ecological differentiation, are posited retrospectively. The Oreinotinus clade of Viburnum has radiated recently from north to south through the cloud forests of Mexico and Central America to the Central Andes. Our analyses support a hypothesis of incipient speciation in Oreinotinus at the southern edge of its geographic range, from central Peru to northern Argentina. Although several species and infraspecific taxa of have been recognized in this area, multiple lines of evidence and analytical approaches (including analyses of phylogenetic relationships, genetic structure, leaf morphology, and climatic envelopes) favor the recognition of just a single species, V. seemenii. We show that what has previously been recognized as V. seemenii f. minor has recently occupied the drier Tucuman-Bolivian forest region from Samaipata in Bolivia to Salta in northern Argentina. Plants in these populations form a well-supported clade with a distinctive genetic signature and they have evolved smaller, narrower leaves. We interpret this as the beginning of a within-species divergence process that has elsewhere in the neotropics resulted repeatedly in Viburnum species with a particular set of leaf ecomorphs. Specifically, the southern populations are in the process of evolving the small, glabrous, and entire leaf ecomorph that has evolved in four other montane areas of endemism. As predicted based on our studies of leaf ecomorphs in Chiapas, Mexico, these southern populations experience generally drier conditions, with large diurnal temperature fluctuations. In a central portion of the range of V. seemenii, characterized by wetter climatic conditions, we also document what may be the initial differentiation of the leaf ecomorph with larger, pubescent, and toothy leaves. The emergence of these ecomorphs thus appears to be driven by adaptation to subtly different climatic conditions in separate geographic regions, as opposed to parapatric differentiation along elevational gradients as suggested by Viburnum species distributions in other parts of the neotropics.

15.
Sci Total Environ ; 941: 173671, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38825194

RESUMEN

Polylepis trees grow at elevations above the continuous tree line (3000-5000 m a.s.l.) across the Andes. They tolerate extreme environmental conditions, making them sensitive bioindicators of global climate change. Therefore, investigating their ecohydrological role is key to understanding how the water cycle of Andean headwaters could be affected by predicted changes in environmental conditions, as well as ongoing Polylepis reforestation initiatives in the region. We estimate, for the first time, the annual water balance of a mature Polylepis forest (Polylepis reticulata) catchment (3780 m a.s.l.) located in the south Ecuadorian páramo using a unique set of field ecohydrological measurements including gross rainfall, throughfall, streamflow, and xylem sap flow in combination with the characterization of forest and soil features. We also compare the forest water balance with that of a tussock grass (Calamagrostis intermedia) catchment, the dominant páramo vegetation. Annual gross rainfall during the study period (April 2019-March 2020) was 1290.6 mm yr-1. Throughfall in the Polylepis forest represented 61.2 % of annual gross rainfall. Streamflow was the main component of the water balance of the forested site (59.6 %), while its change in soil water storage was negligible (<1 %). Forest evapotranspiration was 54.0 %, with evaporation from canopy interception (38.8 %) more than twice as high as transpiration (15.1 %). The error in the annual water balance of the Polylepis catchment was small (<15 %), providing confidence in the measurements and assumptions used to estimate its components. In comparison, streamflow and evapotranspiration at the grassland site accounted for 63.7 and 36.0 % of the water balance, respectively. Although evapotranspiration was larger in the forest catchment, its water yield was only marginally reduced (<4 %) in relation to the grassland catchment. The substantially higher soil organic matter content in the forest site (47.6 %) compared to the grassland site (31.8 %) suggests that even though Polylepis forests do not impair the hydrological function of high-Andean catchments, their presence contributes to carbon storage in the litter layer of the forest and the underlying soil. These findings provide key insights into the vegetation-water­carbon nexus in high Andean ecosystems, which can serve as a basis for future ecohydrological studies and improved management of páramo natural resources considering changes in land use and global climate.


Asunto(s)
Monitoreo del Ambiente , Bosques , Ecuador , Clima Tropical , Hidrología , Cambio Climático , Suelo/química , Árboles , Altitud , Ciclo Hidrológico , Lluvia , Agua
16.
PeerJ ; 12: e17344, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38915382

RESUMEN

The Jambato Harlequin toad (Atelopus ignescens), a formerly abundant species in the Andes of Ecuador, faced a dramatic population decline in the 1980s, with its last recorded sighting in 1988. The species was considered Extinct by the IUCN until 2016, when a fortuitous discovery of one Jambato by a local boy reignited hope. In this study, we present findings from an investigation conducted in the Angamarca parish, focusing on distribution, abundance, habitat preferences, ecology, disease susceptibility, and dietary habits of the species. In one year we identified 71 individuals at different stages of development in various habitats, with a significant presence in agricultural mosaic areas and locations near water sources used for crop irrigation, demonstrating the persistence of the species in a complex landscape, with considerable human intervention. The dietary analysis based on fecal samples indicated a diverse prey selection, primarily comprising arthropods such as Acari, Coleoptera, and ants. Amphibian declines have been associated with diseases and climate change; notably, our study confirmed the presence of the pathogen Batrachochytrium dendrobatidis (Bd), but, surprisingly, none of the infected Jambatos displayed visible signs of illness. When analyzing climatic patterns, we found that there are climatic differences between historical localities and Angamarca; the temporal analysis also exposes a generalized warming trend. Finally, in collaboration with the local community, we developed a series of management recommendations for terrestrial and aquatic environments occupied by the Jambato.


