Karyology of the Atlantic forest rodent Juliomys (Cricetidae): A new karyotype from southern Brazil

Juliomys is a small rodent from the family Cricetidae which inhabits the Atlantic forest and forests from Argentina to eastern Brazil. The three species recognized so far have different karyotypes. In this paper, we describe a new karyotype with 2n = 32, FN = 48 found in Juliomys specimens from a high-altitude area in the Atlantic forest of southern Brazil. The karyotype was analyzed after G- and C-banding and silver staining of the nucleolus organizer regions (Ag-NOR) and its G-banding patterns were compared with those of the newly described species Juliomys ossitenuis (2n = 20, FN = 36). The 2n = 32 karyomorph presented peculiar features and was very different from those of the other species of the genus: J. pictipes (2n = 36, FN = 34), J. rimofrons (2n = 20, FN = 34) and J. ossitenuis (2n = 20, FN = 36). Differences were mostly due to centric and tandem fusions, pericentric inversion and loss of heterochromatin. The karyotype represents a powerful tool to differentiate Juliomys species and our data suggest that the karyotype described herein belongs to a new species

Habitat associations of small mammals in southern Brazil and use of regurgitated pellets of birds of prey for inventorying a local fauna

We inventoried terrestrial small mammals in an agricultural area in southern Brazil by using trapping and prey consumed by Barn Owls (Tyto alba) and White-tailed Kites (Elanus leucurus). Small mammals were trapped in three habitat types: corn fields, uncultivated fields ("capoeiras"), and native forest fragments. A total of 1,975 small mammal specimens were trapped, another 2,062 identified from the diet of Barn Owls, and 2,066 from the diet of White-tailed Kites. Both trapping and prey in the predators' diet yielded 18 small mammal species: three marsupials (Didelphis albiventris, Gracilinanus agilis, and Monodelphis dimidiata) and 15 rodents (Akodon paranaensis, Bruceppatersonius iheringi, Calomys sp., Cavia aperea, Euryzygomatomys spinosus, Holochilus brasiliensis, Mus musculus, Necromys lasiurus, Nectomys squamipes, Oligoryzomys nigripes, Oryzomys angouya, Oxymycterus sp.1, Oxymycterus sp.2, Rattus norvegicus, and Rattus rattus (Linnaeus, 1758)). The greatest richness was found in the uncultivated habitat. We concluded that the three methods studied for inventorying small mammals (prey in the diet of Barn Owls, White-tailed Kites, and trapping) were complementary, since together, rather than separately, they produced a better picture of local richness

Dissecting the parieto-frontal correlates of fluid intelligence: A comprehensive ALE meta-analysis study

Recent advances in cognitive neuroscience have shown how experience-independent cognitive abilities termed fluid intelligence (Gf) can predict academic achievement, longevity and resilience to neurodegeneration. Therefore, the understanding of the neurobiological underpinnings of Gf becomes a crucial step for the implementation of cognitive rehabilitation as well as enhancement interventions. Here we present the result of a quantitative meta-analysis of available fMRI and PET literature about Gf in humans, including (i) distinct maps for verbal and visuospatial stimuli, (ii) an analysis of brain regions contributing to processing of more complex stimuli as well as (iii) a model-driven distinction of processing stages occurring during Gf-related problem solving. Results highlight the loading of Gf components over functionally defined resting-state fMRI networks, with different degrees of overlap in both hemispheres and subcortical structures. A major role for nodes of the dorsal attention network during both verbal and visuospatial abstract reasoning tasks represents the most consistent correlate of Gf, with additional contributions by regions of the anterior salience and left fronto-parietal control network. Increase in trial difficulty elicits a more pronounced engagement of the language and left fronto-parietal control networks, while inferring the rules subtending a given Gf task relies on a different anatomo-functional substrate than producing novel solutions. Current findings might allow a clearer association between Gf-related activity and brain connectivity, also providing quantitative ALE maps to be used in network-based brain stimulation and cognitive training interventions