ICB - Artigos publicados em periódicos

URI Permanente para esta coleçãohttp://200.137.215.59//handle/ri/1399

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Multi-biomarker responses to pesticides in an agricultural population from Central Brazil
(2021-02) Ramos, Jheneffer Sonara Aguiar; Pedroso, Thays Millena Alves; Godoy, Fernanda Ribeiro; Batista, Renata Elisa; Almeida, Frankcione Borges de; Francelin, Carolina; Ribeiro, Francis Lee; Parise, Michelle Rocha; Silva, Daniela de Melo e
We evaluated farmworkers exposed to pesticides and individuals with no history of occupational exposure to pesticides. It was performed the comet assay to evaluate DNA damage. The immunophenotyping of TCD4+ lymphocyte subpopulations in peripheral blood was performed by flow cytometry. The single nucleotide polymorphisms (SNPs) in PON1, XRCC1, IL6, IL6R, TNF-α, and MIR137 genes were evaluated by real-time PCR. The exposed group was composed mostly by males (69.44%), with direct exposure to pesticides (56%) and with an average age range of 46 ± 13.89 years, being that 58.3% of farmworkers directly exposed to pesticides and reported the full use of personal protective equipment (PPE). DNA damage was greater in the exposed group (p < 0.05), reinforced by the use of PPE to denote a lower degree of DNA damage (p = 0.002). In this context, in the exposed group, we demonstrated that the use of PPE, age, gender and intoxication events were the variables that most contributed to increase DNA damage (p < 0.0001). Besides, the exposed group showed a significant increase in the subpopulations of T lymphocytes CD3+CD4+ (p < 0.05) and CD3+CD4+CD25+ (p < 0.0001) and a significant decrease in CD3+CD4+CD25-FOXP3+ (p < 0.05). SNPs in the TNF-α (rs361525) gene presented a difference in the genotype distribution between the groups (p = 0.002). The genotype distribution of TNF-α (rs361525) was also positively correlated with the DNA damage of the exposed group (r = 0.19; p = 0.01), demonstrating a higher risk of DNA damage in the farmworkers presenting the A mutated allele. Our findings demonstrate that pesticides can exert various deleterious effects on human health by damaging the DNA as well as by influencing the immune system in the case of both direct or indirect exposure and these issues are associated to age, gender, intoxication and the nonuse of PPE.
Assessment of multiple biomarkers in Lithobates catesbeianus (Anura: Ranidae) tadpoles exposed to zinc oxide nanoparticles and zinc chloride: integrating morphological and behavioral approaches to ecotoxicology
(2022-09) Motta, Andreya Gonçalves Costa; Guerra, Vinicius; Amaral, Diogo Ferreira do; Araújo, Amanda Pereira da Costa; Vieira, Lucélia Gonçalves; Silva, Daniela de Melo e; Rocha, Thiago Lopes
The ecotoxicological risk to vertebrates posed by zinc oxide nanoparticles (ZnO NPs) is still poorly understood, especially in animals with a biphasic life cycle, which have aquatic and terrestrial phases, such as amphibians. In the present study, we investigated whether acute exposure (7 days) to ZnO NPs and zinc chloride (ZnCl2) at three environmentally relevant concentrations (0.1, 1.0, and 10 mg L−1) induces changes in the morphology, chondrocranium, and behavior of the tadpoles of Lithobates catesbeianus (Anura: Ranidae). Tadpoles exposed to both forms of Zn did not undergo any morphological or behavioral changes at the lowest concentrations (0.1 and 1.0 mg L−1). However, the animals exposed to the highest concentration (10 mg L−1) lacked oral disc structures, were smaller in size, had a longer tail, and presented changes in the position and coiling of the intestine and malformations of the chondrocranium in comparison with the control group. This indicates that ZnO NPs and ZnCl2 altered the development of the tadpoles, causing delays in their metamorphosis and even reducing individual fitness. The tadpoles exposed to both forms of Zn at 10 mg L−1 also had reduced mobility, especially in the presence of conspecifics. Based on these findings, we emphasize the importance of studying morphological, skeletal, and behavioral biomarkers to evaluate the toxic effects of metal-based nanoparticles in amphibians.
