Intelligent Design and the Limits Question

The central design question is not simply whether evolution occurs. Mutation occurs. Natural selection occurs. Genes duplicate. Protein functions change. Gene regulation changes. New genes can arise. Populations diverge and speciation occurs.

The question is how far these processes take us. An Intelligent Design investigation asks whether known mechanisms, together with the available historical evidence, adequately account for the origin of particular structures, functions, developmental systems, and forms of biological organization.

This question must be asked case by case. A limitation demonstrated for one mechanism does not establish a universal limit on evolution, while a successful evolutionary explanation for one innovation does not establish that every innovation arose in the same way.

The evidence examined in this investigation demonstrates substantial evolutionary change. It includes experimentally observed adaptation, new metabolic capability, gene duplication and functional divergence, evidence concerning de novo gene birth, changes in protein function and regulation, speciation, developmental modification, and convergence.

At the same time, research into evolutionary novelty recognizes distinctions among the origin of new attributes, new functions, larger anatomical transformations, diversification, and ecological success.

Design is not established merely by identifying something that has not yet been explained. Scientific understanding changes, and mechanisms that once were unknown may later be discovered. A design argument therefore needs positive reasons for considering purposeful organization rather than depending only upon a present gap in knowledge.

What observations would distinguish an actual limit of undirected evolutionary mechanisms from a temporary gap in present knowledge? What positive evidence would allow purposeful organization to be evaluated as an explanation rather than simply invoked where an evolutionary history is incomplete?