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1.
Rev. biol. trop ; Rev. biol. trop;72(1): e54616, ene.-dic. 2024. tab, graf
Article in English | LILACS, SaludCR | ID: biblio-1559317

ABSTRACT

Abstract Introduction: Despite sensory enrichment being critical for ensuring the well-being of captive wild animals, smells are not being included in enrichment protocols for birds. For this group, neophobia can be a problem when it comes to implementing new enrichment devices. Objective: To explore how participation in an olfactory enrichment and latency times varies between bird taxonomic groups (Amazona spp. / Ara spp. / Ramphastos spp.). Methods: We exposed 257 birds to a scent enrichment, and we recorded which individuals engaged with it and the time they took to interact with it. Results: We discovered that participation by toucans in the enrichment was higher compared to amazons and macaws. Furthermore, latency time to interact with the enrichment was higher in amazons that in the other species. Our findings could suggest that toucans are neophilic species which could benefit from higher exploration rates. Amazons on the contrary seem to be particularly neophobic, possibly because of their less opportunistic feeding habits compared to toucans and their higher vulnerability to predation compared to macaws. Conclusion: These results point out that toucans would be more inclined to engage in environmental enrichments, while a more natural design using smells inside familiar objects could be a more successful enrichment for psittacids.


Resumen Introducción: A pesar de que el enriquecimiento sensorial es fundamental para garantizar el bienestar de los animales silvestres en cautiverio, los olores no son incluidos de forma rutinaria en los protocolos de enriquecimiento para aves. Además, en el caso de estos animales, la neofobia puede ser un problema a la hora de implementar nuevos dispositivos de enriquecimiento. Objetivo: Explorar cómo varía la participación y la latencia en la interacción con un enriquecimiento olfativo entre grupos taxonómicos de aves (Amazona spp. / Ara spp. / Ramphastos spp.). Métodos: Expusimos a 257 aves a un enriquecimiento olfativo y registramos qué individuos participaron y el tiempo que tardaron en interactuar con él. Resultados: La participación en el enriquecimiento fue mayor en los tucanes en comparación con las amazonas y los guacamayos. Además, el tiempo de latencia para interactuar con el enriquecimiento fue mayor en las amazonas que en las otras especies. Nuestros hallazgos sugieren que los tucanes son especies neofílicas que podrían beneficiarse de tasas de exploración más altas. Por otro lado, las amazonas parecen ser particularmente neofóbicas, posiblemente debido a sus hábitos alimenticios menos oportunistas en comparación con los tucanes y a su mayor vulnerabilidad a la depredación en comparación con los guacamayos. Conclusión: Estos resultados señalan que los tucanes serían más proclives a participar en enriquecimientos ambientales, mientras que un diseño que utilice olores dentro de objetos más naturales o familiares podría ser más exitoso para las psitácidas.


Subject(s)
Animals , Parrots/growth & development , Animal Welfare , Amazona/growth & development , Refugium , Costa Rica
2.
J Evol Biol ; 37(10): 1181-1193, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-39167704

ABSTRACT

Glacial periods have been considered as inhospitable environments that consist of treeless vegetation at higher latitudes. The fossil record suggests many species survived the Last Glacial Maximum within refugia, usually at lower latitudes. However, phylogeographic studies have given support to the existence of previously unknown high-latitude refugia that were not detected in the fossil record. Here, we test the hypothesis that cold-tolerant trees of Patagonia survived cold periods in microclimatically favourable locales where hybridization occurred between sister taxa. To study local presence through glacial periods in multiple refugia, we used pollen records and genetic information (isozymes, microsatellites, and combined nuclear and chloroplast DNA sequences) of population pairs of Nothofagus antarctica and N. pumilio that belong to the ancient subgenus Nothofagus which can potentially hybridize in nature, along their entire latitudinal range in Patagonia. Studied species share the N. dombeyi type pollen, which was abundant at >20% in the northernmost latitudinal bands (35-43°S), even during the Last Glacial Maximum. Mid- and southern latitudinal records (44-55°S) yielded lower abundances of ~10% that increased after c. 15.0 cal. ka BP. Therefore, fossil pollen evidence suggests a long-lasting local presence of Nothofagus throughout glacial-interglacial cycles but mostly as small populations between 44°S and 51°S. We found species-specific and shared genetic variants, the latter of which attained relatively high frequencies, thus providing evidence of ancestral polymorphisms. Populations of each species were similarly diverse, suggesting survival throughout the latitudinal range. Estimates of coalescent divergence times were broadly synchronous across latitudes, suggesting that regional climates similarly affected populations and species that hybridized through climate cycles, fostering local persistence.


Subject(s)
Hybridization, Genetic , Refugium , Biological Evolution , Pollen/genetics , DNA, Chloroplast/genetics , Phylogeography , Microsatellite Repeats , Genetic Variation
3.
J Therm Biol ; 123: 103893, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38924931

ABSTRACT

Species are expected to migrate to higher latitudes as warming intensifies due to anthropogenic climate change since physiological mechanisms have been adapted to maximize fitness under specific temperatures. However, literature suggests that upwellings could act as thermal refugia under climate warming protecting marine ecosystem diversity. This research aimed to predict the effects of climate warming on commercial and non-commercial fish species reported in official Mexican documents (>200 species) based on their thermal niche to observe if upwellings can act as potential thermal refugia. Present (2000-2014) and Representative Concentration Pathway (6.0 and 8.5) scenarios (2040-2050 and 2090-2100) have been considered for this work. Current and future suitability patterns, species distribution, richness, and turnover were calculated using the minimum volume ellipsoids as algorithm. The results in this study highlight that beyond migration to higher latitudes, upwelling regions could protect marine fishes, although the mechanism differed between the innate characteristics of upwellings. Most modeled species (primarily tropical fishes) found refuge in the tropical upwelling in Northern Yucatan. However, the highest warming scenario overwhelmed this region. In contrast, the Baja California region lies within the Eastern Boundary Upwelling Systems. While the area experiences an increase in suitability, the northern regions have a higher upwelling intensity acting as environmental barriers for many tropical species. Conversely, in the southern regions where upwelling is weaker, species tend to congregate and persist even during elevated warming, according to the turnover analysis. These findings suggest that tropicalization in higher latitudes may not be as straightforward as previously assumed. Nevertheless, climate change affects numerous ecosystem features, such as trophic relationships, phenology, and other environmental variables not considered here. In addition, uncertainty still exists about the assumption of increasing intensity of upwelling systems.


