Existence - Random or with Reason?

Who are we...Why are we here...Time to take a few minutes and reflect

Introduction

 

This section examines the scientific basis for questioning the validity of macroevolutionary theories.

 

Definitions

 

It is important to first define what is meant by the word "evolution." There are actually two major theories of biological evolution:

  • Microevolution - Unequivocally proven through numerous scientific studies. Includes concepts such as mutation, recombination, natural selection, etc.
  • Macroevolution - Extrapolation of microevolution to account for all changes in body designs, speciation, appearance of new phyla, etc.

 

Therefore, I accept microevolution as a scientifically reliable theory, which describes the intelligent design with which organisms were endowed by their Designer. However, in contrast to the reliability of microevolutionary theory, macroevolution is not supported by the record of nature or current scientific research. Even evolutionists admit these major problems in the scientific journals (although you are unlikely to find these admissions in textbooks or popular books on evolution):

 

"Major transitions in evolution - such as the origin of life, the emergence of eukaryotic cells, and the origin of the human capacity for language, to name but a few - could not be farther from an equilibrium. Also, they cannot be described satisfactorily by established models of microevolution."1

Dr. Fagerstrom, et al.

 

There are two major models of macroevolution (In the remainder of this article, I will refer to macroevolution simply as evolution, since this is the common usage). They are:

  • Gradualism - Changes in the morphology of species are the result of gradual changes in the genomes of species. The apparent lack of gradualism in the fossil record is due to an incompleteness of the fossil record.
  • Punctuated Equilibrium - Changes in morphology are due to species sorting following geographic isolation and major reductions in population numbers. The punctuated appearance of the fossil record is real.

 

Refutation of Gradualism

 

The major problems with gradualism is that it is not reflected in the fossil record. By far, the fossil record is extremely discontinuous. There are a few examples of gradualism, but they are the exception. Even the most famous example of gradualism (the horse) suffers from a lack of intermediates for most species. Here is an admission by an evolutionist:

 

"Eldredge and Gould not only showed that paleontologists had been out-of-step with biologists for decades, but also that they had unconsciously trying to force the fossil record into the gradualistic mode. The few supposed examples of gradual evolution were featured in the journals and textbooks, but paleontologists had long been mum about their 'dirty little trade secret:' most species appear suddenly in the fossil record and show no appreciable change for millions of years until their extinction."2

Dr. Donald Prothero

 

The evidence against gradualism is extensive, but not readily admitted to in the popular press or textbooks. Although the fossil record for a given location on land may be discontinuous, the fossil record for organisms deposited in the ocean or large bodies of water is continuous. Studies by Stanley (3), Cheetham (4) and Stanley and Yang (5) examined all the available lineages of their respective groups (bryozoans and bivalves) through long intervals of time, using multivariate analysis of multiple character states. Both concluded that most of their species were static through millions of years, followed by the sudden appearance of new species. Williamson (6) examined the fossil record of mollusks in Lake Turkana, Kenya, and showed that there were multiple examples of rapid speciation and prolonged stasis, but no gradualism. Barnosky (7) examined a large number of different lineages of mammals, from mammoths to shrews and rodents that lived during the last two million years of the Ice Ages and found a few examples of gradualism, but many more which showed stasis and punctuation. Prothero examined all the mammals with a reasonably complete record from the Eocene-Oligocene (about 30-35 million years ago) beds of the Big Badlands of South Dakota and related areas in Wyoming and Nebraska (8). This study not only sampled every available lineage without bias, but also had much better time control from magnetic stratigraphy and wider geographic coverage than previous studies. With only one exception all of the Badlands mammals were static through millions of years, or speciated abruptly (if they changed at all). Stasis and sudden appearance of new species is the norm rather than the exception, as evidenced by the fossil record.

Evolutionists have used the excuse that the fossil record is not complete enough to be an accurate representation of the history of life on the Earth. A recent book, The Adequacy of the Fossil Record (9), examined the fossil record in terms of its completeness, bias (over and under representation of certain species and groups of organisms), and stratigraphic range (its completeness for a species over the entire history of its existence). Their conclusions were that the fossil record is surprisingly complete, with about 10% of all species that have ever lived being represented. There are some biases and stratigraphic incompleteness in the fossil record, but these problems can be estimated mathematically from the available data. There are many examples of stratigraphic gaps in the fossil record, with these gaps being the rule rather than the exception. In the past, it has been assumed that the gaps represent incompleteness of the fossil record. The authors suggest the "heretical" view that stratigraphic data should be used to test the phylogenetic relationships between species rather than assume that the relationships exist and that the fossil record is incomplete.

