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The longstanding view of Neotropical mountain uplift as a promoter of species diversification has become commonplace in the last decades and could benefit from more specific Earth-Life evolution associations. We now know that mountain formation has contributed to the outstanding levels of richness and endemism of Neotropical mountains. Nonetheless, we are lacking conceptual and empirical frameworks where geological and biological processes are causally linked through testable hypotheses. In this perspective, we present volcanic activity in the Neotropics, not as phenomena occurring “on top of” mountain uplift, the latter being the phenomena of biogeographical interest, but rather as geological processes that directly impact biodiversity and are themselves the phenomenon of biogeographical interest. Volcanoes deserve biogeographical attention because their effects on landscape evolution generate predictable biodiversity process counterparts that can be integrated into biogeographical models enabling hypothesis testing. We review examples in the literature emphasizing the spatio-temporal scale of volcanism’s predicted and recorded effects on biodiversity. We illustrate our perspective by two recent study cases, focusing on wax palms and passerine birds. In the first one, wax palm genomic sampling was used to test 2 hypotheses: that the northern Andes have been disconnected in the past and connected by rapid but repeated eruptions of caldera-forming eruptions in the Colombian Massif fostering episodic dispersal, or alternatively, that they have always been continuous and have gradually uplifted hosting continuous diversification and dispersal through time. In broadly this same area, genetic and phenotypic data revealed the existence of a hybrid zone between species in the warbler genus Myioborus. Because hybridization is likely younger than volcanic activity, topographic connection spurred by volcanism could have also enabled secondary contact between previously isolated species, a hypothesis that merits formal testing. Altogether, we emphasize the pertinence of the volcanic record in offering opportunities for the evaluation of biogeographical hypotheses in the context of Neotropical mountains and their singularly outsized biodiversity.

High-resolution absorption spectroscopy toward bright background sources has had a paramount role in understanding early galaxy formation, the evolution of the intergalactic medium and the reionisation of the Universe. However, these studies are now approaching the boundaries of what can be achieved at ground-based 8-10m class telescopes. The identification of primeval systems at the highest redshifts, within the reionisation epoch and even into the dark ages, and of the products of the first generation of stars and the chemical enrichment of the early Universe, requires observing very faint targets with a signal-to-noise ratio high enough to detect very weak spectral signatures. In this paper, we describe the giant leap forward that will be enabled by ANDES, the high-resolution spectrograph for the ELT, in these key science fields, together with a brief, non-exhaustive overview of other extragalactic research topics that will be pursued by this instrument, and its synergistic use with other facilities that will become available in the early 2030s. [ABSTRACT FROM AUTHOR]

A new species in the rubbernose catfish genus Chaetostoma is described from the Aguaytia, Pisqui and Palcazu Rivers, which drain the Pampa de Sacramento Region in the Ucayali River drainage of central Peru. The new species is distinguished from congeners, except C. anomalum, C. branickii, C. dorsale, C. leucomelas, C. microps, C. nudirostre, C. palmeri and C. thomsoni by having distinct, white, variably-shaped spots or vermiculations ½–2× nostril diameter on dark grey to black background on the head (vs. spots absent or black on light-coloured background). The new species is distinguished from C. anomalum, C. branickii, C. dorsale, C. microps, C. nudirostre and C. thomsoni by having highly variable, distinct white spots, vermiculations or bands ½–10× nostril diameter on the body, from C. leucomelas by having dorsal and caudal fin indistinctly and variably-patterned with zero to four bands (vs. dorsal and caudal fin consistently having five or more uniform bands) and from C. palmeri by having two predorsal plates (vs. three), supraoccipital excrescence present (vs. absent) and pelvic-fin insertion slightly posterior to dorsal-fin insertion (vs. pelvic-fin insertion at middle of dorsal-fin base). Species delimitation analyses of the COI and Cytb genes further support the recognition of this new species. [ABSTRACT FROM AUTHOR]

Aim: Mycorrhizal fungi play key roles in the functioning of terrestrial ecosystems. The main types of mycorrhizal associations are arbuscular mycorrhizae, ectomycorrhizae, ericoid mycorrhizae and orchid mycorrhizae. Previous studies have shown that the abundance of plants with different types of mycorrhizal associations change gradually along latitudinal and altitudinal gradients driven by the effects of climate and soil nutrients. We aimed to understand how altitude and climatic and soil variables shape the distribution patterns of tropical plant mycorrhizal types and nitrogen‐fixing plants along altitudinal gradients in the Andes. Location: Colombian Andean mountain range. Time Period: Present day. Major Taxa Studied: Plants (vascular and non‐vascular). Methods: We used a herbarium plant records database and assigned mycorrhizal type to each plant species based on the available literature. Bioclimatic and soil variables were also compiled at a resolution of 10 km. We calculated the proportion of each mycorrhizal association type per grid cell and created a diversity index to explore their spatial distribution and association with abiotic factors based on LMs. Results: The diversity of mycorrhizal associations increased with altitude and peaked around 3000 m, in an ecotone belt known as the subpáramo recognised by the high abundance of Ericaceae species. Soil carbon stock and soil total nitrogen were also positively correlated with the diversity of mycorrhizal types. Moreover, the abundance of arbuscular mycorrhizal plants was highest at low elevations and increased with the proportion of nitrogen‐fixing plants per cell. Main Conclusions: Our results indicate that mycorrhizal associations gradually change along altitudinal gradients in the tropical Andes. Climatic factors and the interactions between climatic and edaphic factors have the greatest explanatory power to predict the distribution of types of mycorrhizal associations along the altitudinal gradient. Based on these results we expect that climate change could potentially alter the distribution of mycorrhizal types in tropical mountains with unknown consequences for ecosystem functions. [ABSTRACT FROM AUTHOR]

This paper presents the results of archaeological investigations within funerary contexts at the site of Marcajirca (a.d. 1000–1600) in the north-central highlands of Peru. The results suggest the existence of various population groups, or ayllu members, that were buried at this site. Two contemporary types of tombs are predominant, funerary caves and chullpas, along with two belowground tombs, which are atypical in the region. Bioarchaeological analyses indicate that all the tombs were collective and that the remains were manipulated over time. The evidence from Marcajirca points to important changes in funerary patterns with respect to the previous period, including tombs being incorporated into residential places and, later in time, tombs as created, extra, private spaces by enclosing the chullpas within patios where rituals such as burning of offerings were practiced. The results are discussed within the context of the cult of the dead and the formation of ayllus. [ABSTRACT FROM AUTHOR]