Subject(s)
Climate Change , Fishes , Animals , Fishes/physiology , Refugium , Mexico , Ecosystem , Global Warming , Temperature
4.
PLoS One ; 19(5): e0304756, 2024.
Article in English | MEDLINE | ID: mdl-38820545

ABSTRACT

Climate adaptation corridors are widely recognized as important for promoting biodiversity resilience under climate change. Central America is part of the Mesoamerican biodiversity hotspot, but there have been no regional-scale analyses of potential climate adaptation corridors in Central America. We identified 2375 potential corridors throughout Central America that link lowland protected areas (≤ 500 m) with intact, high-elevation forests (≥ 1500 m) that represent potential climate change refugia. Whereas we found potential corridors in all Central American countries, potential corridors in Panama, Belize, and Honduras were most protected (medians = 64%, 49%, and 47%, respectively) and potential corridors in El Salvador were least protected (median = 10%). We also developed a corridor priority index based on the ecological characteristics and protected status of potential corridors and their associated start and end points. Compared to low- and medium-priority corridors, high-priority corridors (n = 160; top 7% of all corridors) were generally more protected, forested, and distributed across wider elevational gradients and more Key Biodiversity Areas, but also generally linked larger lowland protected areas to target areas that were larger, more protected, and spanned wider elevational gradients. For example, based on median values, high-priority corridors were 9% more protected and overlapped with 2-3 more Key Biodiversity Areas than low- and medium-priority corridors. Although high-elevation targets spanned considerably wider elevational gradients than lowland protected areas (medians = 695 vs. 142 m, respectively) and thus may be more likely to support refugia, they were considerably smaller than lowland protected areas (medians = 11 vs. 50 km2 respectively) and mostly unprotected (median = 4% protection). This initial, regional assessment can help prioritize locations for finer-scale research, conservation, and restoration activities in support of climate adaptation corridors throughout Central America and highlights the need for greater conservation of potential high-elevation refugia.


Subject(s)
Biodiversity , Climate Change , Conservation of Natural Resources , Central America , Forests , Refugium
5.
Nature ; 629(8010): 114-120, 2024 May.
Article in English | MEDLINE | ID: mdl-38538797

ABSTRACT

Mountain ranges contain high concentrations of endemic species and are indispensable refugia for lowland species that are facing anthropogenic climate change1,2. Forecasting biodiversity redistribution hinges on assessing whether species can track shifting isotherms as the climate warms3,4. However, a global analysis of the velocities of isotherm shifts along elevation gradients is hindered by the scarcity of weather stations in mountainous regions5. Here we address this issue by mapping the lapse rate of temperature (LRT) across mountain regions globally, both by using satellite data (SLRT) and by using the laws of thermodynamics to account for water vapour6 (that is, the moist adiabatic lapse rate (MALRT)). By dividing the rate of surface warming from 1971 to 2020 by either the SLRT or the MALRT, we provide maps of vertical isotherm shift velocities. We identify 17 mountain regions with exceptionally high vertical isotherm shift velocities (greater than 11.67 m per year for the SLRT; greater than 8.25 m per year for the MALRT), predominantly in dry areas but also in wet regions with shallow lapse rates; for example, northern Sumatra, the Brazilian highlands and southern Africa. By linking these velocities to the velocities of species range shifts, we report instances of close tracking in mountains with lower climate velocities. However, many species lag behind, suggesting that range shift dynamics would persist even if we managed to curb climate-change trajectories. Our findings are key for devising global conservation strategies, particularly in the 17 high-velocity mountain regions that we have identified.


Subject(s)
Altitude , Animal Migration , Biodiversity , Geographic Mapping , Global Warming , Animals , Africa, Southern , Brazil , Conservation of Natural Resources , Global Warming/statistics & numerical data , Humidity , Indonesia , Rain , Refugium , Satellite Imagery , Species Specificity , Temperature , Time Factors
6.
J Therm Biol ; 114: 103495, 2023 May.
Article in English | MEDLINE | ID: mdl-37276747

ABSTRACT

Ocean warming is expected to occur due to anthropogenic climate change bringing a spatial shift of marine communities. Experimental data that characterize the aerobic power budget via an aerobic scope, thermal metabolic scope, or thermal preferences have been proposed as tools that can describe species distribution since they characterize species fitness or performance under different temperatures. This study tested the potential relationship between observed occurrences and different physiological studies in the Americas for 11 commercially important species in Mexico. Projections were also developed for Mexico's exclusive economic zone under different climate warming scenarios. The physiological data were fitted from optimum up to pejus temperatures and projected to sea surface temperatures for present (2003-2014) and Representative Concentration Pathway (RCP) scenarios (RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5) for the period 2040-2050 and 2090-2100. For species with wide distributions in the Americas, the number of occurrences reported decreases at higher latitudes related to the decrease in species performance calculated from laboratory experiments. In addition, higher species occurrences are usually reported around optimum temperatures. Overall, the results suggest that pejus temperatures likely restrict latitudinal distribution, at least for widely distributed taxons. Regarding Mexican projections, the results varied widely by species. For example, in the Atlantic Ocean, Octopus maya and Panulirus argus are vulnerable to warming scenarios, while Centropomus undecimalis is not. Interestingly, northern Campeche Bank, the Gulf of California, and Western Baja California may act as thermal refugia for marine species indicating they could be assigned as protected areas to support fisheries throughout the Mexican exclusive economic zone. This research adds to the increasing evidence of the relationship between thermal niche and wild population distribution.


