Flights of Imagination

An Engineer Examines Darwinian Explanations

In the world of engineering, plans are fundamental, purpose is the rule, and design is everything. The same may be said of art, business, medicine, sports, and any other human endeavor. We humans reach our destinations not by chance but by design, following the plans we make—floor plans, financial plans, health plans, lesson plans, and game plans.

Our designs may stumble or stray, and occasionally we bump into a discovery by accident—penicillin, for example—but even then, someone must recognize that the accident fits a purpose, or the unintended step goes nowhere. Penicillin may have arrived unexpectedly in a moldy petri dish, but Dr. Fleming had to notice it, and the medical community had to recognize how penicillin fit a plan, what purpose it fulfilled, and what goal it achieved.

Thus, it is safe to say that every human-made object owes its existence to purpose and design—every car and jet, cell phone and computer, song and ­sculpture. Their stories are written in countless coordinated steps, intentionally planned, purposefully designed, and continuously directed toward a specified goal.

In contrast, the veiled and mysterious story of life has been edited to exclude all notions of planning, purpose, and design. It has become the tale of Darwinian evolution, which biologist Richard Dawkins describes as a “blind, unconscious, automatic process” with “no mind and no mind’s eye. It does not plan for the future. It has no vision, no foresight, no sight at all.” As Charles Darwin put it, “There seems to be no more design in the variability of organic beings, and in the action of natural selection, than in the course which the wind blows.”

Thus, the accepted version of the origin of species sits in sharp contrast to the well-known pattern of the origin of objects. Whereas human-made objects arise through foresight and design, living species (and all of their parts) are said to have arrived unplanned, having evolved blindly through a maze of random variation and struggle for life.

In weighing the origin of species against the origin of objects, the issue is not “evolution” per se, if we define evolution as mere change over time. Indeed, designed objects are known to “evolve” through time. Screens get flatter, engines stronger, batteries smaller. Pushbuttons give way to touch screens, laces to Velcro, straight backs to recliners. Luggage has sprouted wheels. One way or another, change falls upon human-made objects and living species alike.

Nor is the issue the loss of function. With human-made objects, loss of function may arrive without intention or design: computers lock up, cars break down, toasters fry. Likewise, living things endure the steady betrayal of unplanned and accidental losses, as birth defects, genetic disorders, and deadly mutations appear in the offspring. Clearly, unplanned processes have the capacity to damage or destroy existing things, and it happens to organisms and objects alike.

But creation is a different matter. While a single accident may destroy a car, a billion accidents will never fit a car with wings to make it fly or change carburetors into fuel injectors. Likewise, a single mutation may destroy vision or flight or any other living function, but it doesn’t follow that a billion uncoordinated mutations can create a working eye from sightless matter or wings from flightless appendages. If a string of accidents can’t make a flying car, surely we may wonder if a string of accidents can make a flying mouse.

From the engineering perspective, the fundamental issue of evolution is the emergence of novel features and new function. The engineer wants to know what mechanism has driven the innovations, advancements, and major upgrades in living organisms over time.

So let us pin evolution to the drafting table and see what sort of picture emerges.

The Inner Workings of Darwinian Evolution

In On the Origin of Species (1859), Charles Darwin argued for “one general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die.” Darwin called this struggle of life and death “natural selection,” a process Herbert Spencer famously renamed “survival of the fittest.” According to Darwin, natural selection “acts only by the preservation and accumulation of small inherited modifications, each profitable to the preserved being.” The key word is “profitable.” In the Darwinian struggle for life, the business is survival. Profits are earned through reproductive success, and all else counts as loss. If an inherited modification fails to increase the production of offspring, natural selection exerts no influence and the business falters.

 In Darwinian evolution, nothing changes by leaps or bounds; instead, one slight variation follows another, step by step, generation after generation. Modern science points to random mutation as the primary source of these small changes, with additional input from genetic drift, nonrandom mating, gene flow, and other unguided processes. In Darwinian evolution, every new structure and function arrives by small, unplanned steps in the drift and flow of procreation. Natural selection proposes nothing and originates nothing. It simply responds—sifting the changes, destroying the weak, and preserving the profits.

Without question, life is subject to the Darwinian process of mutation and natural selection. Mutations occur, and natural selection acts continuously upon the offspring, resulting in some noticeable developments: bacteria with antibiotic resistance, moths with darker wings, or finches with larger beaks. The Darwinian process has the ability to produce small changes in existing organisms, but such fine-tuning is not the issue. We want to know if unplanned evolution can build an entire microbe or moth or bird from scratch.

The Problem of New Construction

In order for the Darwinian process to build something new—say, a wing—each single step must outcompete the previous step. Natural selection acts relentlessly to eliminate the weak, and it won’t wait for 5 or 500 or 5,000 mutations to accumulate into a viable wing; it acts on each mutation at every step. Thus, Darwinian evolution faces a basic problem: it would take a continuous sequence of countless mutations to build a complex structure like a wing, but the individuals in the sequence would not have the advantage of flight until the wing was finished, or nearly so. Because natural selection only preserves profitable modifications, it can have no effect during the early stages when the wing is not yet functional, and it therefore yields no reproductive advantage.

Darwin’s contemporary, St.  George Jackson Mivart, described this problem as “the incompetency of ‘Natural Selection’ to account for the incipient stages of useful structures,” an objection put more simply in recent times by Harvard biologist Stephen Jay Gould, who noted, “you can’t fly with 2% of a wing.” The idea is that the direct Darwinian process cannot create any feature of life (such as a wing) that has no beneficial function and therefore conveys no reproductive advantage until its numerous parts are produced and assembled.

In such cases, Darwinian evolution would need to advance indirectly, with each mutation producing an alternate advantage, anything to pass the audit of natural selection. To illustrate, the construction of a wing would require countless evolutionary steps, but only the final step would produce a creature that can fly on functioning wings. All prior steps would generate non-flyers—scurriers, crawlers, leapers—randomly fitted with pre-wings that cannot support flight but must do something else that enhances survival and reproduction. Lacking foresight, the Darwinian process must wander blindly from one alternate advantage to the next, generation after generation, until by chance it arrives one step short of a working wing, one mutation away from flight.

Tales of Creation

So the story goes. But the whole of applied science and engineering groans at such a tale of creation, because these mysterious alternate advantages are not observed in the real world; they exist in the imagination only, belonging to things unseen. In the real world of predator and prey, flightless appendages would earn no profit for creatures who must outrun their neighbors. And if we choose to imagine alternate advantages, we must also acknowledge a host of related afflictions. Just as you can’t fly with 2  percent of a wing, you can’t fly with 10 or 15 percent of a wing, and you can’t run very well either. In the real world, a flightless wing would be harmful, and the harm would simply increase as the partial wing developed. Imagination knows no bounds, but in the real world—the world of nature—Darwin’s theory hits a limit; it encounters a boundary that no unplanned process can cross.

Thus, the evidence of nature reveals the inability of Darwinian evolution to solve the fundamental problem of evolution: the emergence of new function and novel features. While random mutation and natural selection may destroy or alter existing things, such unplanned processes lack the ability to create new things—new structures such as wings and eyes and leaves, and new forms of life such as birds and trees and bacteria.

Without doubt, unplanned Darwinian evolution contributes to the story of life, but it serves more as editor than as author, nudging the plot, polishing a scene, or eliminating a character. The full story must include the capacity to plan and the foresight to construct new function and novel features by purposeful design. Whether we like it or not—whether we know who did it or not—planning and purpose are fundamental to the development of life on earth, foresight and design are stamped upon the living blueprints, and all life—including every one of us—is here by intent.