The Case for a Creator - Lee Strobel [130]
In my interview for Chapter Three, biologist Jonathan Wells had satisfactorily answered my objections to the Cambrian explosion, one of which was that transitional organisms may have been too small or soft to have left a legacy of fossils. Still, another possibility came to mind.
“Maybe,” I suggested, “some unexplained environmental phenomenon caused a sudden spate of mutations that accelerated the creation of new organisms.”
“That doesn’t solve the problem,” Meyer replied. “First, even assuming a generous mutation rate, the Cambrian explosion was far too short to have allowed for the kind of large-scale changes that the fossils reflect.
“Second, only mutations in the earliest development of organisms have a realistic chance of producing large-scale macroevolutionary change. And scientists have found that mutations at this stage typically have disastrous effects. The embryo usually dies or is crippled.”
Geneticist John F. McDonald has called this “a great Darwinian paradox.” 32 The kind of mutations that macroevolution needs—namely, large-scale, beneficial ones—don’t occur, while the kind it doesn’t need—large-scale mutations with harmful effects or small-scale mutations with limited impact—do occur, though infrequently.
I brought up another idea that has been offered by some evolutionists. “Why couldn’t mutations have occurred in an inactive part of the DNA, sort of a neutral area that wouldn’t have had any immediate impact on the organism?” I asked. “Then, after a long period of time during which these mutations could accumulate, a new gene sequence could have suddenly kicked in and created an entirely new protein. Natural selection would then preserve any beneficial effects this would have on the organism.”
This theory wasn’t new to Meyer. He responded by saying, “Keep in mind that these mutations would have had to occur by random chance, since natural selection can’t preserve anything until it confers a positive benefit on the organism. The problem is that the odds of creating a novel functional protein without the help of natural selection would be vanishingly small. There are now a number of studies in molecular biology that establish this. So this so-called ‘neutral theory’ of evolution is another dead end.
“There’s really only one explanation that accounts for all the evidence. In any other field of endeavor, it would be obvious, but many scientists shy away from it in biology. The answer,” he said, “is an intelligent designer.”
FITTING THE “TOP DOWN” PATTERN
The puzzle of the Cambrian Explosion quickly falls into place once the possibility of a purposeful Creator is allowed as one of the explanatory options. Even one of the explosion’s most vexing features—its so-called “top down” pattern of appearance—is efficiently explained by intelligent design.
Said Meyer: “Neo-Darwinism predicts a ‘bottom up’ pattern in which small differences in form between evolving organisms appear prior to large differences in form and body plan organization. For instance, you might imagine that pre-Cambrian sponges would have given rise to several different varieties. These varieties would have evolved over time to produce different species. As this process continued, wholly different creatures with completely new body plans would have emerged in the Cambrian era.
“Instead, however, fossils from the Cambrian explosion show a radically different ‘top down’ pattern. Major differences in form and body plans appear first, with no simpler transitions before them. Later, some minor variations arise within the framework of these separate and disparate body plans.
“This has completely stumped neo-Darwinists. Others have tried to explain it away by proposing big leaps of evolutionary change—the so-called punctuated equilibrium idea—but even this can’t account for the ‘top down’ phenomenon. In fact, punctuated equilibrium predicts a ‘bottom up’ pattern; it just asserts that the increments of evolutionary change would be larger. Yet if you postulate intelligent