Here, constant selection will eventually fix the population on the types with the maximal fitness value, or in the case of frequency dependent selection, possible bring the population to a polymorphism where all the types have the same fitness. On the other hand, we can imagine a complete absence of selection, where only transformations can change the composition of the population. In general, we would not expect the composition of types that the population might attain at any equilibria to be the same in the two situations. In real populations, there will be a combination of selection, transformation and drift impacting on the composition of types. This thesis concerns the interaction of selection and transformation.
Adaptation is the phenomenon most usually considered as the main effect of selection.
Transformation has no single effect. The discussion of micro-evolutionary models thus far has referred only to genotypes as the types involved in evolution. But from the way I have characterized the general micro-evolutionary model, any domain of information about an organism satisfying two criteria will be involved in evolution and should be considered a part of an individual's type. This information must be determined by the organism's parents, and must either affect the organism's fitness or help determine the types of its offspring. But only some of this information is both determined by its parents and will be transmitted to the offspring or affect its fitness.