Big cat genomes reveal a history of interspecies admixture and adaptive evolution of genes underlying development and sensory perception.

No abstract

Vertical transmission of genomic information does not always offer a complete picture of the evolutionary history of species.Gene trees are often discordant from species trees, and mechanisms leading to discordance, such as hybridization and incomplete lineage sorting (ILS), are missed due to a lack of comprehensive genomic sequences (Bravo et al., 2019;Payseur & Rieseberg, 2016).The advancement of high-throughput whole-genome sequencing technologies and computation efficiency has brought new opportunities for understanding how speciation has happened through-

Annual killifish are among the most remarkable extremophile species with the shortest vertebrate life span. Few studies have reported on the oxidative balance throughout their life cycle and its association to the natural aging process of these neotropical animals in a natural environment. We standardized and analyzed physiological markers related to the redox balance of the annual killifish (Cynopoecilus fulgens) throughout the post-embryonic life cycle (enzyme activity of Superoxide Dismutase, Catalase, Glutathione Peroxidase, and Glutathione S-transferase, as well as the determination of the levels of Lipoperoxidation, Carbonylated Proteins, and Total Proteins). We tested the influence of environmental variables on these biomarkers. Individuals were collected, including juveniles, adults, and seniles, in three sampling units around the Parque Nacional da Lagoa do Peixe, located in the Coastal Plain of Rio Grande do Sul. We observed that males and females used different physiological strategies of their redox balance during their life cycle, and their oxidative balance was influenced by their reproductive period and environmental variables (water temperature, abundance of predators, abundance of another sympatric annual killifish species, and abundance of C. fulgens). The population of each temporary pond presented different physiological responses to the adaptation of their life cycle, and there was an influence of environmental component as a modulator of this cycle. Our study offers reference values that will be useful for comparison in future research with short-lived organisms.

Procambarus clarkii is a freshwater crayfish native to the southern central United States and northern Mexico. In Brazil, it is only present in natural environment in the state of São Paulo. Nutritional and reproductive markers were quantified and characterized, as well as intermediate metabolism and oxidative balance in females of P. clarkii collected in a natural environment over a seasonal cycle. Samples of hemolymph and different tissue were obtained. The degree of gastric repletion presented the highest rates in the spring. An investment in reproduction was detected in the summer, when the energy reserves of the hepatopancreas were mobilized for gonadal maturation, and a higher percentage of mature gonads were observed. In the same period, we observed an increase in lipoperoxidation, despite the increased activity of superoxide dismutase and glutathione S-transferase in muscle and gonads. An increase in the levels of lipoperoxidation and glutathione S-transferase was observed in winter.