Bats and pollution: genetic approaches in ecotoxicology
(2022-11) Sotero, Daiany Folador; Benvindo-Souza, Marcelino; Freitas, Renata Pereira de; Silva, Daniela de Melo e
Environmental pollution drives the decline of species and, as flying mammals, bats can be considered to be excellent indicators of environmental quality, and the analysis of genetic biomarkers in these animals can provide important parameters for the assessment of environmental health. This review verifies the trends in pollution research, in particular, the use of genetic markers in the study of bats, based on a literature search of the Web of Science and Scopus platforms. Sixteen publications were identified during the search, which focused on the timeframe between 1996 and March 2022, including investigations of the effects of heavy metals, agricultural pesticides, and radiation. The studies were based primarily on the application of biomarkers for genotoxic analysis, including the comet assay, micronucleus test, and the Polymerase Chain Reaction (PCR). Only 55 bat species have been investigated up to now, that is, 4% of the 1447 currently recognized. In general, bats exposed to polluted environments presented a higher frequency of genotoxic and mutagenic damage than those sampled in clean environments. Given the importance of the diverse ecological functions provided by bats, including pest control, pollination, and seed dispersal, it is increasingly necessary to investigate the damage caused to the health of these animals exposed to areas with high concentrations of contaminants. Although genetic biomarkers have been used to investigate physiological parameters in bats for more than two decades, then, many knowledge gaps remain, worldwide, in terms of the number of species and localities investigated.
How can “my shoes” affect the amphibian health? A study of the toxicity of microplastics from shoe sole (Polyvinyl chloride acetate) on Physalaemus cuvieri tadpoles (Anura, Leptodactylidae)
(2022-10) Araújo, Amanda Pereira da Costa; Luz, Thiarlen Marinho da; Gonçalves, Sandy de Oliveira; Rajagopal, Rajakrishnan; Rahman, Md. Mostafizur; Silva, Daniela de Melo e; Malafaia, Guilherme
More recently, many studies have reported the impacts of microplastics (MPs) on the health of organisms. However, our knowledge of its effects on some vertebrate groups, such as amphibians remains incipient. Thus, we evaluated whether the exposure of Physalaemus cuvieri tadpoles to MPs from shoe soles can induce harmful effects on their health. After 30 days of exposure to different MP concentrations (2 ×105 MP particles/m3 and 4 ×106 MP particles/m3), we noticed that the tadpoles ingested particles with a mean diameter of 148.8 µm and irregular shapes, which accumulated in the intestinal tube. Such accumulation was associated with a lower-body condition index, non-uniformity in the keratinized structures of the jaw sheath, alterations in the intestine position in the abdominal cavity, bowel tube winding condition, and the emergence of dark regions in the intestine like pseudomelanosis. The reduction of superoxide dismutase and catalase activities suggests that MPs have affected the antioxidant system. The minor nitrite production provides evidence that the production of nitric oxide by cells of the intestinal immune system has been affected. In addition, we observed a significant reduction in the size (area, perimeter, and diameter) of MPs after ingestion, which suggests that tadpoles can act as vectors for their dispersal of MPs from shoe soles in the environment. The principal component analysis and integrated biomarker response assessment also confirm that higher MPs concentration induces a more stressful response. Therefore, our study demonstrates that “my sneakers,” while seemingly harmless, can pose a health risk to amphibians.
