Wednesday, January 07, 2004

Evolution and Mormonism

Evolution has been a topic of much debate in many Christian churches, including the Church of Jesus Christ of Latter-day Saints (LDS or Mormon Church). Members fall into various categories: those who reject evolution outright, those that accept some principles of evolution, and those that accept the theory of evolution in its entirety thus far. I fall into the middle camp since I accept some principles of evolution such as adaptation and natural selection, but I find some parts of the theory problematic. However, I believe that the theory of evolution is currently the best scientific theory that attempts to explain how life began on Earth. I also don’t think that the theory of evolution necessarily precludes belief in God.

As an LDS biologist, I’ve taken several courses on evolution and I’ve extensively read papers on both sides of the evolution/creation debate. In this essay, I will focus mainly on the pro and cons of evolution and its place in LDS theology. The pros and cons of creationism will not be discussed here.

Natural Selection and Adaptation
First of all, I have no problem with the concepts of natural selection, adaptation, and speciation. Natural selection is basically the increase in a subset of individuals in a population of organisms based on their increased adaptability to their environment. Adaptation is the process whereby an organism’s physiological structure, function or habits change so as to allow it to survive in new surroundings. I’ve observed natural selection, adaptation, and speciation in the wild when I was working as a fish biologist in the US Forest Service. Several species of non-native trout were planted in Utah streams and lakes many years ago and over time, because of their increased adaptability to their environment, they pushed out the native trout species. I also observed the crossbreeding of farm-raised non-native rainbow trout with native cutthroat trout, resulting in a hybrid subspecies that has characteristics of both species. These are phenomenon that can be observed and documented.

Now where I start having problems is with the beginning of life on Earth and the emergence of today’s creatures from a primitive cell. This part of evolutionary biology relies many on the interpretation of the fossil record, the relatedness of genes, and experimental chemistry based on numerous assumptions about the conditions of prebiotic Earth. This type of science is more speculative because one draws conclusions about collected data without observing the actual processes that produced the data.

The RNA World Theory
The prevailing theory for the beginning of life is known as the RNA World theory. The genetic material within each of our cells is known as DNA, deoxyribonucleic acid, and forms double-stranded sequences of 4 different chemical bases. A related chemical compound also found within our cells, known as RNA or ribonucleic acid, forms single-stranded chains, and is involved in transcription and translation of our genes into the building blocks of our bodies, proteins. RNA is also the genetic material in some viruses. Typically, proteins called enzymes catalyze the chemical reactions that keep our cells running, but some unique chains of RNA have been shown to catalyze simple chemical reactions. Now because RNA is chemically simpler and can act as an enzyme in some cases, many scientists theorize that the first beginnings of life consisted of simple sequences of RNA catalyzing reactions, such as polymerization and copying of other RNA sequences, i.e. an RNA world.

The major problems with this theory are basically questions of organic chemistry and the natural selection and heritability of these molecules over time without the advantages of a full-fledged living cell. I won’t go into details of the chemistry, but I’ll outlines the basic problems that need to be solved in order for the RNA world theory to be more plausible. First, the prebiotic soup was thought to be composed of a mixture of various simple organic compounds, some possibly arriving by hitchhiking on meteorites. Assuming that all the chemical reactions occurred that are needed to form sequences of self-replicating RNA, how are the products of these reactions enriched and selected for when there are many competing reactions occurring at the same time? Second, all the chemical reactions needed for formation of self-replicating RNA sequences from simple organic compounds are highly improbable events. The prebiotic chemical reactions that are thought to have formed the basic building blocks of RNA have not been reproduced the laboratory as of yet. No known natural ribozymes can catalyze template-directed polymerization of RNA, although some have been artificially synthesized and selected for in several labs.1

In fact, the products of these hypothetical chemical reactions are so difficult to obtain (read improbable), that some scientists believe that an even simpler self-replicating system must have arisen first. Some scientists have suggested that amino acid / nucleic acid hybrids called protein nucleic acids (PNAs) or inorganic clays with self-replicating crystals as the first “living” organisms. Leslie Orgel, a prominent biochemist at the Salk institute, believes that PNAs or RNA are still too complicated.

