An Engineering View of Darwinian Evolution

Dan Waddill
PhD, Environmental Engineering


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, literature, 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, game plans, flight plans, lesson plans; battle plans, electrical plans.  We dream, we intend, we design, we plan.  At times, 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 the 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 understand how penicillin fit the plan, what purpose it filled, 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 and bridge and road, every bicycle, every bookcase, every bathtub and table and television; every cell phone and computer, every city, every machine, every shoe and scalpel, pot roast and telescope; every textbook, every poem, every song and sculpture, sketch and photograph – all arose by purposeful design.  The well-known Story of Objects – all human-made objects, each and every one – is a documentary of countless coordinated steps, intentionally planned, purposefully designed, and continuously directed toward a specified goal. 

In contrast, the veiled and mysterious Story of Life – set against the vast expanse of earth and sea and sky, across every moment in time, and casting every plant and animal and microbe that ever grew – has been edited to exclude all notions of planning, purpose, and design.  The Story of Life has become the tale of Darwinian evolution, which the 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 puts 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 origin of objects.  Whereas human-made objects arise through foresight and design; living species (and all of their parts) are said to arrive unplanned, evolving blindly through a maze of random variation and struggle for life. 

While the Story of Objects occurs in the present, the Story of Life is set in the distant past, when no one was there to see it or record what happened.  Nor can we observe it now, because the evolution of life is slow, and nothing much changes during one human lifetime or even hundreds of lifetimes.  We may observe beaks growing larger or wings getting darker, but finches and moths do not appear from scratch, because such advancements, we are told, arrive more slowly than the millennia.  With the action of gravity or morphine or electrons, we can watch the whole show, again and again, from beginning to end, and science thrives on such regular, repeatable phenomena.  But the advancement of life occurred only once in earth’s history, and humans arrived late; so we see only the last few scenes, plus an assortment of snapshots: the boney fossils, amber inclusions, and scattered remnants of ancient forms.  The Story of Life is rich in history but poor in evidence, offering limited data to fuel the scientific process. 

Thus, while it may be possible to imagine that life arose unplanned, such a view is certainly not required, especially when the present world – the world we know – doesn’t work that way.  In the world we know, nothing is built unplanned.  In the present world, advancements always follow foresight, intent, and design.  Bridges are conceived to fit a purpose, and bridges stand because they are designed to carry the load.  The failure of a bridge indicates poor design, not lack of design.  Robots are created not in countless disconnected steps, but in thousands of coordinated actions; not blindly, but with foresight, following a vision toward a distant function.  In the world we know, aimless steps don’t just stumble onto a purpose; the purpose comes first, and the vision guides countless steps toward the intended function. 

Granted, living things differ from human-made objects.  Life reproduces on its own, whereas objects clearly do not – bridges and robots are designed and built by others.  Unlike life, human-made objects have no offspring; machines do not reproduce.  But is life, therefore, so different?  A living thing may be more than mere machine, but it remains machine in part, and the mechanical parts require engineering explanations.  The heart of a poet may be true or false, lonely or battered, light or heavy or lost, but the heart of an engineer is a pump, a machine for moving blood.  Whether they cross for luck, lift to help, or point to accuse; our fingers are mechanical levers driven by muscles and tendons, as the bucket of an excavator is driven by hydraulics and pistons.  Nerves transmit electricity throughout the body, as power lines carry it across the country.  Despite their differences, organisms and objects inhabit the same real world; they are subject to the same laws of nature; and each must be built to work.  Clocks and antelopes have to run; jets and sparrows need to fly.  At the end of the day, the Story of Life must account for all of the mechanical, electrical, and structural features of living things. 

Granted too, living things have been in existence much longer than human-made objects.  Objects may be built in a day or a month or a year, whereas life on earth evolved over billions of years.  Darwin saw no limit to the changes that may accumulate during “…the long course of time by nature’s power of selection.”  As cosmologist Carl Sagan puts it, “The secrets of evolution are time and death. Time for the slow accumulations of favorable mutations, and death to make room for new species.”  In Climbing Mount Improbable, biologist Richard Dawkins aptly compares Darwinian evolution to hiking in the mountains, as organisms evolve by “crawling up the gentle slopes, inch by million-year inch.”  In Darwinian evolution, every misstep ends in death, but the lucky survivors – those who stay on the unseen path – move up the gentle slopes, slowly, gradually, one step at a time, generation after generation.  Given enough time, the select few may come upon a favorable summit and acquire some new feature, such as a wing or eye or elbow or enzyme.  In Dawkins’ analogy, the gentle slopes always rise to the occasion, but reality may not be so accommodating.  If the evolutionary pathway to a working wing encounters sheer cliffs or impassable ravines (to extend the analogy), then Darwin’s slow crawl grinds to a dead stop, and the summit (the wing) remains forever unknown and out of reach.  Without the gentle slope, the Darwinian process doesn’t work, and time makes no difference: a billion years or 10 billion or 100 billion are not enough.  In the Story of Life, time is a supporting actor but not the hero; time does not come to Darwin’s rescue. 

