Carina Nebula [Courtesy NASA] Ceililng of central rotunda, National Museum of Art of Catalunya

Are evolution and old-earth geology built on a "uniformitarian" assumption?

David H. Bailey
15 Jan 2012 (c) 2012

Introduction

In their literature, creationists and even an occasional intelligent design writer often claim that modern science in general, and evolution and old-earth geology in particular, are built on the shaky and unjustified foundation of a "uniformitarian" assumption. For example, creationist Henry M. Morris wrote "The evolution model is associated primarily with uniformitarianism, but evidence of catastrophism makes the uniformitarian assumption untenable [Morris2000, pg. 91-100]. Similarly, R. Albert Mohler, President of the Southern Baptist Theological Seminary, declared that "There is absolutely no reason that a Christian theologian should accept the uniformitarian assumptions of evolution." [Mohler2011].

The term "uniformitarianism" actually arose in the 19th century, when Charles Lyell published his multi-volume treatise Principles of Geology. The subtitle of this work was "An attempt to explain the former changes of the Earth's surface by reference to causes now in operation." The terms "uniformitarianism" and "catastrophism" were actually coined by William Whewell in a review of Lyell's book.

However, modern geology and biology have long since moved beyond these simple concepts, recognizing that while the earth's history is a slow process of gradual change, this process has been punctuated by periodic natural catastrophic events. For example, in the late twentieth century, J. Harlan Bretz demonstrated that the Scablands in eastern Washington state were formed from a large flood, which in turn resulted when a glacial lake broke through an ice dam. Similarly, in 1980, Luis Alvarez proposed that an asteroid impact was responsible for the extinction of dinosaurs 65 million years ago. Modern scientists are more apt to use the term "actualism" to refer to this combination of slow processes and catastrophic events [Isaak2007, pg. 161].

In articles on geologic ages (see Ages) we presented a chart with the various geologic eras and their ages. In the articles on radiometric dating (see Radiometric dating) and radiocarbon dating (see Radiocarbon dating), we briefly described how these dates are calculated using radiometric dating techniques. As we pointed out in those articles, these ages are based on known rates of radioactivity, a phenomenon that is rooted in fundamental laws of physics and follows simple mathematical formulas. In a related article on the reliability of radiometric dating (see Reliability), we discussed in detail how these methods have been tested and refined over the years, and why they deserve the trust that scientists place in them.

Rates of radioactivity

One key question that arises in this context is how can scientists assume that rates of radioactivity have been constant over the great time spans involved. In fact, this assumption has been tested at some length. Numerous experiments have been conducted to detect any change in radioactivity as a result of chemical activity, exceedingly high heat, pressure, or magnetic field. None of these experiments have detected any significant deviation for any isotope used in geologic dating [Dalrymple1991, pg. 86-89; Dalrymple2004, pg. 58-60].

Constants of physics

Scientists have also performed very exacting experiments to detect any change in the constants or laws of physics over time, but various lines of evidence indicate that these laws have been in force, essentially the same as we observe them today, over the multi-billion-year age of the universe. For example, the motion of stars in distant star clusters appears to follow the same laws of gravitation that we see in effect in our solar system and, for that matter, when apples fall from trees. Also, detailed studies of light coming to earth from distant stars (which, in many cases, emanated millions or even billions of years ago) reflects the same patterns of atomic spectra, based in the laws of quantum mechanics, that we see today in earth-bound experiments, confirming that these laws are in effect over wide ranges of time and space. For example, in supernova events that we observe in telescopes today, most of which occurred many millions of years ago, the patterns of light and radiation are completely consistent with the laws of quantum mechanics and the half-lives of radioactive isotopes that we measure in earth-bound laboratories today. For additional details, see Time machine.

As another item of evidence, researchers studying a natural nuclear reactor in Africa have concluded that a certain key physical constant ("alpha"), which is a key parameter in analysis of radioactive decay, has not changed measurably in hundreds of millions of years [Barrow2007, pg. 124-128]. A 2004 study suggested that "alpha" may have changed four parts in 100 million over the past 2.5 billion years [Reich2004], and a 2010 study suggests that alpha may have changed three parts in one million over a period of three billion years [Courtland2010]. A separate 2010 study suggested that alpha might vary by one part in one million over the observable universe [Brooks2010].

In September 2011, a team of European scientists made a rather startling announcement: they had clocked neutrinos traveling between the European Centre for Nuclear Research (near Geneva, Switzerland) and a laboratory beneath the Gran Sasso tunnel in Italy (a distance of roughly 454 miles) at a speed slightly faster than the speed of light, which is thought to be the ultimate speed limit of matter in the universe. In particular, they had clocked neutrinos arriving about 60 nanoseconds (or roughly 25 parts in one million) faster than a beam of light. Needless to say, an extraordinary claim of this sort requires extraordinary evidence, and this result will be very carefully scrutinized in the months and years to come [Overbye2011a; Overbye2011b].

But even if these variations in alpha and the speed of light are ultimately upheld (and they are highly tentative at the present time), they are several orders of magnitude too small to result in significantly different rates of radioactivity, or otherwise to have any material effect on the methods and conclusions of radiometric dating. Thus scientists are on very solid ground in asserting that rates of radioactivity have been constant over geologic time, and that the consensus dates of the geologic ages are reliable.

Summary

The young-earth creationist worldview would not only require that rates of radioactivity have changed measurably over the eons, but in fact that they have changed enormously -- by factors of a million of more. Needless to say, such enormous variations are utterly ruled out by all available data. In light of this data, the only reasonable recourse available to these creationists is to assert that prior to a few thousand years ago, the earth and universe were governed by utterly different laws, but that about 4000 BCE God altered the earth and universe to have an "appearance of age." But this "solution" is not a testable, scientific concept, and in addition presents huge theological problems as well -- see Deceiver.

In addition to the references mentioned above, useful information is available in online articles by Roger Wiens [Wiens2002] and Brent Dalrymple [Dalrymple2006]. For additional discussion, see Ages, Radiocarbon dating, Radiometric dating, Reliability and Time machine.

References

[See Bibliography].