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It is well established that several Homo sapiens populations experienced admixture with extinct human species during their evolutionary history. Sometimes, such a gene flow could have played a role in modulating their capability to cope with a variety of selective pressures, thus resulting in archaic adaptive introgression events. A paradigmatic example of this evolutionary mechanism is offered by the EPAS1 gene, whose most frequent haplotype in Himalayan highlanders was proved to reduce their susceptibility to chronic mountain sickness and to be introduced in the gene pool of their ancestors by admixture with Denisovans. In this study, we aimed at further expanding the investigation of the impact of archaic introgression on more complex adaptive responses to hypobaric hypoxia evolved by populations of Tibetan/Sherpa ancestry, which have been plausibly mediated by soft selective sweeps and/or polygenic adaptations rather than by hard selective sweeps. For this purpose, we used a combination of composite-likelihood and gene network-based methods to detect adaptive loci in introgressed chromosomal segments from Tibetan WGS data and to shortlist those presenting Denisovan-like derived alleles that participate to the same functional pathways and are absent in populations of African ancestry, which are supposed to do not have experienced Denisovan admixture. According to this approach, we identified multiple genes putatively involved in archaic introgression events and that, especially as regards TBC1D1, RASGRF2, PRKAG2, and KRAS, have plausibly contributed to shape the adaptive modulation of angiogenesis and of certain cardiovascular traits in high-altitude Himalayan peoples. These findings provided unprecedented evidence about the complexity of the adaptive phenotype evolved by these human groups to cope with challenges imposed by hypobaric hypoxia, offering new insights into the tangled interplay of genetic determinants that mediates the physiological adjustments crucial for human adaptation to the high-altitude environment.

In the wake of European financial market integration, resulting from the elimination of controls on capital movements and the free access given to banks to other domestic markets within the EU, the Italian financial system has undergone a considerable transformation. In the aftermath of these new changes, however, has there been an increase in competition resulting in significant gains for consumers? Or rather, is unification alone, due to imperfections in financial markets, not enough to bring about stronger competition? Utilizing the Rosse-Panzar test, the author analyzes a sample of Italian banks from 1988-96 to evaluate the degree of competition in the industry. The findings suggest that the Italian banking industry operates under conditions of monopolistic competition and that European integration has yet to have a significant impact on industry conduct. However, the Author notes that due to the relative novelty of liberalization its long-term effect can not yet be known. Although the banking industry was far from equilibrium in the years examined, after the initiation of European integration there was a move towards it, however, it has yet to be attained.