Transfer or delegate (power) to a lower level, esp. from central government to local or regional administration
(of duties or responsibility) Pass to (a body or person at a lower level)
Degenerate or be split into
means to gradually go from an advanced state to a less advanced state, or to pass something, such as responsibility or power, from one person or group to another person or group at a lower level of authority.
to transfer from one person to another [v DEVOLVED, DEVOLVES, DEVOLVING]