Reasons to Believe

Evolution Loses Its Equilibrium

Punctuated equilibrium doesn’t have a viable mechanism

This past Thanksgiving, my family and I (along with some good friends) rode down to the bottom of the Grand Canyon on mules. That night we ate dinner at the Phantom Ranch and the next day rode back out of the canyon. It was an amazing experience to be immersed in God’s creation—but also terrifying at times to be on the back of a mule maneuvering on rugged and narrow trails overlooking sheer drops of hundreds of feet. I was sure thankful my mule (Tin Man) had a good sense of equilibrium. If he didn’t, it would have been all over for both of us on a few occasions.

The evolutionary paradigm also depends on equilibrium (of sorts). Many paleontologists assert that biological evolution occurs by a non-Darwinian mechanism referred to as punctuated equilibrium. According to this view, biological evolution occurs rapidly—in spurts—followed by long periods of stasis.

Proponents of punctuated equilibrium posit that evolution only occurs when a small subpopulation of a species becomes isolated from the general population. If the isolated subpopulation becomes confined to the periphery of the species’ normal geophysical range, evolution will occur rapidly, say evolutionists, if the environmental and predatory pressures found in the periphery differ significantly from those found in the species’ typical geographical range. Experiencing different conditions, the peripheral subpopulation is not ideally suited for its environment. This mismatch provides the driving force for evolutionary change. When occupying its normal range, natural selection prevents a species well-suited for its environment from evolving. In other words, natural selection promotes stasis.

Punctuated equilibrium seems to explain the fossil record. If a new species emerges rapidly from a small peripheral subpopulation, it will seem as if that new species appears suddenly in the fossil record, and few if any transitional intermediates would be expected.

Even though punctuated equilibrium can explain the troubling features of the fossil record, one key question remains. Does the mechanism undergirding punctuated equilibrium actually work? Research results published in 2001 indicated, no.

Theoretical work by University of Oregon scientists shows that the essential processes making up punctuated equilibrium’s mechanism lead to extinction, not evolution. These scientists demonstrated that risk of extinction significantly increases for a species when its population becomes disconnected. Moreover, environmental changes and habitat fragmentation exacerbate a disconnected population’s susceptibility to extinction. Population and habitat fragmentation, along with an altered environment, stand at the center of punctuated equilibrium’s mechanism.

Investigators from Washington University in St. Louis produced field work confirming the work done by the scientists from the University of Oregon. Studying collared lizards in the Missouri Ozarks, the Washington University scientists showed that habitat fragmentation doesn’t drive speciation; rather it leads to extinction.

These two studies create a serious problem for the evolutionary paradigm. As discussed last week, strict Darwinian evolution lacks the necessary corroboration from the fossil record and cannot be declared a fact. Punctuated equilibrium “explains” the fossil record, yet fails due to the absence of a legitimate mechanism and must be rejected as an explanation for life’s history.

Though many evolutionary biologists would claim that I am off-balance, it seems to me that the absence of any conceivable naturalistic explanation for the origin and natural history of life’s major groups opens the possibility for the work of a Creator.

Subjects: Speciation Events, TCM - Speciation, Transitional Forms

Dr. Fazale Rana

In 1999, I left my position in R&D at a Fortune 500 company to join Reasons to Believe because I felt the most important thing I could do as a scientist is to communicate to skeptics and believers alike the powerful scientific evidence—evidence that is being uncovered day after day—for God’s existence and the reliability of Scripture. Read more about Dr. Fazale Rana