Toxicity evaluation of the combination of emerging pollutants with polyethylene microplastics in zebrafish: Perspective study of genotoxicity, mutagenicity, and redox unbalance
(2022-06) Araújo, Amanda Pereira da Costa; Luz, Thiarlen Marinho da; Rocha, Thiago Lopes; Ahmed, Mohamed Ahmed Ibrahim; Silva, Daniela de Melo e; Rahman, Md Mostafizur; Malafaia, Guilherme
Despite the toxicity of microplastics (MPs) in freshwater fish has been demonstrated in previous studies, their effects when mixed with other pollutants (organic and inorganic) are poorly understood. Thus, we aimed to test the hypothesis that the association of polyethylene MPs (PE-MPs) to a mix of emerging pollutants induces more adverse genotoxic, mutagenic, and redox unbalance effects in adult zebrafish (Danio rerio), after 15 days of exposure. Although the accumulation of MPs in animals was greater in animals exposed to PE-MPs alone, erythrocyte DNA damage (comet assay) and the frequency of erythrocytic nuclear abnormalities (ENAs) evidenced in zebrafish exposed to PE-MPs alone were as pronounced as those observed in animals exposed to the mix of pollutant (alone or in combination with MPs), which constitutes the big picture of the current study. Moreover, we noticed that such effects were associated with an imbalance between pro-and antioxidant metabolism in animals, whose activity of superoxide dismutase (SOD) and catalase (CAT) was assessed in different organs which were not sufficient to counterbalance the production of reactive oxygen species [hydrogen peroxide (H2O2)] and nitrogen [nitric oxide (NO)] evaluated. The principal component analysis (PCA) also revealed that while the antioxidant activity was more pronounced in the brain and liver of animals, the highest production of H2O2 was perceived in the gills and muscles, suggesting that the biochemical response of the animals was organ-dependent. Thus, the present study did not demonstrate antagonistic, synergistic, or additive effects on animals exposed to the combination between PE-MPs and a mix of pollutants in the zebrafish, which reinforces the theory that interactions between pollutants in aquatic ecosystems may be as complex as their effects on freshwater ichthyofauna.
Morphological and anatomical evidence support a new wild cassava: Manihot fallax (Crotonoideae, Euphorbiaceae), from Mato Grosso, Brazil
(2017-12) Silva, Marcos José da; Inocencio, Laís de Souza; Sodré, Rodolfo Carneiro; Alonso, Alexandre Antonio
During the preparation of the taxonomic treatment of Manihot in the Midwest Region of Brazil, a new species was found. Manihot fallax M.J. Silva & L.S. Inocencio is described, illustrated and morphologically compared with similar simple-leaved species. The conservation status, geographic distribution (including map), ecology, phenology and notes about leaf anatomy of the new species are given. The synonymisation of M. robusta M. Mend. & T. B. Cavalc. under M. attenuata Müll. Arg. and lectotypes for M. attenuata and M. brachystachys Pax & K. Hoffm are also proposed. An emended description of M. attenuata is proposed as the original description is incomplete as it lacks information on the pistillate flowers, fruits and seeds.
Trends and insights in cytogenetic research in Brazilian anurans: a scientometric analysis
(2025) Silva, Ana Caroline Cândida da; Ramalho, Werther Pereira; Silva, Marco Antonio Guimaraes da; Morais, Alessandro Ribeiro de; Andreani, Tainã Lucas; Mendonça, Maria Andréia Corrêa
Cytogenetic studies are fundamental for understanding species identification, genetic variation, and chromosomal evolution in anurans, which include frogs, toads, and tree frogs. Despite progress, significant gaps remain in the cytogenetic knowledge of these species, particularly in high-biodiversity regions such as Brazil. We conducted a scientometric study using three major databases, focusing on studies of anurans sampled in Brazil. A total of 163 papers reported data for 243 species. Families with the greatest species richness, including Hylidae and Leptodactylidae, were the most studied, whereas Neblinaphrynidae, Eleutherodactylidae, and Ranidae remain uninvestigated. Physalaemus ephippifer, Leptodactylus pentadactylus, L. fuscus, L. macrosternum, Proceratophrys boiei, and Pithecopus rohdei were the most frequently analyzed species. The Atlantic Forest was the most studied region, while the Pantanal, Cerrado, and Pampa exhibited major knowledge gaps. Sampling efforts were largely regionalized. Investment in new cytogenetic techniques has increased over the past decades, but future efforts should focus on underrepresented species, families, and biomes to fill knowledge gaps, advance understanding of chromosomal evolution, and resolve taxonomic uncertainties in Brazilian anurans.
