Facing Failed Predictions: Extinction, Not Biological Innovation, Explains Biodiversity

For many scientists, biological evolution is one of the most successful theories of all time. It is widely held that the evolutionary paradigm can fully account for the origin, history, diversity, and design of life. As the late geneticist Theodosius Dobzhansky proclaimed, “Nothing in biology makes sense except in the light of evolution.”1

Yet, in spite of this proclamation, the evolutionary paradigm cannot explain the origin of life or adequately account for key events in life’s history, such as the origin of phyla or the emergence of human exceptionalism. The theory of evolution has also had its share of failed predictions as evinced by the recent work of scientists from Germany and the United Kingdom.2

These scientists were trying to understand what caused the rapid increase in biodiversity for certain groups of organisms at specific points in life’s history. (Paleontologists dub these biodiversity bursts “radiation events.”) To unearth this cause-and-effect relationship, the researchers carried out a statistical study of the fossil record, using the origin and radiation of dicynodonts and sauropod dinosaurs as case studies.

In both instances, they discovered that these creatures didn’t experience a burst in biodiversity when they initially appeared on the scene. Instead, it was several million years later before these two groups underwent radiation events. In both cases, the bursts in biodiversity occurred after an extinction event. So, it wasn’t the biological innovation associated with the first appearance of dicynodonts and sauropods that initiated an increase in biodiversity. Rather, the trigger appeared to be the extinction of other groups of organisms.

These results came as a surprise to the researchers. According to Johannes Müller, one of the study’s authors, “We really did not expect any of these patterns. Our results go against many of the traditional predictions from evolutionary biology.”3

Facing Failed Predictions

Predictions are the cornerstone of the scientific enterprise. Scientists use them to assess the validity of scientific theories developed to explain aspects of nature’s workings. Scientists will consider theories valid only if they are in sync with current scientific data and if they successfully predict future scientific advances. Theories that repeatedly fail to make successful prognostications are cast aside—or, at least, they should be.

Evolutionary theory predicts that biological innovation should spark radiation events. According to the theory, when organisms evolve new biological capabilities, they should be able to exploit new environmental niches, or outcompete other members of their shared ecosystem. Yet, based on the work by the German and British scientists, this doesn’t appear to be the case.

What impact will this failed prediction have on the evolutionary paradigm? In reality, very little. Life scientists would prefer to appeal to ad hoc explanations for the patterns in life’s history than entertain the possibility that the evolutionary framework is wrong.

In the face of this failed prediction, the researchers proposed that while biological innovations don’t lead directly to increases in biodiversity, they do serve as a buffer that allows certain organisms to withstand the stresses associated with extinction events better than others. Hence, extinction events trigger bursts of biodiversity.

Yet given the calamitous circumstances that typically lead to large-scale extinctions, there is no reason to think that biological innovations would provide any more or less of an advantage in the face of wide-scale destructive forces. As a case in point, consider the asteroid collision with Earth that caused the Cretaceous-Paleogene extinction. The devastating nature of the impact wiped out an estimated 75 percent of all organism groups. It is difficult to imagine how any type of biological innovation would buffer against that type of catastrophe. In fact, most paleontologists think that contingent circumstances, not biological adaptations and innovations, determined which organisms survived.

The Restrictions of Methodological Naturalism

The evolutionary paradigm is not falsifiable in large measure because of philosophical considerations. The philosophical framework that undergirds contemporary science is known as methodological naturalism. This view asserts that only mechanistic, natural process explanations can be employed to explain the universe and its phenomena, such as the history of life. Any explanation that appeals to the work of an intelligent agent is forbidden—for philosophical considerations alone—regardless of what the evidence indicates. In this system, evolution must be true by definition and there is no possible alternative to the evolutionary paradigm. So even though this paradigm can’t account for the origin of life, the origin of phyla, and the origin of human exceptionalism, and even though it suffers from failed predictions, the theory of evolution can’t be abandoned. Why? Because no other option is permitted. The philosophical assumptions of contemporary science force the fact of evolution.

As an old-earth creationist and intelligent design proponent, I am not encumbered by the restrictions methodological naturalism places on the scientific enterprise. I maintain that it is possible to propose scientific theories that evoke the Creator’s handiwork. Because of this view, I’m willing to critically consider the evidence for and against the evolutionary paradigm. I would maintain that the evolutionary theory’s inability to account for the origin of life and several key events in life’s history and failed key predictions (such as the role biological innovation plays in generating biodiversity) provide sufficient reasons to be skeptical about the evolutionary paradigm. This theory’s failures also provide sufficient motivation to consider creationism and intelligent design models for the origin, history, and design of life.

Endnotes:

  1. Theodosius Dobzhansky, “Nothing in Biology Makes Sense Except in the Light of Evolution,” American Biology Teacher 35 (March 1973): 125–29.
  2. Neil Brocklehurst et al., “Elevated Extinction Rates as a Trigger for Diversification Rate Shifts: Early Amniotes as a Case Study,” Scientific Reports 5 (November 2015): id. 17104, doi:10.1038/srep17104.
  3. University of Lincoln, “Extinction is Key to Terrestrial Vertebrate Diversity, New Research Reveals,” ScienceDaily, November 23, 2015, http://www.sciencedaily.com/releases/2015/11/151123205755.htm.
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