The punctuated fossil record applies not only to individual species, but to entire periods of time, where entire communities of species remain unchanged for millions of years. These periods of "coordinated stasis" can be followed by periods when "upwards of 60% of species seem to be replaced over a period of a few hundred thousand years"(10). During the first 16 million years of the Tertiary period, 18 orders of mammals appeared. Many scientist had claimed that gaps in the fossil record could account for the apparent sudden appearance of mammals. However, Dr. David Archibald (San Diego State University), looked at the numbers of fossil site spanning the period of 5 million years before and after the Cretaceous-Tertiary boundary. Dr. Archibald found that sampling was equal for periods before and after the boundary, although only 11 genera were found in the 5 million years before the beginning of the Tertiary compared to 139 genera in the 5 million years following (11). The idea that the lack of transitional forms is due to gaps in the fossil record is not reasonable given the tremendous number of fossils that have been discovered in recent studies. Therefore, the old "evolution of the gaps" theory is not supported by the extensive fossil record that now exists. Gradualism, although it seems a more logical mode of evolution, is not supported by the fossil record.

There are many who believe in the theory of evolution, who don't realize that you need to make a choice in what theory of evolution you are going to accept as being true. You can't believe in both gradualism and punctuated equilibrium simultaneously, since they are contradictory. Some of the "spokesmen" for evolution, such as Richard Dawkins, would like to redefine punctuated equilibrium into some sort of modified gradualism. However, the following statement is what Gould and Eldredge say about their theory:

 

"Punctuated equilibrium is a theory that attributes this pattern of spurt and stasis neither 1. to imperfections of the fossil record in a truly gradualistic world, nor 2. to such theories of occasional anagenetic rapidity as Simpson's important hypothesis of quantum evolution, but to speciation as a process of branching, characteristically occurring at geologically instantaneous rates - with trends then explained not as anagenetic accumulation, but as differential success by species sorting."12

Drs. Gould and Eldredge

 

The punctuated reality of the fossil record is best exemplified by the "Cambrian explosion." Virtually every animal phyla (including chordates and many phyla now extinct) appeared during the short geological moment called the Cambrian explosion (13). This period of time is now known to have covered a period of time of less than 10 million years (14, 15). The diversity of life and the variety of body designs has led Stephen Jay Gould to make the following statement:

 

"We have reason to think that all major anatomical designs may have made their appearance at that time."16

Dr. Stephen Jay Gould

 

Many evolutionists are now admitting that the diversity of life appearing at the Cambrian explosion is beyond what one would expect from any naturalistic mechanism:

 

"Understanding both the onset and the termination of such bursts is a major challenge. Critical tests for the trigger or damper of the Cambrian explosion have been difficult."17

David Jablonski

 

In a huge setback for evolutionists, scientists have discovered a true crustacean in early Cambrian strata from Shropshire, England. In a recent issue of Science, Drs. Siveter, Williams, and Waloszek. announced the discovery of a fossil phosphatocopid ostracod, which is preserved extraordinarily well, including all its delicate limbs cast in calcium phosphate, clearly allowing it to be classified as a crustacean. Dr. Richard Fortey, who believes that this discovery will foreshadow the discovery of pre-Cambrian ancestors of this crustacean, overturning the Cambrian explosion, has made this rather telling admission at the end of the article:

 

"Even if evidence for an earlier origin is discovered, it remains a challenge to explain why so many animals should have increased in size and acquired shells within so short a time at the base of the Cambrian. At the moment, there are almost as many explanations as there are animals caught in this belated "explosion."18

Dr. Richard Fortey

 

Other recent studies contradict the major mechanism behind gradualism, since they "show how important large beneficial mutations are in the first stages of an adaptation," according to evolutionary biologist Doug Schemske of the University of Washington, Seattle (19). According to evolutionary theory, a new adaptation must be acquired fairly quickly, or else organisms will be poorly adapted to both the new and the old conditions and will not survive. Therefore, it seems logical that the first genetic changes must have large effects or else the changes will not be selected. However, the observation that large beneficial mutations seem to occur (of course de novo creation is eliminated as a possibility) poses a problem, since these mutations are thought to be mostly rare and mostly disadvantageous when they do happen so "they contradict theory," according to Dr. H. Allen Orr, an evolutionary geneticist at University of Rochester in New York (19). "We're in a funny situation - we're about to have a wave of data crash down on us and no theory to hang it on." New models have been proposed to attempt to explain these data, although they are yet to be confirmed.

