Alfredo F. Fuentes

Summary: Hybridization and introgression are increasingly recognized as important in plant evolution, yet their prevalence and consequences remain poorly understood in tropical Andean trees, where species coexist at low densities and turn over rapidly across elevation gradients. Here, we investigate whether species boundaries are maintained among 10 congeneric Andean Prunus L. species distributed across the Andes‐Amazon elevational gradient by reconstructing phylogenetic relationships, divergence times, and patterns of historical and recent gene flow. We find that Andean Prunus diversified during the Miocene, likely in response to novel habitat opportunities resulting from mountain uplift, combined with allopatric processes. Despite this evolutionary divergence, these species show extensive ancient introgression and recent admixture, indicating that species boundaries remain permeable across both ecological and phylogenetic distance. Together, these results suggest that Andean Prunus comprise distinct but evolutionarily connected lineages that retain morphological identity while potentially functioning as a long‐lived syngameon, with implications for understanding the origin and maintenance of tropical tree diversity and future response to global change.

Plant functional composition and diversity are key dimensions of biodiversity that determine ecosystem functioning. While spaceborne remote sensing has enabled predicting functional composition, the prediction accuracy is still limited, particularly in tropical forests where persistent cloud cover, signal saturation and limited field data constrain conventional approaches, and large-scale spatial patterns of functional diversity remain understudied. Recent advances in self-supervised learning have produced representative embeddings from unlabeled satellite data, offering the potential to overcome such challenges. Here, we model and map community-weighted mean (CWM) and standard deviation (CWSD) of plant traits, representing functional composition and diversity, respectively, across the Amazon at 1 km resolution using >1,300 field plots of tree species composition and nine leaf, stem, structural and reproductive traits. We evaluate AlphaEarth, TESSERA, and SatCLIP embeddings, representing spatiotemporal features of multimodal information, temporal dynamics and geolocation characteristics, respectively, against conventional Sentinel-1/2 predictors. We show that self-supervised embeddings consistently outperform conventional satellite predictors. AlphaEarth combined with environmental variables provided the best balance in accuracy, resolution, and dimensionality, achieving mean R2 of 0.3-0.6 for CWM traits and 0.1-0.5 for CWSD traits. Variable importance analyses identified the combined influence of climate variability, soil fertility and satellite embeddings, with their importance varying across traits. The output maps reveal spatial patterns of functional composition and diversity that markedly differ from species diversity distributions, highlighting areas of high conservation value and/or functional vulnerability. These findings demonstrate new opportunities with satellite embeddings for large-scale mapping, monitoring and understanding of functional biodiversity in tropical forests.

The Amaryllidaceae family is a rich source of structurally diverse alkaloids with recognized neuroactive and antiparasitic properties. This study provides the first phytochemical and biological characterization of Pyrolirion boliviense and wild Stenomesson miniatum from Bolivia. Alkaloid extracts from bulbs and leaves were analysed by GC–MS and evaluated for acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and Trypanosoma cruzi inhibitory activities. Thirty-two Amaryllidaceae alkaloids were identified, with P. boliviense exhibiting greater alkaloid diversity (25 compounds) and S. miniatum a higher total alkaloid content (227.86 vs. 138.92 μg Gal/100 mg DW). P. boliviense bulb extracts showed the strongest cholinesterase inhibition (AChE IC₅₀ = 6.07 ± 0.47 μg·mL⁻¹; BuChE IC₅₀ = 30.93 ± 1.17 μg·mL⁻¹), whereas S. miniatum extracts displayed weaker AChE inhibition and no detectable BuChE activity. In anti-T. cruzi assays, bulb extracts were the most active, with S. miniatum showing an IC₅₀ of 0.90 ± 0.15 μg·mL⁻¹ (SI = 20.12) and selective anti-amastigote activity (IC₅₀ = 1.42 ± 0.66 μg·mL⁻¹; SI = 12.77). These findings identify Bolivian Andean Amaryllidaceae as promising sources of bioactive alkaloids with potential applications for Alzheimer’s disease and Chagas disease drug discovery.

The impact of rising temperatures on tropical treeline ecosystems remains understudied. Here we report on the growth history of Polylepis pepei trees growing in Madidi National Park, a tropical forest setting at elevational treeline in the Andes-Amazon ecotone of Bolivia. Using dendrochronological methods, we developed an annually-resolved tree-ring width chronology spanning from 1850 to 2018 CE. To our knowledge this is the longest tree-ring record for this species (168 years). The standardized ring-width chronology revealed a significant radial growth decline after the 1962–1963 growth ring (i.e. 1963–2018). From 1960–2015, smaller ring-widths were associated with drier and warmer conditions during the previous wet season (∼ November–March), while wetter and cooler conditions led to enhanced growth in the following year. P. pepei radial growth decline coincided with a significant increase in minimum temperature and decrease in precipitation and diurnal temperature range that was observed both locally and regionally across tropical South America between 1960–2015. These climate trends at treeline may indicate a reduction in moisture convergence and transport to such higher elevation settings in the Andes. If temperatures continue to rise at current rates, P. pepei growth may continue to decline, threatening the survival of tropical treeline ecosystems in Bolivia.

