"Imagine a system S of some kind. Suppose there is a way to make a number of copies from it, possibly with variations. Suppose that these systems are united into a new system S' which has the systems of the S type as its subsystems, and includes also an additional mechanism which controls the behavior and production of the S-subsystems. Then we call S' a metasystem with respect to S, and the creation of S' from S a metasystem transition (MST for short)." (Turchin) Now suppose two different types of species (systems) who initially were not connected, build a relationship [e.g. elephants start using horses as a means of transportation ]. Is this a metasystem transition? Or does the underlined sentence suggest otherwise? Do the two systems/species that form a relationship have to be similar and/or have evolved through variation from a similar system?