Endothermic animals (i.e., birds and mammals) produce metabolic heat in their bodies in a way that allows them to maintain a near constant body temperature at values that are typically well above ambient temperature. This is an extravagant economy that requires these animals to maintain elevated energy budgets and spend a large part of their resources on basic maintenance. Several endotherms, however, become ectothermic (torpid) as an adaptive strategy to save energy during periods cold periods. However, the fitness-costs of this strategy could be important, as it entails important threats to organs and tissues due to the toxic effects of ROS production during hypoxia and reperfusion. The small South American marsupial, “monito del monte”  "Dromiciops gliroides", known as the missing link between the American and the Australian marsupials, is one of the few South American mammals known to hibernate. Expressing daily torpor and seasonal hibernation (=”opportunistic hibernation”), this species may provide crucial…

What explains the presence of a gene only in the genome of one species and not in any other? Species-specific protein-coding genes, also known as orphans, can arise "from scratch" from previously non-genic loci, through a process known as de novo gene emergence. How exactly the evolutionary transition from non-gene to functional gene unfolds is unclear. Can such de novo emerging genes increase an organism's fitness, and if so how? Orphan genes can also result from extensive sequence divergence of ancestral genes, which can eventually erase all similarity of a gene to its homologues in other species, a process even less well understood than de novo emergence. I will present novel findings which advance our understanding of both these evolutionary mechanisms and bring us a small step closer to a complete picture of the origins of genetic novelty.