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Evolution This was written by my 16 year old son in 1996.
It gives an overview of the biology of Evolution (this research paper
only briefly covers the evolution of man).
Notice it was for a language arts class!
It should also be noted that he wrote a wonderful research piece on
Joseph Smith for the same class, and both works were very well received. Collin Tungate Mr. Brail Language Arts II Honors 17 May 1996 Evolution In all of biology, the concept of evolution is one of the most important. Indeed, as Theodosius Dobzhansky said in 1973, “Nothing in biology makes sense except in the light of evolution” (Dobzhansky, et. al. N. p.). Unfortunately, it is seldom understood, much less accepted, by the general public. The theory of evolution is a combination of the works of the best minds in all facets of the field of biology, all put together to furnish evolution with the time, materials, and processes needed for complex organisms to have formed. Much evidence has arisen to provide evolution this foundation to work from. Perhaps the most astounding of all these was pushing down the religious mindset denouncing anything contradicting the Bible. In 1650, Irish archbishop James Ussher and several other scholars calculated, using the Bible, that man had been created at 9:00 A.M. on October 23, 4004 BC (Edey and Johanson 8). This date of six thousand year-old earth carried much weight and was accepted until the 1700’s, when James Hutton observed that the same things taking place now always have been taking place and always will take place—uniformitarianism. Hutton’s world was one “with no vestige of a beginning, no prospect of an end” (Edey and Johanson 20-21). Scientists have since radiometrically dated the oldest rocks at 3.8 billion years, and astronomical evidence indicates that the earth was formed at least 4.6 billion years ago. The oldest fossils are 3.5 billion years old, but there were almost undoubtedly organisms before that time, just with soft bodies that couldn’t fossilize (Towe 115). This is ample time for organisms to have reached the complexity they possess today. ] Time doesn’t mean anything unless the ancient earth was capable of producing and sustaining life. An analysis of the average composition of the universe shows the probable composition of the primitive earth to have been helium and hydrogen in large amounts (these elements are small and light enough for the majority to have escaped our atmosphere and gravitational pull) and methane, ammonia, and water vapor in smaller amounts (“Life” 1083G-1083H). Lightning and ultraviolet rays would have provided the energy that would bind the molecules together. All of the oxygen was locked into various chemical bonds, leaving none of it free. It wouldn’t be until much later with the appearance of chlorophyll-bearing organisms that oxygen would begin to make up as much of the atmosphere as it currently does. This scenario was first proposed by Harold C. Urey, and Stanley L. Miller used these conditions in an experiment that produced amino acids, the building blocks of proteins; ATP; and short nucleotides of RNA, necessary for life processes (Maitland and Johanson 284); thus proving that the basic components of life could be created in such an atmosphere. Most importantly, the mechanisms that natural selection performs upon have also been provided. Thomas Malthus, a social scientist, observed that, because populations grown geometrically but food supplies arithmetically, there is always a struggle for the available food, thus suggesting survival of the fittest (Maitland and Johanson 31). Gregor Mendel and his work in inheritance showed that characteristics are not swamped (overtaken by more common traits until the less common trait no longer exists) and also how genes could be passed down and preserved (Maitland and Johanson 105). Hugo de Vries discovered mutations (he found them in primrose flowers that weren’t actually mutating), showing how new and different genes could be produced. His work was backed up by Thomas Hunt Morgan and the Fly Room, where mutations (these were actually mutations) were induced, located, counted, and traced, and also by Alfred Sturtevant, who discovered crossing over and how to mathematically work out the frequency of it happening. James Watson and Francis Crick figured out the structure of DNA, which indicated how mutations occur (Maitland and Johanson 226). These all allow natural selection and, therefore, evolution to take place. “In everyday speech, ‘theory’ often means a hypothesis or even a mere speculation. But in science, ‘theory’ means ‘a statement of what are held to be the general laws, principles, or causes of something known or observed,’ as the Oxford English Dictionary defines it. The theory of evolution is a body of interconnected statements about natural selection and the other processes that are thought to cause evolution…. In contrast, the statement that organisms have descended with modifications from common ancestors—the historical reality of evolution—is not a theory. Like the heliocentric solar system, evolution began as a hypothesis, and achieved ‘facthood’ as the evidence in its favor became so strong that no knowledgeable and unbiased person could deny its reality” (Futuyma 15). So, while the theory of evolution by natural selection can never be proven, evolution itself is a fact, and there is tremendous evidence for evolution. This fact of evolution is shown in many ways. For one, the Linnaean binomial system of nomenclature shows the relationship between different organisms. This system of naming and categorizing was started by Carolus Linnaeus, and it gives each species a kingdom, phylum, class, order, family, genus, and species name. If they are organized into a family tree, one can view the evolutionary procession each organism took to get where it is today. The unity of life