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As noted, these are common anti-evolutionary arguments.
1. A living cell is the most complicated biological structure on earth. Formation of even one of the thousand components of the organisation within the cell by coincidences is impossible. The system that aims to distribute the proteins to sub-cell divisions is an example. It has been discovered that the head section of the proteins that would go to the golgi body and endoplasmic reticulum after being synthesized contains a special amino acid sequence called "signal sequence". When proteins are synthesized, a complex molecular structure called the Signal Recognition Particle (SRP) is integrated into the signal sequence. As a result of this, the protein synthesis stops temporarily. During this pause of the protein synthesis, SRP is connected to the SRP receptor on the cell membrane ensures the continuance of the protein synthesis and allows the entrance of the protein to the endoplasmic reticulum (ER). As the protein proceeds into ER, the signal sequence is cut off. This is only an insignificant part of the entire operations. Is the random formation of such a complex system possible? Let's assume that all the molecules mentioned here are formed randomly. ( they say this is also impossible) How can it be possible that this extremely complex organisation among molecules is formed on it's own?
The particular system described is only present in eukaryotic cells. Bacterial cells are much simpler, though still very complex. This reflects the ignorance typical of antievolutionary advocates. However, the question remains as to how complex molecular systems could be constructed by evolution and natural selection. First, it should be recognized that we know very little about complex molecular systems. Large-scale DNA sequencing has only been possible for less than 30 years. Most well-known bacteria are those that grow well either in a petri dish on agar or in us, neither of which is a habitiat found billions of years ago. Further, most of the work being done on these systems is by molecular biologists, who often don't know anything about evolution. Thus, the fact that many features remain unexplained often simply reflects a lack of effort.
At least two evolutionary proceses could build up a complex molecular system. First, the sequential addition of steps can produce a complex product. For example, suppose a proto-organism made an enzyme that could turn B into A. If B became depleted, an enzyme turning C into B would become useful, and so a chain could be built. Especially with a few billion years to fine-tune it, the final system might not have many traces of the original step-by-step assembly. A possible example of this comes from tRNAs. All living organisms depend on at least about 21 kinds of tRNAs to assemble proteins. However, several kinds of tRNAs are mutated copies of other tRNAs. Some ancestral organism must have been surviving just fine with a smaller set of tRNAs and thus fewer kinds of amino acids before the duplication and mutation occurred. Secondly, two existing systems can combine. The citric acid cycle is a complex, multistep process that is vital for most oxygen-dependent organisms. Each half of the cycle functions independently in certain bacteria.
"Random formation" is not exactly an accurate way of describing the process. Random has at least three meanings, and confusion of them is a major problem in the perception of evolution. First, there is mathematically probabilistic. Rolling dice, flipping coins, radioactive decay, and the occurence of a particular mutation are random in this sense. Secondly, there is humanly unpredictable, like long-term weather forcasting, the course of human history, or the course of evolution. These may be mathematically chaotic (i.e., theoretically predictable but so sensitive to initial conditions and perturbations as to prevent long-term prediction) or not governed by mathematical laws. Finally, there is purposelessness, as in random violence. Evolution is simply a natural process and so has no inherent purpose of its own, just as gravity has no goal. However, science cannot tell us whether God has a purpose for evolution; rather, this is determined theologically. The process of evolution is not random in the first sense because of natural selection. The probability that a mutation will spread through a population is closely correlated with how positive or negative is the effect of the mutation. Thus, good ideas are favored and bad ones generally lost. Furthermore, once one useful gene exists, duplication and mutation of that gene is more likely to produce a useful product than random generation of a new sequence. Not everything is assembled entirely de novo.
2. All the observed mutations either kill or harm living organisms. For example, countless experiments have been conducted on fruit flies (drosophila) until now and countless mutations have been applied on fruit flies over generations. However, none of them resulted in a man-made evolution. "Monster flies" formed by geneticists could not survive out of the bottle that they had been nurtured. They either died, became disabled or infertile. Legs emerged from their head. Besides, unlike those random mutations in nature, these were conscious and purposeful. But despite this, it has been impossible to form even one single enzyme. Therefore, could the complex body and organs of living organisms be formed as an outcome of mutation-like “accidents” ? How can we explain that mutations can do all these?
As previously noted, the initial claim (as well as most of the others) is false. The vast majority of mutations have either no effect at all or else very small effects. Small effects are about equally good or bad. Of course, it is possible to envision a situation in which almost any mutation would be harmful, and some antievolutionists try to use this to claim that beneficial mutations are really harmful because in other situations they are harmful. However, they also typically claim that the features of organisms reflect good design. (I believe that they do; the error is their denial that evolution is a method of designing). Any feature of any organism can be shown to be harmful in some situation. Also, only when competition is high do small variations in fitness make a difference. If competition is exceptionally low, wide variation in fitness may be tolerated.
Fruit flies in the lab have changed over time. This is man-made evolution. Some of the mutations could even be considered to have produced new orders and classes of arthropods. For example, the production of a second set of wings is contrary to the basic definition of a fly (order Diptera, di is two, ptera is wing). The production of a fourth pair of legs instead of antennae is contrary to the definition of insects (class Hexapoda, hex is six, poda is feet), and probably reflects a reversal to the ancestral condition for all arthropods. However, the only conscious and purposeful effort is in trying to produce more mutations than normal and in studying the mutations once they were produced. Only within the last few years has it been possible to produce a specific mutation, and even then we cannot tell exactly what will happen until we produce it. Many of the variations in fruit flies could survive perfectly well outside the bottle (and do when they escape; many biology buildings have a few odd fruit flies flying around in the building). I do not know, but would be highly surprised if no new enzymes had been produced by work on Drosophilia; certainly new enzymes have been produced in work on bacteria and viruses.
3. As a result of mutations, particles forming the genetic information break off, are destructed or moved to different parts of DNA. However, mutations can not contribute the living organisms with a new organ or new characteristics. But it can result in abnormalities such as the emergence of legs from the back or the emergence of the ear from the stomach... Has it ever been observed that mutations have increasing effects over genetic information of living organisms?
The definition of information is a problem here. However, the claims are self-contradictory. Legs coming from the back (of which I know of no examples) would certainly be a new characteristic, and the directions to make this would constitute new information.
Any mutation, whether a deletion, change of bases, rearrangement, or duplication of DNA, produces new information of some sort.
Dr. David Campbell
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