The concept of design thus is central to both creation science and ID. Although ID claims to be agnostic on much of creation science, such as the age of the Earth, Noah’s Flood, and the like, when it comes to design, creation science and ID speak in one language. This language is that of William Paley, whose argument from design in his 1802 Natural Theology proclaimed that structural complexity of biological organisms was evidence for the existence of God (Paley, 1802).

Like the irreducible complexity argument, the other prominent claims made by the ID movement, and often the specific terminology, trace back to creation science. “Specified complexity” entered the antievolution literature in Thaxton et al. (1984), in the midst of a chapter that attempted to repair the infamous creation science shibboleth, much ridiculed by scientists, that a decrease in entropy in biological systems contradicts the Second Law of Thermodynamics. The authors grudgingly conceded that local decreases in entropy were not prohibited in open systems like the earth, which experience a continuous energy flow, but claimed that genetic information exhibits specified complexity, and that thermodynamic limitations block any nonintelligent increase in information. More generic “no new information” arguments had been made by the European creation scientist A. E. Wilder-Smith, who has been repeatedly cited as an inspiration by many ID proponents (Touchstone, 2004). Other ID arguments, such as the claim that there are no transitional fossils in the fossil record or that “microevolution” is proven but “macroevolution” is dubious, are indistinguishable from those in the creation science literature (Matzke and Gross, 2006).

The microevolution/macroevolution distinction is particularly revealing. In evolutionary biology, microevolution refers to evolutionary processes operating within a species. Although scientists sometimes colloquially refer to macroevolution as “evolution above the species level,” this definition does not do justice to the complexity of topics included within the concept. Macroevolution refers to patterns that emerge as species and lineages branch through time, including the rate and pace of evolutionary change, adaptive radiation, morphological trends in lineages, extinction or branching of a lineage, concepts such as species sorting, and the emergence of major new morphological features (such as segmentation, or shells, or the fusion or loss of bones). Decades ago, creationists began to use microevolution and macroevolution idiosyncratically. Creationists’ use of “microevolution” is not dissimilar to that of evolutionary biologists, although they apply it not just to species but to evolution within the limits of a specially created “kind” of organism. When ID supporters and other creationists claim to accept some evolution, they generally mean it in this limited sense of evolution “within the kind.” A larger distinction occurs in the creationist definition of macroevolution, which to them