We report a tephra deposit in the southern Lake Titicaca Basin, Bolivia, which was deposited by a major, previously unrecognized eruption sometime between AD 400 and 720. Archaeological data suggest these centuries were characterized by a substantial community migration to Tiwanaku, where social interaction networks gave birth to one of the Andes' first large complex societies. Here we provide an initial characterization of this tephra, based on samples from the archaeological site Khonkho Wankane. The same tephra is present at two other archaeological sites in the region. Given the great distance to the nearest active volcano, this tephra layer likely derives from a large-magnitude, Late-Holocene explosive eruption of a Central Andean volcano. We suggest that this major event be included in the human history of the region, given its inferred magnitude and wide dispersal area. Future research could confirm the Khonkho tephra at other sites, identify the source volcano, estimate its volume, and more precisely date the eruption. [ABSTRACT FROM AUTHOR]

Genesis of Phanerozoic Andean andesite rocks is related to the subduction of the oceanic Nazca plate beneath the South American continental plate along the west coast of South America. Exploratory data analytics is done on whole-rock geochemical data of 3311 andesite rock samples collected from the Andes orogenic belt, extending from Argentina, Chile, Bolivia, Peru, and Ecuador to Colombia. Python programming has been used for the visualisation and interpretation of large volumes of geochemical data, and data-driven tectonomagmatic inferences for volcanism extending across the South American continent have been drawn with the help of data analytics. Interelemental diagrams with Zr as a fractionation index reveal relative immobility and incompatibility of several major elements, large ion lithophile elements, high field strength elements, and rare earth elements. The interelemental diagrams, correlation matrix and heat maps drawn for major elements reveal that except K2O, TiO2 and SiO2, all major elements decrease with fractionation. Major element variation trends indicate that plagioclase and pyroxene were the major fractionating phases. The density plots give insight into the range of variation and data density of major and trace elements. Petrogenetic study reveals calc-alkaline, basaltic andesite to andesite, and back-arc tectonomagmatic environment for these volcanic rocks. Mantle source of Andean magma was enriched to primitive upper mantle. Around 25–30% partial melting of the upper mantle led to the genesis of the most primitive Andean magma. [ABSTRACT FROM AUTHOR]

Context: The tropical Andes have a long history of human land use, which has affected vegetation patterns especially at high elevations. However, reference patterns to quantify these effects are missing due to lacking data from mountain ranges unaffected by humans. Objectives: We compared landscape-scale patterns of forest distribution in the largest tropical Andean mountain range without high-elevation human occupancy, the Cordillera de Vilcabamba, and a nearby range with a long land-use history, the Cordillera de San Miguel, in Peru. Methods: We quantified topographical positions (exposition, slope, wetness index) of 12.5 × 12.5-m2 pixels with and without forest cover in 100-m elevational bands and compared the study regions. Results: In the undisturbed range (Vilcabamba), forest consistently occurred on steeper slopes than non-forest, differing little in other topographic metrics except a slight preference for the less sunny South- and West-facing slopes. In the disturbed range (San Miguel), forest showed little preference for any landscape position at elevations below 3500 m, but at higher elevations patterns were very clear: forest was more restricted to valley bottoms, as indicated consistently by higher topographic wetness and lower slope and topographic position indices, and to the less sunny South-facing slopes. Conclusions: Land-use has a strong influence on landscape-level forest distribution in this part of the tropical Andes. Similar effects are likely in other tropical mountains, although no reference areas are available in most of them. The patterns described here can support the use of remote sensing to detect minimally disturbed tropical alpine-treeline ecotones, which should be focal points for conservation and research. [ABSTRACT FROM AUTHOR]

In the Andes, the complex topography and unique latitudinal extension of the cordillera are responsible for a wide diversity of climate gradients and contrasts. Part I of this series reviews the current modeling efforts in simulating key atmospheric-orographic processes for the weather and climate of the Andean region. Building on this foundation, Part II focuses on global and regional climate models challenging task of correctly simulating changes in surface-atmosphere interactions and hydroclimate processes to provide reliable future projections of hydroclimatic trajectories in the Andes Cordillera. We provide a review of recent advances in atmospheric modeling to identify and produce reliable hydroclimate information in the Andes. In particular, we summarize the most recent modeling research on projected changes by the end of the 21st century in terms of temperature and precipitation over the Andes, the mountain elevation-dependent warming signal, and land cover changes. Recent improvements made in atmospheric kilometer-scale model configurations (e.g., resolution, parameterizations and surface forcing data) are briefly reviewed, highlighting their impact on modeling results in the Andes for precipitation, atmospheric and surface-atmosphere interaction processes, as mentioned in recent studies. Finally, we discuss the challenges and perspectives of climate modeling, with a focus on the hydroclimate of the Andes. [ABSTRACT FROM AUTHOR]

The Andes is the longest mountain range in the world, stretching from tropical South America to austral Patagonia (12°N-55°S). Along with the climate differences associated with latitude, the Andean region also features contrasting slopes and elevations, reaching altitudes of more than 4,000 m. a.s.l., in a relatively narrow crosswise section, and hosts diverse ecosystems and human settlements. This complex landscape poses a great challenge to weather and climate simulations. The interaction of the topography with the large-scale atmospheric motions controls meteorological phenomena at scales of a few kilometers, often inadequately represented in global (grid spacing ∼200–50 km) and regional (∼50–25 km) climate simulations previously studied for the Andes. These simulations typically exhibit large biases in precipitation, wind and near-surface temperature over the Andes, and they are not suited to represent strong gradients associated with the regional processes. In recent years (∼2010–2024), a number of modeling studies, including convection permitting simulations, have contributed to our understanding of the characteristics and distribution of a variety of systems and processes along the Andes, including orographic precipitation, precipitation hotspots, mountain circulations, gravity waves, among others. This is Part I of a two-part review about atmospheric modeling over the Andes. In Part I we review the current strengths and limitations of numerical modeling in simulating key atmospheric-orographic processes for the weather and climate of the Andean region, including low-level jets, downslope winds, gravity waves, and orographic precipitation, among others. In Part II, we review how climate models simulate surface-atmosphere interactions and hydroclimate processes in the Andes Cordillera to offer information on projections for land-cover/land-use change or climate change. With a focus on the hydroclimate, we also address some of the main challenges in numerical modeling for the region. [ABSTRACT FROM AUTHOR]

