Here are some quotes from Michael Denton's book, Evolution: A Theory in Crisis: In the first two quotes, Denton speaks of the typological view of nature, which is the view that there are certain kinds or classes of animals and one type of animal cannot evolve into another type of animal. The last quote is a response to the claim that the lungfish is an intermediate form between fish and amphibians. Denton is saying that although the lungfish has both fish and amphibian characteristics, its individual organs are not transitional between fish and amphibian. Its gills and intestinal spiral valve are not transitional between fish and amphibian. Its heart is not transitional between fish and amphibians.