"We want something really simple, like a polymer of aspartate and glutamate [two very similar amino acids]. Anything much more complicated than that is implausible. It's so hard to make RNA. If nothing simpler can replicate, that would be a strong argument for the existence of God."2

But the evidence for these theories is scanty and also left unexplained is how a PNA- or clay-crystal-based organism switched over to a DNA / RNA-based organism.

Another big problem for evolutionary biology is how the random organization of bases of RNA and later DNA coded for proteins that actually did something to increase the “organism’s” fitness. If you throw a jumble of amino acids together, most likely you’ll get proteins that do nothing except sit there in an aggregated mess. To put it bluntly, what we have for the beginnings of life is science’s best guess as to the chemical make-up of the prebiotic Earth and a long string of improbable events that somehow lead to an organism that was able to perform all the biochemical reactions to keep it “alive” and to be able to pass these traits onto its offspring.

After the first living cells appear in the fossil record about 3.9 billion years ago, then I have fewer problems with the theory of evolution. I think it is possible, though not highly probable for modern multicellular organisms to have gradually evolved from single-celled organisms, a process called macroevolution. I have often wondered if 3.9 billion years is sufficient time for modern organisms to evolve from a single cell via natural selection. But calculating the amount of time necessary for evolution of modern humans is a herculean task that involves numerous assumptions as to the rate or rates of mutation, and the ratio of beneficial to harmful to neutral mutations, and the rate of transmittance of mutations to offspring. David A. Plaisted, a professor of computer science at the University of North Carolina at Chapel Hill, performed such a calculation3 and concludes that his study neither supports nor disproves evolution based on his many assumptions. Basically he shows that both evolutionary biologists and creationists can both come up with answers to support their theories based on their biased assumptions. This seems to be a major problem in both evolutionary biology and creationism.

Some evidences in support of macroevolution include the homology (relatedness) of certain genes between distantly related groups and the discovery of transitional fossils. Humans share a 47, 63, 15, and 20% homology (relatedness of genes) with the fruit fly, the mouse, baker’s yeast, and Arabidopsis (a model plant organism), respectively4. Transitional fossils are defined as fossils of species that have morphological features that appear to transition between an older and a younger specimen of a particular family lineage. Some persuasive evidence for evolution of whales from four-legged land mammals are the recently discovered fossilized remains of Ambulocetus natans (estimated at 50 million years old) and Rodhocetus (estimated at 46 million years old)5 Both species have strong tails for swimming, but the former has weight-bearing hind legs while the hind legs of the latter are much smaller and useless for walking on land.

Of course, creationists might argue that the homology of genes between distantly related groups and the presence of seemingly transitional fossils supports their thesis that God created life. Homology might be explained by God’s use of the same tools (DNA and proteins) to create different species of organisms. So-called transitional fossils might be the remains of unique organisms that were in no way ancestors of today’s creatures. However, since science has not been able to prove the existence of God, I would not expect that the scientific community would prefer the creationists’ theories. Proponents of macroevolution predicted that transitional fossils would be found and molecular biology has shown that organisms classified as most closely related based on morphology are also most closely related genetically.

