neutral network

Masel J & Trotter MV 2010 Robustness and evolvability. Trends Genet 26:406-414.

• robustness to mutation allows genetic variation to accumulate in a cryptic state

• hybridization between two dissimilar lineages can be thought of as a major one-off perturbation in genetic background that triggers the revelation of cryptic genetic variation
• this often manifests as 'transgressive segregation'

• some authors have argued that it is impossible for natural selection to favor evolvability [93,94]
• these general arguments have been comprehensively rebutted elsewhere [95], leaving the possible extent and nature of the evolution of evolvability an open question