Globally, there is a significant trend in the loss of native forests, including those of the Polylepis genus, which are essential for soil conservation across the Andes Mountain range. These forests play a critical role in regulating water flow, promoting soil regeneration, and retaining essential nutrients and sediments, thereby contributing to the soil conservation of the region. In Ecuador, these forests are often fragmented and isolated in areas of high cloud cover, making it difficult to use remote sensing and spectral vegetation indices to detect this forest species. This study developed twelve scenarios using medium- and high-resolution satellite data, integrating datasets such as Sentinel-2 and PlanetScope (optical), Sentinel-1 (radar), and the Sigtierras project topographic data. The scenarios were categorized into two groups: SC1–SC6, combining 5 m resolution data, and SC7–SC12, combining 10 m resolution data. Additionally, each scenario was tested with two target types: multiclass (distinguishing Polylepis stands, native forest, Pine, Shrub vegetation, and other classes) and binary (distinguishing Polylepis from non-Polylepis). The Recursive Feature Elimination technique was employed to identify the most effective variables for each scenario. This process reduced the number of variables by selecting those with high importance according to a Random Forest model, using accuracy and Kappa values as criteria. Finally, the scenario that presented the highest reliability was SC10 (Sentinel-2 and Topography) with a pixel size of 10 m in a multiclass target, achieving an accuracy of 0.91 and a Kappa coefficient of 0.80. For the Polylepis class, the User Accuracy and Producer Accuracy were 0.90 and 0.89, respectively. The findings confirm that, despite the limited area of the Polylepis stands, integrating topographic and spectral variables at a 10 m pixel resolution improves detection accuracy. [ABSTRACT FROM AUTHOR]

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. The diet of these mice 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"). Mice may also 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 summit of Volcán Llullaillaco (6739 m) revealed 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 from 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 they may occur at higher elevations beneath the snowpack or in other cryptic microhabitats. [ABSTRACT FROM AUTHOR]

The northern Andes of southern Colombia contain a rich geologic history recorded by Proterozoic to Cenozoic metamorphic, igneous, and sedimentary rocks. The region plays a pivotal role in understanding the evolution of topography in northwestern South America and the development of large river systems, such as the Amazon, Orinoco, and Magdalena rivers. However, understanding of the basement framework has been hindered by challenging access, security concerns, tropical climate, and outcrop scarcity. Further, an insufficient geochronologic characterization of Andean basement complicates provenance interpretations of adjacent basins and restricts understanding of the paleogeographic evolution of southern Colombia. To address these issues, this paper presents a zircon U-Pb geochronological dataset derived for 24 bedrock samples and 19 modern river samples. The zircon U-Pb results reveal that the Eastern Cordillera of southern Colombia is underlain by basement rocks that originated in various tectonic events since ca. 1.5 Ga, including the accretion of discrete terranes. The oldest rocks, found in the Garzon Massif, are high-grade metamorphic rocks with contrasting Proterozoic protolith crystallization ages. Whereas the SW part of the massif formed during the Putumayo Orogeny (ca. 1.2-0.9 Ga), we report orthogneisses for the NE segment with protoliths formed at ca. 1.5 Ga, representing the NW continuation of the Rio Negro Jurena province of the Amazonian Craton. In contrast, crystalline rocks of the Central Cordillera primarily consist of Permian-Triassic (ca. 270-250 Ma) and Jurassic-Cretaceous (ca. 180-130 Ma) igneous rocks formed in a magmatic arc. In southernmost Colombia, the Putumayo Mountains mainly consist of Jurassic-Cretaceous (180-130 Ma) plutonic and volcanic rocks. Furthermore, we analyzed the heavy mineral abundances in modern river sands in southern Colombia (spanning 1°N-5°N) and found that key minerals such as garnet and epidote can be utilized to trace highgrade metamorphic and igneous lithologies, respectively, in the river catchments. The differentiation of basement ages for separate tectonic provinces, combined with heavy mineral abundances in modern sands, can serve as unique fingerprints in provenance analyses to trace the topographic and exhumational evolution of different Andean regions through time. [ABSTRACT FROM AUTHOR]

A new monotypic genus of the subfamily Theraphosinae Thorell, 1869 is described from the Western Cordillera of the Andes in northern Ecuador. The new genus is diagnosed by its distinctive male palpal morphology, including a semi-spatulate bulb caused by a well developed retrolateral inferior keel, presence of a cymbial apophysis, absence of a tibial apophysis, and a new character described in this contribution as a retrolateral tegular process. We comment on the similarities in male palpal bulb morphology with other neotropical genera and provide a preliminary phylogenic placement based on morphology. [ABSTRACT FROM AUTHOR]

The genus Dendrophorbium occurs in South America with one species known from the Caribbean. Despite recent advances in taxonomy and phylogeny, there is a still lack of molecular studies on the delimitation and identification of the genus. Dendrophorbium is known to occupy a wide range of ecosystems mostly restricted to subtropical montane forests and montane scrub vegetation of the central Andes. In this study, a review of the species occurring in Peru is presented, in addition to material examined at different herbaria. The new combination D. ligulatum which is separated from D. yalusay, and the new species, D. arachnoideum is described from the department of Huánuco in central Peru. The species are assessed using the standards of the IUCN and additional notes are given. [ABSTRACT FROM AUTHOR]

Tota is an Andean lake located in the Altiplano of the Eastern Andes of Colombia where socio-politically hierarchical societies of the Herrera and Muisca, flourished for millennia. To them, the lake and surrounding forest were places used for diverse of activities including religious rituals. In this study we produced a multi-proxy paleolimnological reconstruction using diatoms, isotopes, and geochemistry, to try to understand the lake's pathways of change in response to natural climatic variations and anthropogenic activities. The diatom record is dominated by tychoplanktonic Staurosirella dubia and planktonic Aulacoseira species including species A. cf lirata, A. granulata, A. distans, and A. ambigua. Diatoms were grouped into functional groups and used to infer limnological changes that were further complemented with the geochemistry of the sediments to reconstruct the past environment. Results show three main periods in which the lake changed significantly, these are dated from ~800 to 1200, 1200 to 1500, and 1500 to 1900 CE. A correlation with the archeological record of the region, ethnohistoric accounts and climate suggests that these changes occurred simultaneously with changes in archeological stages, the Spanish arrival, and more recently by the industrial revolution, and the Little Ice Age. [ABSTRACT FROM AUTHOR]

Thomasomys is the most diverse genus of the Sigmodontinae subfamily, comprising at least 51 species. Despite recent systematic advances, the monophyly of this genus, the proposed species groups and their content, and the species limits are not yet firmly established. Using a well‐sampled mitochondrial dataset, we aim to test the monophyly of the genus, infer phylogenetic relationships among species and species groups and test the limits between valid species and candidate species. For this, we used a large matrix of 272 partial non‐redundant sequences of the cytochrome b mitochondrial gene from 40 valid and 20 candidate species. Using probabilistic approaches on this dataset, we inferred Thomasomys phylogenetic relationships and explored species boundaries using four unilocus species delimitation methods (ABGD, ASAP, bPTP and GMYC). Thomasomys sensu stricto was recovered monophyletic and well‐supported, excluding a Peruvian lineage misidentified as part of the genus. Analyses consistently recovered 10 well‐supported major clades and several paraphyletic or polyphyletic species. Delimitation methods and genetic divergences estimated that Thomasomys comprises between 81 and 93 putative species, thus potentially doubling the species diversity of Thomasomys. Such a result clearly calls for an urgent taxonomic revision of this genus and the use of further molecular loci within an integrative taxonomic approach to describe its diversity and understand its evolutionary history. [ABSTRACT FROM AUTHOR]

