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We evaluated the flammability of leaves based on their shape and size using a single species. Rectangular and triangular shapes showed high flammability that did not vary with size, while circular shapes had minimal flammability, but this varied with size. These findings indicate that leaf shape and size impact flammability.

Land use and cover in urban and rural landscapes change biotic communities, impacting ecosystem services provided by pest predators, which can lead to the overabundance of herbivorous insects and, consequently, increased herbivory, especially in highly urbanized areas. To investigate this, we placed 2555 artificial sentinel prey in 73 sampling units in the Greater João Pessoa region, Northeast Brazil, covering different types of urban and rural landscapes to verify how differences in land use and cover in a tropical city may affect predation on herbivorous caterpillars. Urban landscapes were located within the urbanized perimeter of the city. Rural landscapes included areas with monocultures, small livestock farmers, and smallholder farmers, and were noncontiguous. Arthropods emerged as the primary group controlling herbivorous insect populations, but built-up land cover and fragmented habitats strongly affected this ecosystem service. Birds were the second most common taxon providing pest control and were not affected by differences in land use and cover. Although rural areas were far apart and differed in land cover, predation rates were similar between each other. Contrary to our prediction, temporary plantations did not impact predation rates, probably due to the presence of small forest fragments. Birds might play a key role in controlling herbivorous insects in tropical cities since they can forage over considerable distances and endure highly built-up landscapes. While there is no one-size-fits-all solution to improve habitats for pest control providers, urban planners should aim to increase the number of trees in streets and plazas to encourage the presence of predators.

Biogeographic knowledge of Amazonian amphibians is limited by spatial and temporal coverage, resulting in biases that affect the understanding of their diversity patterns. This study analyzed a database of 951 species based on 213,072 georeferenced occurrence records distributed across 24,319 locations in the Amazon. The objective was to identify sampling biases related to infrastructure and accessibility predictors. The overall results indicate that rivers are the primary drivers of amphibian sampling, while roads had a limited influence, reflecting the historical reliance of the region on river transport. Regarding infrastructure, both cities and hydroelectric plants had a moderate effect on sampling, whereas transmission lines had a negligible effect. However, with the expansion of hydroelectric projects from the mid-1970s onwards, intensifying after 2008 with the Brazilian government's Growth Acceleration Plan (PAC), the high volume of records obtained from these ventures distorted the sampling pattern, overestimating rivers and hydroelectric plants while underestimating highways as a source of sampling bias. We conclude, therefore, that amphibian sampling in the Amazon exhibits significant geographic and temporal bias due to unevenly distributed research efforts, which are largely constrained by logistical challenges and inadequate infrastructure. To overcome these challenges, it is necessary to promote collaboration between researchers and decision-makers, invest in research infrastructure, and improve data dissemination. Additionally, we emphasize the importance of conducting a rigorous preliminary evaluation of datasets, particularly when a substantial volume of data are rapidly generated by infrastructure projects such as hydroelectric power plants, to prevent analytical biases and ensure accurate results. These measures aim to strengthen amphibian research and support biodiversity conservation, particularly in response to increasing deforestation and climate change in the Amazon.

Tropical soil seed banks under isolated trees in pastures remain relatively understudied despite their important role in forest regeneration. Here, we investigated patterns of plant species diversity, abundance, and composition in the soil seed banks of cattle pastures, under fleshy-fruited, and nonfleshy-fruited trees within pastures, and in secondary forest patches at ten study sites in Brazil. We also examined how the fruit traits of isolated trees affected seed bank communities, predicting that fleshy-fruited trees are more connected to frugivory and seed dispersal networks than trees without fruit resources, and would therefore have richer seed banks. We found that the species richness and diversity of seed bank communities were higher in secondary forest patches and under fleshy and nonfleshy-fruited trees compared to soil samples from open pastures, although early successional plants were dominant across all habitats. The fruit traits of isolated trees also affected the richness of seeds dispersed by animals and abiotically. Seed banks under fleshy-fruited trees had more seeds of bird-dispersed plants compared to nonfleshy-fruited trees. Overall, our results show that soil seed banks under isolated trees are more similar to those in secondary forest patch seed banks, especially trees bearing attractive fruit resources that likely increase connectivity to frugivory and seed dispersal networks active in fragmented landscapes.