In weighing the Story of Life against the Story of Objects, the issue is not “evolution” per se, as evolutionary change is everywhere the rule, not the exception.  With living things, evolution is hidden in the unseen past; but fossils, comparative anatomy, and biochemistry suggest that life has indeed evolved.  With human-made objects, the changes unfold before our eyes.  We note the evolution of computers and cars and cell phones, shoes and chairs, faucets and football pads.  Screens get flatter, engines stronger, batteries smaller, helmets lighter.  Pushbuttons give way to touch screens; laces to Velcro, straight backs to recliners.  Razor blades once acted alone, but now they conspire in gangs of two or three or five.  From the edge of extinction, vinyl records and turntables have made their comeback.  Luggage has sprouted wheels.  One way or another, evolutionary change is made to fall on human-made objects and living species alike. 

Nor is the issue common ancestry.  If bones suggest an unseen common ancestor for whale and bird and lion, then wheels point to an unknown predecessor of the cart, the bicycle, and the locomotive.  Cobbled streets, asphalt roads, and concrete highways share a mutual ancestor in the dirt path.  If we imagine the horse evolving from dog-sized Eohippus to full-sized Kentucky Derby winner, then we may also recall the evolution of the rocket from Chinese fire arrow to German V-2, American Saturn V, and SpaceX Falcon.  Objects, like living things, may evolve from common ancestors. 

Nor is the issue the loss of function.  With human-made objects, loss of function may arrive unplanned, purely by accident and without intention or design:  computers lock up, cars break down, tires go flat.  Screens crack, toasters fry, pumps fail.  Drains clog as pipes leak.  The internet drops.  “Why,” we wonder, “isn’t this working?”  Likewise, living things endure the steady betrayal of unplanned and accidental losses, as birth defects, genetic disorders, and deadly mutations appear in the offspring, rarely but steadily and without intention or design.  Clearly, unplanned processes have the capacity to damage or destroy existing things; that’s just how the world works, and it happens to organisms and objects alike.  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, or springs into struts.  Likewise, a single mutation may destroy vision or flight or any other living function, but it doesn’t follow that a billion unplanned 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.  Loss of existing function and creation of new function are as different as an abandoned road and a bustling factory, as separate as chaos and cosmos.

Nor is the issue a legal matter.  The engineer is interested in scientific data, not legal opinion.  From the engineering perspective, the legal battles over evolution simply interfere with the normal scientific process and obstruct the free competition of ideas, as federal judges strike down all criticism of Darwinian evolution.  Censored from public education are scientifically true statements, such as Darwin's theory “… is still being tested as new evidence is discovered,” and “gaps in the theory exist for which there is no evidence.”  Banned from science textbooks are stickers saying the theory of evolution “…should be approached with an open mind, studied carefully, and critically considered.”  Outlawed from the classroom is any mention of Intelligent Design.  Thus Darwin’s theory – a tale of struggle for life and survival of the fittest – is sheltered from competition and granted life without struggle, its survival ensured regardless of fitness.  Irony aside, the situation is uniquely unscientific:  chemistry has no Dover Decision, physics no Monkey Trial.  The Big Bang theory prevails in physics because it offers the best explanation of the data, not because a judge ruled in its favor.  Science needs no legal protection. 

Nor is the issue “science versus religion.”  The engineering view cares not one rivet about the religious implications of Darwin’s theory, or any other theory for that matter.  The engineer asks only one question of Darwinian evolution: “does it work?”  In other words, can the Darwinian process actually build, as claimed, every feature of every living thing?  The answer to this question depends on real world observation and logical analysis, not wishful thinking or dogmatic belief in God’s absence or presence.  Granted, the religious and cultural implications of Darwin’s theory are profound, but such concerns do not alter the engineering calculations or modify the scientific evidence. From the engineering perspective, the backdrop of atheism versus theism is simply irrelevant, regardless of how stunning that landscape may appear from other vantage points. 
From the engineering perspective, the fundamental issue of evolution – the heart of the matter – is the emergence of new function and novel features.  Specifically, the engineer wants to know what mechanism has driven the advancements, the innovations, and the major upgrades in living organisms over time.  Within our classrooms and courtrooms, Darwin is selected as the fittest, but can he survive outside those protected chambers, in the real world of engineering?  For a moment, let us ignore the clutter of preconceived notions, wrinkled assumptions, and moldy arguments.  No more hand waving; no more ridicule.  Let us pin evolution to the drafting table and see what sort of picture emerges under the objective rules of engineering and science, where bias must be checked at the door, and the outcome depends upon observation, testing, and logical argument.