This paper explores the response to Holocene ash inundation in different sub‐environments of two fluvio‐lacustrine systems, Las Piedritas and Totoral, focussing on the processes of volcaniclastic remobilisation. Sediment cores and outcrops were used to recognise three deposit types, noting how some differ from lahars, through sedimentological and stratigraphic analysis: (1) thick, laterally discontinuous, pumice‐dominated deposits occur overlying alluvial plain and lower terrace surfaces across both watersheds; (2) chaotic, extremely poorly sorted and matrix‐supported beds composed of both epiclastic and pyroclastic material occur as two conspicuous deposits at Las Piedritas outcrops, in a low‐gradient confined channel setting; and (3) layers with an exclusively pyroclastic composition and no flow sedimentary structures or fragment roundness were found draping each of the two chaotic intervals and intercalating with the background sediment in Las Piedritas prodelta. Thick pumice packages capping the floodplains resulted from the overflow of streams carrying a floating pumice load. Due to its positive buoyancy, the pumice is transported as a slowly moving overlying mantle without mixing with the streamflow. The disorganised pattern and poor sorting of the matrix‐rich polymictic beds are consistent with laminar, gravity‐driven, high‐concentration flows. They constitute secondary lahars, originating upstream from large run‐off processes that reworked a pyroclastic substrate. The lack of reworking features in the vitric‐rich units identified in the lake core retrieved from Las Piedritas prodelta, as well as the continuous and widespread occurrences of those interbedded in upstream outcrops, indicate an airfall origin. No reworked tephra unit is recognised in the prodelta sediment record, although various deposits from the hydrologic remobilisation of airfall tephra are found along the subaerial portion of both watersheds. Apparently, large amounts of flotation‐remobilised tephra were retained on the delta plain, while another considerable fraction would have been carried away from the creek mouth under the influence of dominant regional winds. [ABSTRACT FROM AUTHOR]

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Since the times of the Incas, farmers in the remote Andes of Peru have constructed terraces to grow crops in a landscape characterized by steep slopes, semiarid climate, and landslide geohazards. Recent investigations have concluded that terracing and irrigation techniques could enhance landslide risk due to the increase in water percolation and interception of surface flow in unstable slopes, leading to failure. In this study, we generated an inventory of 170 landslides and terraced areas to assess the spatial coherence, causative relations, and geomechanical processes linking landslide presence and Inca terraces in a 250 km2 area located in the Ticsani valley, southern Peru. To assess spatial coherence, a tool was developed based on the confusion matrix approach. Performance parameters were quantified for areas close to the main rivers and communities yielding precision and recall values between 64% and 81%. On a larger scale, poor performance was obtained pointing to the existence of additional processes linked to landslide presence. To investigate the role of other natural variables in landslide prediction, a logistic regression analysis was performed. The results showed that terrace presence is a statistically relevant factor that bolsters landslide presence predictions, apart from first-order natural variables like distance to rivers, curvature, and geology. To explore potential geomechanical processes linking terraces and slope failures, FEM numerical modeling was conducted. Results suggested that both decreased permeability and increased surface irrigation, at 70% of the average annual rainfall, are capable of inducing slope failure. Overall, irrigated terraces appear to further promote slope instability due to infiltration of irrigation water in an area characterized by fluvial erosion, high relief, and poor geologic materials, exposing local communities to increased landslide risk. [ABSTRACT FROM AUTHOR]

Knowing the centers of richness and endemism is crucial for prioritizing biodiversity conservation efforts, particularly in taxa susceptible to environmental changes and in regions of significant biological importance. We used species occurrence data from species lists, online information sources, and herbarium records to identify the centers of endemism of liverworts in Colombia. Sampling biases were assessed using the 'sampbias' package. Geospatial analyses were applied to identify species richness and endemism centers, with the latter identified using the NDM/VNDM algorithm. Species conservation status was evaluated based on IUCN Red List criterion B using the 'ConR' package. Despite low sampling efforts across all regions, the collection bias model revealed disparities in sampling, with fewer expected records in the Orinoco, Caribbean, and Amazon regions, highlighting the need for new inventories in these priority areas. The Andean (567 total species, 16 endemic species and subspecies) and Pacific (301 total species, 7 endemic species) regions stood out with higher richness. Two centers of endemism were identified: the Pacific and the Andean regions, emerging as priorities for conservation investments. Only 4% of the total area of the centers of endemism in Colombia was found within protected areas (PAs), and 40% of species were classified as threatened. Despite the challenges, 22.7% of the endemic species are found within PAs, underscoring the urgent need for efficient PA management, especially those located along the central Andes Mountain range. [ABSTRACT FROM AUTHOR]

The skill, assumptions, and uncertainty of machine learning techniques (MLTs) for downscaling global climate model's precipitation to the local level in Bolivia were assessed. For that, an ensemble of 20 global climate models (GCMs) from CMIP6, with random forest (RF) and support vector machine (SVM) techniques, was used on four zones (highlands, Andean slopes, Amazon lowlands, and Chaco lowlands). The downscaled series' skill was evaluated in terms of relative errors. The uncertainty was analyzed through variance decomposition. In most cases, MLTs' skill was adequate, with relative errors less than 50%. Moreover, RF tended to outperform SVM. Robust (weak) stationary (perfect prognosis) assumptions were found in the highlands and Andean slopes. The weakness was attributed to topographical complexity. The downscaling methods were shown to be the dominant source of uncertainties. This analysis allowed the derivation of robust future projections, showing higher annual rainfall, shorter dry spell duration, and more frequent but less intense high rainfall events in the highlands. Apart from the dry spell's duration, a similar pattern was found for the Andean slopes. A decrease in annual rainfall was projected in the Amazon lowlands and an increase in the Chaco lowlands. [ABSTRACT FROM AUTHOR]

