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Rivers, landscape, and climate can alter patterns of gene flow and consequently, shape intraspecific genetic variation. While rivers are predicted to halt gene flow in terrestrial species, they may facilitate migration for aquatic species. Amphibians are usually seen as water-dependent, yet multiple studies have indicated that rivers exert a barrier effect on these organisms. In this study, we investigated the effects of rivers and other abiotic factors, such as climate and geography on genetic variation of a highly aquatic frog (Pseudis tocantins) inhabiting central Brazil. We sequenced fragments of one mitochondrial and two nuclear genes of 179 individuals of P. tocantins from 19 localities along the Tocantins-Araguaia Basin in Brazil and used Generalized Dissimilarity Modeling (GDM) to test the role of rivers, landscape, and climate features on its genetic differentiation. Next, we tested three scenarios of migration along the Tocantins-Araguaia Basin using approximate Bayesian computation (ABC). We found that genetic differentiation among localities is mostly explained by the influence of river connectivity. Conversely, elevation, slope, and past and current climate have little or no impact on genetic differentiation. Furthermore, our results show that patterns of migration took place directionally, from upstream to downstream sites. Rivers have shaped patterns of intraspecific diversity in P. tocantins by acting as the most important facilitator of gene flow. Therefore, we suggest that future research should include the role of rivers as a facilitator of gene flow, especially for those species that are associated with aquatic environments.

Heterologous vaccination against coronavirus disease 2019 (COVID-19) provides a rational strategy to rapidly increase vaccination coverage in many regions of the world. Although data regarding messenger RNA (mRNA) and ChAdOx1 vaccine combinations are available, there is limited information about the combination of these platforms with other vaccines widely used in developing countries, such as BBIBP-CorV and Sputnik V. Here, we assess the immunogenicity and reactogenicity of 15 vaccine combinations in 1,314 participants. We evaluate immunoglobulin G (IgG) anti-spike response and virus neutralizing titers and observe that a number of heterologous vaccine combinations are equivalent or superior to homologous schemes. For all cohorts in this study, the highest antibody response is induced by mRNA-1273 as the second dose. No serious adverse events are detected in any of the schedules analyzed. Our observations provide rational support for the use of different vaccine combinations to achieve wide vaccine coverage in the shortest possible time.

Cetartiodactyla comprises one of the most diverse mammal radiations. Currently, 23 families, 131 genera and more than 330 species are recognized. Several studies have been trying to resolve its phylogenetic relationships. The most comprehensive dated phylogenetic hypothesis available includes only 55% of the extant species, precluding a clear understanding of ecological and evolutionary patterns in Cetartiodactyla. Here, we gathered all mitochondrial genetic data available in GenBank to build a robust Cetartiodactyla calibrated phylogenetic tree using 21 fossil calibration points. We found mitogenomic data for 225 species and included other 93 species from which there was at least one mitochondrial gene available. Using a Bayesian approach, we generated a dated tree comprising 90% of the extant Cetartiodactyla species (n = 318). The major lineages showed robust support and families divergence times are congruent with the available fossil evidence and with previously published phylogenetic hypotheses. By making available a dated phylogeny with extensively sampled clades, we expect to foster future studies on the origin, tempo and mode of Cetartiodactyla diversification.

Ecological requirements and environmental conditions can influence diversification across temporal and spatial scales. Understanding the role of ecological niche evolution under phylogenetic contexts provides insights on speciation mechanisms and possible responses to future climatic change. Large‐scale phyloclimatic studies on the megadiverse Neotropics, where biomes with contrasting vegetation types occur in narrow contact, are rare. We integrate ecological and biogeographic data with phylogenetic comparative methods, to investigate the relative roles of biogeographic events and niche divergence and conservatism on the diversification of the lizard genus Kentropyx Spix, 1825 (Squamata: Teiidae), distributed in South American rainforests and savannas. Using five molecular markers, we estimated a dated species tree, which recovered three clades coincident with previously proposed species groups diverging during the mid‐Miocene. Biogeography reconstruction indicates a role of successive dispersal events from an ancestral range in the Brazilian Shield and western Amazonia. Ancestral reconstruction of climatic tolerances and niche overlap metrics indicates a trend of conservatism during the diversification of groups from the Amazon Basin and Guiana Shield, and a strong signal of niche divergence in the Brazilian Shield savannas. Our results suggest that climatic‐driven divergence at dynamic forest‐savanna borders might have resulted in adaptation to new environmental niches, promoting habitat shifts and shaping speciation patterns of Neotropical lizards. Dispersal and ecological divergence could have a more important role in Neotropical diversification than previously thought., We integrated ecological and molecular data to investigate the relative roles of biogeographic events and niche evolution on the diversification of a lizard genus distributed in Neotropical rainforests and savannas. Our results suggest that dispersal and ecological divergence could have a more important role in Neotropical diversification than previously thought.

