Tuesday, February 17, 2015

Evolution vs. Intelligent Design: Do We Have a Winner?

Some scientists now say that life on earth may have begun a billion years earlier than they'd originally thought.  But the breakthrough finding still leaves evolutionary science empty handed in answering two key questions:  How did life start?  And why, despite the conditions for life on earth being so perfect, did it only happen once, and then never again?

You gotta love Charles Darwin.  Ever since he put forth a theory in the 19th century that all life on Earth is descended from a common ancestor—yes, he’s saying you are great-great-great-whatever-grandson or granddaughter to an amoeba or something like it—religion has had its figurative shorts in a bunch.  First, the outraged faithful tried to ban the teaching of evolution in schools.  The Scopes “Monkey” trial threw a major wrench into those efforts, but Darwin haters haven’t given up.  More recently, believers came up with a new tactic to fight back against the science of evolution:  “Intelligent Design.”  This is the idea that life is too complex to be explained by a process so undirected as evolution, and therefore must involve the work of an intelligence.  ID authors normally don’t name the Designer.  But if the Designer walks like a duck—well, you get the idea.  Given that many of the most prominent proponents of ID began life as creationists, you don’t have to look hard to see what they’re up to. 

Every now and then a controversy erupts when an institution of learning refuses to let the ID folks inject their beliefs where they don’t belong.  Ball State University is one of the latest of those battlegrounds.  Last summer it banned the teaching of Intelligent Design in science classes, after someone complained about a physics professor who argued that nature shows evidence of intelligent design.  Four state legislators rushed to his rescue, going to battle with the university president in the name of “academic freedom.”  But these politicians wear their motives on their sleeves.  One of them, according to news reports, has tried previously to pass legislation requiring the teaching of Creationism—the belief that God created the world more less as described in the Bible—in school.

So how about it?  Does evolution explain everything?

In a word, no.  Nor does it claim to.  But what evolution has done is to lay out many incontrovertible facts for us that shed light on how the life process works.  Among them is the fact that life evolves, changing form over time.  Another is that life has existed on Earth for billions of years, and most definitely was not created over the course of a six-day workweek just a few thousand years ago.  These are observed certainties, as absolutely and concretely factual as this morning’s sunrise, and equally as impossible to explain away.  Religious zealots who refuse to accept this put themselves into the same class as those stubbornly clinging to the notion that the Earth is flat, thereby zeroing themselves out of the conversation.  It’s impossible to have a rational discussion with someone who is not open to the actual facts. 

Despite its roots in creationism, and despite its goal of discrediting evolutionary theory, ID proponents typically do not claim out loud the world was created in a week.  That’s good, because there’s a lot to talk about—and therefore argue about—for anyone who is willing to embrace the reality of the facts uncovered so far.  There are still plenty of blanks to be filled in.  Not every aspect of the evolutionary process is fully understood.  Scientists are still very busy looking for new facts, exploring new avenues, and forming and testing new hypotheses.  That’s how the discipline of science—and there’s that word again, science—works.  The final word on the study of evolution has not been written.  Far from it.  It may never be.

One principle of evolution that sends the faithful through the roof is that the process has no purpose or plan.  The question, “Where are we going with all this, and why?” has no answer.  Nor does evolution address the question of how life, and the Universe itself, came about in the first place.  Evolutionary science is a set of observations in need of an explanation.

Intelligent Design is the opposite.  It’s an explanation in need of an observation.  Intelligent Design teaches that evolution can’t explain why we’re here.  It then concludes that God—or something that looks and sounds very much like God—must be responsible.  That conclusion sounds reasonable and obvious to many.  But it does not derive scientifically from a study of the available facts.  ID offers no hypotheses that can be tested.  Its key conclusion, that some kind of intelligence exists that is responsible for designing life, and by extension all of creation, requires a leap of faith to believe.  This makes ID a religion, not a science.  And there’s nothing wrong with that.  But religion does not have a place in any science class.  Such classes are, by definition, reserved for the study of science.  Religion is taught down the hall or a couple of buildings over, under the auspices of a different department. 

Yet evolutionary scientists should pay attention anyway to what ID advocates are saying.  ID’s answers may fall short scientifically, but the questions it asks are perfectly valid.  That is why this passionate argument will not go away. 

Many processes are involved in the morphing of simple species into complex ones, and the divergence of existing species into new ones.  At the heart of the process is genetic mutation—the general idea being that random changes occur every so often in individual genetic material, the code that defines the organism.  “Good” mutations (bad ones are lethal) give rise to beneficial new characteristics and behaviors that favor survival and reproduction of the organism.  This leads to offspring better suited to thrive, who then pass the mutation down, and there you go—natural selection, or “survival of the fittest” as it’s sometimes called.  But this theory requires us to believe that life, in all its glorious complexity, essentially is the product of a series of random events.  According to current evolutionary theory, ultimately we’re all just a collection of organic chemicals that somehow, over the eons, got lucky, and managed to organize, crawl out of the ooze, and eventually become self aware, if somewhat confused. 

