Coevolution is a phenomena where two related species evolve at the same time since they share a close relation. For instance, the relation between a predator as its prey or a virus and its hostage. This phenomena helps to predict protein structures, since by revealing the higher order structure of a protein we can predict the structure of other protein that have coevolved with it. This has been used in several studies, such as one 2015 study of Pandini and collaborators entitled "Coevolved Mutations Reveal Distinct Architectures for Two Core Proteins in the Bacterial Flagellar Motor".
The SYMPATHETIC nervous system prepares the body to expend energy whereas the PARASYMPATHETIC nervous system allows the body to restore and conserve energy
