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Climate temporality is a phenomenon that affects species activity and distribution patterns across spatial and temporal scales. Despite the global availability of microclimatic data, their use to predict activity patterns and distributions remains scarce, particularly at fine temporal scales (e.g. < month). Predicting activity patterns based on climatic data may allow us to foresee some of the consequences of climate change, particularly for ectothermic vertebrates. The Gila monster exhibits marked daily and seasonal activity patterns linked to physiology and reproduction. Here we evaluate whether ecological niche models fitted using microclimate data can predict temporal activity patterns using the Gila monster Heloderma suspectum as a study system. Furthermore, we identified whether the activity patterns are related to physiological constraints. We used dated occurrences from museum specimens and human observations to generate and test ecological niche models using minimum volume ellipsoids. We generated hourly microclimatic data for each occurrence site for 10 years using the NicheMapR package. For ecological niche modelling, we compared the traditional seasonal approach versus a daily activity pattern strategy for model construction. We tested both using the omission rate of independent observations (citizen science data). Finally, we tested whether unimodal and bimodal activity patterns for each season could be recreated through ecological niche modelling and whether these patterns followed known physiological constraints. The unimodal and bimodal activity patterns previously reported directly from tracking individuals across the year were recovered using niche modelling and microclimate across the species' geographical range. We found that upper thermal tolerances can explain the daily activity patterns of this species. We conclude that ecological niche models trained with microclimatic data can be used to predict activity patterns at high temporal resolutions, particularly on ectotherm species of arid zones coping with rapid climate modifications. Furthermore, the use of high temporal resolution variables can lead to a better niche delimitation, enhancing the results of any research objective that uses correlative models.

La estacionalidad climática es un fenómeno que afecta la actividad de las especies y los patrones de distribución a diferentes escalas espaciales y temporales. A pesar de la disponibilidad global de datos microclimáticos para estudiar dichos patrones, su uso sigue siendo escaso, particularmente en escalas temporales finas (e.g., < mes). La predicción de patrones de actividad basados en datos climáticos puede permitirnos prever algunas de las potenciales consecuencias del cambio climático, particularmente para los vertebrados ectotérmicos. El monstruo de Gila (Heloderma suspectum) exhibe marcados patrones de actividad diarios y estacionales vinculados a la fisiología y la reproducción. En este trabajo evaluamos cómo los modelos de nichos ecológicos ajustados con datos de microclima, pueden predecir patrones de actividad temporal, utilizando al monstruo de Gila como sistema de estudio. Además, identificamos si los patrones de actividad están relacionados con restricciones fisiológicas. Usamos registros de presencia provenientes de colecciones científicas y de ciencia ciudadana para generar y probar modelos de nichos ecológicos usando elipsoides de volumen mínimo. Generamos datos microclimáticos para cada hora en cada sitio de presencia durante diez años utilizando el paquete NicheMapR. Para el modelado de nichos ecológicos, comparamos el enfoque estacional tradicional con una estrategia de patrón de actividad diaria para la construcción del nicho. Ambos enfoques fueron probados utilizando la tasa de omisión de observaciones independientes (provenientes de datos de ciencia ciudadana). Finalmente, probamos si los patrones de actividad unimodales y bimodales para cada estación podían recrearse a través de modelos de nichos ecológicos y si estos patrones seguían restricciones fisiológicas conocidas. Los patrones de actividad unimodal y bimodal previamente informados directamente del seguimiento de individuos a lo largo del año, sí se recuperaron mediante el uso de modelos de nicho y microclimas en todo el rango geográfico de la especie. Encontramos también que las tolerancias térmicas superiores pueden explicar los patrones de actividad diaria de esta especie. Concluimos que los modelos de nichos ecológicos entrenados con datos microclimáticos pueden usarse para predecir patrones de actividad en altas resoluciones temporales, particularmente en especies ectotermas de zonas áridas que se enfrentan a modificaciones climáticas rápidas. Además, consideramos que el uso de variables con alta resolución temporal puede conducir a una mejor delimitación de nichos, mejorando los resultados de cualquier objetivo de investigación que utilice estos modelos correlativos.

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Enceladus is a potential target for future astrobiological missions. NASA's Cassini spacecraft demonstrated that the Saturnian moon harbors a salty ocean beneath its icy crust and the existence and analysis of the plume suggest water-rock reactions, consistent with the possible presence of hydrothermal vents. Particularly, the plume analysis revealed the presence of molecular hydrogen, which may be used as an energy source by microorganisms ( e.g., methanogens). This could support the possibility that populations of methanogens could establish in such environments if they exist on Enceladus. We took a macroscale approximation using ecological niche modeling to evaluate whether conditions suitable for methanogenic archaea on Earth are expected in Enceladus. In addition, we employed a new approach for computing the biomass using the Monod growth model. The response curves for the environmental variables performed well statistically, indicating that simple correlative models may be used to approximate large-scale distributions of these genera on Earth. We found that the potential hydrothermal conditions on Enceladus fit within the macroscale conditions identified as suitable for methanogens on Earth, and estimated a concentration of 1010-1011 cells/cm3.

