Maria João Ramos Pereira

Numerous undescribed species face extinction before formal scientific recognition. Despite research advances, the exceptional bat diversity of the Neotropics remains overlooked, with accelerating habitat loss threatening unrecognized lineages with silent extinction, requiring urgent conservation prioritization. Here, we integrate molecular species delimitation, phylogenetic inference, ecological niche modelling, and spatial conservation analyses to identify 95 Neotropical bat lineages that may represent undescribed species within 45 complexes, revealing that at least one-fifth of the recognized taxa may harbor hidden diversity spanning the entire evolutionary spectrum. This overlooked diversity faces a countdown to extinction: 62% of complexes face imminent habitat loss, and most are projected to lose over 50% of their suitable habitat by 2070. At current description rates, formally recognizing this diversity would take decades, a timeframe these putative species cannot afford. We develop a Hidden Species Richness (HSR) Index that pinpoints ten hidden diversity hotspots where undescribed richness coincides with significant human threats and extreme climate vulnerability. These hotspots highlight regions where research efforts are most needed, transforming crises into priorities. This race against extinction requires immediate taxonomic attention to document this biodiversity before it vanishes.

Os incêndios florestais se tornaram um grande desafio ambiental, agravado pelas mudanças climáticas. Embora as tecnologias de sensoriamento remoto tenham avançado, o seu uso para monitorar a frequência e a severidade dos incêndios ainda é limitado, especialmente em regiões com poucos recursos. Para resolver isso, desenvolvemos uma ferramenta de código aberto no Google Earth Engine que gera mapas de regimes de incêndio, combinando dados de frequência e severidade de incêndios. A ferramenta utiliza dados de satélite acessíveis gratuitamente, incluindo o MapBiomas Fogo (1985–2023) e índices de incêndio (NBR, dNBR) da imagem do Sentinel-2A (2019–2023). Aplicada a duas unidades de conservação em savanas brasileiras, a ferramenta revelou regimes de fogo contrastantes: na APA Chapada dos Guimarães, 68% das áreas queimadas apresentaram baixa frequência e baixa severidade, consistentes com a vegetação de cerrado adaptada ao fogo, enquanto regimes de maior intensidade se concentraram nas pastagens; na RPPN SESC Pantanal, 90% da área queimada foi afetada por severidade moderada a alta, fortemente influenciada pelos eventos excepcionais de 2019 e 2020. A ferramenta oferece uma solução de baixo custo, escalável e replicável para monitorar a dinâmica de incêndios, identificar áreas prioritárias para intervenção e apoiar a tomada de decisões em unidades de conservação. Seu caráter de código aberto e o uso de dados satelitais gratuitos democratizam o monitoramento ambiental, tornando-o acessível mesmo em contextos com recursos limitados. Essa abordagem se alinha às estratégias globais de mitigação dos impactos das mudanças climáticas e contribui para iniciativas científicas e políticas voltadas à mitigação de incêndios e ao manejo sustentável dos ecossistemas.

Artibeus fimbriatus, a widely distributed frugivorous bat species in the Neotropics, represents a compelling yet still understudied model for investigating oxidative stress and antioxidant defense mechanisms in a non-traditional mammalian system. This study examined redox balance and organ-specific adaptations in essential organs of A. fimbriatus through an integrated analysis of body mass, organ mass, oxidative stress markers, antioxidant enzyme activities, non-enzymatic antioxidants, and correlation patterns across the brain, heart, kidney, and lung. Our results revealed pronounced organ-specific variation in oxidative stress susceptibility and antioxidant defenses, underscoring ecological relevance and adaptive specialization in frugivorous bats. A comparative analysis with Sturnira lilium further highlighted species-specific differences in redox profiles. These findings advance our understanding of oxidative stress biology and its implications for organismal health, emphasizing adaptive resilience mechanisms in bat physiology.

Over the past 5000 years, the predictable climate seasonality of the Brazilian Cerrado has played a crucial role in shaping the life history strategies of species and the structure of ecological communities of this global biodiversity hotspot. However, this biome is becoming hotter and drier, with a notable lengthening and intensification of the dry season. Declining rainfall results from three key factors: the expansion of the South Atlantic Subtropical Anticyclone, warming of northern tropical Atlantic waters, and reduced evapotranspiration during the dry season due to widespread land conversion. The evapotranspiration drop also plays a pivotal role in regional warming and higher vapor pressure deficit. Climatic change already affects the physiology, phenology, and reproduction of the Cerrado plants, while also driving community‐level alterations, such as woody encroachment and ant–plant–herbivore interaction outcomes. Dry season lengthening is likely to reduce the biomass and alter the dynamics of microbial communities, with negative effects also extending to invertebrates and other groups. The pronounced warming reduces the amount and duration of dewfall, an important water source for insect pollinators and other animals with low vagility during periods of drought. Concerning vertebrates, the most suggested impact is the loss of specialist or endemic species, with restricted distributions, and the expansion of generalist species, lowering the levels of β‐ and γ‐diversity across the region and making communities poorer and more homogenized. In summary, climate change is actively reshaping Cerrado communities, and species' survival will largely depend on their phenotypic plasticity, evolutionary response, and dispersal capabilities. This article is categorized under: Assessing Impacts of Climate Change > Observed Impacts of Climate Change Climate, Ecology, and Conservation > Observed Ecological Changes Trans‐disciplinary Perspectives > Regional Reviews