In his 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 re-named “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, everything new – every new structure, every new function – arrives by these small unplanned steps, the mutations of heredity, the drift and flow of procreation.  In contrast, natural selection proposes nothing and originates nothing; instead, it simply responds, sifting the changes, destroying the weak, and preserving the profits by killing the poor. 

Thus, the Darwinian process is blind and unplanned, with no purpose or goal beyond an individual’s urge to reproduce and deliver one more generation.  It does not yearn or reach; it has no intelligence and no awareness.  Darwinian evolution cannot look ahead to design a complex function such as flight or vision or photosynthesis; instead, it operates only in the present, step by aimless step, with each step being a random mutation (or other unplanned variation) that causes the offspring to inherit a change in shape or function. In the subsequent struggle for life, the indifferent hand of natural selection eliminates the steps that can’t compete, allowing the profitable steps to survive and reproduce in greater numbers.  With no memory of the past and no vision for the future, the profitable steps accumulate one by one, over millions of years, eventually stumbling onto new structures such as wings and eyes, new biochemical pathways such as photosynthesis, and new forms of life such as birds and mammals.  So the story goes.

Without question, life is subject to the Darwinian process of random mutation and natural selection.  It’s just the way of the world.  Mutations do occur, and natural selection acts continuously and automatically upon the offspring, resulting in noticeable developments:  bacteria with antibiotic resistance, moths with darker wings, finches with larger beaks.  Clearly, the Darwinian process has the ability to produce small changes in existing organisms, but such fine-tuning is not the issue at hand; instead, we want to know if unplanned evolution can build an entire microbe or moth or bird from scratch. 

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 5000 mutations to accumulate into a viable wing; it acts on each mutation at every step.  Thus, Darwinian evolution faces a fundamental 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 therefore yields no profits, no reproductive advantage.  In Darwin’s time, the English biologist Saint 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:  some alternate advantage (not flight) 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.  With the next step – the next mutation – the scurrier takes to the air. 

So the story goes.  But the whole of 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 – matters of faith, not science.  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% of a wing, you can’t fly with 5 or 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 we know, the world of nature – Darwin’s theory hits a limit; it encounters a boundary that no unplanned process can cross. 

It gets worse.  Since Darwin’s time, science has discovered the microscopic universe that underlays the visible features of life.  As a result, the Story of Life must explain not only the creation of wings, but also the emergence of structural proteins that comprise each feather, the advent of molecular filaments and bridges and pumps that move muscles in flight, the chemical cascade that drives the flow of energy, and the enzymes that lubricate each reaction.  In the past 160 years, science has discovered the exact inner workings of these and countless other biochemical systems, such that the professional journals are overflowing with precise drawings and detailed descriptions, right down to the specific role of each atom in every molecule.  Life is built upon the internal biochemical systems that create vision, construct bones, digest food, absorb light, capture sound, clot blood, transmit energy, remove waste, and perform a thousand other functions.  We know exactly how these systems work, but where do they come from? 

Evolutionary biology rejects the possibility of planning or design, and instead gives full credit to unplanned evolution – Darwinian evolution – with its slight, blind, and profitable steps.  If true, the engineer expects to see the steps and count the profits.  In other words, for any given biochemical system – say photosynthesis – evolutionary biology should be able to demonstrate a sequence of molecules that starts with something simple, changes by slight steps (random mutations), and ends with the complex molecules of photosynthesis.  Moreover, since Darwinian evolution requires every step to have a profitable function (something that favors survival and reproduction), evolutionary biology should be able to describe the precise function of each step along the way.  We know photosynthesis occurred with the last step, but all prior steps must have done something too – not photosynthesis (it would come later) but something else:  something useful, something profitable, something that conveyed a reproductive advantage.  What, precisely, did the prior steps do?  For that matter, how many prior steps were there?  Given the complexity of photosynthesis, there must have been hundreds or thousands of prior steps, each with a useful function, an adaptive advantage.  What were they? 

The answers are not forthcoming.  In 1996, biochemist Michael Behe noted, “If you search the scientific literature on evolution, and if you focus your search on the question of how molecular machines – the basis of life – developed, you find an eerie and complete silence.”  Behe was met with outrage and ridicule, but the uproar did not alter the facts.  In 2001, biochemist Franklin Harold noted, “…we must concede that there are presently no detailed Darwinian accounts of the evolution of any biochemical system, only a variety of wishful speculations.”  Since then, evolutionary biology has struggled to propose the odd intermediate step (the type III secretion system, for example), but the Darwinian process requires not just one or two intermediate steps but an unbroken trail of countless steps, so the isolated exceptions merely prove the rule:  biochemical systems lie beyond the creative reach of Darwinian evolution.  From the Darwinian perspective, biochemical systems are remote and isolated, like islands in a chain, or planets in their systems.  Darwin’s blind, step-wise process cannot crawl from one biochemical function to another any sooner than an explorer might march from Oahu to Maui, or an astronaut stroll from Mars to Jupiter. 