Subject(s)
Climate Change , Environment , Mexico , Temperature , Refugium , Ecosystem
7.
Conserv Biol ; 37(4): e14087, 2023 08.
Article in English | MEDLINE | ID: mdl-36919472

ABSTRACT

Refugia-based conservation offers long-term effectiveness and minimize uncertainty on strategies for climate change adaptation. We used distribution modelling to identify climate change refugia for 617 terrestrial mammals and to quantify the role of protected areas (PAs) in providing refugia across South America. To do so, we compared species potential distribution across different scenarios of climate change, highlighting those regions likely to retain suitable climatic conditions by year 2090, and explored the proportion of refugia inside PAs. Moist tropical forests in high-elevation areas with complex topography concentrated the highest local diversity of species refugia, although regionally important refugia centers occurred elsewhere. Andean-Amazon forests contained climate change refugia for more than half of the continental species' pool and for up to 87 species locally (17 × 17 km2 grid cell). The highlands of the southern Atlantic Forest also included megadiverse refugia for up to 76 species per cell. Almost half of the species that may find refugia in the Atlantic Forest will do so in a single region-the Serra do Mar and Serra do Espinhaço. Most of the refugia we identified, however, were not in PAs, which may contain <6% of the total area of climate change refugia, leaving 129-237 species with no refugia inside the territorial limits of PAs of any kind. Our results reveal a dismal scenario for the level of refugia protection in some of the most biodiverse regions of the world. Nonetheless, because refugia tend to be in high-elevation, topographically complex, and remote areas, with lower anthropogenic pressure, formally protecting them may require a comparatively modest investment.


Identificación de refugios para la biodiversidad de Sudamérica ante el cambio climático Resumen Las estrategias de conservación basadas en refugios ofrecen efectividad a largo plazo y minimizan la incertidumbre sobre las estrategias de adaptación al cambio climático. Utilizamos modelos de distribución para identificar los refugios del cambio climático de 617 especies de mamíferos terrestres y cuantificar el papel de las áreas protegidas en la provisión de refugios en Sudamérica. Para esto, comparamos la distribución potencial de las especies en diferentes escenarios de cambio climático, destacando las regiones que probablemente conservarán las condiciones climáticas adecuadas para el año 2090, y exploramos la proporción de refugios dentro de las áreas protegidas. Los bosques tropicales húmedos de zonas de gran altitud y topografía compleja concentraron la mayor diversidad local de refugios de especies, aunque también hubo centros de refugio de importancia regional en otras localidades. Los bosques amazónicos andinos albergaron los refugios ante el cambio climático de más de la mitad del conjunto de especies continentales y para hasta 87 especies a escala local (celda cuadriculada de 17 × 17 km2 ). Las tierras altas del sur del Bosque Atlántico también incluyeron refugios megadiversos para hasta 76 especies por celda. Casi la mitad de las especies que pueden refugiarse en el Bosque Atlántico lo harán en una sola región: la Serra do Mar y la Serra do Espinhaço. Sin embargo, la mayoría de los refugios que identificamos no estaban en áreas protegidas, las cuales pueden contener <6% del área total de refugios del cambio climático, dejando entre 129 y 237 especies sin refugio dentro de los límites territoriales de las áreas protegidas de cualquier tipo. Nuestros resultados revelan un panorama desolador para el nivel de protección de los refugios en algunas de las regiones con mayor biodiversidad del mundo. No obstante, dado que los refugios suelen encontrarse en zonas remotas de gran altitud con topografía compleja y menor presión antropogénica, protegerlos formalmente puede requerir una inversión comparativamente modesta.


Subject(s)
Climate Change , Conservation of Natural Resources , Animals , Conservation of Natural Resources/methods , Biodiversity , Forests , Mammals , South America , Ecosystem
8.
PLoS One ; 18(2): e0280852, 2023.
Article in English | MEDLINE | ID: mdl-36753468

ABSTRACT

Live coral cover has declined precipitously on Caribbean reefs in recent decades. Acropora cervicornis coral has been particularly decimated, and few Western Atlantic Acropora spp. refugia remain. Coral Gardens, Belize, was identified in 2020 as a long-term refugium for this species. This study assesses changes in live A. cervicornis coral abundance over time at Coral Gardens to monitor the stability of A. cervicornis corals, and to explore potential threats to this important refugium. Live coral cover was documented annually from 2012-2019 along five permanent transects. In situ sea-surface temperature data were collected at Coral Gardens throughout the study period and compared with calibrated satellite data to calculate Maximum Monthly Mean (MMM) temperatures and Degree Heating Weeks (DHW). Data on bathymetry, sediment, substrate, herbivore abundance, and macroalgal abundance were collected in 2014 and 2019 to assess potential threats to Coral Gardens. Live coral cover declined at all five transect sites over the study period. The greatest loss of live coral occurred between 2016 and 2017, coincident with the earliest and highest maximum average temperatures recorded at the study site, and the passage of a hurricane in 2016. Structural storm damage was not observed at Coral Gardens, though live coral cover declined after the passage of the storm. Uranium-thorium (230Th) dating of 26 dead in situ fragments of A. cervicornis collected in 2015 from Coral Gardens revealed no correlation between coral mortality and tropical storms and hurricanes in the recent past. Our data suggest that several other common drivers for coral decline (i.e. herbivory, predation, sedimentation, pH) may likely be ruled out for Coral Gardens. At the end of the study period, Coral Gardens satisfied most criteria for refugium status. However, the early onset, higher mean, and longer duration of above-average temperatures, as well as intermittent temperature anomalies likely played a critical role in the stability of this refugium. We suggest that temperature stress in 2016 and perhaps 2015 may have increased coral tissue vulnerability at Coral Gardens to a passing hurricane, threatening the status of this unique refugium.