Discovering the richness of Brazilian amphibians and reptiles through images from Instagram profiles
(2025) Ramalho, Werther Pereira; Andreani, Tainã Lucas; Melo, Ana Clara Moreira de; Moreira, Larissa; Morais, Alessandro Ribeiro de
Social media posts can enhance public understanding of biodiversity by promoting species discovery and raising awareness of its importance. Here, we evaluated the representativeness of amphibian and reptile species published on Instagram profiles and discussed the role of social media in publicizing these animals. We analyzed Brazilian profiles that regularly published photos of herpetofauna on Instagram between 2015 and 2021. We identified 1,739 images of 597 amphibian species, mostly anurans, and 2,036 images of 532 reptile species, mostly squamates. The number of images is strongly correlated with the number of amphibian and reptile species featured on Instagram profiles. The species featured in the posts tended to reflect the actual richness of the herpetofauna from Brazil, with a tendency toward species described in earlier taxonomic studies. Endemic and native Brazilian species appeared more frequently, most of which were not classified as threatened. As a result, endangered species were underrepresented in posts, indicating the need for more content highlighting their conservation. These actions, however, should be approached cautiously due to the risks of inadvertently exposing species targeted by the illegal wildlife trade. Finally, we discuss strategies to optimize social media posts to ensure they fulfill their potential in supporting biodiversity conservation.
Predation of Carollia perspicillata (Chiroptera, Phyllostomidae) by South American Pepper Frog (Leptodactylus labyrinthicus): unraveling the predator-prey relationship in caves
(2025) Barbosa, Helbert Sansão; Ramalho, Werther Pereira; Barbosa, Silvana Rodrigues de Sousa; Morais, Alessandro Ribeiro de
Reporting predator-prey interactions is useful for understanding the hunting and defense strategies of the species involved, contributing to reducing knowledge gaps in trophic ecology, behavioral ecology, and natural history. Despite the dietary diversity of anurans, documented cases of anurans preying on bats are rare in the literature, particularly in specific environments such as caves. We present observations on the use of cave habitat and foraging behavior of Leptodactylus labyrinthicus, being the first record of bat predation by this frog in natural conditions. A male L. labyrinthicus was observed making successive leaps until it captured an individual of Carollia perspicillata inside the cave. This is the first recorded instance of a species of Leptodactylus actively preying on bats in full flight. We suggest that in caves with low ceilings, where bats fly close to the ground, species like L. labyrinthicus may benefit from the increased ease of capturing prey. The knowledge of the natural history of these species, especially in terms of behavior and predator-prey relationships, should be further explored, and future studies on niche issues should be approached with a greater level of complexity.
Wallacean shortfall is not reasonable for omitting poorly known species from the climate change agenda
(2026) Moreno, Ana Karolina Mendes; Morais, Alessandro Ribeiro de; Silva, Priscila Lemes de Azevedo; Machado, Iberê Farina ; Terribile, Levi Carina; Ribeiro, Matheus de Souza Lima
Climate change strongly affects species dynamics over spatial and temporal scales and serves as a major driver of future extinction risk. Conservationists have largely assessed the impacts of global warming on species with welldocumented distributions; however, poorly known species have often been excluded from the climate change agenda because of the Wallacean shortfall (incomplete knowledge of species’ geographic distributions). Here, we deconstruct this traditional argument by considering poorly known species in climate change research and proposing an integrative framework to assess their vulnerability by the end of the 21st century. By integrating trait-based and niche modeling approaches, we assessed the climatic vulnerability of seven poorly known anurans in terms of exposure, sensitivity, and adaptive capacity. The results showed that two species were classified as highly vulnerable, whereas three others were classified as potential adapters, potential persisters, or at high latent risk. These findings suggest that historically neglected species may face increasing vulnerability by the end of 2070. The study underscores the need to incorporate poorly known species in future climate change agendas, despite the persistent Wallacean shortfall.
