1. Purifying / stabilizing selection is not the sole cause of stasis. 2. The reason can be that methods for detecting stabilizing selection are complex. 3. Inheritance alone is too imperfect to achieve a purifying and stabilizing selection. 4. Stabilizing selection is the opposite of disruptive selection. 5. For example, long-term stabilizing selection related to stable environments might cause stasis. 6. Graph 2 depicts stabilizing selection, where the intermediate phenotype is favored over the extreme traits. 7. Likewise, pleiotropic gene's stabilizing selection allows for the allele frequency to be altered. 8. Stabilizing selection favors the middle phenotype, causing the decline in variation in a population over time. 9. The stability is explained by the purifying / stabilizing selection of body plans and the constructional restictions. 10. His work in evolutionary biology includes a theory for the origination of the " locked in " by stabilizing selection.