Evolution and the Fossil Record
As the evolution-creation debate heats up, the amount of misinformation
passed back and forth increases. An important example of general interest
is contained in the letter by Robert Root-Bernstein 26 June, p. 1446). In
discussing the power of evolutionary theory, Root-Bernstein says: "In the
absence of evolutionary theories, any chronological ordering of the fossil
record would seem to be a possibility, and no means would exist to choose
one order over another." This statement expresses the common
misconception that paleontologists arrange fossils in a theoretically
reasonable order and then use this order to construct a chronology. In fact,
no evolutionary theory at all is required to use fossils for geochronology.
The best evidence is that the geological time scale in its modern form was
fully developed by about 1840-before Darwin's Origin of Species. The time
scale based on fossils was built by geologists who were creationists. Since
1840, many details have been filled in, but the basic sequence has remained
So, the geological time scale and the basic facts of biological change over
time are totally independent of evolutionary theory. It follows that the
documentation of evolution does not depend on Darwinian theory or any
other theory. Darwinian theory is just one of several biological mechanisms
proposed to explain the evolution we observe to have happened.
This is part of a more general problem. A large number of well-trained
scientists outside of evolutionary biology and paleontology have
unfortunately gotten the idea that the fossil record is far more Darwinian
than it is. This probably comes from the oversimplification inevitable in
secondary sources: low-level textbooks semipopular articles, and so on.
Also, there is probably some wishful thinking involved. In the years after
Darwin, his advocates hoped to find predictable progressions. In general.
these have not been found-yet the optimism has died hard and some pure
fantasy has crept into textbooks. This is illustrated by other statements in
the Root-Bernstein letter, such as: "Evolution postdicts certain immutable
trends of progressive change that can be falsified." This is simply not the
case! In the fossil record, we are faced with many sequences of change:
modifications over time from A to B to C to D can be documented and a
plausible Darwinian interpretation can often be made after seeing the
sequence. But the predictive (or postdictive) power of theory in these cases
is almost nil. The problem faced by the evolutionary paleontologist is not
unlike that of the stock market analyst. Both the stock market record and
the fossil record are complex Markovian time series wherein causal
interpretations after the fact are often possible but the predictive value of
theory is weak to nonexistent. In fact, the technical market analyst probably
has a better record than the paleontologist. This does not disqualify
evolutionary theory; it simply illustrates the difficulty of applying any
statistical theory to actual cases.
One of the ironies of the evolution-creation debate is that the creationists
have accepted the mistaken notion that the fossil record shows a detailed
and orderly progression and they have gone to great lengths to
accommodate this "fact" in their Flood geology.
DAVID M. RAUP
Field Museum of Natural History,
Chicago, Illinois 60605
17 JULY 1981 289
(Raup D.M., "Evolution and the Fossil Record", Science, Vol. 213, No.
4505, 17 July 1981, p289)
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