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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 multifocal 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.

The colorful heliconiine butterflies are distasteful to predators due to their content of defense compounds called cyanogenic glucosides (CNglcs), which they biosynthesize from aliphatic amino acids. Heliconiine larvae feed exclusively on Passiflora plants where ~30 kinds of CNglcs have been reported. Among them, some CNglcs derived from cyclopentenyl glycine can be sequestered by some Heliconius species. In order to understand the evolution of biosynthesis and sequestration of CNglcs in these butterflies and its consequences for their arms race with Passiflora plants, we analyzed the CNglc distribution in selected heliconiine and Passiflora species. Sequestration of cyclopentenyl CNglcs is not an exclusive trait of Heliconius, since these compounds were present in other heliconiines such as Philaethria, Dryas and Agraulis, and in more distantly related genera Cethosia and Euptoieta . Thus, it is likely that the ability to sequester cyclopentenyl CNglcs arose in an ancestor of the Heliconiinae subfamily. Biosynthesis of aliphatic CNglcs is widespread in these butterflies, although some species from the sara‐sapho group seem to have lost this ability. The CNglc distribution within Passiflora suggests that they might have diversified their cyanogenic profile to escape heliconiine herbivory. This systematic analysis improves our understanding on the evolution of cyanogenesis in the heliconiine– Passiflora system.

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 ¼ 26) and central (n ¼ 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 (F ST ¼ 0.049, P ¼ 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. Ó 2014 The Wildlife Society.

Aim Closely related species are expected to be similar in their ecological attributes. However, clades colonizing new environments and diversifying due to ecological processes often show morphological and ecological divergence. Canids arrived in South America after the formation of the Isthmus of Panama and diversified to occupy a variety of habitats. We test whether the diversification of this group was followed by divergence in species niches. If ecological processes are associated with species divergences, we expect to see species occupying distinct climatic niches, showing divergent phenotypes, and showing a close association between their phenotypes and ecological attributes. Location South AmericaMethods We use comparative and multivariate climatic niche analysis, geometric morphometric (skull and jaw), and distance-based phylogenetic regressions to test whether the diversification of South American canids was followed by divergence in their climatic niches and phenotypic traits. ResultsWe found a pattern of continental niche occupancy (north to south) along a complex climatic gradient. As species diverged, they evolved distinct climatic tolerances. Climatic niche similarities are not related to species phylogenetic relationships, indicating that closely related species may have distinct climatic tolerances. Our morphological analysis also showed strong phenotypic divergence between species. Our results suggest that these differences were related to climatic and trophic niches. Results show divergent phenotypes in both the skull and jaw, and that there is a close association between phenotype and ecological strategies.Main conclusions Our study integrates phylogenetic history, ecological and morphological data to study the evolution of South American canids. Canid colonization of South America was followed by species ecological divergences. Our results support the hypothesis that ecological processes are the main drivers of diversification of this clade and illustrate a complex biogeographical history of ecological diversification of canids at continental scale.

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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.