He points out that artificial selection by animal breeders produces great diversity but no new species. The beaks of finches on the isolated Galapagos islands changed when climate conditions changed, but no new species appeared. Artificial selection of fruitflies does produce forms that do not breed with their ancestors, but it is not clear that they should count as a new species.[viii].
Johnson notes that the creatures found in the early Cambrian period (about 570 million years ago) were very different from those found in Precambrian strata. As many as 100 new phyla (groups of similar species with a common body plan) appeared in a relatively short interval, though only 30 of these remain today. Thereafter few new phyla appeared -- even when mass extinctions (such as those caused by the impact of comets) opened up new ecological niches; instead, extensive diversification occurred in existing phyla. Moreover, many species changed little over periods of millions of years; paleontologists had often ignored such stasis because they were looking for change. Johnson accepts Gould's concept of punctuated equilibrium, though unlike Gould he thinks that the Cambrian explosion was a product of God's intervention and not of natural causes.
Johnson also argues that random mutations could not have produced the coordinated functioning of many parts that occurs in complex organisms. An effective eye, for example, requires not only the coordination of diverse parts but also the presence of neural and cerebral structures. He replies to Dawkins' speculation that webs on the limbs of small tree-climbing animals would have enabled them to glide, leading eventually to wings for flying. Johnson says that such webs would have hindered climbing and food grasping long before they could have supported flight. He says that Darwinists have elevated chance into an ultimate principle that is inherently anti-theistic.
