’Many evolutionary biologists since Darwin’s time have been struck by the failure of the fossil record to conform to the gradualist model. Few sequences have ever been found that represent gradual transitions of species. Instead, fossil species usually appear suddenly in a layer of rocks, and may persist essentially unchanged for the whole time they exist on earth, finally disappearing from the record of the rocks as suddenly as they appeared.’
Campbell Mitchell and Reese, Biology Concepts and Connections, Benjamin Cummings 1994, p286

Evidence News 2 February 2012