DARWIN'S   DILEMMA

Part I - Micro and Macro Evolution

By
Dr. Robert Gange

The name "Darwin" is synonymous with evolution. Yet evolution,
as a concept, traces back well before Darwin's time. Ancient
Norsemen believed that life evolved from slowly melting ice, and
that the process was fueled by breeze from a "land of fire."
Greek philosophers likewise held that life's advent was natural.
They viewed it as just another physical process. These old ideas
may have influenced Charles Darwin's grandfather, Erasmus, who
speculated in his book, Zoonomia that life may have evolved. But
unlike those of the past, Darwin was committed to the scientific
method. He also knew his Bible, and was married to a deeply
religious woman. But that did not keep him from abandoning his
views on Creation - a transition that began with a voyage.
 

DARWIN'S CHANGE OF HEART

In 1831, Darwin set sail on the Beagle. Leaving Devonport, he
traveled toward Patagonia. Before the trip Darwin believed that
Science reinforced the Bible's description of life's origin. The
geologists, cosmologists and biologists of the day concurred.
Virtually all of them believed that earth's history was the
result of supernatural happenings. But as Darwin traveled, he saw
things that changed his mind. He was also influenced by a book
that he read along the way: Lyell's Principles of Geology. This
book taught that small past changes accumulate to yield the
structures we see today. Darwin's studies lasted about five
years, and he left the ship convinced of two things: (i) The
Genesis account was not literal; and (ii) Evolution had occurred
in nature.

His first conclusion stemmed from observations he made
regarding formations in the earth's surface. He wrote, for
example, about huge vertical walls in a canyon several miles
across that was composed of very hard rock about three hundred
feet thick. Six thousand years was too short a time for natural
processes to produce what he saw. Changes caused by erosion, for
example, require centuries before they are even noticeable. Also
disturbing to him was the discovery that many species were
extinct. If Noah had taken all the species with him on the ark,
how could so many have perished in the short span of several
thousand years? Conversely, if the earth were very old, then the
opportunity might exist for one species to change into another.
Thus, for Darwin, the two ideas of a very old earth and the
creation of new species were related.

Darwin's belief in evolution was also fueled when he noticed
that insects common to South America and Europe landed on plant
life common to these same continents. Had God separately created
these plants and insects thousands of miles apart? Or did each
come from a single parent that underwent change in the past?
Analogous yet different species scattered throughout the
Galapagos Islands posed a similar question to Darwin: Were these
created as distinct species? Or had they evolved from a few life
forms common to the islands? He found, for example, over ten
different species of finches. Yet they looked like one another,
and they sang the same kind of song.
 

THE THEORY OF EVOLUTION

Although Darwin became convinced that change over long time
periods had produced life's diversity, he had no theory to
explain it. He completed his voyage after about five years. Two
years later, while reading Malthus's Population, Darwin pondered
the question: "Why does one species survive over another?"
Darwin's answer was that favorable changes are preserved and
unfavorable ones destroyed. He then assumed that the surviving
change created new species. Twenty years later, he wrote The
Origin of Species. This book synthesized notes from the voyage
with his idea that the fittest survive.

Prior to Darwin's publication in 1859, biologists believed
that life was created by God, that living structures were
designed, and that species were discontinuous and unchanging. But
Darwin's theory changed all that. Life was now the result of an
opportunistic combination from continuous random changes. In
effect, physical matter had replaced God, and good fortune rather
than design was the explanation. The survival of an opportunistic
combination was seen as the "natural selection" of a universal,
mechanistic materialism whose random motion never ceased. At long
last biologists believed that they understood life's diversity.
 

THE DEMISE OF OLD IDEAS

There were two lingering beliefs that had kept Darwin's ideas
from being accepted. The first was that each species of life on
earth is fixed and cannot change. The second was that the earth
is very young, and that its age is about 6000 years. But as
Darwin's discoveries became known to wider numbers of people,
these beliefs began to be seriously questioned, and their impact
decreased with each passing year.

What were these discoveries? Darwin observed that the
differences that separated certain dissimilar species were as
large as the differences he found among some domestic animals of
the same species. He argued that if such differences had occurred
in animals of the same species, then they could also arise to
separate animals into new and distinct species.

