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.
©2014 by Forrest Carr. All rights reserved.
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