By time of the Origin, however, Darwin favored gradualism. Existing species separated by discrete gaps in characteristics.
Intermediates often have little or no selective value.
Too distinct to have evolved gradually. Gingerich's summary of evolutionary rates. The crucial difference between punctuated equilibrium and phyletic gradualism concerns the rate of evolution at, and between, splitting events. Problem not yet entirely resolved. Saltational change seems to occur in some lineages, gradual change in others.