It is even theoretically possible for random chance to pull off such a seemingly miraculous accomplishment?

There’s an old saying in the study of chance and probability that if you were to put an infinite number of monkeys in an infinitely large room and have them bang away on an infinite set of keyboards for an infinite amount of time, they’d produce every book that’s ever been written or ever will be written.  This may be true from a mathematical sense, but it’s misleading bunk anyway.  First, you’d have to have an infinity of time to work with.  And even then, the resulting random productions of something that look intelligible would be completely lost in the noise, so buried in an infinitely huge mound of gibberish as to be undetectable and unusable.  Life on earth is not noise.  Nor has an infinite amount of time transpired between the beginning of life and the present day in which to produce the biological masterpieces we see before us.  In geological terms, 3.8 billion years is not exactly a blink of an eye, but nor is it anywhere near an infinity of time.  Plants and animals populating the earth today are incredibly complex, to the point where not every aspect of how they function is understood even now.  If these organisms were machines, we’d call them the products of amazing, jaw-dropping, breathtaking genius.  In a sense, they are machines—biological ones.  ID adherents have a point when they scoff at the notion that such seemingly ingenious complexity could possibly be the product of random chance.

As just one example, take the human visual system, beginning with the eye.  Here we have a small round sphere of opaque tissue, into which a hole covered by transparent tissue has been placed to allow the introduction of light.  There is a muscular mechanism to bend this lens in such a way as to focus the light into an image.  The interior of the sphere is filled with transparent liquid, to allow the light to pass through and strike a wall of tissue at the rear, where the image then forms.  This receiving tissue contains receptors that translate the light data into nerve impulses.  A nerve transmits these impulses to the visual cortex in the human brain, which is then able to reinterpret this data into an image.  Any one of the features and sub-systems described above would be amazing enough by itself.  The assembled mechanism is fantastically astonishing beyond words.  The eye even comes in nifty designer colors.  All this is the product of random chance?  It beggars the imagination.

Still, let’s not be hasty.  Why don’t we try a little experiment and see if we can determine how long it would take to construct a given genetic pattern by random chance alone.

Not to get too technical—but the human genome is made up of a linear sequence of codes in the form of specific organic compound base pairs, each of which can have one of four values.  Genomes are passed down to the next generation only through sex cells.  So for a mutation to occur and survive, it has to happen within a sex cell prior to or during reproduction. 

Let’s take a hypothetical species with a genome measuring 100 base pairs long.  In other words, our organism is defined by a 100-character word, written in a language containing only four letters.  For the purpose of our experiment, we’re looking for a specific word that will encode the precise qualities and capabilities we’re looking for.  And let’s be generous and say that our test species reproduces once an hour, and has current stable population of five billion, with births just keeping pace with deaths.  Now, let’s start with the first letter of our word.  To achieve a 100% probability of getting the correct choice by random chance, we’d have to roll our die (in this case, a specially-designed one containing just four letter choices) four times.  Now let’s move on to the next position.  To be sure of getting that one right also requires four rolls of the die.  But to reach a 100% probability of getting it right at the same time the one next to it is correct requires us to roll two dice, and to toss them 4 x 4 times—4 to the second power, sixteen rolls in all.  To be sure of getting the entire sequence exactly as you want it by random chance would require us to roll a hundred dice in each throw, one for each character position, and do it 4100 times—which works out to 1.6 novemdecillion rolls.  A novemdecillion is a 1 followed by 60 zeros. 

And remember, we’re allowing ourselves 5 billion throws an hour.  That may seem like a lot, but to go through every combination at that rate in order to hit that 100% probability of success, we’d have work at it for 36 quattuordecillion years.  A quattuordecillion is 1045—a one with 45 zeroes. 

Of course, you could get lucky and hit your precise combination on the very first roll.  You’d need lots and lots of luck.  Your odds of hitting the right combination on any given toss would be 1 in 1.6 novemdecillion. 

Now, admittedly, our test is very simplified compared to real life.  For one, at any given time the natural mutation process is likely to affect only a small number of the base pairs, if any, and certainly not all of them at once.  In that sense, our experiment speeded things up.  And we kept our word to a given length, rather than allowing it to grow additional character positions, which would have lengthened the odds even further.

But now think about this.  The genome for our hypothetical test organism was only 100 base pairs long.  The smallest genomes we know about, such as those found in viruses and bacteria, are at least 2,000 times larger.  The human genome is 31 million times larger—3.1 billion base pairs in all.  To be assured of coming up with any one particular base pair sequence in a genome that large would require 4 to the 3.1 billionth power throws, using 3.1 billion dice at a time!  When I try to make my calculator spit out that number, it gives me a message that says OFLO, which I take to mean, “Oh, for the love of —”  When I try it on any of several web-based applications I found online, the result is “Infinity.”  In fact, I get that same result for any power over about 500.  Or, putting it another way, your odds of getting it right on any given toss would be 1 in 43100000000 (a percentage that also makes my HP 20s Scientific Calculator’s eyes cross).  And by the way, our human reproductive cycle takes considerably longer than one hour for a generation. 