He further proposed how the changes occurred that created the
new species. Darwin argued that a virtual continuum of
evolutionary changes had occurred over long time periods, and
that a natural selection mechanism existed that favored the
"fittest" adaptations. New species then evolved from these
"favored" changes. His arguments proved persuasive, and the old
belief that species were fixed began to erode. But there was one
other problem. How could evolutionary changes occur over long
time periods when the earth was only 6000 years old?

One of the ways Darwin answered the age problem was an appeal
to coral growth. He observed that coral reefs slowly grow off
ocean floors. But they do so at depths no greater than about
twenty five feet below the surface of the water. How then, asked
Darwin, can some of these coral structures be hundreds of feet
high? He answered his own question in a most appealing way. He
supposed that the ocean floor had slowly sunk over eons of time,
and that the gradual growth of a hundred yard high coral reef
from the ocean bottom had occurred not by the coral reaching
great heights but, instead, by the ocean floor slowly dropping to
great depths. Explained this way, the earth was not thousands -
but millions of years old!

Here, then, was the removal of two great ancient beliefs that
had barred the acceptance of his ideas: The first, that species
are fixed and cannot change; and the second, that the earth's age
is 6000 years. With these two ideas aside, the old system with
fixed species and young earth was replaced by a dynamic evolving
edifice where mutations create new life forms over eons of time.

The implications of Darwin's synthesis were staggering. First,
life's advent and development did not need God. Second, religious
thought regarding creation and, by implication, all Scripture was
in error. Third, human life had no purpose and, therefore, no
destiny.
 

TWO KINDS OF EVOLUTION

In view of the foundational aspects of these inferences, it is
astounding that so little data has nurtured their acceptance over
the years. Even in Darwin's day, the evidence was purely
circumstantial. Consider, for instance, a similar structure that
is used in different ways i.e., the lever arm in a bat's wing,
frog's leg and man's arm. For Darwin these were not the single
design of a Supreme Intelligence, but the modifications of an
earlier structure that had evolved through natural selection.

Darwin also believed that the increase in the complexity of
life forms with time demonstrated evolution. These included
groups of existing species, as well as sequences of simple to
complex fossils in the geologic record. Darwin believed that,
given enough time, small changes produced new species, and that
they also produced new kinds.

These two ideas are known, respectively, as micro and macro
evolution - terms that have much broader application than
"adaption," which pertains to a modification that enhances an
organism's survival to a changed environment. Unlike
adaptation, which involves change within the same species,
microevolution pertains to the production of different species
within the same kind of life. For example, different species
of finches in the bird family. The second broad term,
macroevolution, pertains to the creation of different kinds of
life. For instance, the creation of sea life versus air life.

But it's here that we need a perspective. In Darwin's day,
living cells were considered to be as complicated as ping pong
balls. Darwin had no understanding of DNA or RNA. Yet if we
modeled a living cell today using objects as small as marbles, we
would need a room with a volume greater than 1000 cubic feet.
Darwin thus proposed a theory of life in a time period when
knowledge about its DNA blueprint was nonexistent. We are
therefore led to ask: How valid were his ideas?
 

MICROEVOLUTION

Two species of the same kind of life, and that may have
evolved from a common ancestor are the Black Backed and Herring
Gulls. The first is found in North America, and the second in the
Bering Straits. However, each species seems to undergo gradual
transition into the other as one travels from either location
toward that of the other. In Europe, which is about midway
between either location, the two species exist side by side and
do not interbreed. Yet if we leave Europe and travel either east
or west, the one species gradually diminishes until only the
other remains.

Another example of microevolution is the Hawaiian fruit fly.
Changes in the gene sequences along salivary gland chromosomes
indicate that over 500 species seem to be descended from less
than three colonizations. Over twenty species of a Hawaiian bird
(the Honeycreeper) likewise appear to have come from only one
ancestor.

Other examples could be cited to show that microevolution
appears to exist in nature. Two possible reasons for
microevolution are gene movement and genetic spread. The first
occurs from the more or less random interchange, insertion,
modification or altered duplication of genes. The second arises
from prior chemical information within the gene producing a
response at the molecular level to environmental change in a way
that enhances the organism's survival. Gene movement is a more or
less random process, whereas genetic spread is a "programmed"
adaption.