To the engineer, this result comes as no surprise.  Biochemical systems may be microscopically small, but they are, nevertheless, real devices – mechanical motors, chemical reactors, electrical circuits, communications networks, transportation systems, environmental sensors, and informational databases – different in size but not in essence from their larger engineered counterparts.  In the world of engineering, the development of a working system – a motor, for example – involves countless steps along a pathway meticulously planned, with few traces of intermediate advantages or alternate functions along the way.  The motor’s the thing, and the working motor arrives only with the final step.  Of the hundreds or thousands of prior steps, any may serve to prop a door or hold down paper, but these functions are dead ends – they convey no meaningful advantage on the pathway to a working motor.  This reality applies to automobiles and bacteria alike, as molecular experiments show that the biochemical motor in the bacterial tail (the flagellum) doesn’t spin unless all of its parts are in working order.

Thus, engineering experience and nature’s evidence converge upon two conclusions:  1) biochemical systems cannot function – they convey no advantage – until their various parts are produced and assembled, and 2) alternate functions may exist in isolation, but they do not form a continuous sequence of useful steps that leads to the final working system.  When evolutionary steps aren’t useful – if they convey no adaptive advantage – then the blind eye of natural selection views all offspring as equal, and it kills them in equal proportion, altering nothing, and playing no part in the evolutionary process.  Without natural selection, the Darwinian process is reduced to random mutation alone – pure chance – with no more likelihood of building higher life forms than “…the chance that a tornado sweeping through a junk-yard might assemble a Boeing 747 (astronomer Fred Hoyle).”

Evolutionary biology may imagine otherwise, but scientific observation and the evidence of nature reveal the inability of Darwinian evolution (with its family of unplanned and unintended processes) 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 biochemical systems such as photosynthesis; new structures such as wings and eyes and leaves; and new forms of life such as birds and trees and bacteria.  Without doubt, unplanned evolution contributes to the Story of Life, but it serves more as editor than author, nudging the plot, polishing a scene, eliminating a character.  The full story must be written by planned evolution – engineered evolution, progressive creation – which has the vocabulary to construct new function and novel features through foresight, purpose, and design. 
In the real world, mechanisms for planned evolution are common, effective, and well known to science.  Planned evolution occurs with the selective breeding of plants and animals, as a breeder envisions a goal – say bright flowers or milk production or floppy ears – and chooses to propagate only those seeds or calves or puppies that come closest to the goal.  Another type of planned evolution occurs with genetic engineering, as geneticists arrange fragments of DNA to create new living function, the way an author arranges characters on a page to create a poem, or an engineer arranges systems of equations to design a bridge.  Without question, life evolves under the planning of human design, purpose, and intent.  But humans are late arrivals on the earth, so the idea of planned evolution raises an obvious question: during the eons of pre-human history, who was the planner?  We’d like to know the identity of the primordial designer, the one who had the vision and drew up the plans.  Simply put, who did it? 

Granted, we’re curious, but “who did it?” and “how did it occur?” are separate questions, and science may be able to answer one but not the other.  Archaeologists, for example, separate fragments of pottery from bits of earth without knowing the identity of the potter.  Medical examiners distinguish accidental death from intentional murder with no thought of naming the killer; instead, they apply the tools of forensic science to determine cause of death, whoever or whatever it may be.  If the evidence points to homicide, it would be a corruption of truth and justice for a medical examiner to certify an accidental cause of death in order to deflect suspicion from a powerful politician, a wealthy patron, or a close friend.  Likewise, evolutionary biology must set the implications aside and simply face the evidence.  In the Story of Life, the evidence points to an author – a designer, a planner – whether we know who did it or not, whether we admire the suspects or hold them in contempt.  Atheism may wish to unseat the creator, and theism may wish to find God in evolution, but science responds to evidence, not wishes.  Engineering looks for processes that actually work, not imaginative stories.
In order to present a full account, the Story of Life must be a dialogue of planned and unplanned processes, both engineered and Darwinian.  Since Darwin’s time, evolutionary biology has turned a deaf ear to the planned role, but the evidence continues to speak, with increasing clarity and volume, as science reveals the myriad features of life that lie beyond the reach of Darwin’s blind process.  Regardless of anyone’s wishes, planned evolution is necessary to explain the arrival of wings and eyes and enzymes and a thousand other innovative forms and functions.  Added to the unplanned processes of Darwinian evolution, planned evolution moves the Story of Life from fiction to non-fiction, from myth to reality, from folktale to documentary.  Planned evolution allows the Story of Life to match the real world, to be a true story.  Whether we like it or not – whether we know who did it or not – planning and purpose are fundamental to the evolution 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. 

Such is the view from engineering.