Zygomorphy (bilateral symmetry) is a form of floral specialization that is thought to restrict pollination to fewer visitors, enhancing the effectiveness and precision of pollen transfer between conspecific flowers. In this way, zygomorphy may help the persistence (i.e., decrease extinction) of small and scattered populations, ensuring cross‐pollination even when individuals have few conspecifics nearby. In this study, we use phylogenetic regression models to relate the abundance of 478 Andean species to the zygomorphy of their petals, zygomorphy of their reproductive organs, and shape of their corollas. Our results show that tree abundance correlates with the first trait, but not the last two. Species with zygomorphic petals occur at approximately half the average abundance of non‐zygomorphic species. This pattern is particularly pronounced in species‐rich mid‐altitude forests. Overall, these findings support the idea that the increases in diversification rates found in zygomorphic clades may be due to decreased extinction rates, because these species can persist at lower abundances, rather than (or in addition to) increased speciation rates. More studies that explore zygomorphy in rare species using experimental and phylogenetic methods can help us understand whether and how species loss is avoided.

Plants interact with their environment through diverse specialized metabolites that protect them from abiotic stressors, like drought or radiation, and biotic stressors, like herbivores or pathogens. However, few studies have considered the chemical properties of metabolites as a potential axis of functional trait variation along environmental gradients. Here, we examined how the chemical properties of foliar metabolomes, such as mean aromaticity, hydrophobicity and polarity, as well as commonly used morphological traits, vary with climate and elevation among 16 forest plots in the tropical Andes of Bolivia. We found that chemical properties were weakly related to morphological traits among tree species, yet both varied significantly with climate and elevation. In particular, abundance-weighted mean hydrophobicity decreased, and polar surface area increased with elevation and in colder and drier climates. Additionally, co-occurring species showed increasing chemical similarity with elevation for the most-aromatic and most-polar metabolites. These results suggest that abiotic stress associated with colder, drier climates and solar radiation acts as a filter for metabolome chemical properties. This contrasts with chemical dissimilarity observed at lower elevations, which is likely driven by pressure from host-specialized enemies in warmer, wetter climates. Our results introduce the possibility that chemical defences may be constrained by abiotic stressors.

The bracken fern Pteridium spp. dominates postfire vegetation in tropical montane forests, where fronds, litter, allelopathy, and dispersal limitation hinder forest regeneration. However, this species' effect on soil seed bank remains poorly understood. We investigated the effects of bracken fronds and litter on the abundance, richness, and species diversity of the soil seed bank in a tropical montane fire‐deforested area in Bolivia. At eight study sites (1800–2350 a.s.l), soil samples were collected under five treatments: (a) fronds and litter intact (F + L+), (b) fronds intact and litter removed (F + L−), (c) fronds removed and litter intact (F−L+), (d) fronds and litter removed (F−L−), and (e) forest. Using the seedling emergence method, samples were assessed every 20 days over 8 months (September 2021–May 2022). Compared to intact bracken, forest areas showed 2.6, 1.7, and 1.5‐fold greater abundance, species richness, and diversity of zoochorous species, respectively. Among bracken treatments, abundance, richness, and diversity of zoochorous species decreased by 2.7, 2.6, and 2 times, respectively, when fronds and litter were removed, compared to the intact bracken treatment, but were not significantly different when only litter was removed. Our findings indicate that in bracken‐dominated environments, fronds and litter improve microclimatic conditions, maintaining the viability of zoochorous species in the soil seed bank. The removal of litter without cutting fronds reduces light interception and seed trapping while maintaining zoochorous seed germination capacity in the soil, and might be a better management strategy than removing fronds and litter to promote seedling recruitment from the soil seed bank.