Description of a puzzling new long-legged Pseudopaludicola Miranda-Ribeiro 1926 species (Anura, Leptodactylidae) from the Araguaia river floodplain, Brazil
(2025) Silva, Leandro Alves; Haga, Isabelle Aquemi; Painkow Neto, Ennio; Dantas, Silionamã Pereira; Varago, Amanda; Garda, Adrian Antonio; Kohlsdor, Tiana; Andrade, Felipe Silva de
Twenty-six species are currently assigned to the genus Pseudopaludicola. One of the most conspicuous lineages within this genus corresponds to the long-legged Pseudopaludicola saltica species group, where the three species, Pseudopaludicola jaredi, Pseudopaludicola murundu, and P. saltica, have tibiotarsal articulation extending beyond the tip of the snout. Here, we describe a fourth species belonging to the P. saltica group based on morphologic, molecular, and acoustic evidence. The new species can be distinguished from the other species assigned to the P. saltica group by a yellowish vocal sac in life (grayish vocal sac in P. jaredi and P. murundu and whitish vocal sac in P. saltica). The new species also emits a unique advertisement call compared to other species of the P. saltica group, resembling the rhythm of a galloping horse. This pattern, however, is remarkably similar to that of the distantly related Pseudopaludicola pocoto, suggesting independent evolution in these two species. The new species is described from a single locality in western Tocantins state, Marianópolis municipality (Brazil), in the Araguaia River floodplain. The new taxon described here is the sixth species of Pseudopaludicola known from the Tocantins.
Contrasting anuran communities in Caatinga landscapes: effects of conservation status on species richness and composition
(2025) Zina, Juliana; Silva, André Teixeira da; Oliveira, Angele Tatiane Martins; Sousa, Ana Paula Almeida de; Garda, Adrian Antonio
The Caatinga is a Brazilian biome characterized by irregular rainfall and a hot climate. These environmental conditions play a key role in shaping the structure and organization of biological communities. However, the ecological dynamics of this semiarid region have been largely overlooked, hindering inferences about human impacts on its biological communities. In this study, we assessed the species composition and diversity of anuran assemblages over 18 months in two distinct habitats: inside a Conservation Unit (CU) in the Caatinga (National Forest of Contendas do Sincorá) and within its buffer zone (BZ), the latter affected by agricultural and livestock activities. We compared data from inside and outside the CU and evaluated the effects of conservation status, climatic factors, and different water body types (lakes and streams) on anuran richness and abundance. While 18 anuran species were recorded in the CU, the BZ presented lower richness and a slightly different species composition. Only temperature significantly influenced species richness and abundance in both areas. We suggest that variation in microhabitat structure and human-induced landscape changes could account for the differences in anuran communities. Our findings highlight the urgent need for more scientific studies in the Caatinga.
Integrating biodiversity into climate policy: from ecosystem services to food security in Brazil
(2025) Grelle, Carlos Eduardo de Viveiros; Vieira, Cecília Rodrigues; Colli, Guarino Rinaldi; Magnusson, William Ernest; Garda, Adrian Antonio; Overbeck, Gerhard Ernst; Bergallo, Helena de Godoy; Akama, Alberto; Diniz Filho, José Alexandre Felizola; Juen, Leandro
. Biodiversity and food security are often perceived as conflicting objectives, yet they are deeply interdependent through ecological processes. Biodiversity regulates soil quality, water, climate dynamics and ecological processes—such as pollination—thereby influencing food security, economic development, and resilience to climate risks. In Brazil, the conservation of ecosystems and pollination services exemplify how biodiversity underpins key agricultural commodities such as soy and coffee. Aligning biodiversity conservation with climate policy is therefore crucial, particularly in megadiverse countries that are major commodity producers. With COP30 taking place in Brazil, there is a unique opportunity to integrate biodiversity into global climate agendas, strengthen governance and legislation, and attract investment through sustainable frameworks. This perspective emphasizes that protecting biodiversity is not only an environmental priority but also a strategic pathway for food security, climate resilience, and sustainable economic development.
