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Walt Brown received a Ph.D. in mechanical engineering

http://www.creationscience.com/onlinebook

So you are quoting a mechanical engineer regarding biology.

I think I would rather have my cerebral aneurysm treated by a neurosurgeon than auto mechanic, but hey that is just my opinion

Now lets just review four of your points.

I know this is long but we need to be thorough so we can clear up these common misconceptions.

1. “Macro-evolution (organic evolution) has never been observed….”

Evolution, the overarching concept that unifies the biological sciences, in fact embraces a plurality of theories and hypotheses. In evolutionary debates one is apt to hear evolution roughly parceled between the terms “microevolution” and “macroevolution”. Microevolution, or change beneath the species level, may be thought of as relatively small scale change in the functional and genetic constituencies of populations of organisms. That this occurs and has been observed is generally undisputed by critics of evolution. What is vigorously challenged, however, is macroevolution. Macroevolution is evolution on the “grand scale” resulting in the origin of higher taxa. In evolutionary theory it thus entails common ancestry, descent with modification, speciation, the genealogical relatedness of all life, transformation of species, and large scale functional and structural changes of populations through time, all at or above the species level (Freeman and Herron 2004; Futuyma 1998; Ridley 1993).

Common descent is a general descriptive theory that concerns the genetic origins of living organisms (though not the ultimate origin of life). The theory specifically postulates that all of the earth’s known biota are genealogically related, much in the same way that siblings or cousins are related to one another. Thus, macroevolutionary history and processes necessarily entail the transformation of one species into another and, consequently, the origin of higher taxa. Because it is so well supported scientifically, common descent is often called the “fact of evolution” by biologists. For these reasons, proponents of special creation are especially hostile to the macroevolutionary foundation of the biological sciences.

This article directly addresses the scientific evidence in favor of common descent and macroevolution. This article is specifically intended for those who are scientifically minded but, for one reason or another, have come to believe that macroevolutionary theory explains little, makes few or no testable predictions, is unfalsifiable, or has not been scientifically demonstrated.

http://www.talkorigins.org/faqs/comdesc/

This goes into great detail and answers your entire question on this subject. I do strongly suggest that you take the time to read the entire article.

2 “The coding process of DNA simply doesn’t allow for macro changes…………..”

The Evolution Process

Evolution is the change with time of the gene pool of a species. The mechanisms of evolution are mutation, natural selection, recombination and gene flow.

Mutation provides all initial change. A mutation occurs when the DNA does not replicate perfectly. When a mutation occurs, a new allele is created. As a first approximation, these accidents (mutations) are random (can occur at any location along the DNA). The rate of these accidents is relatively constant within a given species. If the accident occurs in a critical location (believed to be less than 10% of the total in man), the result is usually disastrous. Other areas will accept change with no immediate consequence. Once made, the mutation is perpetuated and variability within the gene pool of the species is increased. Mutations add variability to the gene pool.

Natural selection occurs when the viability of an allele is tested in real life. It makes only one test. Contrary to popular opinion, evolution does not select the fittest, strongest, or most superior organism. It is instead a question of how many offspring the organism will have which in turn will reach sufficient maturity to have its own offspring. If the effect is positive, the allele will become a permanent part of the gene pool. If the effect is very successful, it will quickly become a dominant allele. If the effect is neutral or negative, the allele will not spread rapidly through the gene pool and, usually, will disappear from the gene pool. If more than one mutation is being tested at the same time, usually the case, then it is the summed effect tested. Not all good mutations make it. Some mutations would be good at one time and bad at another, depending on the environment then. A mutation that was necessary at one time may become unnecessary at another time and be consequently negated. Most of the time, the alleles removed or negated are those that harm the organism in that environment. Natural selection removes variability from the gene pool.

The environment which an organism faces and must survive is a complex one, one which is more than climate and food supply, although those are the essential elements that serve as a starting point in the study of evolution.

First of all, the mutation process is not altogether random. An intricate process called recombination developed early in sexual animals. This process serves to mix the alleles available in the two parental gene sets to provide more variability against the environment. It also results in many reproduction errors (mutations). Repair functions were developed by evolution for DNA errors to offset this error propensity. Since both the dissection means and the repair means are relatively fixed processes, then both the dissection errors and the errors in repair will follow certain patterns. When these coincide, a new allele is formed. Mutations, then, occur in clusters around particular loci not yet known or cataloged. Certain defects occur, therefore, with a given frequency, which are wholly the result of the process and not the assumption of a defective ancestral gene.

Another factor which enters into genetic change is that the product of a purely random process (and a large part of human mutations fit that description) will drift to one side or another until an outside force interferes with the drift. For example, the human is now growing larger. If this is the result of genetic drift, it will continue until some other process interferes, such as a shortage of food.

Most of the struggle in life is the struggle for enough food to avoid starvation and an ability to survive the climate. This was the entire struggle at the beginning, but as life became more complex, the selection process also became more complex. Once life began, however, other life became a part of its environment. The food chains were started.

The basic element of species survival is the ability of the individual to survive long enough to insure the survival of its offspring to the point when they also have offspring. If the offspring require no care, then the immediate death of the parent is of no consequence. In the case of the higher animals, those which require care during their maturation, the life of the caring parent must extend through that maturation period (and, of course, the parent must perform its function properly).