Subject(s)
Anthozoa , Refugium , Animals , Gardens , Belize , Coral Reefs
9.
New Phytol ; 237(3): 714-733, 2023 02.
Article in English | MEDLINE | ID: mdl-35037253

ABSTRACT

Tropical forest function is of global significance to climate change responses, and critically determined by water availability patterns. Groundwater is tightly related to soil water through the water table depth (WT), but historically neglected in ecological studies. Shallow WT forests (WT < 5 m) are underrepresented in forest research networks and absent in eddy flux measurements, although they represent c. 50% of the Amazon and are expected to respond differently to global-change-related droughts. We review WT patterns and consequences for plants, emerging results, and advance a conceptual model integrating environment and trait distributions to predict climate change effects. Shallow WT forests have a distinct species composition, with more resource-acquisitive and hydrologically vulnerable trees, shorter canopies and lower biomass than deep WT forests. During 'normal' climatic years, shallow WT forests have higher mortality and lower productivity than deep WT forests, but during moderate droughts mortality is buffered and productivity increases. However, during severe drought, shallow WT forests may be more sensitive due to shallow roots and drought-intolerant traits. Our evidence supports the hypothesis of neglected shallow WT forests being resilient to moderate drought, challenging the prevailing view of widespread negative effects of climate change on Amazonian forests that ignores WT gradients, but predicts they could collapse under very strong droughts.


O funcionamento da floresta tropical é de importância global para as respostas às mudanças climáticas e é criticamente determinado pelos padrões de disponibilidade de água. A água subterrânea está intimamente relacionada à água do solo através da profundidade do lençol freático, que tem sido historicamente negligenciado em estudos ecológicos. Florestas com lençol freático raso (< 5 m) estão sub-representadas nas redes de pesquisa florestal e ausentes nas medições de fluxo de gases, embora representem ~ 50% da Amazônia e devam responder de forma diferente às secas relacionadas às mudanças globais. Aqui revisamos os padrões de profundidade do lençol freático e suas consequências para plantas, resultados emergentes, e avançamos em um modelo conceitual que integra o ambiente e as distribuições de características funcionais para prever os efeitos das mudanças climáticas. As florestas com lençol freático raso têm uma composição de espécies distinta, com árvores mais aquisitivas na obtenção de recursos e hidrologicamente vulneráveis, dosséis mais baixos e menor biomassa do que as florestas com lençol freático profundo. Durante os anos climáticos 'normais', as florestas com lençol freático raso têm maior mortalidade e menor produtividade do que as florestas com lençol freático profundo, mas durante secas moderadas, a mortalidade é amortecida e a produtividade aumenta. No entanto, durante secas severas, as florestas com lençol freático raso podem ser mais sensíveis devido às raízes superficiais e características funcionais de intolerância à seca. Nossas evidências apoiam a hipótese de que as florestas com lençol freático raso, historicamente negligenciadas, sejam resilientes à seca moderada, desafiando a visão predominante dos efeitos negativos generalizados da mudança climática nas florestas amazônicas que ignora gradientes de profundidade do lençol freático, mas prevê que elas podem entrar em colapso sob secas muito fortes.


La función de los bosques tropicales es de importancia mundial para las respuestas al cambio climático y está críticamente determinada por los patrones de disponibilidad de agua. El agua subterránea está estrechamente relacionada con el agua del suelo a través de la profundidad del nivel freático (NF), pero históricamente se há negligenciado en los estudios ecológicos. Los bosques con NF poco profundos (NF < 5 m) están subrepresentados en las redes de investigación forestal y ausentes en las mediciones de flujo de gases, aunque representan ~ 50% de la Amazonía y se espera que respondan de manera diferente a las sequías relacionadas con el cambio climático global. Aquí revisamos los patrones de NF y las consecuencias para las plantas, los resultados emergentes y avanzamos en un modelo conceptual que integra distribuciones ambientales y de rasgos funcionales para predecir los efectos del cambio climático. Los bosques con NF poco profundos tienen una composición de especies distinta, con árboles más adquisitivos en la obtención de recursos e hidrológicamente más vulnerables, dosel más bajo y menor biomasa que los bosques de NF profundo. Durante los años climáticos 'normales', los bosques con NF poco profundos tienen una mayor mortalidad y menor productividad que los bosques con NF profundos, pero durante sequías moderadas la mortalidad se amortigua y la productividad aumenta. Sin embargo, durante una sequía severa, los bosques de NF poco profundos pueden ser más sensibles debido a raíces poco profundas y rasgos de intolerancia a la sequía. Nuestra evidencia apoya la hipótesis de que los bosques de NF poco profundos, mayoritariamente desconsiderados, son resistentes a sequías moderadas, desafiando la visión predominante de impactos negativos generalizados del cambio climático en los bosques amazónicos, que ignora los gradientes de NF, pero predice que podrían colapsar bajo sequías muy fuertes.


Subject(s)
Droughts , Groundwater , Refugium , Forests , Trees/physiology , Climate Change , Water , Tropical Climate
10.
Acta sci., Biol. sci ; 45: e63386, 2023. tab, graf, ilus
Article in English | VETINDEX | ID: biblio-1427183

ABSTRACT

The increasing losses of original features of many riverine environments and the consequent decline of native aquatic species are now a widely recognized problem. The main river basins of South America have been undergoing constant changes in their communities of fish, with native migratory species disappearing and the rising of sedentary exotic ones. However, few studies report experiments that qualify and/or quantify this correlation. Three experiments were conducted to evaluate the predation mortality of two species of fish larvae (native and non-native) regarding their habitat features. The hypothesis that natural features of habitat (aquatic vegetation and water turbidity) controls the survival rates of fish larvae was tested. The experiments highlight the importance of community structure on population dynamics. The native fish larvae showed to be more adapted than the non-native to using the aquatic plants for refuge. The habitat complexity can be closely related to the persistence of native migratory fish species.(AU)


Subject(s)
Animals , Biodiversity , Fishes/physiology , Aquatic Flora , Ecosystem , Refugium
11.
Sci. agric ; 80: e20220044, 2023. tab, mapas
Article in English | VETINDEX | ID: biblio-1427885

