Purpose: The potential impact of climate change can lead to a reduction of up to 46% in the distribution of ferns within suitable habitats. In this study, we employed predictive models for species distribution to gain insights into the effects of climate change and edapotopographic factors on ferns, anticipating declines in forested environments particularly vulnerable. Material and methods: The research focused on the Neotropical region, from Mexico to Patagonia, including the Caribbean islands, with an emphasis on four fern species. Nineteen climatic and nine edapotopographic variables were used to develop models for both current and future scenarios under different climate conditions. This highlighted the importance of identifying areas at risk to implement effective conservation measures. Results and conclusion: The results illustrate the present distribution of species in the region, while projections for 2070 indicate substantial reductions in suitable habitats under various climate scenarios. The study validates the hypothesis of a decline in forested areas, emphasizing the susceptibility of ferns. Furthermore, it highlights a notable loss of suitability for specific species, such as Lygodium venustum, underscoring the significance of ferns in ecosystems. The uncertainty analysis points out the robustness of the findings, emphasizing the imperative for mitigating carbon emissions and implementing conservation strategies to address forthcoming challenges in biodiversity preservation amid environmental changes.

Ecotones between major biomes represent strong ecological gradients and offer valuable opportunities to investigate the processes structuring biological communities. The ecotone between the Cerrado and the Atlantic Forest is one of the most extensive and biodiverse transition zones in South America. Here, we investigated the assembly processes of bat communities across the Cerrado–Atlantic Forest ecotone, contrasting the predictions of environmental filtering, competitive exclusion, and neutral assembly using a coevolutionary community assembly framework. We also evaluated how environmental and historical variables influence patterns of phylogenetic beta diversity and tested whether abrupt changes in community composition occur along the gradient from the ecotone towards the core areas of both biomes. We found that environmental filtering was better supported than competitive exclusion and neutral models in structuring bat communities within the ecotone. Variation in phylogenetic beta diversity was primarily explained by environmental variables, particularly precipitation seasonality, annual precipitation, annual temperature range, and canopy height. An abrupt change in phylogenetic beta diversity was detected from the ecotone towards the core of the Cerrado biome, whereas no comparable shift was observed towards the Atlantic Forest, indicating that distinct assembly processes operate along gradients associated with these two megadiverse biomes. Our results highlight the dominant role of environmental filtering in shaping bat communities in the Cerrado–Atlantic Forest ecotone and emphasise the importance of accounting for coevolutionary processes when interpreting community assembly patterns in Neotropical biodiversity hotspots.