The Andean uplift and the concomitant aridification drove the rapid diversification of several plant lineages that were able to colonize warmer and drier habitats at low elevations and wetter and colder habitats at high elevations. These transitions may be facilitated by shifts in plant strategies to cope with drought and cold, which in turn can trigger episodes of accelerated species diversification. Here, we used four nuclear DNA markers to infer phylogenetic relationships of 80 Adesmia species of annuals, perennial herbs, shrubs and small shrubs that occur in Chile and Argentina. We reconstructed ancestral states for area, climatic niche and growth form to explore how Andean uplift and aridification promoted Adesmia diversification. We also performed logistic and linear regression analyses between different components of growth form (life span, woodiness and plant height) and climate. Finally, we estimated speciation rates across the phylogeny. Our results suggest that the ancestor of Chilean Adesmia was a perennial herb that probably originated in the high Andes of northern and central Chile. The low elevations of Central Chile were colonized in the late Miocene, whereas the high latitudes of Patagonia and the hyperarid coastal Atacama Desert were colonized repeatedly since Pliocene by lineages with different growth forms. Multiple and bidirectional transitions between annual and perennial habits and between herbaceous and woody habits were detected. These shifts were not correlated with climate, suggesting that the different growth forms are alternative and successful strategies to survive unfavorable seasons of both desert and high Andes. Net diversification analysis indicated a constant rate of diversification, suggesting that the high species diversity of Adesmia that occur in Chile is due to a uniform speciation process rather than to accelerated episodes of speciation. [ABSTRACT FROM AUTHOR]

The Andes region has an exceptional record of high-altitude settlements integrated within widespread regional chains of mobility and exchange. The Sierra de Aconquija (NW Argentina, south-central Andes) is an effective climatic barrier that has afforded an enduring indigenous approach to land use, mobility, and exchange over millennia. Despite this rich history, the Sierra has been largely considered marginal in pre-Columbian regional cultural developments. Today, the expansion of extractive industries threatens the region's heritage and the sustainable futures of local communities. Innovative, integrative methodologies are needed for landscape characterisation, heritage assessment, and sustainable policy development. Building on earlier work, we undertook the first comprehensive mapping of archaeological features over 3800 sq. km of the Sierra using interpreter-led assessment of commercial and open-access satellite imagery and DSM data, to verify earlier assumptions and to identify previously unnoticed trends in the aggregation, distribution, and connectivity of archaeological features. The mapping identified 6794 features distributed unevenly but with clear tendencies towards maximising topographic, ecologic, and connectivity advantages expressed consistently across the study area. The outcomes confirm the important role the Sierra had in pre-Hispanic times, highlighting the significance of ancient indigenous practices for the sustainability of vulnerable upland landscapes both in the Andes and worldwide. [ABSTRACT FROM AUTHOR]

Lower Miocene plutons exposed in the Western Cordillera of Colombia record the reinitiation of continental arc magmatism in the Northern Andes after a period of magmatic quiescence between the Late Eocene and Early Miocene. Petrography, U-Pb zircon geochronology, whole-rock geochemistry, mineral chemistry, and zircon Hf isotope data from these plutons are used to reconstruct the Miocene magmatic evolution in the Colombian Andes and understand its relation with the major plate-tectonic reorganization experienced by the NW South American continental margin during the Lower Miocene. We examined a suite of gabbros, granodiorites and tonalites from Danubio, Pance and Tatamá plutons, formed between 21 Ma and 15 Ma. Gabbros present highly positive εHf values (+13.5 and + 11.5) with low Th/La and La/Yb ratios, and granodiorites and tonalites present lower εHf values (+14.3 to + 6.4). The results of this contribution show a major asthenospheric source with absent or minor melting of subducted sediments, and contribution of oxidized aqueous fluids. The compositional diversification of these magmas was controlled by fractional crystallization and, in the Tatamá pluton, also by local assimilation of continental crust at lower crustal levels of the upper plate. Subsequently, these magmas were emplaced in the Cretaceous to Palaeogene volcanic and sedimentary rocks in the uppermost crust. The renewed magmatic activity recorded by the studied plutons suggests a normal to step subduction of the elder Farallon Plate during the Neogene subduction re-organization in the Colombian Andes, as well as the local presence of continental crust fragments in the lower crust of the Western Cordillera of Colombia. [ABSTRACT FROM AUTHOR]

We studied Tachymenis peruviana 's thermoregulatory strategy, and microhabitat use and selection in an open enclosure at 3400 m elevation during the wet season. We expected that thermal conditions at a high elevation locality would result in differences in the thermoregulatory efficiency within microhabitats through their use and selection along the day. We obtained preferred temperatures and critical thermal tolerance limits of field-captured individuals. Some individuals were kept in an open enclosure with access to four microhabitat types with retreats where to hide. We measured individuals' field-body temperatures along with substrate and air temperatures, and recorded where the snakes were found according to microhabitat type and if they were inside or outside retreats. Meanwhile, operative temperatures were registered every hour at each offered microhabitat between 08:00 to 18:00 hours. The body and microenvironmental temperatures were highly correlated. Even though the enclosure offered appropriate thermal sources for snakes to reach their preferred temperatures, results indicate that the species met its energy requirements with a low effort in this high elevation enclosure. Almost three-quarters of the observations were recorded in retreat sites, showing a lower thermoregulatory efficiency compared to when they were captured aboveground. A comparative evaluation of the thermoregulation of the species in the field within a variety of thermal regimes experienced along its altitudinal and latitudinal range must still be carried out to better understand the species' thermoregulatory strategies across the Andes. [ABSTRACT FROM AUTHOR]

Litter decomposition is not fully explained by the general triangle of climate, litter quality and soil decomposers. Therefore, other theoretical frameworks, such as Home-Field Advantage (HFA), have emerged to explain the remaining variation of decomposition. HFA states that litter decomposes faster in their site of origin (home) than far from it (away). However, there are no consistent patterns of HFA and this can varies depending the ecosystem and plant species analyzed. One of the most variable ecosystems in terms of species biodiversity turnover, topography, and soil conditions are the Upper Andean Tropical Forests (UATF), but to date there is no study testing HFA in this ecosystem. Here, HFA was tested through a reciprocal litterbag translocation field experiment across different UATF. The experiment comprised 2520 litterbags placed in 14 20 x 20 m plots that belonged to four sites to analyze decomposition of 15 plant species for 18 months. Of these 15 species, seven were present at only one site. The mean decomposition was calculated for all 15 species to determine the relative decomposition at each site and the decomposition of the seven species at home and away sites was analyzed through two-way ANOVA (sites x species) and linear mixed models. I contrasted environmental charcteristics between sites including litter depth, slope, leaf area index, canopy openness, and microclimatic variables. The results showed that the pattern of decomposition was always the same, no matter the origin of the species and the decomposition period. Microclimate, litter depth, and slope varied between sites, yet these differences were not enough to influence affinity effects of decomposition, as relative decay rates were similar between home and away sites. Overall, no HFA was found in UATF possibly because: (i) strong environmental filters along montane forests homogenize decomposer communities; (ii) high diversity in litters drive decomposers with high ability to degrade different organic compounds; (iii) little adaptation of decomposers to recurrent litter as they respond mainly to changes in litter quality. These results imply that changes in species composition by current anthropogenic pressures could have profound impacts on carbon cycle and nutrient fluxes depending on the identity of species arriving in UATF. [ABSTRACT FROM AUTHOR]