A diferença de tamanho corporal entre machos e fêmeas é conhecida como dimorfismo sexual de tamanho (DST). O surgimento do DST é atribuído na maioria das vezes a processos de seleção sexual, entretanto a seleção natural também pode afetar o DST. Tem se observado em diversos grupos que a intensidade do DST está associada com o tamanho corporal das espécies, padrão conhecido como Regra de Rensch. Nós testamos a regra de Rensch na família Cervidae, um grupo com forte dimorfismo sexual. Analisamos o DST de 35 espécies utilizando análises de regressão tipo II (eixo principal reduzido) filogenética (RMA). Ao analisar a relação entre o tamanho dos machos vs o tamanho das fêmeas observamos que o DST se modifica isometricamente com o aumento do tamanho corporal (RMA = 1.05, p = 0.18). Estes resultados evidenciam que a regra de Rensch não se cumpre nos membros da família Cervidae. Na última década, diversos estudos tem mostrado grupos taxonômicos que não seguem a regra de Rensch. Dado que o tamanho corporal está associado com diversas características ecológicas das espécies, é possível que a associação do tamanho corporal com o DST não seja sempre um efeito causal nos grupos que seguem a Regra de Rensch. The difference in body size between males and females is known as sexual size dimorphism (SSD). The existence of SSD is usually attributed to processes of sexual selection, although natural selection can also affect SSD. In some animal groups the extension of SSD is associated with body size, a pattern known as Rensch’s rule. We tested Rensch’s rule in the members of the family Cervidae, a group with strong sexual dimorphism. We analyzed SSD of 35 species by means of phylogenetic reduced major axis regression (RMA). Analyzing the relationships between male size vs female size we observed that SSD changes isometriclly with the increase of body size (RMA = 1.05, p = 0.18). These result evidence that Rensch’s rule does not operate among members of the family Cervidae. In the last decade, many studies have shown diverse taxonomic groups that do not follow Rensch’s rule. Because body size is associated with many ecological characteristics, it is possible that the association of body size with SSD is not always a causal effect in those groups that follow Rensch’s rule. Fil: Amado, Talita Ferreira. Universidad Rey Juan Carlos; España. Universidade Federal de Sergipe; Brasil Fil: Bidau, Claudio Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional de Misiones; Argentina Fil: Zurano, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; Argentina. Universidade Federal Da Paraiba; Brasil Fil: Raimondi, Vanina Belén. Université de Genève; Suiza. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Costa, Gabriel C.. Auburn University; Estados Unidos Fil: Martinez, Pablo Ariel. Universidade Federal de Sergipe; Brasil

Tropical reef fishes show contrasting patterns of karyotypic diversity. Some families have a high chromosomal conservatism while others show wide variation in karyotypic macrostructure. However, the influence of life-history traits on karyotypic diversity is largely unknown. Using phylogenetic comparative methods, we assessed the effects of larval and adult species traits on chromosomal diversity rates of 280 reef species in 24 families. We employed a novel approach to account for trait variation within families as well as phylogenetic uncertainties. We found a strong negative relationship between karyotypic diversity rates and body size and depth range. These results suggest that lineages with higher dispersal potential and gene flow possess lower karyotypic diversity. Taken together, these results provide evidence that biological traits might modulate the rate of karyotypic diversity in tropical reef fishes.