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A fascinating pattern in nature is the uneven distribution of biodiversity among clades, some with low species richness and phenotypic variation in contrast to others with remarkable species richness and phenotypic diversity. In animals, communication signals are crucial for intra- and interspecific interactions and are likely an important factor in speciation. However, evidence for the association between the evolution of such signals and speciation is mixed. In hummingbirds, plumage coloration is an important communication signal, particularly for mate selection. Here, using reflectance data for 237 hummingbird species (∼66% of total diversity), we demonstrate that color evolution rates are associated with speciation rates, and that differences among feather patches are consistent with an interplay between natural and sexual selection. We found that female color evolution rates of multiple plumage elements, including the gorget, were similar to those of males. Although male color evolution in this patch was associated with speciation, female gorget color evolution was not. In other patches, the relationship between speciation and color evolution rates was pervasive between sexes. We anticipate that future studies on animal communication will likely find that evolution of signaling traits of both sexes has played a vital role in generating signal and species diversity.

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Ecological niche models (ENMs) aim to recreate the relationships between species and the environments where they occur and allow us to identify unexplored areas in geography where these species might be present. These models have been successfully used in terrestrial organisms but their application in aquatic organisms is still scarce. Recent advances in the availability of species occurrences and environmental information particular to aquatic systems allow the evaluation of these models. This study aims to characterize the niche of the Sabaleta Brycon henni Eigenmann 1913, an endemic fish of the Colombian Andes, using ENMs to predict its geographical distribution across the Magdalena Basin. For this purpose, we used a set of environmental variables specific to freshwater systems in addition to the customary bioclimatic variables, and species' occurrence data to model its potential distribution using the Maximum Entropy algorithm (MaxEnt). We evaluate the relative importance between these two sets of variables, the model's performance, and its geographic overlap with the IUCN map. Both on-site (annual precipitation, minimum temperature of coldest month) and upstream variables (open waters, average minimum temperature of the coldest month and average precipitation seasonality) were included in the models with the highest predictive accuracy. With an area under the curve of 90%, 99% of the species occurrences and 68% of absences correctly predicted, our results support the good performance of ENMs to predict the potential distribution of the Sabaleta and the utility of this tool in conservation and decision-making at the national level.

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The male Anna's hummingbird features a brightly reddish-pink reflecting gorget, due to large stacks of melanosomes in the feather barbules, arranged in layers separated by keratin. Direct observations together with detailed scatterometry demonstrated that the barbules reflect incident light in an approximately specular manner. The structural colouration is iridescent, i.e. varies with a changing angle of light incidence. Spectrophotometrical measurements of the barbule reflectance and absorbance can be well interpreted with calculated spectra obtained with a transfer matrix method for optical multilayers, using anatomical data and measured refractive index spectra. The organization of the reflectors as a Venetian blind presumably functions to create a high spectral contrast of the male's plumage during courtship.

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Colombia is the country with the highest bird diversity in the world. Despite active research in ornithology, compelling morphological information of most bird species is still sparse. However, morphological information is the baseline to understand how species respond to environmental variation and how ecosystems respond to species loss. As part of a national initiative, the Instituto Alexander von Humboldt in collaboration with 12 Colombian institutions and seven biological collections, measured up to 15 morphological traits of 9,892 individuals corresponding to 606 species: 3,492 from individuals captured in field and 6,400 from museum specimens. Species measured are mainly distributed in high Andean forest, páramo, and wetland ecosystems. Seven ornithological collections in Colombia and 18 páramo complexes throughout Colombia were visited from 2013 to 2015. The morphological traits involved measurements from bill (total and exposed culmen, bill width and depth), wing (length, area, wingspan, and the distance between longest primary and longest secondary), tail (length and shape), tarsus (length), hallux (length and claw hallux), and mass. The number of measured specimens per species was variable, ranging from 1 to 321 individuals with a median of four individuals per species. Overall, this database gathered morphological information for >30% of Colombian bird diversity. No copyright, proprietary, or cost restrictions apply; the data should be cited appropriately when used.

