One of the major questions concerning the interplay between phenotypic plasticity and the evolution of organisms
is whether genetic fixation of plastic traits is a mechanism
commonly used to couple environmental input with genetic
information. Sommer and Ogawa (2011), argue that a number
of requirements must be fulfilled for a successful case study.
First, detailed knowledge of the developmental process under
study, especially at the genetic level, should be available, such
that variation in molecular mechanisms controlling a particular trait can be investigated. Second, phenotypic variation
among populations, or variability between closely related
species, for the trait under investigation should exist. Third,
knowledge of the phylogenetic framework of the individuals
or populations investigated must be robust enough to support
the directionality of evolutionary change.