ABSTRACT

Climate change represents one of the greatest threats to global biodiversity. We investigate how climate change will affect the future potential distribution of tree species in subtropical high montane habitats in the Atlantic Forest and identify potential climate refuges for these species. The most frequent and exclusive species in this ecosystem were selected and geographic coordinates were compiled. The maximum entropy algorithm was used for climatic niche modeling. Two scenarios for 2061-2080 were considered for future predictions, one low impact (RCP 4.5) and one high impact (RCP 8.5). Isothermality, mean temperature in the driest quarter, mean temperature in the hottest quarter, rainfall in the driest month, and rainfall in the hottest quarter were the variables that best explained the climatic niche of the majority of species. The areas of potential species occurrence were reduced by 48.37 % (± 13.63 %) (RCP 4.5) and 62.49 % (± 21.87 %) (RCP 8.5) on average. The potential area of Crinodendron brasilense Reitz & L.B.Sm. decreased the most, by 82.11 % (RCP 4.5) and 90.06 % (RCP 8.5), respectively. High elevation areas in the south of Brazil were identified as priorities for conservation to ensure that climate refuges for high montane forest species are maintained in the future. Climate change events may significantly affect the species evaluated in this study.(AU)


Subject(s)
Climate Change , Forests , Refugium , Brazil , Biodiversity
12.
Theory Biosci ; 141(4): 339-347, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36042123

ABSTRACT

The origin of life was a cosmic event happened on primitive Earth. A critical problem to better understand the origins of life in Earth is the search for chemical scenarios on which the basic building blocks of biological molecules could be produced. Classic works in pre-biotic chemistry frequently considered early Earth as an homogeneous atmosphere constituted by chemical elements such as methane (CH4), ammonia (NH3), water (H2O), hydrogen (H2) and hydrogen sulfide (H2S). Under that scenario, Stanley Miller was capable to produce amino acids and solved the question about the abiotic origin of proteins. Conversely, the origin of nucleic acids has tricked scientists for decades once nucleotides are complex, though necessary molecules to allow the existence of life. Here we review possible chemical scenarios that allowed not only the formation of nucleotides but also other significant biomolecules. We aim to provide a theoretical solution for the origin of biomolecules at specific sites named "Prebiotic Chemical Refugia." Prebiotic chemical refugium should therefore be understood as a geographic site in prebiotic Earth on which certain chemical elements were accumulated in higher proportion than expected, facilitating the production of basic building blocks for biomolecules. This higher proportion should not be understood as static, but dynamic; once the physicochemical conditions of our planet changed periodically. These different concentration of elements, together with geochemical and astronomical changes along days, synodic months and years provided somewhat periodic changes in temperature, pressure, electromagnetic fields, and conditions of humidity, among other features. Recent and classic works suggesting most likely prebiotic refugia on which the main building blocks for biological molecules might be accumulated are reviewed and discussed.


Subject(s)
Origin of Life , Refugium , Earth, Planet , Atmosphere/chemistry , Nucleotides , Evolution, Chemical
13.
PLoS One ; 16(4): e0250022, 2021.
Article in English | MEDLINE | ID: mdl-33831125

ABSTRACT

Populations of migratory waterbirds are facing dramatic declines worldwide due to illegal hunting, habitat loss and climate change. Conservation strategies to reverse these trends are imperative, especially in tropical developing countries, which almost invariably allocate insufficient levels of investment for environmental protection. Here, we compared the effectiveness of sustainable-use Protected Areas (PAs) and Community-based Conservation (CBC) arrangements for the conservation of migratory waterbirds that breed on seasonal riverine sandy beaches in Brazilian Amazonia. We modeled local population responses of four migratory waterbird species on 155 beaches along a ~1,600 km section of a major tributary of the Amazon, as a function of community enforcement, official protection status, human pressure and landscape features. We show that 21 community-protected beaches within the study area host more than 80% of all sampled birds. Black Skimmers showed the most dramatic response, with breeding numbers 135-fold larger in CBC arrangements compared to beaches with no official protection status. The same pattern was observed for nesting Large-Billed and Yellow-Billed Terns. For the Near Threatened Orinoco Goose, PA status was the strongest predictor of local population size. These dramatic results demonstrate the value of protected refugia, achieved through the concerted action of participating local communities, to support breeding populations of key waterbird species. This highly-effective and low-cost conservation model can potentially be replicated in other regions of the developing world experiencing increasingly intensive exploitation of riverine natural resources.


Subject(s)
Charadriiformes/physiology , Community-Based Participatory Research/methods , Conservation of Natural Resources/methods , Animal Migration/physiology , Animals , Biodiversity , Birds , Brazil , Breeding , Charadriiformes/metabolism , Community-Based Participatory Research/trends , Ecosystem , Humans , Population Density , Population Dynamics , Refugium , Seasons , Wetlands
14.
Rev. biol. trop ; Rev. biol. trop;69(1)2021.
Article in Spanish | LILACS, SaludCR | ID: biblio-1507820