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Rapid transformation of natural ecosystems changes ecological conditions for important human disease vector species; therefore, an essential task is to identify and understand the variables that shape distributions of these species to optimize efforts toward control and mitigation. Ecological niche modeling was used to estimate the potential distribution and to assess hypotheses of niche similarity among the three main malaria vector species in northern Colombia: Anopheles nuneztovari, An. albimanus, and An. darlingi. Georeferenced point collection data and remotely sensed, fine-resolution satellite imagery were integrated across the Urabá -Bajo Cauca-Alto Sinú malaria endemic area using a maximum entropy algorithm. Results showed that An. nuneztovari has the widest geographic distribution, occupying almost the entire study region; this niche breadth is probably related to the ability of this species to colonize both, natural and disturbed environments. The model for An. darlingi showed that most suitable localities for this species in Bajo Cauca were along the Cauca and Nechí river. The riparian ecosystems in this region and the potential for rapid adaptation by this species to novel environments, may favor the establishment of populations of this species. Apparently, the three main Colombian Anopheles vector species in this endemic area do not occupy environments either with high seasonality, or with low seasonality and high NDVI values. Estimated overlap in geographic space between An. nuneztovari and An. albimanus indicated broad spatial and environmental similarity between these species. An. nuneztovari has a broader niche and potential distribution. Dispersal ability of these species and their ability to occupy diverse environmental situations may facilitate sympatry across many environmental and geographic contexts. These model results may be useful for the design and implementation of malaria species-specific vector control interventions optimized for this important malaria region.

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A persistent challenge in ecology is to tease apart the influence of multiple processes acting simultaneously and interacting in complex ways to shape the structure of species assemblages. We implement a heuristic approach that relies on explicitly defining species pools and permits assessment of the relative influence of the main processes thought to shape assemblage structure: environmental filtering, dispersal limitations, and biotic interactions. We illustrate our approach using data on the assemblage composition and geographic distribution of hummingbirds, a comprehensive phylogeny and morphological traits. The implementation of several process-based species pool definitions in null models suggests that temperature-but not precipitation or dispersal limitation-acts as the main regional filter of assemblage structure. Incorporating this environmental filter directly into the definition of assemblage-specific species pools revealed an otherwise hidden pattern of phylogenetic evenness, indicating that biotic interactions might further influence hummingbird assemblage structure. Such hidden patterns of assemblage structure call for a reexamination of a multitude of phylogenetic- and trait-based studies that did not explicitly consider potentially important processes in their definition of the species pool. Our heuristic approach provides a transparent way to explore patterns and refine interpretations of the underlying causes of assemblage structure.

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Patterns of phylogenetic structure of assemblages are increasingly used to gain insight into the ecological and evolutionary processes involved in the assembly of co-occurring species. Metrics of phylogenetic structure can be sensitive to scaling issues and data availability. Here we empirically assess the sensitivity of four metrics of phylogenetic structure of assemblages to changes in (i) the source of data, (ii) the spatial grain at which assemblages are defined, and (iii) the definition of species pools using hummingbird (Trochilidae) assemblages along an elevational gradient in Colombia. We also discuss some of the implications in terms of the potential mechanisms driving these patterns. To explore how source of data influence phylogenetic structure we defined assemblages using three sources of data: field inventories, museum specimens, and range maps. Assemblages were defined at two spatial grains: coarse-grained (elevational bands of 800-m width) and fine-grained (1-km(2) plots). We used three different species pools: all species contained in assemblages, all species within half-degree quadrats, and all species either above or below 2000 m elevation. Metrics considering phylogenetic relationships among all species within assemblages showed phylogenetic clustering at high elevations and phylogenetic evenness in the lowlands, whereas those metrics considering only the closest co-occurring relatives showed the opposite trend. This result suggests that using multiple metrics of phylogenetic structure should provide greater insight into the mechanisms shaping assemblage structure. The source and spatial grain of data had important influences on estimates of both richness and phylogenetic structure. Metrics considering the co-occurrence of close relatives were particularly sensitive to changes in the spatial grain. Assemblages based on range maps included more species and showed less phylogenetic structure than assemblages based on museum or field inventories. Coarse-grained assemblages included more distantly related species and thus showed a more even phylogenetic structure than fine-grained assemblages. Our results emphasize the importance of carefully selecting the scale, source of data and metric used in analysis of the phylogenetic structure of assemblages.

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An important challenge in community ecology is to determine how processes occurring at multiple spatial, temporal, and phylogenetic scales influence the structure of local communities. While indexes of phylogenetic structure, which measure how related species are in a community, provide insight into the processes that shape species coexistence, they fail to pinpoint the phylogenetic scales at which those processes occur. Here, we explore a framework to identify the species and clades responsible for the inferred patterns of phylogenetic structure within a given community. Further, we evaluate how communities that share the nonrandom representation of species from a given clade in the phylogeny are distributed across geography and environmental gradients. Using Ecuadorian hummingbird communities, we found that multiple patterns of phylogenetic structure often occur within a local assemblage. We also identified four geographic regions where species from certain clades exhibit nonrandom representation: the eastern Amazonian lowlands, the western dry lowlands, the Andes at middle elevations, and the Andes at high elevations. The environmental gradients along which changes in the local coexistence of species occurred were mainly elevation, annual precipitation, and seasonality in both temperature and precipitation. Finally, we show how these patterns can be used to generate hypotheses about the processes that allow species coexistence.

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