Evolution in the spiritual sense is the opening out to a new and better state of being.
Psychological / emotional perspective: To experience evolution in dreams is to be part of a process of growth.
To evolve is to progress from one stage of existence to another.
The whole process of dreaming could in itself be said to be a process of evolution, particularly when we dream in series.
Material aspects: Dreaming of evolution and its associated issues such as the natural development of flora and fauna can be a way of reminding ourselves of the steps needed to develop a project from start to finish.