Repetitive DNA varies in nature and abundance, and has had an important role in genome evolution of higher eukaryotes. In the present study we analyzed the dynamics of heterochromatic regions and telomeric sequences in three endemic South American canid species, Chrysocyon brachyurus, Lycalopex gymnocercus, and two subspecies of Cerdocyon thous by means of C-banding and fluorescence in situ hybridization (FISH) with telomeric probes. The three species revealed different banding patterns evidencing amplifications of centromeric heterochromatic and telomeric regions co-localized with telomeric sequences in L. gymnocercus and C. thous, and the presence of a heterochromatic terminal block in the Y chromosome of C. brachyurus. Additionally, an unusual heteromorphism of chromosome pair 1 was observed in the subspecies Cerdocyon thous entrerrianus. Our work emphasizes the importance of cytogenetic studies at the population level comprising the largest possible area of the geographic distribution of the species. Fil: Zurano, Juan Pablo. Parque Ecológico ‘El Puma’. Centro de Rehabilitación y Cría de Animales Silvestres; Argentina Fil: Ojeda, Diego Sebastian. Parque Ecológico ‘El Puma’. Centro de Rehabilitación y Cría de Animales Silvestres; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Bidau, Claudio Juan. Universidad Nacional de Rio Negro. Sede Alto Valle; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Molina, Wagner F.. Universidade Federal do Rio Grande do Norte; Brasil Fil: Ledesma, Mario A.. Parque Ecológico ‘El Puma’. Centro de Rehabilitación y Cría de Animales Silvestres; Argentina Fil: Martinez, Pablo A.. Universidade Federal do Rio Grande do Norte; Brasil

Misiones, Argentina, contains the largest remaining tract of Upper Paraná Atlantic Forest ecoregion; however, ~50% of native forest is unprotected and located in a mosaic of plantations, agriculture, and pastures. Existing protected areas are becoming increasingly isolated due to ongoing habitat modification. These factors, combined with lower than expected regional carnivore densities, emphasize the need to understand the effect of fragmentation on animal movement and connectivity between protected areas. Using detection dogs and genetic analyses of scat, we collected data on jaguars (Panthera onca), pumas (Puma concolor), ocelots (Leopardus pardalis), oncillas (Leopardus tigrinus), and bush dogs (Speothos venaticus) across habitats that varied in vegetation, disturbance, human proximity, and protective status. With MaxEnt we evaluated habitat use, habitat suitability, and potential species richness for the five carnivores across northern-central Misiones, Argentina. Through a multifaceted cost analysis that included unique requirements of each carnivore and varying degrees of overlap among them, we determined the optimal location for primary/secondary corridors that would link the northern-central zones of the Green Corridor in Misiones and identified areas within these corridors needing priority management. A secondary analysis, comparing these multispecies corridors with the jaguar’s unique requirements, demonstrated that this multispecies approach balanced the preferences of all five species and effectively captured areas required by this highly restricted and endangered carnivore. We emphasize the potential importance of expanding beyond a single umbrella or focal species when developing biological corridors that aim to capture the varied ecological requirements of coexisting species and ecological processes across the landscape. Detection dogs and genetic analyses of scat allow data on multiple species to be collected efficiently across multiple habitat types independent of the degree of legal protection. These data used with multi-focal GIS analyses balance the varying degree of overlap and unique properties among them allowing for comprehensive conservation strategies to be developed relatively rapidly. Our comprehensive approach serves as a model to other regions faced with habitat loss and lack of data. The five carnivores focused on in our study have wide ranges, so the results from this study can be expanded and combined with surrounding countries, with analyses at the species or community level. Fil: Dematteo, Karen. Washington University in St. Louis; Estados Unidos. University of Missouri; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rinas, Miguel A.. Provincia de Misiones. Ministerio de Ecología y Recursos Naturales Renovables; Argentina Fil: Zurano, Juan Pablo. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Selleski, Nicole. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina Fil: Schneider, Rosio Gabriela. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina Fil: Argüelles, Carina Francisca. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; Argentina

The bush dog (Speothos venaticus), a small and rarely seen canid from Central and South America, has proven extremely challenging to locate and study in the wild, making the development of species-specific and comprehensive carnivore conservation strategies difficult. From May to August 2011, a detection-dog–handler team located 34 scats from bush dogs in the northern (n = 26) and central (n = 8) zones of Misiones, Argentina. We identified 22 unique genotypes (14 northern and 8 central) and assigned sex to 100% of the genotyped scats. Only half of the scats were located inside 7 protected areas (4 northern and 3 central); the remaining half were located in 4 sites outside of protected areas (3 northern and 1 central). Results suggest low but significant differentiation between zones for bush dogs (FST = 0.049, P = 0.010). Bush dogs demonstrated high habitat-use flexibility and a close association with altered habitat; however, altered habitat may not be optimal for the species because of the potential for lower prey densities and risk of exposure to life threatening diseases by domestic dogs. The effectiveness of noninvasive techniques (detection dogs, genetic analyses of scat, Geographic Information System technology) in studying the ecology of bush dogs not only opens the door for additional studies of a species that has proven difficult to study with standard survey techniques, but also provides an alternative approach that conservationists can use independent of habitat type and presence of humans. © 2014 The Wildlife Society.