Deforestation leads to non‐forested areas that often need active ecological restoration to promote forest succession. Here, we developed a trait‐based approach to guide the design of restoration projects and tested our approach in tropical areas deforested by fires and dominated by bracken. Deforestation caused by human‐induced fires creates complex conservation problems in tropical areas. After fire, montane tropical deforested areas are often dominated by bracken fern ( Pteridium spp.), which prevents the establishment of many species of trees. This means that effective ecological restoration strategies are needed for forest recovery. We explored whether a trait‐based approach could be used to guide the selection of tree species in active restoration projects in deforested areas. We first tested whether traits could be used to predict which species can overcome bracken‐associated filters. We then tested the relationship between the trait‐based predictions for each species and their abundance in a reference old‐growth forest. To identify key traits, we conducted a seed addition experiment in bracken‐dominated areas that had developed 5–15 years after a fire, using 23 tree species common in the Bolivian montane forests, and monitored seedling establishment, survival and growth for 36 months. We then related seedling performance to the functional traits of adults and seedlings. We found that six functional traits improved tree seedling performance in bracken‐dominated areas, and that only one third of the species evaluated exceed a 25% probability of recruitment. Most of the favoured traits correspond to conservative strategies. The species dispersed by birds and with large seeds were the most likely to overcome the filters created by bracken. Based on the trait predictions, we found that the species predicted to overcome bracken are not common in old‐growth forests. Synthesis and applications . Our results can be used by stakeholders to select the species best suited for active restoration projects in bracken‐dominated areas throughout the tropical region. Furthermore, our trait‐based approach, which considers seedling performance in disturbed areas, can serve as a guide for species selection in restoration programmes in other disturbed systems.

Aim: Effective implementation of the Global Biodiversity Framework and Global Strategy for Plant Conservation depends on accurate species distribution data. Current vascular plant distribution data, while crucial for understanding terrestrial ecosystems, is often sparse and biased and requires significant expansion. This study developed a scalable approach to prioritize areas for plant occurrence data acquisition, adaptable to national priorities and providing a framework for botanical institutions to coordinate efforts and allocate resources. Location: Global. Methods: Using a Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) analysis, we prioritized areas based on: (a) ecosystem service value; (b) floristic value threatened by climate or land-use change; and (c) uncertainty in species richness estimates, stratified by biome and region. Regional prioritization maps for Africa & Madagascar; East, South and Southeast Asia; Siberia and the Russian Far East; South America; and North & Central America were reviewed by botanical experts for validation. Scalability was assessed by comparing regional and global analyses. Results: Data-driven priority maps, divided into tree-dominated and grassland/deforested areas, largely received expert support. High similarity between global and regional maps demonstrated scalability. Main conclusions: Our approach provides a framework for supporting national implementation of the Global Biodiversity Framework. Variables and their weights can be tailored to national or local needs. The method’s flexibility and adaptability extend to other taxonomic groups and objectives, such as protected area selection By prioritizing data acquisition, whether field-based or digital, this research promotes the efficient use of resources. A key advantage of this approach is its capacity to systematically translate expert opinion into explicit and quantitative criteria, which in turn facilitates clear communication with policymakers and funders.

Context . Exploring how Indigenous People interact with plants through their functional traits allows us to understand the ecological bases of plant selection. Functional traits can help explain why certain plants are consistently chosen for specific purposes across diverse cultural contexts. However, these relationships are complex and remain insufficiently explored. Here, we ask (1) which functional traits are most important in shaping different uses? and (2) do similarities in trait–use associations across Indigenous communities reflect patterns of knowledge convergence? Methods . We conducted fieldwork across nine different Indigenous communities spanning a 1800 km distance in western Amazonia. In total, we sampled 115 0.1‐ha plots, recording the abundance of 1856 woody plant species. For these species, we collected data on 13 different functional traits, primarily measured in the field, with additional values sourced from TRY and other databases, and conducted in situ ethnobotanical interviews with 25 Indigenous male participants, focusing on 14 distinct use categories. We analysed (1) trait–use relationships using generalized linear models and (2) the similarity in trait selection for each use across communities using generalized linear mixed models. Results . Plants used for medicine or food were associated with multiple traits, including reproductive traits, exudates and life form. In contrast, culturally specific uses such as rituals, cosmetics or recreational were linked to more specific traits, particularly wood density and lianas. Across communities, we observed widespread convergence in trait–use associations, suggesting shared patterns of plant use despite cultural differences. However, 24% of the trait–use combinations showed divergence, indicating local adaptation or cultural specificity. Synthesis and applications . Plant selection by Indigenous communities is not random; rather, it is guided by functional traits that consistently support human well‐being. We named this pattern ‘functional selection convergence’, highlighting how ecological function and traditional knowledge interact across distinct cultural contexts. This convergence shows the importance of functional ecology explaining traditional plant selection. Our findings are a call for a trait‐based ethnobotanical approach to document and better preserve the ecosystem services essential to Indigenous livelihoods. Nevertheless, we emphasize the need for future research to involve broader and more diverse ethnobotanical participation. Read the free Plain Language Summary for this article on the Journal blog.