And yet we’ve managed to get here in just 4 billion years.

All of that said, if you reject the idea that random chance is responsible for the wonder that is life in all its diversity, you cannot then conclude, from a scientific standpoint, that “God did it.”  The data for such a conclusion are not at hand.  Not yet, anyway.

There is another huge hole in what evolution can explain.  One of the basic tenets of modern physics is that the laws of the universe are the same everywhere.  For instance, our sun is not unique, and it functions along the same lines as other stars in galaxies as far out as we can see.  Similarly, chemical processes are universal in nature.  To use a more localized example, lightning strikes a tree, which bursts into flame.  It’s not the first time a tree has burned, nor will it be the last.  The fire may die out, but the chemical laws that created it remain.  The next time the conditions are right, fire will be seen again.  Nature doesn’t seem to do anything just once.  Yet, when it comes to life on Earth, that’s exactly what appears to have happened.   Sometime around 3.8 billion years ago, the conditions for life were right.  Life therefore erupted.  Yet it’s never happened again.  Every organism on earth belongs to the same “tree of life,” descended from a single-celled organism of some sort that formed billions of years ago.  What came before that single cell, and whether it was the first to arise from the lifeless soup of organic chemicals that gave it birth, we don’t know.  But we do know that there are no other “trees of life” on Earth.  In all of the billions of years since ours took root, there has not been another single instance of life creation that we know of.  Why not?  Life seems to have erupted the moment conditions were right, which happened very soon after the planet cooled.  Why has there never been another life-forming “Genesis” in all the billions of years since then?  What process created life, and then went dormant?  Such one-time, unique events are not how nature is supposed to work.  Doesn’t it say something that even though we have been able to duplicate the conditions of primordial Earth in the lab, those experiments have not led to the creation of life?  Where did that original spark come from?  It’s exactly as if the fire in the analogy above erupted one time, but no new fires ever broke out after that in any other place, even though the conditions for fire remained exactly the same, or even better.

And while we’re raising questions—what evolutionary survival-favoring function do tears serve?  Why do we grieve when we lose a loved one?  Why do we laugh when amused?  Why do cats purr?  Why do dogs wag their tails?  In what genetic mutations are such behaviors rooted?

In science, if an hypothesis doesn’t satisfactorily explain all the known facts, then it doesn’t fit.  Conversely, even hypotheses that do fit the facts sometimes have to be rejected in favor of new ones that explain the facts better.  And quite often, the discovery of new facts completely shatters old notions.  History shows that scientists sometimes vigorously resist such breakthroughs when they first occur.  Evolution itself is an example of that.  Now ID proponents cry out for evolutionary scientists to do better.  They’re not wrong to do so.  Scientists should listen. 

Proposition (an intriguing idea yet to be proved):  something is going on with genetic mutation and the forming of organs and organisms other than just random chance combined with natural selection.  What is it?  How does it work?  Scientists would do well to keep digging.  And they are doing so, following the leads wherever the day takes them.

Intelligent Design proponents should take fair warning, however, that even if some other force, agent, or principle ultimately is found to be at work, it doesn’t mean that force, agent, or principle “must” be a designer, “must” be intelligent, or “must” be God or an entity of any kind.  It’s tempting to say that divine intervention must be responsible for anything that science can’t immediately explain.  And indeed, there is a long history of scientists themselves chalking up stubborn mysteries to the Almighty.  No less that the great Sir Isaac Newton himself, in his groundbreaking work Philosophiae Naturalis Principia Mathematica, attributed some planetary motions he couldn’t quite explain to the guiding hand of God.  Later, physicist Pierre Laplace used better calculations to connect all the dots, and was able to explain the motions without referencing God.  Napoleon Bonaparte famously asked Laplace why he left God out.  “I had no need of that hypothesis,” Laplace is reputed to have said.  This anecdote contributed to the public’s notion that scientists essentially are godless.

Really, it’s not true.  Science is not the enemy of religion.  Nor does the reverse have to be true.  If you are religious, there is nothing blasphemous in the idea that God might choose to work within the rules of the physical laws He created.  Scientific discoveries lead us toward the creator, not away.  If you’re not a believer, then science itself may someday solve enough of the Universe’s mysteries to convince you.  Maybe not.  In any case, science will not be complete until it can answer, with scientific rigor, the questions the faithful have already found their own a way to resolve.


For more thoughts on the theme of God and his relationship to mankind, see my sci-fi novel A Journal of the Crazy Year.

©2014 by Forrest Carr.  All rights reserved.

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