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What
the Theory of Evolution Says
In his
pioneering work On The Origin of Species, Charles Darwin believed
that scientists would find fossils showing transitions from one kind of
animal to another. Darwin
assumed that strata (layers of sedimentary rock) are thick, continuous, and
old with the oldest records in the lowest layers and the youngest in the
uppermost layers. Life forms
would be preserved in those layers having the same age as the life forms;
hence, similar histories of strata in different locations, species
emergence, transition forms, and extinction records could be correlated.
Darwin was influenced by a geologist of his day, Sir Charles Lyell, who
argued that the earth was quite old and that geology is explained by uniform
gradual, not catastrophic, process currently observed.
That is called uniformitarianism.
However, Darwin argued that some geological changes occurred (in
agreement with 20th century geologists) and isolated species
environmentally. Darwin believed that this isolation might be important in
the production of a new species.
What Evolutionists Say We Ought
to See
Major geological
changes can cause new environmental conditions, including isolated
geographic regions, which might stress or favor a shift in surviving plant
and animal biological populations. We
ought to observe this shift by seeing fossils of transitional forms of plant
and animals. In the 1850’s, eighty years before geologists accepted the
theory of continents splitting and drifting apart, Darwin speculated that
this “splitting” had occurred. He
proposed that the earth had a long history of land being “united”, and
”divided again”, with far more change than from erosion, earthquakes and
volcanoes.
With so much change, species were geographically isolated in new
environments. Darwin thought
these changes could have brought about new kinds of plants and animals by
the “natural selection” of those that could survive. Key animals and plants unable to reproduce in new
environments would die out. If this were true, we ought to find remains or
traces of the continuously changing life forms, called ”transitional life
forms” by Darwin, over time in the fossil record.
What We Actually Observe in
Nature
Observations made of
large, sometimes catastrophic, geological changes have led geologists to
rethink the earth’s history. Asteroid
and meteorite impact, volcanoes, floods, atmospheric and oceanic circulation
patterns and temperatures, glaciations and tectonic plate collisions cause
the catastrophic changes usually referred to.
These events have been used to explain observations in geology and
paleontology and have been cited as important in both the formation and
extinction of species, especially the latter.
Dating of events in earth history is important in geology.
Modern geologists have measured the approximate age of the earth is
4.5 billion years old (much, much older than Lyell and Darwin thought) using
radioactive decays of various chemical elements present when the earth’s
crust was first formed. Dating
of the inverted “upside down” strata presented some special problems
because fossils were used to date strata.
Usually younger layers of the earth’s crust are on the top of the
older layers but not always. For some time now, suspected upside down strata have been
dated by the fossils found in the strata.
Some geologists cited by Morris say that circular reasoning may flaw
this approach, because evolutionary theory was assumed to date or sequence
the fossils from youngest to oldest. Other
geologists say that the process is not flawed.
They claim that occurrence of these upside-down strata is rare, not
the rule. The inverted strata
are disclosed by using fossils as time markers whose sequence is already
established by many examples of gradual deposited strata, not by any
assumption of evolutionary theory.
What Scientists Say
Modern geologists
have replaced Lyell’s ideas held 150 years, of the earth’s gradual
change (uniformatarianism) with belief in dynamic change, incorporating both
gradual and catastrophic change. These
geologists say that the deposition of sediments is a dynamic, not a
continuous process. Modern geology predicts that there will be an incomplete
fossil record and that the diversity of species may be related to isolation
of continents over time.
Darwin became aware that the geological record was insufficient and that its
interpretation did not always support his views. As he put it, one problem,
“namely the distinctness of specific forms, and their not being able to
blend together by innumerable transitional links, is a very obvious
difficulty.” He wrote, “ But as by this theory innumerable transitional
forms must have existed, why do we not find them embedded in countless
numbers in the crust of the earth?
This perhaps is the most obvious and gravest objection which can be
urged against my theory . . . it cannot be doubted that the geologic record
viewed as a whole is very imperfect.”
But Darwin recognized that not all species could be preserved.
“No organism wholly soft can be preserved.
Shells and bones decay and disappear when left on the bottom of the
sea, where sediment is not accumulating.”
ON THE FOSSIL RECORD: Professor D. S.
Woodruff (University of
California-San Diego) writes, "But fossil
species remain unchanged throughout most of their history and the [fossil]
record fails to contain a single example of a significant transition" (Science,
Vol. 208, 1980, p. 716)
Explanation Offered by
Creationists
All creationists believe that God was the
first cause in the earth’s geological formation and development.
Young-earth creationists challenge the findings and sometimes the
methods of geology. They point
out uncertainties in radiometric dating. Some say that the earth was created
suddenly and recently with features that may appear to look old.
They indicate that the Hebrew word yom is most often
translated as “day”. They
attribute many present-day geological features (such as rapid formation of
coal seams) to the flood of Noah in Genesis 6-9.
Dr. Henry and John Morris, foremost advocates of the young-earth
position are the founders of the Institute for Creation Research.
They label its beliefs in flood geology and six 24-hour days creation
as “creation science” or “scientific creationism” although some
creationists did not believe that either evolution or creation was a science
that could be proved.
Old-earth or “progressive” creationists such as Dr. Hugh Ross accept
current scientific dating methods. Old-earth
adherents say that the Hebrew word yom is translated as a long period
of time more than 60 times in the Bible.
For example, a “day” of creation might be the Bible’s way of
referring to a longer, indefinite period, suggests chemist Robert Fischer in
his book, God Did It, But How?
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