Pelage variation and morphometrics of closely related Callithrix marmoset species and their hybrids.

BACKGROUND: Hybrids are expected to show greater phenotypic variation than their parental species, yet how hybrid phenotype expression varies with genetic distances in closely-related parental species remains surprisingly understudied. Here, we investigate pelage and morphometric trait variation in anthropogenic hybrids between four species of Brazilian Callithrix marmosets, a relatively recent primate radiation. Marmoset species are distinguishable by pelage phenotype and morphological specializations for eating tree exudates. In this work, we (1) describe qualitative phenotypic pelage differences between parental species and hybrids; (2) test whether significant quantitative differences exist between parental and hybrid morphometric phenotypes; and (3) determine which hybrid morphometic traits show heterosis, dysgenesis, trangression, or intermediacy relative to the parental trait. We investigated cranial and post-cranial morphometric traits, as most hybrid morphological studies focus on the former instead of the latter. Finally, we estimate mitogenomic distances between marmoset species from previously published data. RESULTS: Marmoset hybrid facial and overall body pelage variation reflected novel combinations of coloration and patterns present in parental species. In morphometric traits, C. jacchus and C. penicillata were the most similar, while C. aurita was the most distinct, and C. geoffroyi trait measures fell between these species. Only three traits in C. jacchus x C. penicillata hybrids showed heterosis. We observed heterosis and dysgenesis in several traits of C. penicillata x C. geoffroyi hybrids. Transgressive segregation was observed in hybrids of C. aurita and the other species. These hybrids were also C. aurita-like for a number of traits, including body length. Genetic distance was closest between C. jacchus and C. penicillata and farthest between C. aurita and the other species. CONCLUSION: We attributed significant morphometric differences between marmoset species to variable levels of morphological specialization for exudivory in these species. Our results suggest that intermediate or parental species-like hybrid traits relative to the parental trait values are more likely in crosses between species with relatively lesser genetic distance. More extreme phenotypic variation is more likely in parental species with greater genetic distance, with transgressive traits appearing in hybrids of the most genetically distant parental species. We further suggest that fewer developmental disturbances can be expected in hybrids of more recently diverged parental species, and that future studies of hybrid phenotypic variation should investigate selective pressures on Callithrix cranial and post-cranial morphological traits.

Antibodies Against Henipa-Like Viruses in Brazilian Bats.

Bats are reservoir hosts for many paramyxoviruses, some of which cause human and zoonotic diseases of public health importance. We developed a Nipah virus nucleoprotein enzyme-linked immunosorbent assay to detect cross-reactive antibodies in serum samples from several bat species in Brazil. Our results warrant further investigation of henipa-like virus reservoirs in the Western hemisphere.

Diversity and abundance of mosquitoes (Diptera:Culicidae) in an urban park: larval habitats and temporal variation.

Urban parks are areas designated for human recreation but also serve as shelter and refuge for populations of several species of native fauna, both migratory and introduced. In Brazil, the effect of annual climate variations on Aedes aegypti and dengue epidemics in large cities like São Paulo is well known, but little is known about how such variations can affect the diversity of mosquito vectors in urban parks and the risk of disease transmission by these vectors. This study investigates the influence of larval habitats and seasonal factors on the diversity and abundance of Culicidae fauna in Anhanguera Park, one of the largest remaining green areas in the city of São Paulo. Species composition and richness and larval habitats were identified. Seasonality (cold-dry and hot-rainy periods) and year were considered as explanatory variables and the models selection approach was developed to investigate the relationship of these variables with mosquito diversity and abundance. A total of 11,036 specimens from 57 taxa distributed in 13 genera were collected. Culex nigripalpus, Cx. quinquefasciatus and Aedes albopictus were the most abundant species. Bamboo internodes and artificial breeding sites showed higher abundance, while ponds and puddles showed greater richness. Significant relationships were observed between abundance and seasonality, with a notable increase in the mosquitos abundance in the warm-rainy periods. The Shannon and Berger-Parker indices were related with interaction between seasonality and year, however separately these predictors showed no relationship with ones. The increased abundance of mosquitoes in warm-rainy months and the fact that some of the species are epidemiologically important increase not only the risk of pathogen transmission to people who frequent urban parks but also the nuisance represented by insect bites. The findings of this study highlight the importance of knowledge of culicid ecology in green areas in urban environments.