 

Refutation of Punctuated Equilibrium

 

Punctuated equilibrium requires the occurrence of two unlikely events. First, a number of beneficial mutations must accumulate in a small number of individuals. Since the mutation rate is low, the species' population must be large in order to accumulate any beneficial mutations (most mutations are neutral and the remainder are mostly detrimental). Next, these few individuals must become genetically isolated from the larger population (species sorting). Without genetic isolation (usually involving geographic isolation) the multiple mutations, needed to produce the punctuated appearance of a new species, would never get co-expressed. Therefore, punctuated equilibrium requires the unlikely events of multiple mutations in presence of a few individuals of large population, and the unlikely genetic isolation of these specific individuals from the vast majority of the main population. Although it is possible that such unlikely events could occur by chance occasionally, punctuated equilibrium requires that these unlikely events occur all the time, as revealed in the fossil record. Punctuated equilibrium truly is a faith in the miracles of chance.

A recent study destroys the idea of species sorting (20, 21). Instead of becoming a new species, populations that suffer drastic reductions in numbers are characterized by decreased genetic variability and an expression of detrimental genes. This happens because normally heterozygous (containing 2 different alleles of each gene) individuals become homozygous, due to inbreeding. As a result, detrimental, non-expressed, recessive genes become homozygous and, therefore, are expressed, resulting in a less fit population. The study examined the effect of a 35-year population decline of greater prairie chickens on their fitness and fertility. The results showed that population decline and isolation of the prairie chicken led to decreased genetic variability, reduced egg viability (from near 100% to less than 80%), and a decline of fertility rates (from 93% to 74%). Only after human intervention (which brought in genetically diverse individuals from other areas) did the population begin to recover. This study calls into serious question species sorting as the underlying mechanism of punctuated equilibrium. More recent studies have confirmed these results (22, 23).

Another study showed that low relatedness (high genetic diversity) is favored in social insects (24). This low relatedness improves the fitness of the colony, but prevents the kind of species sorting expected in punctuated equilibrium.

 

The Failures of Darwinism

 

Molecular Biology

Although molecular biology has been used to hasten research in many fields of biology, it has failed to confirm the evolutionary mechanisms proposed by Darwinian theory:

 

"Attempt to detect adaptive evolution at the molecular level have met with little success."25

Dr. Paul Sharp

 

"The results of molecular genetics have frequently been difficult to explain by conventional evolutionary theory"26

Dr. J.A. Shapiro

 

"Every step in evolution, from a darkening of a moth's pigment to the development of the opposable thumb, is caused by a change in molecules. But biologists have rarely traced adaptive changes to their molecular roots in genes and proteins."27

Dr. Elizabeth Pennisi

 

Several studies within the field of molecular biology have found major problems in the molecular clock hypothesis. This theory states that the rate of drift for a protein sequence depends on the number of amino acid residues that are critical for its function. Evolutionary theories state that non-critical amino acid residues should be substituted on a random basis through the eons of time. For example, the sequence divergence between humans and yeasts in histones (DNA-associated proteins) is only 3%, although mutational studies have demonstrated that approximately 30% of the sequence is non-critical to the function of the protein. If the molecular clock hypothesis were true, one would expect at least a 15-20% divergence between yeast and human histone sequences, given the length of time separating the last common ancestors of these unrelated species. (28)

With the recent advances in the field of molecular biology, DNA sequencing has become automated, and computer programs have been developed to analyze the large amount of data accumulated using such techniques. As a result, it has become commonplace to perform phylogenetic analyses of numerous species using a statistical method called likelihood ratio tests (LRTs). The use of LRTs has produced the following results in molecular evolutionary theory:

 

Testing Theories of Molecular Evolution Using LTRs

Evolutionary Theory Prediction

Result

Constant DNA substitution rate among lineages (molecular clock)

LRTs indicate that the molecular clock hypothesis should be rejected most often, since substitution rates vary widely among difference lineages of organisms (30).

A standard DNA substitution model explains evolutionary data

The current models of DNA substitution fit the observed data poorly (31).

The substitution rate is equal among nucleotides

This model usually does not match the observed data (32).

DNA substitution rates are constant among sites within a genetic sequence

DNA substitution rates vary widely among sites within a sequence (33).

DNA substitution rates are constant among genomic regions

DNA substitution rates vary widely among genomic regions (34).

DNA substitution process is identical among lineages

Methods of DNA substitution varied significantly among four of the major lineages that reportedly gave rise to present-day life forms (35).

The substitution process in the stem regions of ribosomal DNA is independent among sites

In fact, there is a correlation of substitution at pair-bonded stem sites in ribosomal DNA sequences (36).

The DNA substitution process is identical among genomic regions.

DNA substitution rates vary widely among genomic regions of transfer RNA from mitochondria (37).