In this latter case, each species seems designed with a range
of genetic motion that ensures survival of the organism in
response to changing environmental conditions. Breeders have used
this genetic latitude to increase the sugar content of the sugar
beet, or the range of edible birds that have been bred from the
wild jungle foul. In times of drought, for example, genetic
spread permits a root to grow deeper, and its cuticle to thicken.
These and other similar changes, such as the thickness of a
mongoloid eyelid or the skin color in a negroid constitute
examples of genetic spread. But although these examples denote
change within the same species, the molecular mechanisms involved
can, in principle, gradually alter reproduction within isolated
populations over extended time periods. Were this to occur, a new
species could, in principle, arise - but it would necessarily be
of the same kind as the parent stock, and of a very similar
appearance. Possible examples might include the Black Backed and
Herring Gulls, or the Hawaiian fruit fly or Honeycreeper.

But microevolution can also occur from the motion of one or
more genes. The geographical distributions of similar species of
life have been examined across our planet. Some of these are a
mystery. But others can be explained by presuming that genetic
changes occurred within a fixed kind of life that disallowed
interbreeding of the modified organisms with the parent stock.
The current understanding of this phenomenon is that a small
portion of a given species is environmentally isolated from the
parent stock. Genetic changes within the altered environment then
occur. In some cases, the molecular alterations disallow
interbreeding. If the two groups are later rejoined, the failure
of the previously isolated group to interbreed is seen from a
taxonomic view as constituting a new species. If such changes
actually occur, it means that the process forms a new species
within a fixed life kind. The reason is that the term "species"
taxonomically means the ability to sexually reproduce.
 

DOES SCRIPTURE DISALLOW MICROEVOLUTION?

Does a process that disallows sexual reproduction among some
members of a given life kind contradict Scripture? The answer is
no. The Bible teaches that God created life after its kind - and
not after its species. The term "species" is a human label, and
it denotes one of a series of taxonomic titles created by man to
catalog life. Other titles include phylum, class, order, family
and genus. But the Bible uses the term "kind," and it defines
what it means. In Genesis 6:19-20, for example, Noah is
instructed to bring "every living thing of all flesh." God then
defines what He means: birds, animals, creeping things and (verse
18) man. But Noah was not told to take sea life with him. Genesis
chapter 1 also defines "kinds." They are: (v.20) Sea Life, (v.20)
Flying Creatures, (v.24) Animals (v.24) Creeping Things and
(v.26) Man. The term "kind" is also defined in the New Testament.
1 Corinthians 15:39 refers to men, animals, birds and fish. Since
the context of this passage is degrees of glory, it is not
surprising to find Creeping things omitted.

To summarize, the Bible defines five kinds of life: sea, air,
land surface, earth's interior and man. And it teaches that God
created each as a separate category, distinct from all others.
But Darwin's leap of faith extrapolated microevolution (genetic
spread) into macroevolution. He assumed that natural selection
had created man in the same way that it made new skin colors.

Genetic spread is a feature of life put there for its
survival. But macroevolution denotes an article of faith that has
no basis in fact. The uncritical acceptance of macroevolution by
numerous U.S. academic and professional societies has discouraged
critical examination of Darwin's ideas. Only recently have
these been shown to be without merit (1). Even so, much secular
thought implicitly presumes that if evolution has occurred in
some small degree, then it can occur without limit. In other
words, if microevolution has happened, then so has macroevolution.
However the problem with this idea is that macroevolution implies
changes to every component of the biological system. But if this
occurs, how can the organism survive? This question is largely
ignored by Darwin's supporters. Yet its affirmation undergirds
the validity of his proposals. In part II of this article, we
discuss the folly of Darwin's leap from micro to macroevolution,
and why natural selection cannot create new "kinds" of life.

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1. R.H. Brady - Nat Sel & Crit by which a Theory is Judged
Systematic Zoology 28:600 (22pp) (1979)

- Dogma and Doubt
Biol. Jour. Linn. Soc. 17(1):79 (18pp) (1982)