Landscape and microhabitat structure dictate lizard diversity in semiarid in Caatinga
(2025) Oliveira, Alan Filipe de Souza; Lion, Marília Bruzzi; Venticinque, Eduardo Martins; Garda, Adrian Antonio
Species abundances and richness are central parameters in ecology and crucial for describing diversity and composition across environments. Understanding how they vary in natural environments is critical for informed conservation decisions, especially in the face of anthropogenic pressures, such as deforestation and climate change. We evaluate the influence of landscape and local habitat variables on the richness and abundances of lizards in the Caatinga, the largest continuous block of seasonally dry tropical forests. We sampled seven lizard communities for three months using visual encounters along transects. We recorded landscape and microhabitat variables and evaluated their influence on lizard species richness, diversity, and occurrence using model selection. Ten lizard species were recorded, with Tropidurus semitaeniatus, Ameivula ocellifera, and Tropidurus hispidus being the most abundant. Topographic complexity and the number of rocky outcrops positively affect species richness and diversity by promoting environmental heterogeneity and hence increasing refuges, shelters, and thermoregulation sites. Different microhabitat and landscape variables were important predictors of the occurrences of individual lizard species. The quantity of rocks significantly increased the likelihood of Tropidurus semitaeniatus occurrence, while litter negatively affected Tropidurus hispidus, and fallen logs increased the probability of Ameiva ameiva occurrence. We argue that preserving topographically complex regions is essential for maintaining the diversity of lizards in the Caatinga biome.
Phylogenetic and ecological drivers of dietary preferences in lizards: a comparative analysis
(2025) Cavalcanti, Lucas Barbosa de Queiroga; Pianka, Eric R.; Garda, Adrian Antonio; Costa, Gabriel C.; Colli, Guarino Rinaldi; Vitt, Laurie J.; Chaves, Lucas R.; Rocha, Stéphanie Menezes; Costa, Taís Borges; Duarte, Thainá França de Oliveira; Mesquita, Daniel Oliveira
Investigating how recent and historical factors can mould species traits is crucial for understanding the evolution of biodiversity. We explored lizard dietary preferences, hypothesizing that phylogenetic divergences are correlated with dietary niches, and we examined how they are correlated with ecological and morphological traits. Using data from 751 populations of 347 lizard species, we identified 59 prey categories. Our analyses revealed significant phylogenetic signals in 12 categories, indicating niche conservatism. Phylogenetic principal component analysis indicated that global structure explained 52.5% of the dietary variation, with key prey categories including plants, Formicidae, and Coleoptera. Furthermore, phylogenetic generalized least squares models indicated significant relationships between dietary preferences and climate, foraging mode, habitat type, and body size. Our findings highlight the significant role of niche conservatism, with specific clades exhibiting distinct dietary adaptations. Iguanians primarily consume plants and ants, whereas non-iguanians focus on diverse prey, such as Orthoptera, Araneae, and Blattodea. These patterns are also influenced by ecological factors, such as habitat and climate, underscoring the complexity of ecological interactions. Our study contributes to a deeper understanding of the interplay between evolutionary history, ecological traits, and environmental factors affecting the dietary niches of lizards, emphasizing the need for robust phylogenies in ecological and evolutionary research.