Automated radio telemetry systems (ARTS) have the potential to revolutionise our understanding of animal movement by providing a near‐continuous record of individual locations in the wild. However, localisation errors in ARTS data can be very high, especially in natural landscapes with complex vegetation structure and topography. This curtails the research questions that may be addressed with this technology. We set up an ARTS grid in a valley with heterogeneous vegetation cover in the Colombian high Andes and applied an analytical pipeline to test the effectiveness of localisation methods. We performed calibration trials to simulate animal movement in high‐ or low‐flight, or walking on the ground, and compared workflows with varying decisions related to signal cleaning, selection, smoothing, and interpretation, along with four multilateration approaches. We also quantified the influence of spatial features on the system's accuracy. Results showed large variation in localisation error, ranging between 0.4–43.4 m and 474–1929 m, depending on the localisation method used. We found that the selection of higher radio signal strengths and data smoothing based on the temporal autocorrelation are useful tools to improve accuracy. Moreover, terrain ruggedness, height of movement, vegetation type, and the location of animals inside or outside the grid area influence localisation error. In the case of our study system, thousands of location points were successfully estimated for two high‐altitude hummingbird species that previously lacked movement data. Our case study on hummingbirds suggests ARTS grids can be used to estimate small animals' home ranges, associations with vegetation types, and seasonality in occurrence. We present a comparative localisation pipeline, highlighting the variety of possible decisions while processing radio signal data. Overall, this study provides guidance to improve the resolution of location estimates, broadening the application of this tracking technology in the study of the spatial ecology of wild populations. [ABSTRACT FROM AUTHOR]

We revise the taxonomy of the frog genus Noblella on the basis of a molecular phylogeny. Previous studies recognized that Noblella is non-monophyletic, with one clade distributed from southeastern Peru to northeastern Bolivia and adjacent areas in Brazil and another clade distributed from northern Peru to Ecuador and southeastern Colombia. The lack of sequences from the type species Noblella peruviana prevented the investigation of its phylogenetic position and the status of related taxa. Our rediscovery after more than 115 years allowed for the inclusion of DNA sequences of Noblella peruviana obtained from specimens collected at the type locality in southeastern Peru. We inferred a phylogeny based on a concatenated dataset (three mitochondrial and two nuclear loci) using Bayesian and maximum likelihood methods. Our phylogeny corroborated the non-monophyly of Noblella and helped resolve the status of related taxa, including Psychrophrynella bagrecito, the type species of the genus Psychrophrynella (rediscovered after 42 years). We identified a clade containing N. peruviana, P. bagrecito, and other species of Noblella and Psychrophrynella distributed in southern Peru. Given that the name Noblella predates Psychrophrynella, we propose that Psychrophrynella should be considered a junior synonym of Noblella. The second clade contains species of Noblella distributed in Ecuador and northern Peru, including N. myrmecoides, which used to be the type species of the genus Phyllonastes. Consequently, we propose to reinstate the genus Phyllonastes to accommodate all species of Noblella distributed in Ecuador, northern Peru, southeastern Colombia, and adjacent areas in Brazil. We present an updated taxonomy including new combinations for 12 species and reinstatements for three species. [ABSTRACT FROM AUTHOR]

Premise: Agriculture expansion, livestock, and global change have transformed biological communities and altered, through aerosols and direct deposition, N:P balance in soils of inter‐Andean valleys, potentially affecting flowering phenology of many species and thereby flowering synchrony and plant reproduction. Methods: We evaluated the influence of variation in temperature and moisture along the local elevational gradient and treatments with the addition of N and P and grazing on flowering synchrony and reproduction of Croton, a dominant shrub of the inter‐Andean dry scrub. Along the elevational gradient (300 m difference between the lowest and highest site), we set up plots with and without grazing nested with four nutrient treatments: control and addition of N or P alone or combined N + P. We recorded the number of female and male flowers in bloom monthly from September 2017 to August 2019 to calculate flowering synchrony. We assessed fruiting, seed mass, and pre‐dispersal seed predation. Results: Higher growing‐season soil temperatures, which were negatively associated with local elevation and higher nitrogen availability promoted flowering synchrony of Croton, particularly among larger plants. Greater flowering synchrony, high soil temperatures, and addition of N + P resulted in production of more fruits of Croton, but also intensified pre‐dispersal seed predation. Conclusions: Temperature, availability of moisture throughout the elevational gradient, and nutrient manipulation affected flowering synchrony, which subsequently affected production of fruits in Croton. These results emphasize the critical role of current anthropogenic changes in climate and nutrient availability on flowering synchrony and reproduction of Croton, a dominant plant of the inter‐Andean scrub. [ABSTRACT FROM AUTHOR]

Evolution proceeds unevenly across the tree of life, with some lineages accumulating diversity more rapidly than others. Explaining this disparity is challenging as similar evolutionary triggers often do not result in analogous shifts across the tree, and similar shifts may reflect different evolutionary triggers. We used a combination of approaches to directly consider such context-dependency and untangle the complex network of processes that shape macroevolutionary dynamics, focusing on Pleurodonta, a diverse radiation of lizards. Our approach shows that some lineage-wide signatures are lost when conditioned on sublineages: while viviparity appears to accelerate diversification, its effect size is overestimated by its association with the Andean mountains. Conversely, some signals that erode at broader phylogenetic scales emerge at shallower ones. Mountains, in general, do not affect speciation rates; rather, the occurrence in the Andean mountains specifically promotes diversification. Likewise, the evolution of larger sizes catalyzes diversification rates, but only within certain ecological and geographical settings. We caution that conventional methods of fitting models to entire trees may mistakenly assign diversification heterogeneity to specific factors despite evidence against their plausibility. Our study takes a significant stride toward disentangling confounding factors and identifying plausible sources of ecological opportunities in the diversification of large evolutionary radiations. [ABSTRACT FROM AUTHOR]

