Previous efforts to reconstruct evolutionary history of Palearctic ground squirrels within the genus Spermophilus have primarily relied on a single mitochondrial marker for phylogenetic data. In this study, we present the first phylogeny with comprehensive taxon sampling of Spermophilus via a conventional multilocus approach utilizing five mitochondrial and five nuclear markers. Through application of the multispecies coalescent model, we constructed a species tree revealing four distinct clades that diverged during the Late Miocene.
View Article and Find Full Text PDFPredatory hunting is a complex species-typical behaviour involving different skills, some of which may include learning. This research aims to distinguish between rigid and flexible parts in live-insect hunting behaviour in nine herbivorous and granivorous rodent species, and to find out whether there is room for cognition in this activity. In laboratory experiments, all species studied manifest skilful attacks towards insects in a manner that is typical for specialised predators chasing a fleeing prey.
View Article and Find Full Text PDFThe orbitofrontal cortex (OFC) has been implicated in goal-directed planning and model-based decision-making. One key prerequisite for model-based decision-making is learning the transition structure of the environment-the probabilities of transitioning from one environmental state to another. In this work, we investigated how the OFC might be involved in learning this transition structure, by using fMRI to assess OFC activity while humans experienced probabilistic cue-outcome transitions.
View Article and Find Full Text PDFThe article presents the results of a comparative analysis of different therapy regimens impact on the effectiveness of treatment of patients with early and late rheumatoid arthritis in steady-state. Data on ongoing basis anti-inflammatory therapy of rheumatoid arthritis and the treatment of associated conditions were obtained by continuous copying from case histories of hospital department patients. The observations lasted 12 months.
View Article and Find Full Text PDFUsing knowledge of the structure of the world to infer value is at the heart of model-based reasoning and relies on a circuit that includes the orbitofrontal cortex (OFC). Some accounts link this to the representation of biological significance or value by neurons in OFC, while other models focus on the representation of associative structure or cognitive maps. Here we tested between these accounts by recording OFC neurons in rats during an OFC-dependent sensory preconditioning task.
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