Amphibian sound recordings in Brazil are geographically and taxonomically biased and cover less than two-thirds of native species
(2025) Morais, Alessandro Ribeiro de; Santos, Fábio Hepp Silva Fernandes dos; Pansonato, André; Garda, Adrian Antonio; Campos, Carlos Eduardo Costa de; Santos, Carolina Emília dos; Haddad, Celio Fernando Baptista; Strüssmann, Christine; Silva, Diego José Santana; Nascimento, Luciana Barreto
Recordings of animal vocalizations are useful for behavioural, ecological, and taxonomic studies. Herein, we provide an overview of 15 sound collections in Brazilian institutions housing recordings of amphibian calls. For each collection, we assessed the number of recordings and species with audio files deposited. Based on the 25385 recordings, we provide a list of species, highlighting 26 species with undescribed calls. Hylidae (∼48%) and Leptodactylidae (∼21%) were the two most representative families, probably due to the high number of species described for these families. The number of recordings was not related to the age of the collections. We presume that there are some idiosyncratic features of these collections affecting these numbers, such as the collaborators’ network range and the public system for data input, that are more relevant than the collection age. Body size and geographical range size were strong predictors of the number of recordings available. Interestingly, closely related species had a similar number of recordings in the collections, suggesting a phylogenetic bias in sampling effort. More than 30% of native species are not represented in sound collections. Therefore, we emphasize the need for the creation of new bioacoustics collections, especially with more social engagement to obtain new records in currently underrepresented regions.
Beyond boundaries: rethinking biomes interdependencies in conservation policies
(2026) Roque, Fabio de Oliveira; Ndiribe, Charlotte; Overbeck, Gerhard Ernst; Mello, José Henrique Fortes; Gomes, Mariana Bender; Bergallo, Helena de Godoy; Christofoletti, Ronaldo Adriano; Colli, Guarino Rinaldi; Corbi, Juliano José; Damasceno Junior, Geraldo Alves; Garda, Adrian Antonio
Biomes are fundamental units for biodiversity conservation given their large geographical coverage and pecu- liarities. The interconnectivity among biomes maintains biodiversity and climate patterns at larger spatial and temporal scales. Therefore, treating biomes as isolated entities can undermine the effectiveness of environmental policies and governance towards sustainability goals. In Brazil, for instance, such fractional perspectives could create fragmented or limited understanding of important socio-ecological interconnections among biomes, ul- timately constraining effective conservation strategies and policies. Yet much has been done to integrate Bra- zilian biomes in scientific research or conservation projects, here we portray how the adoption of an integrated view that considers the synergies and interdependencies among biomes is critical for promoting effective con- servation. This is important to ensure the persistence of significant ecological benefits derived from the natural resources of these biomes.
Titanium dioxide nanoparticles as a risk factor for the health of Neotropical tadpoles: a case study of Dendropsophus minutus (Anura: Hylidae)
(2022-03) Amaral, Diogo Ferreira do; Guerra, Vinicius; Almeida, Késsia Laurinho; Signorelli, Luciana; Rocha, Thiago Lopes; Silva, Daniela de Melo e
The production and use of titanium dioxide (TiO2) nanoparticles are increasing worldwide. The release of this substance into the environment can induce toxic effects in aquatic invertebrates and vertebrates, although the exact nature of its impacts on Neotropical amphibians is still poorly understood. In this context, the present study evaluated the toxicity of TiO2 nanoparticles and their counterpart-dissolved titanium dioxide (TiO2)-in the tadpoles of Dendropsophus minutus. The biometric parameters, DNA damage, and behavioral changes were verified in tadpoles exposed to three different concentrations (0.1 mg·L-1, 1.0 mg·L-1, and 10 mg·L-1) of TiO2 nanoparticles and dissolved TiO2 for 7 days. We verified significant DNA damage in the D. minutus tadpoles exposed to both forms of Ti, in comparison with the control group. We also identified a reduction in total size, body length, and width, and the height of the musculature of the tail of the tadpoles exposed to all concentrations of both substances in comparison with the control. In the behavioral test, the tadpoles exposed to nanoparticles and dissolved TiO2 presented reduced mobility and a tendency to be less aggregated than normal. Here, the simultaneous use of multiple biomarkers was fundamental for the reliable assessment of the adverse effects of nanomaterials on anuran amphibians and the establishment of a systematic approach to the biomonitoring of aquatic ecosystems. The present study expands our understanding of the genotoxic, morphological, and behavioral effects of TiO2 nanoparticles and dissolved TiO2 on anuran amphibians, and contributes to the establishment of further research for the more systematic assessment of the environmental risk of nanomaterials.