\firstpage 1 \pubyear2025 \keywordkeyword 1; keyword 2; keyword 3 (List three to ten pertinent keywords specific to the article; yet reasonably common within the subject discipline.) In community ecology, diversity is often operationalized along three dimensions: taxonomic, phylogenetic, and functional. Despite the proliferation of metrics to evaluate diversity, attempts to integrate these facets and to examine the interaction between evolutionary and ecological phenomena neglect the phenotypic diversification process. Through the extrapolation of the phylomorphospace, we introduce a presence-absence framework that measures the trajectory of trait diversification from both alpha and beta perspectives. Trait evolutionary history (TEH) estimates the ancestral phenotype of nodes and its mapping in a functional space links the pathway of trait evolution to species tips, generating functional branches, a variable depicting the amount of trait evolution per phylogenetic branch. Tempo (functional branch length) and mode (lineage density) are decoupled in alpha TEH, while beta TEH only examines tempo. The commonest approach to assess the trait-phylogeny relationship – phylogenetic signal – only quantifies the current statistical (non)dependence between trait and phylogenetic distances, without exploring past circumstances, rates or processes. TEH overcomes this blindspot by measuring the evolutionary pathways of trait diversification among communities, accounting for the interplay between phylogenetic relationships and interspecific trait variation. Biodiversity is the outcome of contemporary-ecological and historical-evolutionary phenomena, and the introduction of TEH represents the next step towards unifying community ecology and macroevolution.

Understanding species responses to environmental changes is vital for effective conservation, especially in vulnerable regions like the Uruguayan Savannah in South America. This study focused on two often overlooked species: the South American coati ( Nasua nasua ) and Molina's hog‐nosed skunk ( Conepatus chinga ). We deployed 90 camera traps across 15 sites in both Brazilian and Uruguayan sectors of the ecoregion to investigate the effects of land cover types (forests, grasslands, farmland and silviculture) and human density on species occupancy. Using occupancy models, we assessed activity patterns and landscape transition histories, generating innovative occupancy maps to inform conservation policies. The South American coati occupancy is positively correlated with forest areas but negatively with grasslands and crop farming ( p < 0.05). In contrast, Molina's hog‐nosed skunk exhibited a positive response to grasslands and crop farming, but a negative response to forests ( p < 0.05). Estimated occupancy for coatis was 0.141 (0.041–0.420), while for skunks, it was 0.377 (0.200–0.610). Coatis were found only in seemingly pristine areas, whereas skunks adapted to previously human‐used areas. Our findings highlight the urgent need for targeted conservation efforts for coatis while recognising the skunk's resilience to landscape alterations. This research provides critical insights for guiding conservation strategies in threatened ecoregions.

Natural history collections serve as crucial infrastructure for both basic and applied scientific research, providing temporal and spatial specimen data needed to understand biodiversity, environmental change, and emerging pathogens. This study surveyed mammal collections across South America to assess the scope and quality of this infrastructure. A detailed questionnaire was distributed to curators and collection managers from May 2021 to February 2022, gathering information on institutional characteristics, collection size, taxonomic and geographical scope, preservation methods, genetic resource availability, percentage digitization, financial support, and challenges such as funding limitations. Our survey identified 141 collections; more than twice the number reported by the American Society of Mammalogists in 2018. South American collections house ∼746 000 catalogued specimens, including 452 primary type specimens, representing only a modest proportion of the vast mammalian diversity of South America. Collections are geographically concentrated in Argentina, Brazil, Colombia, and Peru, with a significant gap in the Guianas region and a decline in responses from Venezuela. The survey highlights four major challenges facing South American collections: staffing shortages, minimal cryogenic infrastructure, incomplete digitization, and sustainability issues. This initiative aims to raise awareness of collections in South America, plan for strategic growth, and strengthen research capacity to address pressing global issues, such as climate change, zoonotic disease transmission, and long-term conservation strategies.

Wildfires have become a significant environmental challenge, exacerbated by climate change. Remote sensing technologies have advanced, but their use for monitoring fire frequency and severity remains limited, particularly in resource-constrained regions. To address this, we developed an open-source tool on Google Earth Engine that generates fire regime maps, combining fire frequency and severity data, thus allowing a temporal assessment of fire severity. The tool utilizes freely available satellite data, including Mapbiomas Fire data (1985-2020) and fire spectral indices (NBR, dNBR) from Sentinel-2A imagery (2017-2023). Our methodology provides high temporal and spatial resolution, enabling continuous analysis of fire patterns over time. It offers a cost-effective, scalable solution for monitoring fire dynamics, identifying areas most impacted by wildfires, and supporting informed decision-making. This capability helps prioritize conservation actions. The main advantages of this approach are its accessibility, adaptability, and processing time. This tool represents a significant advancement in remote sensing for conservation, aligning with global strategies to mitigate the impacts of climate change. It provides a practical, efficient, and replicable solution that not only supports local management efforts but also contributes to broader scientific and policy initiatives aimed at wildfire mitigation and sustainable ecosystem management.