ABSTRACT

Introducción: La selección de refugios diurnos es un proceso crucial para los murciélagos debido a su influencia en la ecología, organización social y supervivencia de sus poblaciones. El murciélago narigón (Rhynchonycteris naso) es una especie protegida por leyes de México, cuyos refugios y zonas de forrajeo, están estrictamente asociados a cuerpos de agua, principalmente ríos. Por lo tanto, cambios en la calidad del agua suponen un riesgo para sus poblaciones. Sin embargo, el conocimiento sobre el estado actual de sus poblaciones y refugios diurnos en México, es escaso. Objetivo: Ubicar y describir los refugios diurnos de R. naso y evaluar la relación del tamaño del grupo de murciélagos con las características de los refugios, la salinidad y el pH del agua donde habitan. Métodos: De marzo a octubre 2015, se realizaron búsquedas de refugios diurnos mediante recorridos en lancha a lo largo de ríos, arroyos y lagunas, en once sitios del Área de Protección de Flora y Fauna Laguna de Términos, Campeche México. Por cada refugio localizado se registró el tamaño del grupo y su acomodo en el refugio, el tipo de refugio, el tipo de vegetación, la cobertura, la distancia entre refugios, el diámetro del tronco, la salinidad y el pH. Para investigar el efecto de las variables registradas en los refugios sobre el tamaño de cada grupo, se ajustaron Modelos Lineales Generalizados. Resultados: Encontramos 48 refugios en troncos secos, cortezas de árboles y puentes, asociados a cuerpos de agua dulce y oligohalina, principalmente en vegetación de manglar. El promedio (± EE) del tamaño del grupo fue de 5.3 ± 0.48 para los refugios naturales y de 22.6 ± 9.54 para los artificiales. Encontramos una relación significativa con el tipo de refugio, el tipo de vegetación y el diámetro del tronco. Los refugios con tamaño de grupo mayores presentaron un acomodo agregado. Se localizaron 40 refugios sobre cuerpos de agua dulce y ocho en oligohalina con alto nivel de agrupamiento. Conclusiones: La mayor incidencia de refugios en sitios de agua dulce y ligeramente ácida, es explicada bajo la teoría del óptimo forrajeo. Debido a que el área de estudio se encuentra en el límite de su distribución, el manglar representa el tipo de vegetación más importante para garantizar la permanencia de las poblaciones de R. naso. Adicionalmente, debido a que en algunas porciones de la zona de estudio no fue posible encontrar refugios, es crucial llevar a cabo estudios sobre la calidad del agua y los niveles de contaminación en la región. Este estudio proporciona información relevante sobre las poblaciones del murciélago Rhynchonycteris naso con implicaciones directas sobre su conservación en zonas ribereñas y humedales costeros.


Introduction: The selection of day-roost is a crucial process for bats because it influences the ecology, social organization, and survivorship aspects of their populations. Proboscis bat (Rhynchonycteris naso) is a protected species by Mexican law, whose foraging and roosting areas are strongly associated with bodies of water, primarily rivers. Therefore, alterations in the water quality pose a risk to their populations. However, knowledge of the current state of their populations and roosting ecology is very poor in Mexico. Objectives: To locate and to describe R. naso's diurnal roosts, and to evaluate the relationship of the group size per roost with the characteristics of the diurnal roost, the salinity and pH of the water where they inhabit. Methods: From March to October 2015, we searched diurnal roost through boat tours along rivers, streams, and lagoons, in eleven sites in the Laguna de Términos Flora and Fauna Protection Area, Campeche, Mexico. For each localized roost, we recorded the group size, and their spatial distribution, the type of roost and vegetation, the distance between roosts, the diameter of trunk, the salinity, and pH. In order to investigate the effect of the variables recorded in diurnal roost on size group, generalized linear models were adjusted. Results: We found 48 diurnal roost in dead tree-trunks, tree bark and bridges, associated with freshwater, and oligohaline bodies, mainly in mangrove vegetation. The average size of the groups was 5.3 ± 0.48 and 22.6 ± 9.54 in natural and artificial roosts, respectively. We found a significant relationship with the type of roost, type of vegetation and diameter of trunk. Roosts with larger groups of bats presented an aggregated distribution. We located 40 diurnal roosts on freshwater bodies and eight in oligohaline with a high grouping level. Conclusions: Greater incidence of roost in fresh and lightly acid water is explained under optimal foraging theory. Because the study area is found in the limit of their distribution, mangrove is a very important vegetation type to guarantee the establishment of R. naso populations. Also, due no roosts were found in some portions of the study zone, quality of water, and contaminant level studies are crucial. This study provides relevant information on their populations with direct implications for the conservation in coastal areas.


Subject(s)
Animals , Chiroptera/anatomy & histology , Refugium , Mexico
15.
Rev. biol. trop ; Rev. biol. trop;69(1)2021.
Article in English | LILACS, SaludCR | ID: biblio-1507819

ABSTRACT

Introduction: Migration of people from rural environments to cities has accelerated urbanization and modified the landscape as well as the ecological processes and communities in these areas. The Costa Rican endemic Cabanis´s Ground-Sparrow (Melozone cabanisi) is a species of limited distribution restricted to the "Gran Area Metropolitana", which is the biggest urban settlement of the country. This area has experimented and still experiment an ongoing fragmentation and loss of habitat used by this species (coffee plantations, shrubs, and thickets). Objective: To determine the effects of urbanization on habitat abundance and spatial pattern for the occurrence of Melozone cabanisi. Methods: We modeled the area of potentially suitable habitat for this species in Costa Rica using occurrence and bioclimatic data. Then, we estimated the actual suitable habitat using land cover type layers. Finally, we analyzed the connectivity among the actual suitable habitat patches using single-patch and multi-patch approaches. Results: From the area of potentially suitable habitat estimated by the bioclimatic model, 74 % were urban areas that are unsuitable for Melozone cabanisi. The largest suitable patches within urban areas were coffee plantations; which also were crucial for maintaining connectivity between habitat patches along the species' range. Conclusions: To preserve and protect the Melozone cabanisi, these areas must be taken into consideration by decision-makers in the present and future management plans. We recommend avoiding change shrubs and thickets to urban cover to preserve the occurrence of Melozone cabanisi, and implement a program for the payment of environmental services to landholders, supported by the local governments, to protect those habitats in urban contexts.


Introducción: La migración desde ambientes rurales hacia las ciudades ha incrementado la urbanización. Esto ha modificado el paisaje, así como los procesos ecológicos y comunidades dentro de estas áreas. El Cuatro-ojos de Jupa-roja (Melozone cabanisi) es una especie distribuida principalmente al interior del asentamiento urbano más grande de Costa Rica. Hasta el presente esta área sigue experimentando fragmentación y pérdida del hábitat utilizado por esta especie (plantaciones de café, charrales y tacotales). Objetivo: Determinar los efectos de la urbanización sobre la cantidad de hábitat y su distribución espacial, basada en datos de presencia para M. cabanisi. Métodos: Modelamos el hábitat potencialmente adecuado para M. cabanisi utilizando datos bioclimáticos y de presencia. Luego estimamos el hábitat real utilizando el hábitat potencialmente adecuado y las capas de cobertura del suelo. Finalmente analizamos la conectividad entre los parches de hábitat real utilizando un enfoque multi y mono-parche. Resultados: Del área del hábitat potencialmente adecuado estimada por el modelo bioclimático, 74 % fueron áreas urbanas, lo que consideramos es un porcentaje inadecuado para M. cabanisi. Los parches más grandes de hábitat real dentro de las áreas urbanas fueron plantaciones de café, que a su vez fueron cruciales para mantener la conectividad entre los parches a lo largo del rango de distribución de la especie. Conclusiones: Para conservar y proteger a M. cabanisi, los tomadores de decisiones deben tener en cuenta los charrales, tacotales y cafetales dentro de la distribución de las especies en los planes de gestión presentes y futuros, evitando su cambio a coberturas urbanas.