Asunto(s)
Bufonidae , Ecosistema , Animales , Ecuador , Bufonidae/microbiología , Batrachochytrium , Conservación de los Recursos Naturales
17.
Front Plant Sci ; 15: 1393241, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38872876

RESUMEN

Asteraceae is the world's richest plant family and is found on all continents, in environments ranging from the coast to the highest mountains. The family shows all growth forms and, as in other angiosperm families, species richness is concentrated in tropical regions. South America has the highest diversity of Asteraceae in the world, yet taxonomic and distributional knowledge gaps remain. This study compiles an updated catalog of Asteraceae native to South America, based on national and regional checklists and ongoing large-scale flora projects. The resulting checklist includes a total of 6,940 species and 564 genera native to South America to date, which represent about a quarter of the family's global diversity. Countries already considered to be megadiverse show the greatest diversity, such as Brazil with 2,095 species, followed by Peru (1,588), Argentina (1,377), and Colombia (1,244), with this diversity mainly focused on the Brazilian Highlands and the Andes. Species endemism also peaks in Brazil, but Sørensen distances reveal the Chilean flora to be eminently different from the rest of the continent. Tribes better represented in the continent are Eupatorieae, Senecioneae and Astereae, also with a remarkably presence of entirely South American subfamilies representing earliest diverging lineages of the Asteraceae, such as Barnadesioideae, Wunderlichioideae, Famatinanthoideae, and Stifftioideae. It is estimated that the discovery and description curves have not yet stabilized, and the number of species is likely to increase by 5 to 10% in the coming years, posing major challenges to continental-scale conservation.

18.
Environ Pollut ; 355: 124089, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38729508

RESUMEN

Glacial bodies in the Peruvian Andes Mountains store and supply freshwater to hundreds of thousands of people in central Peru. Atmospheric black carbon (BC) is known to accelerate melting of snow and ice, in addition to contributing to air pollution and the health of people. Currently there is limited understanding on the sources and temporal variability of BC in valley and mountain environments in Peru. To address this problem, this study combined surface observations of BC collected during 2022-2023 with WRF model simulations and HYSPLIT trajectories to analyze the dispersion and sources of BC in valley and high elevation environments and the associated local atmospheric circulations. Results show high BC concentrations are associated with the valley-mountain wind system that occurs on both sides of the Huaytapallana mountain range. A pronounced circulation occurs on the western slopes of Huaytapallana when concentrations of BC increase during daylight hours, which transports atmospheric pollutants from cities in the Mantaro River Valley to the Huaytapallana mountain range. Low concentrations of BC are associated with circulations from the east that are channeled by the pronounced ravines of the Andes-Amazon transition. On average, during the season of highest BC concentrations (July-November), the relative contributions of fossil fuels are dominant to biomass burning at the valley observatory and are slightly lower at the Huaytapallana observatory. These results demonstrate the need to promote mitigation actions to reduce emissions of BC and air pollution associated with forest fires and local anthropogenic activity.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Atmósfera , Monitoreo del Ambiente , Hollín , Perú , Contaminantes Atmosféricos/análisis , Hollín/análisis , Atmósfera/química , Contaminación del Aire/estadística & datos numéricos
19.
Am Nat ; 203(6): 726-735, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38781524

RESUMEN

AbstractIn the world's highest mountain ranges, uncertainty about the upper elevational range limits of alpine animals represents a critical knowledge gap regarding the environmental limits of life and presents a problem for detecting range shifts in response to climate change. Here we report results of mountaineering mammal surveys in the Central Andes, which led to the discovery of multiple species of mice living at extreme elevations that far surpass previously assumed range limits for mammals. We livetrapped small mammals from ecologically diverse sites spanning >6,700 m of vertical relief, from the desert coast of northern Chile to the summits of the highest volcanoes in the Andes. We used molecular sequence data and whole-genome sequence data to confirm the identities of species that represent new elevational records and to test hypotheses regarding species limits. These discoveries contribute to a new appreciation of the environmental limits of vertebrate life.


Asunto(s)
Altitud , Animales , Ratones/genética , Ratones/fisiología , Chile , Filogenia , Distribución Animal
20.
Zookeys ; 1196: 149-175, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38566619

RESUMEN

The genus Rhinella (Bufonidae) comprises 92 species of Neotropical toads. In Colombia, Rhinella is represented by 22 recognized species, of which nine belong to the Rhinellafestae group. Over the past decade, there has been increasing evidence of cryptic diversity within this group, particularly in the context of Andean forms. Specimens of Rhinella collected in high Andean forests on both slopes of the Central Cordillera in Colombia belong to an undescribed species, Rhinellakumandaysp. nov. Genetic analyses using the mitochondrial 16S rRNA gene indicated that the individuals belong to the festae species group. However, they can be distinguished from other closely related species such as Rhinellaparaguas and Rhinellatenrec by a combination of morphological traits including the presence of tarsal fold, a moderate body size, and substantial genetic divergence in the 16S rRNA gene (> 5%). Through this integrative approach, the specimens from the Central Cordillera of Colombia are considered an evolutionary divergent lineage that is sister to R.paraguas, and described as a new species. Rhinellakumandaysp. nov. is restricted to the Central Cordillera of Colombia inhabiting both slopes in the departments of Caldas and Tolima, in an elevational range between 2420 and 3758 m. With the recognition of this new species, the genus Rhinella now comprises 93 species with 23 of them found in Colombia, and ten species endemic to the country.

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