Chytridiomycosis is a fungal disease responsible for massive amphibian die-offs worldwide, caused by the fungus Batrachochytrium dendrobatidis (Bd). Potential symbiotic relationships between frogs and the bacteria residing on their skin—referred to as skin-bacteria—may inhibit Bd growth, aiding in resistance to this lethal disease. This research had three main objectives: (1) to detect the presence of Bd in native populations of Atelopus balios, A. bomolochos, and A. nanay in the central Andes and coastal southern regions of Ecuador; (2) to identify the culturable skin-bacteria; and (3) to analyze differences among the bacterial communities in the three Atelopus species studied. Skin swabs were collected from two populations of A. balios (107–203 m a.s.l.) and one population each of A. bomolochos and A. nanay (3,064–3,800 m a.s.l.). These swabs served two purposes: first, to detect Bd using conventional PCR; and second, to isolate culturable bacteria, which were characterized through DNA sequencing, molecular phylogeny, and community composition similarity analysis (Jaccard index). Results showed that Bd was present in all species, with positive Bd PCR amplification found in 11 of the 12 sampled amphibians. The culturable skin-bacteria were classified into 10 genera: Pseudomonas (31.4%), Stenotrophomonas (14.3%), Acinetobacter (11.4%), Serratia (11.4%), Aeromonas (5.7%), Brucella (5.7%), Klebsiella (5.7%), Microbacterium (5.7%), Rhodococcus (5.7%), and Lelliottia (2.9%). The Jaccard index revealed that bacterial genera were least similar in A. bomolochos and A. balios (J = 0.10), while the highest similarity at the genus level was between A. bomolochos and A. nanay (J = 0.33). At the clade-species level, only A. bomolochos and A. nanay show common bacteria (J = 0.13). Culturable bacterial communities of specimens diagnosed as Bd positive (n = 10) or Bd negative (n = 1) share a J value of 0.1 at genus and 0.04 at species-clade level. The prevalence of Bd and the composition of cutaneous bacteria could be influenced by Bd reservoirs, Atelopus biology, and intrinsic environmental conditions. This research contributes to understanding the relationship between endangered Andean species and Bd, and explores the potential use of native skin-bacteria as biocontrol agents against Bd. [ABSTRACT FROM AUTHOR]

High mountain rainforests are vital in the global energy and carbon cycle. Understanding the exchange of energy and carbon plays an important role in reflecting responses to climate change. In this study, an eddy covariance (EC) measurement system installed in the high Andean Mountains of southern Ecuador was used. As EC measurements are affected by heterogeneous topography and the vegetation height, the main objective was to estimate the effect of the sloped terrain and the forest on the turbulent energy and carbon fluxes considering the energy balance closure (EBC) and the heat storage. The results showed that the performance of the EBC was generally good and estimated it to be 79.5%. This could be improved when the heat storage effect was considered. Based on the variability of the residuals in the diel, modifications in the imbalances were highlighted. Particularly, during daytime, the residuals were largest (56.9 W/m2 on average), with a clear overestimation. At nighttime, mean imbalances were rather weak (6.5 W/m2) and mostly positive while strongest underestimations developed in the transition period to morning hours (down to −100 W/m2). With respect to the Monin–Obukhov stability parameter ((z − d)/L) and the friction velocity (u*), it was revealed that the largest overestimations evolved in weak unstable and very stable conditions associated with large u* values. In contrast, underestimation was related to very unstable conditions. The estimated carbon fluxes were independently modelled with a non-linear regression using a light-response relationship and reached a good performance value (R2 = 0.51). All fluxes were additionally examined in the annual course to estimate whether both the energy and carbon fluxes resembled the microclimatological conditions of the study site. This unique study demonstrated that EC measurements provide valuable insights into land-surface–atmosphere interactions and contribute to our understanding of energy and carbon exchanges. Moreover, the flux data provide an important basis to validate coupled atmosphere ecosystem models. [ABSTRACT FROM AUTHOR]

We report a patient with lobomycosis caused by Paracoccidioides loboi fungi in the Andes-Amazon region of Bolivia. We examined clinical, epidemiologic, and phylogenetic data and describe potential transmission/environmental aspects of infection. Continued surveillance and identification of lobomycosis cases in South America are crucial to prevent the spread of this disease.

This article addresses the poetic inflection of the last decade in Peruvian poetry; At the same time, it proposes that, in this period, there has been a notable shift in writing by women as an expression of a period characterized by “empolleramiento”. We maintain that this turn is characterized by irreverence, by the hybrid management of forms and by a unique way of tuning into reality. Our study focuses on three creators: Gloria Alvitres, Karuraqmi Puririnay and Lourdes Aparición. To analyze their texts, we appeal to a concept associated with Andean clothing, namely: the skirt. Thus, brooding will be used as an inclusive notion in which the situation of women who are not in the center, who are not part of the canon and who were despised by political power is described and the characteristics of these emerging poetics are examined

Thirty-six species and three genera of moths are recorded for the first time in Colombia, in the families Notodontidae (31 spp., 2 genera), Saturniidae (4 spp., 1 genus), and Sphingidae (1 sp.). All records are based on photographs of live individuals attracted to white and UV lights.

Abstract Seasonal snow in the extratropical Andes is a primary water source for major rivers supplying water for drinking, agriculture, and hydroelectric power in Central Chile. Here, we used estimates from the Moderate Resolution Imaging Spectroradiometer (MODIS) to analyze changes in snow cover extent over the period 2001–2022 in a total of 18 watersheds spanning approximately 1,100 km across the Chilean Andes (27–36°S). We found that the annual snow cover extent is receding in the watersheds analyzed at an average pace of approximately 19% per decade. These alarming trends have impacted meltwater runoff, resulting in historically low river streamflows during the dry season. We examined streamflow records dating back to the early 1980s for 10 major rivers within our study area. Further comparisons with large-scale climate modes suggest that the detected decreasing trends in snow cover extent are likely driven by the poleward migration of the westerly winds associated with a positive trend in the Southern Annular Mode (SAM).

El presente estudio pretende dar información sobre el fenómeno de la alopatría aplicado a la especiación que acontece en algunos rhopaloceros colombianos que vuelan en formaciones vegetales similares pero separadas por cadenas montañosas pertenecientes a los Andes. Se incluyen algunos antecedentes previos y varias de las teorías surgidas a este respecto explicadas con la biogeografía y génesis de las mariposas neotropicales.

Following the IUCN criteria, we assess the risk of extinction for five orchid species recorded for the first time from Colombia: Acianthera viridis (Luer & Hirtz) Luer, Dichaea lankesteri Ames, Epidendrum lavendulum Hágsater, Masdevallia ariasii Luer, and Stenia stenioides (Garay) Dodson & R.Escobar. We propose a preliminary global Red List categories of Endangered, Least Concern, Endangered, Vulnerable, and Least Concern, respectively, for these species. The main threats of these orchids are habitat degradation, small and degraded AOO and EOO, and a small number of known populations. The Caraño river basin, where these species occur in Colombia, is an important site for orchid conservation. Consequently, strategies are needed to ensure its preservation.