Phylogenies for hosts and parasites are consistent with a common evolutionary history

For 13 sets of gophers and their associated lice, the phylogenies were different. In a small subset, they were consistent (37).

 

An analysis of the tree of life at its most basic level (kingdoms) indicates that organisms do not share common descent (38). A few dozen microbial genomes have been fully sequenced and the results indicate that there is no clear pattern of descent. Certain species of Archea ("ancient bacteria that are best known for living in extreme environments) are more closely related to species of eubacteria ("common" bacteria) than they are to members of their own kingdom. In fact, many microbial species share genes found in eukaryotes (non-microbial organisms characterized by the presence of a  nucleus in the cell). Many evolutionists are now suggesting that gene transfers were so common in the past (a convenient non-provable hypothesis) that a tree of life for microbial species can never be discerned from existing species. Such proposals remove evolutionary theory from being tested, and remove it from scientific criticism.

 

Human Descent

Modern molecular biology tells us that modern humans arose less than 100,000 years ago (confirmed by three independent techniques), and most likely, less than 50,000 years ago (39-48). This data ties in quite well with the fossil record. Sophisticated works of art first appear in the fossil record about 40,000-50,000 years ago (49) and evidence of religious expression appears only 25,000-50,000 years ago (50, 51). Such a recent origin date for modern humans precludes any possibility of any previous hominids being our ancestors, since Homo erectus died out 300,000 years ago, and Homo neandertalensis has been proven to be too genetically different from us to have been our ancestor (52). Where does this leave the evolutionists and their descent of man theory? Well, they can always fall back on their favorite line - "the fossil record is just incomplete."

 

"No one has actually witnessed the birth of a species in the wild, so researchers must come up with clever experiments to see whether differences in ecology, and the adaptations they spur, can isolate species reproductively."53

Dr. Virginia Morell

 

Climate and Ecology

Recent studies have shown that climate and ecology, supposedly the most influential driving forces of evolution, have had minimal effect on speciation. According to Richard Kerr, "But the best compilation of fossil evidence on mammal evolution to date now shows that climate had little effect on most of the evolutionary churning of the past 80 million years." Even the paleontologist who did the study, Dr. John Alroy said, "This is counterintuitive; I wanted to find a connection" (54). Paleontology tells us that there was a major change in the climate of Africa between 2.8 and 2.5 million years ago. Evolutionists have suggested that this change promoted early human evolution and a turnover of mammalian species at this time. However, a thorough study of mammalian fossils (over 10,000 specimens) from the period of 3.0 to 1.8 million years ago reveals that there was "no distinct turnover pulse between 2.8 and 2.5 Ma." Instead, the most significant period of change in mammalian species occurred between 2.5 and 1.8 million years ago (55).

Evolutionary theory predicts that much of the speciation of North American mammals and birds was influenced by the climatic changes and geographic isolation produced by the ice ages of the Late Pleistocene. However, in examining the mtDNA differences between songbirds, the predicted divergence rate of 0.5% is exceeded by a factor of 10 (the actual rate is 5.1%). Two possible evolutionary explanations exist to explain the data - either 1) the molecular clock is improperly calibrated or 2) climate and glaciation do not effect speciation. If the molecular clock were improperly calibrated, then for two groups of songbirds, the mtDNA divergence would have to be 50%, which the researchers describe as "highly improbable," given the likelihood of multiple substitutions at the same nucleotide position for such a high divergence. Therefore, it seems likely that climate and glaciation had little or no effect upon songbird speciation (56).

Geographic isolation, which has been hypothesized to result in speciation, has often been shown not to play a role. A recent study, using Japanese and Canadian stickleback fish demonstrated that thousands of miles of separation over long periods of time did not result in changes large enough to produce speciation. It was found that Canadian freshwater females accepted Japanese freshwater mates, and vice versa and that these crosses produced viable hybrids.

 

"We're trying to find what causes [speciation], and we're finding that geographic isolation by itself doesn't always provide the best answer. Something else is driving it--and we think that 'something else' is often the ecology."52

Dr. Patton

 

Although many evolutionists think ecology may drive speciation, the results from the studies cited above show that ecology often contradicts this viewpoint.

 

"At their best, Schlichting and Pigliucci's discussions force biologists to face a fact whose magnitude has been obscured by a good deal of wishful thinking: Our understanding of phenotypic evolution remains appallingly weak."57

Dr. Allen Orr (Department of Biology, University of Rochester)

 

 

Conclusion

 

As can be seen above, the logical predictions of evolutionary theories do not match the actual data. Either 1) evolution is a very random process that does not follow the usual rules of biology and chemistry or 2) life was not created through evolutionary mechanisms.

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