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Determinantes de padrões espaciais, ambientais e evolutivos das lacunas hutchinsonianas de serpentes (Squamata: serpentes)

2026-02-11T00:00:00Z

Título: Determinantes de padrões espaciais, ambientais e evolutivos das lacunas hutchinsonianas de serpentes (Squamata: serpentes) Autor(es): Lima, Luiz Antônio Gonzaga de Abstract: Knowledge of the different dimensions of biodiversity is marked by gaps and biases that unevenly affect data availability, being strongly influenced by geographic, historical, and phylogenetic factors. Among these gaps, the Hutchinsonian shortfall—related to the lack of knowledge about tolerance limits to abiotic factors—stands out as particularly relevant in the context of rapid climate change, since the absence of information on thermal tolerance compromises our understanding of species vulnerability, persistence, and future distributions. In this study, we investigated the magnitude of the Hutchinsonian shortfall associated with thermal biology traits of snakes, assessing the distribution and biases of available knowledge across geographic, phylogenetic, and climatic spaces. To this end, we integrated thermal biology data from the literature with spatial, phylogenetic, and environmental analyses. We compiled morphological, physiological, and climatic information from global databases and a systematic review, including data on thermal tolerance, evapotranspiration, and climatic niche under current conditions and future scenarios. Knowledge representativeness was evaluated using niche overlap tests, spatial autocorrelation analyses, and the phylogenetic aggregation index (NRI), in addition to analyses of changes in climatic conditions projected until 2100 under the SSP585 scenario. Our results demonstrate that knowledge of snake thermal biology is limited, strongly biased, and structured across phylogenetic, environmental, and geographic spaces, characterizing a multifaceted Hutchinsonian shortfall. Data are concentrated in a few clades and temperate regions, incompletely representing the group’s climatic niche, particularly for traits associated with minimum thermal tolerance and water balance. This pattern results in extensive portions of climatic space—especially in tropical regions—being systematically underrepresented. Projections of future climate scenarios indicate climatic rearrangements and the emergence of non-analog conditions, increasing uncertainty and limiting ecological inferences and realistic predictions about snake responses to global climate change.

Análise de fatores causais e previsão temporal de acidentes por Bothrops no Brasil

2024-05-06T00:00:00Z

Título: Análise de fatores causais e previsão temporal de acidentes por Bothrops no Brasil Autor(es): Silva, Franciely Fernanda Barbosa da Abstract: nakebite envenomation represents a significant public health challenge, especially in tropical and subtropical developing countries where healthcare systems are precarious, antivenoms are scarce, and warmer climates favor the abundance of snakes. This medical emergency primarily affects impoverished individuals living in rural communities, due to their high exposure to risk areas. Brazil is among the countries with the highest annual occurrence of snakebite cases. In the country, snake species of the Bothrops genus are responsible for most recorded accidents. In Chapter 1 of this dissertation, were employed spatial analyses to identify the determinants of Bothrops snakebite incidence in different regions of Brazil. Across the country, significantly higher snakebite incidence rates were observed in areas with higher percentages of native forest and historical forest loss. Additionally, we found that areas with higher temperatures and precipitation levels in the South, as well as higher climatic suitability for the B. jararaca species in the Southeast, exhibited significantly higher snakebite incidence rates. On the other hand, areas with higher percentages of pasture exhibited significantly lower snakebite incidence rates. In Chapter 2, we employed the Prophet time series model to develop snakebite incidence prediction models for each Brazilian region, considering the influence of covariates on predictive models. The Prophet model proved to be an effective tool in predicting snakebite incidence. We found that the Prophet model integrated with the covariate of maximum temperature in the South, forest fires in the North and Midwest, and a model without covariate integration in the Northeast and Southeast regions, demonstrated the best performance, indicating its potential application in epidemiological surveillance of this public health issue. Understanding the determinants and predicting snakebite incidence can help policymakers, public health authorities, and healthcare professionals develop and implement prevention and mitigation measures, thereby reducing the number of cases and associated adverse impacts.

Composição da paisagem ao longo da distribuição de Callicebus coimbrai Kobayashi & Langguth, 1999 e sua relação com a ocorrência da espécie