Climate conditions have a strong influence on the distribution of many natural communities; thus, the influence of global climate change may alter ecosystems. High-altitude wetlands in the Central Andes of Argentina (CAA) provide relevant ecosystem benefits and promote human activities. However, a degradation of Andean wetlands has been observed and documented in the last decades. Projecting the impacts of climate change on future distribution of wetlands is an essential subject in ecological studies. In this work, the present and future suitability for wetland systems in a pristine section of the CAA using spatial distribution modeling under low and high-emission scenarios are explored. The studied wetlands are strongly driven by bioclimatic variables such as mean annual temperature, precipitation, and its seasonality. Projections show that most of the currently occupied areas will modify under future climate conditions. Changes in temperature and precipitation patterns will decrease the potential suitability in low elevation areas for the next decades for the species inhabiting there, especially south of 29 °S. Additionally, future warmer climatic conditions, greater temperature variability, and reduction in precipitation would probably affect the snow cover and the available water supply which are key limiting factors for the distribution of Andean wetlands. This research is a contribution to understanding possible effects of climate change on high-altitude ecosystems. Mitigation measures for conservation of wetlands in CAA are immediately required to compensate for the impact of climate change under future environmental conditions.

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.

Societal Impact Statement Palms provide vital plant resources and ecosystem services to people across the tropics. To improve conservation guidance, a “health check” of palms in two highly threatened biodiversity hotspots in Colombia and Ecuador was undertaken. Palms are very diverse in these regions, but over one third are threatened with extinction now, especially among endemic species. Widespread and useful palms are also under intense human pressure and need to be prioritized in terms of sustainable management practices. Given the importance of palms for humans, inclusive conservation actions should be continued in both countries in order to safeguard this resource. Summary Palms provide central plant resources to societies in the tropics, especially in the Global South. The western Pacific and Andean regions of Colombia and Ecuador host two hotspots of biodiversity. To prioritize conservation policies towards palms, we undertook a conservation assessment of species in the region. We compiled a taxonomically verified database of specimens collected in both hotspots. We inferred preliminary conservation assessments using International Union for Conservation of Nature (IUCN) Criteria B. In addition, we evaluated the level of exposure of palms to human use and population density using the anthrome concept. We documented 144 native palm species in 33 genera occurring in both hotspots of Colombia and Ecuador. Of these, 55 are endemic to this region. We recorded 133 species for Colombia, 43 endemic, and 71 species for Ecuador, 9 endemic. A third of all palm species in the region are potentially threatened with extinction (50/144) and 12 as preliminary Critically Endangered. Aiphanes and Geonoma have the highest number of threatened species. In total, 60% of palm specimens were collected in the “low human impact” anthrome type. In contrast, 41% of specimens occur in high human density areas. The two hotspots of biodiversity in Colombia and Ecuador are very diverse in palms. However, we show that this diversity is under threat and is predominantly found in areas impacted by human activities. Extinction risk is highest in endemic species in both countries. Widespread and useful palm species also face threats linked to overexploitation or habitat loss. Inclusive conservation measures should be designed to conserve, together with communities, this plant resource.

We present a discriminant metric study of stone projectile points (n = 422) from 21 archaeological sites in the Andes of South America (16–37°S). We use comparative datasets critically, since darts may have been smaller than previously thought. We assess the use-life of each point and tie them to reliable chronological sequences, in order to increase the reliability of our data. Our results show that in the Lake Titicaca Basin and northwestern Argentina, bows had replaced spearthrowers by 1780–950 cal BP, prior to the development of complex societies such as Wari and Tiwanaku. South of 29°S, the results suggest that bow technology was transmitted from north to south, since the earliest arrow-sized points at 29°S date to 3000 cal BP and at 37°S, 1800–1000 cal BP. North of 34°S, the continental limit of domesticated plants and animals, there is a gradual abandonment of the spearthrower. South of 34°S in northern Patagonia, both weapon systems coexisted. We suggest that bow and arrow technology was not an independent invention in the southern Andes, but instead, it appeared in new groups via macroregional technological borrowing among Andean herders. [ABSTRACT FROM AUTHOR]

The extent to which archery technology affected social organization in the Andes region of South America remains understudied. To identify the timing and consequences of archery technology in the Lake Titicaca Basin, this analysis examines metric data from 1179 projectile points from the region, 11–1.0 cal. ka. We find that the greatest decrease in projectile point size occurred across the Late/Terminal Archaic and Formative/Tiwanaku period boundaries, 5.0 and 1.5 cal. ka, respectively. We do not find a statistically significant decrease in size during any other transition, including the Terminal Archaic/Formative boundary, which was previously hypothesized to have been the time when archery technology first appeared in the region. These results instead favor the hypothesis that archery technology first entered the region during the Terminal Archaic Period, 5.0–3.5 cal ka. We furthermore observe that this technological transition coincided with the growth of settlements, a surge in the use of exotic goods such as obsidian, a low level of inter-group violence, and incipient agropastoralism—a pattern that intensified during the subsequent Formative period when monumental ceremonial centers emerged. These findings lead us to propose a model for South American archery technology in which its appearance after 5000 years ago contributed to the emergence of new cooperative dynamics that expanded regional exchange networks and community aggregation. [ABSTRACT FROM AUTHOR]

We describe a new species of Centrolene from the Subandean Cordillera of Kutukú in southeastern Ecuador. The new species differs from all other glassfrogs by the combination of the following characters: presence of processes of vomers but without vomerine teeth; humeral spines in males; dorsum green with light green dots and without dark marks; dorsal skin with abundant tubercles; all visceral peritonea translucent (except for pericardium); and small body size (snout-vent length 21.5–21.9 mm in adult males). The new species is sister to Centrolene camposi from the Western Cordillera of the Andes of southwestern Ecuador, and together they form a clade with C. condor from the Subandean Cóndor Cordillera in southeastern Ecuador. Our time tree suggests that the new species originated at the end of the Pliocene. In addition, we present new information for C. zarza, expanding its geographic range across the southeastern Andes and the Kutukú and Cóndor cordilleras, amending its definition and diagnosis, and offering new information on its natural history and extinction risk. We also discuss the taxonomic status of Ecuadorian populations reported as C. huilensis and conclude that they are C. muelleri based on their close phylogenetic relationships and morphological similarity to samples of C. muelleri from Peru. Centrolene huilensis is a valid species and not closely related to C. muelleri. [ABSTRACT FROM AUTHOR]

This study contributes to our knowledge of the flora from high Andes of Bolivia by the description and characterization of five new, high-altitude species of Gentianaceae: Gentianella campaniflora, G. potosiana, G. pringlei, G. puberula, and G. samae. The new species are compared with similar species in their morphology, ecology, phenology and distribution. Line drawings and photographs serve to illustrate the species. [ABSTRACT FROM AUTHOR]