Ayala, Francisco J. “Darwin’s Devolution: Design Without Designer.”

According to Francisco Ayala, Darwin’s achievement was to complete the Copernican revolution; biology could now be explained in terms of universal, immanent, natural laws without resorting explicitly to a Creator. The result was to bring biological organisms into the realm of science. Many theologians have seen no contradiction between Darwin and Christian faith, both at the time of Darwin’s writings and in the century since. Natural selection is creative: in a “sieve- like” way it retains rare but useful genes. But natural selection is not creative in the Christian sense of creatio ex nihilo. Instead it is like a painter mixing pigments on a canvas. It is a non- random process that promotes adaptation, that is, combinations useful to the organisms. By proceeding “stepwise,” it produces combinations of genes that otherwise would be highly improbable. It lacks foresight or a preconceived plan, being the consequence of differential reproduction. Thus, though it has the appearance of purposefulness, it does not anticipate the environment of the future. It accounts for the “design” of organisms, since adaptive variations increase relative survival and reproduction. Aquinas and Paley understood that purely random processes will not account for biological nature; but they could not recognize, as Darwin saw, that these processes could be “oriented” by the functional design they convey to organisms. In this sense they are not entirely random. Chance is an integral part of evolution, but its random character is counteracted by natural selection which preserves what is useful and eliminates the harmful. Without mutation, evolution could not happen. Without natural selection, mutations would bring disorganization and extinction. Thanks to Darwin we can view the process of evolution as creative though not conscious. The biological world is the result of natural processes governed by natural laws, and this vision has forever changed how we perceive ourselves and our place in the universe.

Ayala next develops a complex conception of teleology. An object or behavior is teleological when it gives evidence of design or appears to be directed toward certain ends. Features of organisms, such as the wings of a bird, are teleological when they are adaptations which originate by natural selection and when they function to increase the reproductive success of their carriers. Inanimate objects and processes, such as a salt molecule or a mountain, are not teleological since they are not directed towards specific ends. Teleological explanations, in turn, account for the existence of teleological features. Ayala then distinguishes between those actions or objects which are purposeful and those which are not. The former exhibit artificial or external teleology. Those resulting from actions which are not purposeful exhibit natural or internal teleology. Bounded natural teleology, in turn, describes an end-state reached in spite of environmental fluctuations, whereas unbounded teleology refers to an end-state that is not specifically predetermined, but results from one of several available alternatives. The adaptations of organisms are teleological in this indeterminate sense. Finally, teleological explanations are fully compatible with efficient causal explanations, and in some cases both are required.

With this in mind Ayala argues that Darwin’s theory of evolution and his explanation of design are no more “anti-Christian” than are Newton’s laws of motion. Divine action should not be sought in terms of gaps in the scientific account of nature - although the origin of the universe will always remain outside the bounds of scientific explanation.

The essay concludes by acknowledging the success of science as a way of knowing, a major source of economic growth in the United States, a bringer of essential technologies, and a mode of accumulating knowledge that spans generations. Still, science is not the only way of knowing; we also have the arts, common sense, religion, and so on, all of which far predate science. Science is universal in scope but hopelessly incomplete. Much of what is left out, such as meaning and value, may be considered more important than what science includes.

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