Developmental Instability and Evolution in Peripheral Isolates

It is proposed that inbreeding, directional selection, and drift in small peripheral isolates could alter the genetic milieu to the point where the developmental feedback and regulatory devices would be disrupted. The consequence of such may be sporadic penetrance of expressions hidden by developmental canalization. These variants add to the phenotypic repertoire of an isolate, and may be incorporated and then fixed. Should an isolate succeed in establishing a new adaptive mode and barriers to gene exchange, it may give rise to a discrete population system with expressions which depart radically from those of the parental species.