Subject(s)
Animals , Birds/growth & development , Refugium , Cities , Costa Rica
16.
Am J Bot ; 107(9): 1296-1308, 2020 09.
Article in English | MEDLINE | ID: mdl-33001458

ABSTRACT

PREMISE: Recent phylogeographic work suggests the existence of latitudinal gradients in genetic diversity in northern Mexican plants, but very few studies have examined plants of the Chihuahuan Desert. Tidestromia lanuginosa is a morphologically variable annual species whose distribution includes the Chihuahuan Desert Region. Here we undertook phylogeographic analyses of chloroplast loci in this species to test whether genetic diversity and differentiation of Mexican populations of T. lanuginosa change along a latitudinal gradient and whether diversity is higher in Coahuila, consistent with ideas of lower plant community turnover during the Pleistocene. METHODS: Haplotype network, maximum likelihood tree, and Bayesian phylogenetic haplotype were reconstructed, and genetic diversity was assessed among 26 populations. Barrier analysis was used to explore barriers to gene flow. RESULTS: Four major population groups were identified, corresponding with physiographic provinces in Mexico. Each population group displayed high levels of genetic structure, haplotype, and nucleotide diversity. Diversity was highest in southern populations across the species as a whole and among the Chihuahuan Desert populations. CONCLUSIONS: Tidestromia lanuginosa provides an important example of high phylogeographic and genetic diversity in plants of northern Mexico. Barriers to gene flow among the major population groups have most likely been due to a combination of orographic, climatic, and edaphic variables. The high genetic diversity of T. lanuginosa in southern and central Coahuila is consistent with the hypothesis of full-glacial refugia for arid-adapted plants in this area, and highlights the importance of this region as a center of diversity for the Chihuahuan Desert flora.


Subject(s)
Genetic Variation , Refugium , Bayes Theorem , Mexico , Phylogeny
17.
PLoS One ; 15(9): e0239267, 2020.
Article in English | MEDLINE | ID: mdl-32997690

ABSTRACT

Caribbean Acropora spp. corals have undergone a decline in cover since the second half of the twentieth century. Loss of these architecturally complex and fast-growing corals has resulted in significant, cascading changes to the character, diversity, and available eco-spaces of Caribbean reefs. Few thriving Acropora spp. populations exist today in the Caribbean and western North Atlantic seas, and our limited ability to access data from reefs assessed via long-term monitoring efforts means that reef scientists are challenged to determine resilience and longevity of existing Acropora spp. reefs. Here we used multiple dating methods to measure reef longevity and determine whether Coral Gardens Reef, Belize, is a refuge for Acropora cervicornis against the backdrop of wider Caribbean decline. We used a new genetic-aging technique to identify sample sites, and radiocarbon and high-precision uranium-thorium (U-Th) dating techniques to test whether one of the largest populations of extant A. cervicornis in the western Caribbean is newly established after the 1980s, or represents a longer-lived, stable population. We did so with respect for ethical sampling of a threatened species. Our data show corals ranging in age from 1910 (14C) or 1915 (230Th) to at least November 2019. While we cannot exclude the possibility of short gaps in the residence of A. cervicornis earlier in the record, the data show consistent and sustained living coral throughout the 1980s and up to at least 2019. We suggest that Coral Gardens has served as a refuge for A. cervicornis and that identifying other, similar sites may be critical to efforts to grow, preserve, conserve, and seed besieged Caribbean reefs.


Subject(s)
Anthozoa/physiology , Conservation of Natural Resources , Coral Reefs , Refugium , Animals , Belize , Caribbean Region , Endangered Species , Population Dynamics
18.
Neotrop Entomol ; 49(6): 806-811, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32809137

ABSTRACT

Stink bugs (Pentatomidae) are among the main entomological problems in the international farming. Their ability in using alternative plants (refuges) during the off-season is one of the reasons that led them to the status of key pests in several crops. Like other insect species, stink bugs are subject to atmospheric variations. Therefore, the objective of this experiment was to evaluate the abundance, the co-occurrence, and its variations according to the weather in the off-season. The work was conducted between 2014 and 2018, in the municipality of Cruz Alta, state of Rio Grande do Sul (RS), Brazil. Every year, refuges formed by Poaceae and located around the cropped area were evaluated in the second fortnight of June, corresponding to the beginning of the winter solstice. Atmospheric variables corresponding to the evaluation period were used to explain the variation in the populations. In short, our results demonstrated interannual variations in the population abundance of stink bugs in the evaluated refuges. We also found variations in the co-occurrence between species. Finally, we demonstrate the trend in the increase in these refuges in years with cold and dry off-seasons.


