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Carnivora species present specialisations for carnivorous diet, although their dietary spectrum is variable: some are strictly carnivorous, others feed mostly on plants. Knowledge about Carnivora feeding habits and resource use patterns is the basis for understanding ecological dynamics, including their role in ecosystems, trophic interactions and conservation.We aimed to contribute to the identification and description of the trophic guild structure of Carnivora species throughout the Neotropical Region and explore the main drivers behind their structuring.We compiled Carnivora dietary studies and evaluated trophic guild formation through network analysis, diet dissimilarity and overlapping. We investigated whether there is spatial variation in diet parameters and the role of phylogeny in trophic guild structuring.We found dietary studies for 32 species from six Carnivora families. We observed two important biases: most studies focus on large‐bodied felids and canids and were predominantly conducted in South and South‐eastern regions of South America. Additionally, it has been noted that biomes such as the Amazon and Caatinga require further research on dietary studies.The network patterns evidenced that central items in carnivorans' diet are small mammals, plants, arthropods and crustaceans. Modularity suggests grouping generalists/opportunists, marine‐based, plant‐based and two mammal‐based diets. Most opportunistic and generalist species were found within the families Canidae and Procyonidae, while felids were strictly carnivorous.Dietary parameters reveal carnivorans tend to maintain niche breadth regardless of the ecoregion, possibly by substitution of items in their diet. Finally, we observed that phylogeny is an important driver of dietary patterns, indicating that evolutionary history explains part of the habits of carnivores. Our review provides insights to identify broad‐scale patterns and guidelines for new studies. [ABSTRACT FROM AUTHOR]

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While environmental alterations have made Homo sapiens the hyperkeystone species of the globe, biotic homogenization initiated a new era, the "Homogenocene." Still, some terrestrial and aquatic ecosystems in South America are considered pristine and wild, which can lead to a general faith that economic progress is consistent with conservation strategies, even without scientific support. We compiled anthropogenic threats to fish biodiversity in a hierarchical meta‐analysis, along with an evidence synthesis of threats related to biological invasions, based on peer‐reviewed research with the aim to represent the actual conservation status of the South American ichthyofauna. We highlighted human‐related threats and synergistic effects of biological invasions, climate change, environmental alterations (e.g., pollution, aquaculture and damming) and fisheries. Considering measures that reinforce novel alien fish (e.g., artificial hybrids or genetically modified) introductions, it became clear why an eventual increase in local or regional species richness is not always beneficial to aquaculture, biodiversity, human well‐being or nature. In fact, citizens in all societal roles, including scientists, should revise their concepts about threats to fish biodiversity. Environmental policies require more than taxonomic diagnostics to achieve conservation goals under an incompatible scenario of a multiplying number of fish species and biotic homogenization. We advocate for countries in South America using science‐based strategies useful to maintain their social and economic growth along with their "remaining nature." We live a crucial moment when the government overlooks threats to biodiversity and uses agribusiness as the most acceptable manner of fuelling the economy. [ABSTRACT FROM AUTHOR]

Several dozen fish species have been introduced into Neotropical waters, causing significant biotic changes that include deterministic predation interactions with ecosystem effects. In general, reservoirs are preferred over lakes as places for stocking policies, due to their artificial aspect, consequently promoting fish introductions. In a meta‐analytic approach, we compared the biomass of plankton‐feeding (and top predators) with bottom‐feeding fish species between reservoirs and lakes, considering the influence of invaders and trophic levels. Among the 26 ecosystems (12 reservoirs and 14 lakes), there is a dominance of non‐native bottom‐feeding species in artificial environments. We revealed a mechanism behind this dominance in a study case, a tendency for trophic downgrading and biotic homogenization based on interactions between an expatriate invasive centrarchid (sunfish family) predator from North America (the largemouth bass Micropterus salmoides) and two omnivorous cichlids from Africa in novel environmental contexts in Brazil (the benthification process). Both juvenile and adult largemouth bass are keystone predators in aquatic food webs in both their native and introduced ranges. The omnivore–detritivore tilapiines Oreochromis spp. and the phytophagous–omnivorous Coptodon spp. are species that exhibits strong generalist tendencies. Such species feed on the omnivore and detritivore compartments, enhancing detritus cycling among a large variety of δ13C sources. Since their consumption is disproportionate, facilitation of other species occurs with multiplicative effects in the environment. Interactions between invasive species, that is, when an invasive predator (bird, fish, or invertebrate) eats an invasive prey (mainly fish and invertebrates), can serve to highlight biotic homogenization on fresh waters. [ABSTRACT FROM AUTHOR]

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.