2025-08-28T00:00:00Z

Título: Composição da paisagem ao longo da distribuição de Callicebus coimbrai Kobayashi & Langguth, 1999 e sua relação com a ocorrência da espécie Autor(es): Santana, Aline Souza Abstract: Land use and land cover (LULC) changes are among the main drivers of biodiversity decline, promoting habitat loss and fragmentation and affecting the distribution and abundance of organisms. The conversion of natural landscapes into anthropogenic matrices restricts native vegetation to isolated remnants. In this context, arboreal primates are particularly affected due to their essential dependence on forested habitats. Here, we characterized the landscape composition throughout the distribution of Callicebus coimbrai Kobayashi & Langguth, 1999, an Endangered primate endemic to the Atlantic Forest between the São Francisco River and the Recôncavo region of Bahia. We used LULC data from MapBiomas (collection 9) to analyze current (2023), comparative (1985 and 2023), and temporal (1985–2023) landscape composition within the species’ known occurrence and across 65 landscapes at different spatial scales (1 km, 2 km, and 3 km radii). We identified 18 LULC classes within the current distribution of C. coimbrai, with predominance of Forest Formation (21.68%), Pasture (~44%), Mosaic of Uses (15.89%), and Savanna Formation (3.12%). The comparative analysis showed significant differences across all classes (χ² = 175.17, df = 17, p < 0.01), and the temporal analysis revealed conversion of Forest Formation (~50%) and Savanna Formation (37.65%) mainly into Pasture. Significant differences were found for Forest Formation, with higher proportions at 1 km (W = 1778; p < 0.01) and 2 km (W = 1476; p < 0.01) radii; Pasture, with lower proportion at the 1 km radius (W = 691; p = 0.01) compared to the overall distribution mean; Mosaic of Uses, with lower values at 2 km (W = 701; p = 0.02) and 3 km (W = 719; p = 0.02) radii; and Forestry, with the highest values across all classes (p < 0.01). Among spatial scales, significant differences were detected for Forest Formation (H² = 8.78; p = 0.01), Pasture (H² = 7.82; p = 0.02), Forestry (H² = 7.18; p = 0.02), and Urban Area (H² = 27.08; p < 0.01). Our results indicate that forests where the species occurs have been continuously degraded by cattle ranching and agriculture, the main threats to the conservation of C. coimbrai. Forest Formation may be becoming insufficient to ensure the species’ long-term persistence and viability. The historical process of landscape occupation and transformation, although perceptible at broader scales, may not yet fully demonstrate emerging effects but may generate an “extinction debt,” with impacts on C. coimbrai populations in future generations. This study reinforces the need for conservation strategies and may support and guide future management actions.

Autoalelopatia da polpa funicular de um cacto colunar que ocorre em diferentes ecossistemas do Nordeste do Brasil

2025-02-04T00:00:00Z

Título: Autoalelopatia da polpa funicular de um cacto colunar que ocorre em diferentes ecossistemas do Nordeste do Brasil Autor(es): Santos, Bruno de Santana Abstract: The funicular pulp of fruits present in some Cactaceae is known to inhibit the germination of their own seeds. Furthermore, it has been reported in the literature that fruits can produce toxic or deterrent metabolites, often found in higher concentrations and diversities than in other plant organs, thus being able to prevent the germination of their own seeds. However, it has not yet been described in the literature how environmental conditions can influence the dynamics of this autoallelopathic effect. Therefore, the general objective of this dissertation was to evaluate the autoallelopathy of the funicular pulp of a columnar cactus that occurs in different ecosystems of Northeastern Brazil. We used as a study model the species Pilosocereus catingicola (Gürke) Byles & Rowley subsp. salvadorensis (Werderm.) Zappi (Cactaceae), which occurs in areas of Caatinga, a semiarid region of Northeastern Brazil; and in areas of Restinga, in the Brazilian coastal region. Furthermore, this columnar cactus species produces its fruits in the dry and rainy seasons. To achieve the general objective of this dissertation, this work was divided into two chapters. In the first chapter, the objective of the work was to perform the metabolite profile of the mucilaginous funicular pulp of the fruits of P. catingicola subsp. salvadorensis using the non-targeted metabolomics technique by Gas Chromatography coupled to Mass Spectrometry. The results for this chapter, it was possible to note 135 metabolites belonging to 19 chemical families. In addition, it was possible to conclude that environmental conditions directly influence the metabolism of the funicular pulp of the fruits of P. catingicola subsp. salvadorensis in different ecosystems, with the variations observed here being related to seasonality, resulting in differences between populations of the same species. In the second chapter of this dissertation, the objective of the work was to evaluate how seasonality and the ecosystem of occurrence influence the autoallelopathy exerted by the funicular pulp of the fruits of P. catingicola subsp. salvadorensis on the germination behavior of its seeds. The results for this chapter showed that the seeds produced in the rainy season, in both populations, presented higher germinability, shorter germination time and greater synchrony, with less uncertainty and variation in the germination process. However, the extracts of lower polarity (AcOEt and Hex) negatively influenced the germination behavior as the concentrations increased during the rainy season, for both populations. Therefore, we can conclude for this chapter that the effect of autoallelopathy is dynamic in nature, being influenced by the fruit production seasons and the ecosystem in which these populations are inserted. The results found in this dissertation provide a comprehensive view of the metabolic responses of this species to environmental conditions, highlighting its adaptive capacity and the role of seasonal conditions in directing its metabolism. In this context, extractions performed with different organic solvents revealed significant variations in the concentrations of compounds between seasons and populations, demonstrating that seasonality not only regulates metabolic synthesis, but also influences the distribution and predominance of metabolites, adjusting them to the environmental conditions of each period, influencing the autoallelopathic effect differently.