As tropical biology continues to grow in international participation and cultural diversity, it becomes increasingly important to be attentive to ensuring that our professional spaces are welcoming, respectful, and safe for all members. The Association for Tropical Biology and Conservation (ATBC) supports safe, respectful spaces, contributing to creative and innovative thinking, allowing for diverse solutions and growth. Beyond its Diversity, Equity, and Inclusion Committee, the organization has also formalized codes to establish fundamental norms that protect members from harassment and other misbehaviors. This document is the product of a collective effort, testifying to the commitment of ATBC members to constructing a complete code. In 2019, Krista McGuire, chair of the DEI committee until the beginning of 2020, developed the first draft of the Code of Ethics. This document was employed as a basis for the next DEI committee to start developing a Code of Conduct in April 2020. The Code of Conduct is meant to establish the best practices for everyone to have safe spaces and to serve as a guideline for the expected behavior of a person who participates in any activity organized by the association (in-person or virtual). The code went through multiple rounds of revision by the DEI committee and the Association Leadership, was approved by the ATBC Council in 2022, and shared publicly during the ATBC 2022 in Cartagena, Colombia. By publishing the code in Biotropica, we aim to make the ATBC Code of Conduct more broadly available so other institutions and associations can use it as inspiration to strengthen their own policies. This code highlights conduct expected to maintain professional integrity, enhance cultural sensitivities, and contribute to the collective effect of tropical biology and conservation.

Habitat fragmentation affects metapopulation dynamics by reducing patch (discrete area occupied by a local population) size and connectivity, but its long-term genetic consequences are confounded by species-specific traits and limitations of sequencing techniques. Studies of terrestrial plants with relatively short generation times, combined with high-throughput sequencing, provide valuable insights into the demographic and genetic effects of land-use change. We integrate long-term censuses and genotyping data from epiphyllous bryophyte metapopulations in experimentally fragmented Amazonian forests. We focused on two bryophyte species with contrasting mating systems across 11 populations in small (1- and 10-ha) and large (100-ha and continuous) habitats. We aim to assess how long-term reductions in colony numbers in small fragments affect population genetic diversity and differentiation compared to larger habitats. We also explore how species' mating systems influence migration patterns across forest sites, with bisexual species expected to exhibit a higher likelihood of sexual reproduction and spore output than their unisexual counterparts. Our results reveal contrasting patterns of genetic structure between the two species, with no consistent effects of forest fragmentation detected across the landscape. The bisexual species showed notably lower genetic diversity and slightly higher differentiation in small fragments, suggesting a non-equilibrium metapopulation driven by limited migration. In contrast, the unisexual species exhibited minimal genetic impact from fragmentation, maintaining symmetrical migration among fragments regardless of size, indicative of patchy metapopulation dynamics. This study highlights how contrasting mating systems in epiphyllous bryophytes influence migration patterns and underscores the species-specific responses to habitat fragmentation.

The impact of land use changes on pollinator diversity can vary depending on factors such as the size of remaining natural habitat patches, the type and intensity of anthropogenic activities, and the functional composition of pollinator communities. This understanding is particularly crucial for mangrove ecosystems, which are critically endangered by human activities and prioritized in global conservation strategies. This study investigates how anthropization affects mangrove pollinator diversity by examining how pollinators with different functional traits respond to variations in mangrove patch size and anthropogenic changes in the surrounding landscape matrix. We found that overall pollinator abundance, richness, and diversity increased in smaller mangrove patches, potentially helping to mitigate negative effects such as inbreeding and genetic drift—common in naturally patchy and isolated mangrove populations. However, these pollinator metrics declined with increasing landscape anthropization, with notably lower values in urbanized landscapes compared to agricultural ones, despite the smaller patch sizes in more anthropized settings. This negative trend was consistent across pollinators with varying traits, though the magnitude of the effect differed among pollinator groups. Ground-nesting and exposed-nesting pollinators were most influenced by patch size, while lepidopterans and wasps, as well as species with either very small or large body sizes, solitary behavior, and nesting in exposed sites or cavities, were most affected by landscape anthropization. Conservation and management efforts should prioritize habitat provisioning for these most impacted groups to support mangrove ecosystem resilience.