Subject(s)
Atmosphere , Heteroptera , Weather , Animals , Brazil , Crops, Agricultural , Refugium , Seasons , Glycine max
19.
Conserv Biol ; 34(2): 405-415, 2020 04.
Article in English | MEDLINE | ID: mdl-31773785

ABSTRACT

Terrestrial animals are negatively affected by habitat loss, which is assessed on a landscape scale, whereas secondary effects of habitat loss, such as crowding, are usually disregarded. Such impacts are inherently hard to address and poorly understood, and there is a growing concern that they could have dire consequences. We sampled birds throughout a deforestation process to assess crowding stress in an adjacent habitat remnant in the southern Brazilian Atlantic Forest. Crowding is expected of highly mobile taxa, especially given the microhabitat heterogeneity of Neotropical forests, and we hypothesized that the arrival of new individuals or species in refuges shifts assemblage patterns. We used point counts to obtain bird abundances in a before-after-control-impact design sampling of a deforestation event. Temporal changes in taxonomic and functional diversity were examined with metrics used to assess alpha and beta diversity, turnover of taxonomic and functional similarity, and taxonomic and functional composition. Over time increased abundance of some species altered the Simpson index and affected the abundance-distribution of traits in the habitat remnant. Taxonomic composition and functional composition changed in the remnant, and thus bird assemblages changed over time. Taxonomic and functional metrics indicated that fugitives affected resident assemblages in refuges, and effects endured >2 years after the deforestation processes had ceased. Dissimilarity of taxonomic composition between pre- and postdeforestation assemblages increased, whereas functional composition reverted to preimpact conditions. We found that ecological disruptions resulted from crowding and escalated into disruptions of species' assemblages and potentially compromising ecosystem functioning. It is important to consider crowding effects of highly mobile taxa during impact assessments, especially in large-scale infrastructure projects that may affect larger areas than is assumed.


Efectos del Amontonamiento debido a la Pérdida del Hábitat sobre los Patrones de Ensamblaje de las Especies Resumen Los animales terrestres se ven afectados negativamente por la pérdida del hábitat, la cual es evaluada con una escala de paisaje, mientras que los efectos secundarios de la pérdida del hábitat, como el amontonamiento, suelen ser ignorados. Dichos impactos son inherentemente difíciles de tratar y su entendimiento es muy pobre, además de que existe una preocupación creciente por las posibles consecuencias graves que podrían tener. Muestreamos aves durante un proceso de deforestación para evaluar el estrés por amontonamiento en un hábitat remanente contiguo a la parte sur del Bosque Atlántico Brasileño. Se espera que el amontonamiento ocurra en taxones con mucha movilidad, especialmente en el caso de los heterogéneos bosques Neotropicales, por lo que nuestra hipótesis consistió en suponer que la llegada a los refugios de nuevos individuos o especies modifica los patrones de ensamblado. Usamos el conteo por puntos para obtener la abundancia de las aves en un diseño de muestreo de antes-después-control-impacto de un evento de deforestación. Examinamos los cambios temporales en la diversidad taxonómica y funcional con medidas usadas para evaluar la diversidad alfa y beta, la rotación de la similitud taxonómica y funcional y la composición taxonómica y funcional. Con el tiempo, el incremento en la abundancia de algunas especies alteró el índice Simpson y afectó la abundancia y distribución de los caracteres en el hábitat remanente. La composición taxonómica y la composición funcional cambiaron en el hábitat remanente, por lo que los ensamblajes de aves cambiaron con el tiempo. Las medidas taxonómicas y funcionales indicaron que los individuos fugitivos afectaron a los ensamblajes de residentes en los refugios y sus efectos perduraron más de dos años después de que el proceso de deforestación había culminado. La disparidad de la composición taxonómica entre los ensamblajes antes y después de la deforestación incrementó, mientras que la composición funcional se revirtió a las condiciones previas al impacto. Encontramos que las perturbaciones ecológicas resultaron en el amontonamiento de especies y después escalaron hasta llegar a ser perturbaciones en el ensamblaje de las especies y potencial empobrecimiento del funcionamiento del ecosistema. Es importante considerar los efectos del amontonamiento de los taxones con mucha movilidad durante las evaluaciones de impacto ambiental, especialmente para proyectos con infraestructuras a gran escala que podrían afectar a un área mayor a la supuesta inicialmente.


Subject(s)
Biodiversity , Ecosystem , Animals , Brazil , Conservation of Natural Resources , Forests
20.
PLoS One ; 14(5): e0211171, 2019.
Article in English | MEDLINE | ID: mdl-31112555

ABSTRACT

Climate and environmental conditions are determinant for coral distribution and their very existence. When changes in such conditions occur, their effects on distribution can be predicted through species distribution models, anticipating suitable habitats for the subsistence of species. Mussismilia harttii is one of the most endangered Brazilian endemic reef-building corals, and in increasing risk of extinction. Herein, species distribution models were used to determine the present and future potential habitats for M. harttii. Estimations were made through the maximum entropy approach, predicting suitable habitat losses and gains by the end of the 21st century. For this purpose, species records published in the last 20 years and current and future environmental variables were correlated. The best models were chosen according to the Akaike information criterion (AIC) and evaluated through the partial ROC (AUCratio), a new approach which uses independent occurrence data. Both approaches showed that the models performed satisfactorily in predicting potential habitat areas for the species. Future projections were made using the International Panel on Climate Change (IPCC) scenarios for 2100, with different levels of greenhouse gas emission. Representative Concentration Pathways (RCPs) were used to model the Future Potential Habitat (FPH) of M. harttii in two different scenarios: stabilization of emissions (RCP 4.5) and increase of emissions (RCP 8.5). According to the results, shallow waters to the south of the study area concentrate most of the current potential habitats for the species. However, in future scenarios, there was a loss of suitable areas in relation to the Current Potential Habitat (RCP 4.5 46% and RCP 8.5 59%), whereas there is a southward shift of the suitable areas. In all scenarios of FPH, the temperature was the variable with the greatest contribution to the models (> 35%), followed by the current velocity (> 33%) and bathymetry (>29%). In contrast, there is an increase of deep (50-75 m) suitable areas FPH scenarios, mainly in the southern portion of its distribution, at Abrolhos Bank (off Espirito Santo State). These deeper sites might serve as refugia for the species in global warming scenarios. Coral communities at such depths would be less susceptible to impacts of climate change on temperature and salinity. However, the deep sea is not free from human impacts and measures to protect deeper ecosystems should be prioritized in environmental policies for Brazilian marine conservation, especially the Abrolhos Bank, due to its importance for M. harttii.


Subject(s)
Anthozoa , Climate Change , Ecosystem , Endangered Species , Animals , Area Under Curve , Brazil , Coral Reefs , Geography , Global Warming , Models, Theoretical , ROC Curve , Refugium
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