Evolution and Mormonism
While many Christians may have a hard time reconciling the theory of evolution and their belief in God, members of the LDS Church may have an easier time based on their unique theology. Although LDS members believe the Bible to be the word of God, they also believe that errors of translation may have occurred or that parts were lost. For example, the Hebrew term for day, yowm, used in the Torah creation account can be translated as a time or an age rather then the 24-hour day as translated in the King James version.6 Furthermore, they believe that the Bible is incomplete because revelation from God to man continues up to the present. More information as to how the world was created may be forthcoming revelation. In addition, some parts of the Bible including parts of Genesis should be read figuratively, not literally. For example, the word “created” in the creation account is could be thought to denote organization of matter rather than creation ex nihilo. Brigham Young, leader of the LDS church in the late 1800’s commented on the figurative nature of Genesis :

As for the Bible account of the creation we may say that the Lord gave it to Moses, or rather Moses obtained the history and traditions of the fathers, and from these picked out what he considered necessary, and that account has been handed down from age to age, and we have got it, no matter whether it is correct or not, and whether the Lord found the earth empty and void, whether he made it out of nothing or out of the rude elements; or whether he made it in six days or in as many millions of years, is and will remain a matter of speculation in the minds of men unless he give revelation on the subject.7

In addition, the LDS church has a different view on the nature of God. Contrary to the traditional Christian doctrine of the Trinity with God being formless and one in three, LDS members view God, his son, Jesus Christ, and the Holy Ghost as separate beings with the God and Christ having exalted bodies of flesh and bone. Joseph Smith also taught that God works in harmony with natural laws, rather than by supernatural means: “True science is a discovery of the secret, immutable and eternal laws, by which the universe is governed.”8 So it is not inconsistent for an LDS member to believe that God created the earth and everything on it, but also believe that evolution may have played some role in the creation. The theory of evolution is man’s attempt to explain the miracle of the creation in terms that are understandable to him.

Leaders of the LDS church have not really taken a stand one way or the other on theory of evolution, except with regards to the creation of man. In November of 1909, the First Presidency of the Church (President Joseph F. Smith and his counselors) released an official statement on the subject of the origin of man.

“…It is held by some that Adam was not the first man upon this earth, and that the original human being was a development from lower orders of the animal creation. These, however, are the theories of men. The word of the Lord declares that Adam was "the first man of all men" (Moses 1:34), and we are therefore in duty bound to regard him as the primal parent of our race. It was shown to the brother of Jared that all men were created in the beginning after the image of God; and whether we take this to mean the spirit or the body, or both, it commits us to the same conclusion: Man began life as a human being, in the likeness of our heavenly Father….”9

This statement seems unequivocal in its assertion that man was created by God, rather than evolving from lower organisms. Yet it does not deal directly with the question of how the other organisms arose. Many church leaders have since seemed to be content with letting scientists deal with that issue. The First Presidency under Heber J. Grant in 1931 stated, “Leave geology, biology, archaeology and anthropology, no one of which has to do with the salvation of the souls of mankind, to scientific research, while we magnify our calling in the realm of the Church.”10 So it seems that the debate between evolution and creationism is really a moot point in the LDS community. For as long as one acknowledges God’s hand in the creation, any theory is fair game.

1 Joyce, Gerald F. (2002) “The Antiquity of RNA-based Evolution.” Nature 418:214-221.

2 Koerner, David W. and Simon LeVay. Here Be Dragons: The Scientific Quest for Extra- Terrestrial Life. (Oxford, NY: Oxford University Press, 2000) pg.17.

3 Plaisted, David A. “Rates of Evolution.” A Creative Perspective. (Jan. 4, 2004).

4 Lesney, Mark. (2001). “Ecce homology: A primer on comparative genomics.” Modern Drug Discovery 4(11): 26-38, 40.

5 Hunt, Kathleen. (1997) “Transitional Vertebrate Fossils FAQ.” Talk.Origins Archive. (Jan. 4, 2004).

6 “The Days of Genesis for Those Who Can’t Read Hebrew.” Genesis Research. (Jan. 6, 2004).

7 Journal of Discourses, (Liverpool Publishers, 1873) 15: 127.

8 Times and Seasons 4:46.

9 Clark, James R., ed. Messages of the First Presidency, vol. 4. Bookcraft, 1970.

10 Ludlow, Daniel H., ed. Encyclopedia of Mormonism vol. 4. (New York, NY: Macmillan, 1992), pg. 478.

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