Darwin's
Origin of Species established the fact that species are not immutable.
In one continuous and compelling argument he was able to transform the scientific
view of life from one that was fundamentally discontinuous into one that
was thoroughly continuous from ameoba to man, fish to philosopher. Perhaps
most significantly, he was able to convince many scientists of his day that
the geologic column developed by creationists decades earlier was actually
the result not of progressive acts of creation but rather of a purely materialistic
process he called natural selection. Although natural selection could account
for the survival of the fittest, critics pointed out that it could never
account for the arrival of the fittest. Be that as it may, Darwin put evolution
on the map.
The
term evolution has many meanings. It may refer to a population of light
and dark colored moths evolving into a population of dark and light colored
moths. It may refer to microevolution or it may refer to more significant
change - macroevolution. It may refer to speciation and the loss of ability
to interbreed. It may even take on elements of a secular religion where,
as the eminent zoologist Pierre-Paul Grasse
put it, "Directed by all-powerful selection, chance becomes a sort
of providence, which, under the cover of atheism, is not named but which
is secretly worshipped."
In
his book, Evolution and Myth of Creationism, Tim Berra uses the evolution
of the Corvette to make the point that everything evolves.
"Everything
evolves in the sense of "descent with modification," whether it
be government policy, religion, sports cars, or organisms. The revolutionary
fiberglass Corvette evolved from more mundane automotive ancestors in 1953
(1st image). Other high points in the Corvette's evolutionary refinement
include the 1962 model (2nd image), in which the original 102-inch wheelbase
was shortened to 98 inches and the new closed-coupe stingray model was introduced;
the 1968 model (3rd image), the forerunner of today's Corvette morphology,
which emerged with removable roof panels; and the 1978 silver anniversary
model (4th image) with fastback styling. Today's version (not shown) continues
the stepwise refinements that have been accumulating since 1953. The point
is that the Corvette evolved through a selection process acting on variations
that resulted in a series of transitional forms and an endpoint rather distinct
from the starting point. A similar process shapes the evolution of organisms."
(pp. 118-119)
(Photos
courtesy of General Motors Corporation)
Tim
Berra's illustration is important for a number of reasons. First of all,
notice that the term "evolution" is actually used in the sense
of progressive creation - a series of purposefully created automobiles.
While the survival of the fittest automobiles has much to do with competitive
selection, the arrival of the fittest was clearly the result of intelligent
design. Secondly, while the appearance of "descent with modification"
is common for created things like automobiles, computers, and computer software,
such evidence does not at all support the notion that "evolution"
was the result of purely unguided and unplanned natural processes. Indeed,
without continuous intelligent input, the evolution of the Corvette (which
follows a pattern of punctuated equilibrium - sudden appearence and stasis)
would never have been possible. Remove the intelligent input and one gets
stasis or lack of change.
Berra's
example of Corvette evolution is also important because it serves as an
analogy for some of the most difficult problems still facing Darwinian theory.
One
of those problems is natural selection itself. Although it is useful as
an explanation for microevolution, its ability to inhibit major evolutionary
change places it on a collision course with itself.
In
his book, Darwinism: The Refutation of a Myth, Soren Lovtrup points
out that,
"some
critics turned against Darwin's teachings for religious reasons, but they
were a minority; most of his opponents ... argued on a completely scientific
basis.
...the
reasons for rejecting Darwin's proposal were many, but first of all that
many innovations cannot possibly come into existence through accumulation
of many small steps, and even if they can, natural selection cannot accomplish
it, because incipient and intermediate stages are not advantageous."
Perhaps
the most formidable of Darwin's critics was St. George Mivart. His major
book, On the Genesis of Species (1871), took aim at the notion that
natural selection could account for the accumulation of the incipient stages
of useful structures. Stephen Jay Gould notes that
"Darwin
offered strong, if grudging, praise and took Mivart far more seriously than
any other critic...Mivart gathered, and illustrated "with admirable art
and force" (Darwin's words), all objections to the theory of natural selection---"a
formidable array" (Darwin's words again). Yet one particular theme, urged
with special attention by Mivart, stood out as the centerpiece of his criticism.