shows the same thing. Closely related organisms resemble each other in structure, development, and cellular composition. Homologous structures are different species with similar structures. For instance, the forelimbs of the penguin, the bat, the alligator, and the human, even though they look very different on the outside, are all derived from the same embryological structure and are strikingly similar in skeletal structure (Towe 223). Analogous structures have the same function but look different in structure, such as the wings of the butterfly and the bird. Vestigial structures are structures for which the original function is no longer needed nor used, yet the organ remains. The human ear muscles and appendix and the hind legs of snakes and whales are some obvious examples of this. The embryonic development is also very similar. Most embryos look the same early on in their development and then become increasingly dissimilar as they metamorphose into an adult. Many complex molecules and proteins are the same for all of life, and for these to have all developed in entirely unrelated ancestors is extremely unlikely. All of the above points to a common ancestor. Biochemistry and molecular anthropology show exactly how closely related species are and also give great evidence for a single predecessor. The immunological distance (ID) between species can be measured, showing the extent of difference between their respective blood proteins, and when compared to the ID’s of other species the degree of relatedness becomes clear. Such studies, started by Vincent Sarich, show the evolutionary relationships (Maitland and Johanson 363), and this can also be done by measuring the variations in the amino acid sequence of cytochrome c, a protein essential for aerobic respiration and DNA hybridization, which is the combining of half strands of DNA from two separate species and then seeing how much heat is needed to break up the new strands. “…The family tree drawn by serum albumin [the immunological distance] is a virtually exact match with one that would have been made by examining the bones, skin, size, shape, and behavior of living animals” (Edey and Johanson 358). The only differences are that this tree is more precise and it shows how closely related two species are. A similar family tree can be drawn by looking at genes that are widespread, and therefore probably existed in a common ancestor, and gene sequences that are diverse, indicating that changes have taken place recently and account for the variety in existing forms. Carl Woese has done exactly that, using genes of modern bacteria, and has constructed a family tree showing three branches: two bacterial branches and one leading to eukaryotic organisms (Edey and Johanson 311). Fossils are, of course, great evidence for evolution. “Fossil evidence indicates that over time organisms of increasing complexity appeared on the earth” (Rhodes 220). The evolutionary procession of organisms can thus be traced and dated using radioisotope dating, which is hyper-accurate up to a certain, known point, at which time other radioactive elements with longer half-lives can be used. A simple trace of primates shows human evolution. The trace goes from the Miocene Apes to Ardipithecus ramidus to Australopithecus, and then on to Homo habilis, Homo erectus, Homo sapiens neandertalensis, the Cro Magnon Man, and all the way to where we are now, Homo sapiens sapiens (Maitland and Johanson 325-368). The most important evidence is the evolutionary trends we have physically observed, for these cannot be denied or rebutted in any way. When Polynesian settlers brought bananas to the Hawaiian islands about a thousand years ago, banana-eating moths, unique to Hawaii and very closely related to other plant-eating moths, evolved (Towe 249). We saw, in fifty years, the peppered moths of Great Britain change from white with small black dots to black with small white dots when pollution became especially bad in the early 1900’s, and then change back as pollution lessened again (Towe 249). We have seen scale insects in California become resistant to the pesticide hydrocyanic acid (Rhodes 45). In just a short span of time Escherichia coli and other bacterium have become resistant to streptomycin (Rhodes 46). Bacteria is becoming increasingly resistant to penicillin. All of these we have seen, and the quick speed with which it proceeds is often scary. Hutton provided evolution the time; Urey and Miller the materials; and Malthus, Mendel, de Vries, Morgan, Sturtevant, Watson and Crick, and Darwin and Wallace the processes needed to fulfill its role in biology. The fact of evolution is proved and backed up by the Linnaean binomial system of nomenclature; the unity of life in structure, development, and cellular composition; biochemistry and molecular anthropology; the collection and study of fossils; and the evolutionary trends we have seen. With all this pointing towards or explaining evolution, how could one deny its existence as an important life function? Works Cited Dobzhansky, Theodosius, et. al. Evolution. San Francisco: W. H. Freeman and Company, 1977. Edey, Maitland A., and Donald C. Johanson. Blueprints: Solving the Mystery of Evolution. New York: Penguin Books, 1989. Futuyma, Douglas J. Evolutionary Biology. Sunderland, Massachusetts: Sinauer Associates, Inc., 1986. “Life.” Encyclopedia Britannica. 1970 ed. Rhodes, H. T. Frank. Evolution. New York: Golden Press, 1974. Towe, Albert. Modern Biology. Austin: Holt, Rhinehart and Winston, 1989. Personal Letter about evolution Brief History of Evolution as Taught by the LDS church Official
Positions of the LDS church GA
statements Death Before Adam by BYU Professor Steven Jones Evolutionary Biology - a primer Mormons
and Evolution More Material: http://eyring.hplx.net/Eyring/faq/evolution/ And even more material: More and more
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