If an animal must endure an environment in which its population is normally controlled by predators, it is usual that the young suffer a higher death rate than the adults. In such cases the parents will usually live through several breeding seasons, to offset losses of their young. Some animals resort to large numbers of offspring, thereby feeding the predators, with enough left over to continue the species.

As animals became more complex, they themselves began to be an appreciable part of their own selection (survival) environment. Herein lies the most complex of all genetic processes, and examples abound. Sexual selection (based on an appearance which is sexually attractive) is probably (not for sure) the most common of these. There are times when sexual selection actually harms the ability of the species to survive. There are thousands of examples, but to select one, consider the Cardinal, a beautiful small bird that is quite common in North America. Somewhere back in time, the drab little hens, who had drab little roosters as soul-mates, took a liking to the color red and began choosing mates based on a hint of red in their feathers. Since they mated with roosters who had red in their makeup, their offspring tended to have red in their feathers, which suited the next generation of hens just fine. Quite quickly the rooster was a bright red, and the best target in the world for a predator. The predator, usually a hawk, could lock on to that bright red target and have a meal in no time. As a result the Cardinal rooster is quite skittish, and he should be, but without the red there is no sex and his genes end.

Recombination occurs in sexually reproducing organisms, such as the human. The parent has two sets of chromosomes in each cell, one from its father, the other from its mother. The sperm and the egg carry only one set in each. The one set carried by the sperm or egg is not a whole set from either grandparent but is a mixture of the two. Both original sets of chromosomes, in the case of each parent, are dissected and scrambled, then reformed with entirely new combinations of alleles from both grandparents. This process adds variability to the offspring and allows testing of new allele combinations. Recombination allows new combinations of the variability in the gene pool

Gene flow occurs when populations of a species that have been separated are united and the differing sets of alleles in each gene pool flow into the gene pool of the other. Our species, suddenly reunited with widespread transportation, is an excellent example of this effect. Gene flow distributes the variability in the gene pool.

http://www.onelife.com/evolve/evolution.html

3. “Have you researched Mendel’s Law too? Artificial distinction - NOT!………….”

Mendel (1822-1884) (the founder of Genetics) discovered how variation can be passed on through the generations with his work on pea plants (published in 1865-1869), yet his work was ignored until the early 1900s. Mendel discovered two laws: 1) the law of segregation, and 2) the law of independent assortment. The law of segregation states that half of the genes from one parent are carried by each gamete (sex cell). Each gamete has one allele (or one variation of a gene) out of two from the parent cell (each parent cell in a diploid species can have only two alleles at one gene locus — i.e. genes come in pairs in diploid organisms). The law of independent assortment states that different gene pairs assort independently of other gene pairs into gametes. As it turns out, these two “laws” have several exceptions to them. For example, the second law only applies to genes that are far apart on the same chromosome or are on different chromosomes.

At the turn of the century, after Mendel’s laws were re-discovered, two groups with differing views on evolution emerged: 1) the mutationalists, who believed that Darwin was wrong and Mendel was correct (i.e. evolution occured rapidly through macromutation), 2) the biometricians, who believed Mendel was wrong and Darwin was right (i.e. evolution occured slowly and gradually via natural selection). As it turns out, both Darwin’s and Mendel’s theories could be incorporated into one. The Modern Synthesis of evolution was developed around 1920 - 1947, unifying the principles from both Darwin and Mendel. Many people were involved in the development of the synthesis and these include Ronald A. Fisher (1890-1962), J.B.S. Haldane (1892-1964), Sewall Wright (1889-1988), Theodosius Dobzhansky (1900-1975), George Gaylord Simpson (1902-1984), and Ernst Mayr (b. 1904) to name a few. In Futuyma’s Evolutionary Biology (1998) textbook there are 20 tenets listed (pp. 26-27) that have been contributed by population geneticists, paleontologists, systematists, and geneticists who studied either laboratory populations or natural populations. Not all of the tenets are accepted by everyone, but the importance of the Modern Synthesis was in the “consistency argument” — the facts of genetics had to agree with the fossil evidence. Thus, the various biological fields became unified through evolutionary theory.

So, the modern paradigm of evolutionary theory is that natural selection acts on genetically different individuals in populations, thus species change over time. However, selection is not the only driving force in evolution. There are other forces such as genetic drift, gene flow, mutation and recombination (defined in “Basic concepts in Evolution”). Also, the modern paradigm rejects the notion of the “inheritance of acquired characteristics” or Lamarckism. There are however, some cases from embryology (developmental biology) and microbiology (e.g. experiments with ciliates) that provide evidence for inherited structural changes (i.e. not genetic changes) which are ignored by mainstream biology. I have posted a short essay that I wrote for an exam that summarizes some of the details.

http://www.geocities.com/we_evolve/Evolution/darwin.html

4. This is sometimes called the molecules-to-man theory—or macroevolution.

Charles Darwin never proposed a “molecules to man” theory. The theory of evolution has never attempted to describe the origin of the first living cell. Evolution merely describes the process whereby already existing life radiated into the diversity we see today.