It remains today the primary stumbling block among thoughtful and friendly
scrutinizers of Darwinism. No other criticism seems so troubling, so obviously
and evidently "right" (against a Darwinian claim that seems intuitively
paradoxical and improbable). Mivart awarded this criticism a separate chapter
in his book, right after the introduction. He also gave it a name, remembered
ever since. He called it "The Incompetency of 'Natural Selection' to account
for the Incipient Stages of Useful Structures." If this phrase sounds like
a mouthful, consider the easy translation: we can readily understand how
complex and full developed structures work and owe their maintenance and
preservation to natural selection---a wing, an eye, the resemblance of a
bittern to a branch or of an insect to a stick or dead leaf. But how do
you get from nothing to such an elaborate something if evolution must proceed
through a long sequence of intermediate stages, each favored by natural
selection? You can't fly with 2% of a wing or gain much protection from
an iota's similarity with a potentially concealing piece of vegetation.
How, in other words, can natural selection explain these incipient stages
of structures that can only be used (as we now observe them) in much more
elaborated form?"
Stephen
Jay Gould
"Not Necessarily a Wing"
Natural History, October, 1985, pp. 12, 13
Gould
goes on to point out that among the difficulties of Darwinian theory "one
point stands high above the rest: the dilemma of incipient stages. Mivart
identified this problem as primary and it remains so today."
Back
to the Corvette.
Imagine
the steps necessary to transform the tube-type radio in the 1953 model into
the digital CD player in today's Corvette. One thing is obvious. The transitional
forms between the starting point and endpoint would constitute useless and
non-functional collections of components that would be eliminated in the
marketplace by competitive selection. Radios cannot be evolved into televisions
through a gradual step-by-step in the presence of competitive selection
nor can bicycles evolve into motorcycles on a step-by-step basis. What good
would adding a spark plug or a piston be to a bicycle until all of the components
necessary to produce an engine and drive train are in place? Even bacteria
have irreducibly complex rotary motors that propel them through their environment.
If it is not reasonable to believe that a relatively simple motorcycle engine
could be created by a gradual step-by-step basis, what logic would propel
us to believe that random mutations could lead to the first appearance of
a vastly more complex bacterial motor, particularly when "evolving"
bacteria would have to compete with other bacteria unencumbered with superflous
parts. Even Darwin admitted that natural selection should act to eliminate
such evolving creatures. (See
On
the Origin of Stasis)
If
relatively simple automobiles and computers required intelligent design
and continual guidance in their evolution, why should we assume that the
evolution of vastly more complex lifeforms required less intelligence?
Not
only are the fundamental predictions of Darwinian theory in opposition
to the pervasive patterns of the natural history, Darwin's mechanism of
natural selection actually does a better job of explaining why major evolutionary
change is inhibited from occurring on a gradual step-by-step basis. Michael
Behe's descriptions of cilia and bacterial flagella serve as illustrations
of how natural selection would act to eliminate the useless incipient
stages leading to irreducibly complex biological systems.
Despite
the major conflicts between Darwinian theory and natural history, it does
remain the best purely materialistic explanation of our origins. Once
any sort of intelligent design or divine intervention is ruled out of
science, Darwinian theory simply becomes the best "scientific"
explanation of biological diversity and disparity by definition. The best
"scientific" explanation for our origins is that we are the
result of a series of randomly generated mutations that have been selected
by a randomly generated environment. Let's
be honest. There is nothing like a good theory of origins and Darwinism
is nothing like a good theory of origins.
While
it is healthy to remain skeptical of the belief that major evolutionary
change is fully natural, we can be virtually certain that the phenomenon
of stasis is completely natural and subject to scientific investigation.
As Stephen Jay Gould put it, 'Stasis is data."