Genomic data support reticulate evolution in whiptail lizards from the Brazilian Caatinga
(2025) Magalhães, Felipe de Medeiros; Oliveira, Eliana Faria de; Garda, Adrian Antonio; Burbrink, Frank Thomas; Gehara, Marcelo Coelho Miguel
Species relationships have traditionally been represented by phylogenetic trees, but not all evolutionary histories fit into bifurcating divergence models. Introgressive hybridization challenges this assumption by sometimes [or maybe often] leading to mitochondrial introgression, wherein one species’ mitochondrial genome is entirely replaced by another’s (mitochondrial capture). Such processes result in mitonuclear discrepancies, complicating species delimitation and phylogenetic inference. In our study, we used ultraconserved elements (UCE) and mitogenomic data to investigate the evolutionary history of the Ameivula ocellifera complex, a group of South American whiptail lizards widely distributed in semiarid environments of the Caatinga Domain in Brazil. We examine mitonuclear discordances, assessing reticulate evolution, evaluating species limits, and testing for adaptive mitochondrial capture that could explain higher introgression in the mitochondrial genome compared to nuclear DNA. Our findings support the occurrence of an ancient reticulation event during the diversification of these lizards, driven by introgressive hybridization, leading to mitochondrial capture, and explaining mitonuclear discrepancies. Overall, we did not find clear evidence of positive selection across mitochondrial protein-coding genes suggesting adaptive mitochondrial capture of individuals with introgressed mtDNA. Thus, the genetic diversification and mitogenome evolution could be neutral, with selection against hybridization in the autosomal loci only, or even mediated by mitonuclear incompatibilities. Analyses of mtDNA genomes alongside network and species delimitation methods were crucial for identifying and validating individuals with introgressed mtDNA as a distinct species, demonstrating the potential of genome sampling, and using innovative analytical techniques for elucidating speciation processes in the presence of introgressive hybridization.
Amphisbaenians and lizards of the Pernambuco Endemism Center: species richness, sampling gaps, and conservation status in one of the most threatened regions of the Atlantic Forest
(2025) Dubeux, Marcos Jorge Matias; Souza, Ubiratã Ferreira; Lourenço-de-Moraes, Ricardo; Pereira Filho, Gentil Alves; Sales, Raul Fernandes Dantas de; Delfim, Fagner Ribeiro; França, Frederico Gustavo Rodrigues; Freitas, Marco Antônio de; Ávila, Robson Waldemar; Lion, Marília Bruzzi; Garda, Adrian Antonio
In this study, we integrated data from more than 30 years of inventories available in the main herpetological collections of the Pernambuco Endemism Center (PEC), northern Atlantic Forest. We aimed to reduce the Wallacean shortfall of amphisbaenians and lizards (non-snake squamates) in the region, to provide distribution maps of all species, and to direct future survey efforts and conservation strategies in one of the most threatened portions of the Atlantic Forest. The species list was based exclusively on records associated with vouchers from localities in the PEC and transition zones. We recorded 50 species of non-snake squamates in the PEC, distributed across 97 municipalities in four states. Among the species registered in the PEC, seven are topotypical, five are endemic and three are considered threatened with extinction. Only 35% of the municipalities in the PEC have at least one individual deposited in the herpetological collections analyzed and of these only 35% have more than ten species registered. The most representative areas are concentrated in the coastal portion of the PEC, and arranged in four main zones. These zones mainly overlap with areas close to state capitals and around some of the PEC’s protected areas.

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