Neotropical mustelids: fecal metabolome diversity and its potential for taxonomic discrimination

Chemical profiles of non-invasive biological material,such as feces,have great potential to study elusive animals or those with low population densities.Here,we use a metabolomic approach to evaluate Neotropical mustelids as a biological model to describe the diversity of the metabolites present in fecal samples,as well as to evaluate the potential of chemical profiles for taxonomic discrimination.We collected fecal samples from captive individuals of 5 species of mustelids occurring in Brazil and analyzed them by liquid chromatography coupled to high-resolution mass spectrometry.Over 200 compounds have been annotated;“bile acids,alcohols and derivatives”was the most expressive class in the metabolome of all the species.We successfully discriminated 3 taxonomic groups:1—tayra(Eira barbara);2—otters(Lontra longicaudis and Pteronura brasiliensis;1);and 3—grisons(Galictis vittata and Galictis cuja).Several compounds seemed to be associated with food intake and the digestive process,while others were found for thefirst time in Neotropical mustelids.We concluded that mustelids show high metabolome diversity and that species-specific identification through metabolomic profiles is possible,thus contributing to the development and implementation of additional non-invasive approaches in the study of mustelids.

Seasonal variation and host sex affect bat–bat fly interaction networks in the Amazonian savannahs

Bats are the second-most diverse group of mammals in the world,and bat flies are their main parasites.However,significant knowledge gaps remain regarding these antagonistic interactions,especially since diverse factors such as seasonality and host sex can affect their network structures.Here,we explore the influence of such factors by comparing species richness and composition of bat flies on host bats,as well as specialization and modularity of bat–bat fly interaction networks between seasons and adult host sexes.We captured bats and collected their ectoparasitic flies at 10 sampling sites in the savannahs of AmapáState,northeastern region of the Brazilian Amazon.Despite female bats being more parasitized and recording greater bat fly species richness in the wet season,neither relationship was statistically significant.The pooled network could be divided into 15 compartments with 54 links,and all subnetworks comprised>12 compartments.The total number of links ranged from 27 to 48(for the dry and wet seasons,respectively),and female and male subnetworks had 44 and 41 links,respectively.Connectance values were very low for the pooled network and for all subnetworks.Our results revealed higher bat fly species richness and abundance in the wet season,whereas specialization and modularity were higher in the dry season.Moreover,the subnetwork for female bats displayed higher specialization and modularity than the male subnetwork.Therefore,both seasonality and host sex contribute in different ways to bat–bat fly network structure.Future studies should consider these factors when evaluating bat–bat fly interaction networks.

Modularity and specialization in bat-fly interaction networks are remarkably consistent across patches within urbanized landscapes and spatial scales

Patterns of specialization and the structure of interactions between bats and ectoparasitic flies have been studied mostly on non-urban environments and at local scales.Thus,how anthropogenic disturbances influence species interactions and network structure in this system remain poorly understood.Here,we investigated patterns of interaction between Phyllostomidae bats and ectoparasitic Streblidae flies,and variations in network specialization and structure across Cerrado patches within urbanized landscapes in Brazil and between local and regional scales.We found high similarity in the richness and composition of bat and fly species across communities,associated with low turnover of interactions between networks.The high specialization of bat-streblid interactions resulted in little connected and modular networks,with the emergence of modules containing subsets of species that interact exclusively or primarily with each other.Such similarities in species and interaction composition and network structure across communities and scales suggest that bat-fly interactions within Cerrado patches are little affected by the degree of human modification in the surrounding matrix.This remarkable consistency is likely promoted by specific behaviors,the tolerance of Phyllostomidae bats to surrounding urbanized landscapes as well as by the specificity of the streblid-bat interactions shaped over evolutionary time.

Climatic niche breadths of the Atlantic Forest snakes do not increase with increasing latitude

The climatic niche is a central concept for understanding species distribution,with current and past climate interpreted as strong drivers of present and historical-geographical ranges.Our aim is to understand whether Atlantic Forest snakes follow the general geographical pattern of increasing species climatic niche breadths with increasing latitude.We also tested if there is a tradeoff between temperature and precipitation niche breadths of species in order to understand if species with larger breadths of one niche dimension have stronger dispersal constraints by the other due to narrower niche breadths.Niche breadths were calculated by the subtraction of maximal and minimal values of temperature and precipitation across species ranges.We implemented Phylogenetic Generalized Least Squares to measure the relationship between temperature and precipitation niche breadths and latitude.We also tested phylogenetic signals by Lambda statistics to analyze the degree of phylogenetic niche conservatism to both niche dimensions.Temperature niche breadths were not related to latitude.Precipitation niche breadths decreased with increasing latitude and presented a high phylogenetic signal,that is,significant phylogenetic niche conservatism.We rejected the tradeoff hypotheses of temperature and precipitation niche breadths.Our results also indicate that precipitation should be an important ecological constraint affecting the geographical distribution of snake lineages across the South American Atlantic Forest.We then provide a general view of how phylogenetic niche conservatism could impact the patterns of latitudinal variation of climatic niches across this biodiversity hotspot.