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> An Invitation to the Facts < Response to Chapter 3 of The Evolution Deceit 'Imaginary Mechanisms of Evolution' Part 3: Can mutations increase information content? Andya Primanda 2: Mutations cannot increase information content There is one memorable scene in Harun Yahya's film "The Evolution Deceit," in which arch-evolutionist Richard Dawkins was unable to answer a question from a creationist interviewer. He was challenged to give an example of a genetic mutation or an evolutionary process which can be seen to increase the information in the genome. Dawkins' silence was considered an inability to answer that question. (Dawkins himself regretted his refusal to answer that question and he offered a late answer (Dawkins 2002)). However, the interview (conducted by Keziah Productions, an Australian TV production house affiliated with the Christian creationist organization Answers in Genesis) is a plot to deliberately destroy Dawkins' reputation (Williams 1998). To date, there are some examples of completely novel features acquired through mutation and natural selection. A good example is the evolution of a Nylon-digesting enzyme in Flavobacterium sp. K172 (Thomas 2000). Nylon, a synthetic fiber, did not exist before 1937. A group of Japanese scientists discovered a bacterial mat in a factory pond, and found that the bacteria living there are able to digest Nylon. They replicated the process in the laboratory and discovered that the Nylon-digesting ability was caused by the appearance of an entirely new enzyme, nylonase, which was formed by a point mutation. Nylonase was not a changed version of an old enzyme; it cannot work on other substances. Therefore, this enzyme is an evidence of a new feature acquired through evolution. The information gained must be new, because nylon is a new substance, nonexistent before 1937. Can information arise from pure chaos? First, we must define what information is. Claude Shannon's information theory defined information as a decrease in the uncertainty of the receiver (Schneider 2000). Dawkins (2002) recognized three aspects of information: total information capacity, the capacity actually used, and and the information content. If translated to the genome, the first is the number of available sites (total amount of base pairs), the second is the amount of coding regions, and the third is the sequence of bases (genes). In Dawkins' words, genes contain information needed for its survival. An organism's genome is not 100% information; most of its capacity are filled with redundancies and noncoding DNA. There are processes which can increase information capacity of genomes, including addition of genetic material, gene duplication, chromosomal duplication, and polyploidy (Betran & Long 2002). Some advances in understanding information gain in evolution come from the field of artificial life research. These studies should be considered as theoretical advances, offering analogues to actual evolutionary phenomena. However, they offer an interesting insight into the problem of information in evolution. Adami et al. (2000) and Schneider (2000) have shown that within a complex environment, self-replicating entities whose survival depends on the information content of its sequence experience a decrease of informational entropy (uncertainty). Their chosen definition of genomic information is knowledge about the environment, which ensures success (fitness) of its bearer within that environment. Again, this definition implies that information content is relative, because the relevant information for one environment may be worthless in another. Any site in a genome is considered to have information content if it is conserved across generations (its content is not variable). The opposite of information is uncertainty. Indeed, Claude Shannon defines information as a decrease in uncertainty. Thus, an observed decrease in uncertainty can be considered as an example of information increase. Harun Yahya and some other creationists (e.g. William Dembski & Lee Spetner) said that mutations cannot increase the information content of a genome. We will see whether this claim fits the facts.
Both studies mentioned above use artificial organisms in a digital environment (Avida for Adami et al. (2000) and ev for Schneider (2000)). The artificial organisms have the capacity to self-replicate and generate random variation (mutation) in each generation. They are able to show that, if subjected to natural selection, the organisms' genomic information content increases and uncertainty decreases in each generation until a stable peak is reached. Mutation supplies alternatives for natural selection; natural selection then decreases uncertainty by preserving beneficial mutations and weeding out harmful mutations, reducing the number of alternatives. Therefore, in principle, mutation and natural selection can increase information content of a genome. Each cannot act alone; mutations without selection only increase uncertainty (Schneider 2000: 2797). This initial conclusion still needs further corroboration, especially from studies of actual organisms. REFERENCES Adami, C.J., C. Ofria & T.C. Collier. 2000. Evolution of biological complexity. PNAS 97 (9): 4463--4468. Betràn, E. & Manyuan Long. 2002. Expansion of genome coding regions by acquisition of new genes. Genetica 115: 65--80. Dawkins, R. 1998. The information challenge. http://www.skeptics.com.au/journal/dawkins1.htm Schneider. T.D. 2000. Evolution of biological information. Nucleic Acids Res. 28 (14): 2794--2799.. Thomas, D. 2000. Evolution and information: The Nylon bug. http://www.nmsr.org/nylon.htm Williams, B. 1998. Creationist deception exposed. The Skeptic 18 (3): 7--10. Yahya, Harun. 2001. The evolution deceit 6th ed. Kültür Publishing, Istanbul (Online pdf version at www.harunyahya.com) FEEDBACK Send feedback to: andya_p@postmark.net Previous page: Are
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