Recent Problems in Evolution - 1999

Table of Contents

The Adequacy of 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 (Donovan, S.K. and C.R.C. Paul, eds. 1998. The Adequacy of the Fossil Record. Wiley, Chichester, UK), 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.

Baumiller, T.K. 1999. Enough remains to work with. Science 283: 1271.

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Molecular clock says eutherian mammals diverged 130 million years ago - fossils indicate 65 million years ago
The molecular clock hypothesis suggests that certain orders of eutherian mammals diverge as early as 129 million years ago (Kumar, S. and S.B. Hedges. 1998. Nature 392: 917). However, the current study indicates quite clearly (from many thousands of fossils) that nearly all the placental mammalian orders appeared suddenly at the time of the Cretaceous-Tertiary boundary, 65 million years ago. Researchers analyzed the quality of the fossil record during the late Cretaceous period, and found that there were large numbers of fossils that make it extremely unlikely that eutherian mammals existed before that time. According to Dr. Foote, "If the record really stinks, almost every species you find will be from single fossils. But the empirical record is something like 10 to 100 times greater than what would be required to allow for a 65-million-year gap in the fossil record."

Foote, M. J.P. Hunter, C.M. Janis, and J.J. Sepkoski, Jr. 1999. Evolutionary and preservational constraints on origins of biologic groups: divergence times of eutherian mammals. Science 283: 1310-1314.

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Molecular clock problems again
Much of evolutionary theory is based upon the hypothesis that all organisms have evolved from previous ancestors and are, ultimately, related. Such a hypothesis would predict that related genes would show this evolution their structure. However, recent evidence shows that "molecular clocks" tick at different rates for different lineages and for different genes. For example, the gene that encodes superoxide dismutase has 5 times the Two nucleotides on opposite complementary DNA or RNA strands that are connected via hydrogen bonds.base pair Replacement of one nucleotide in a DNA sequence by another nucleotide or replacement of one amino acid in a protein by another amino acid.substitution rate in certain species of Drosophila (fruit flies) compared to other multicellular organisms. Another gene, "Odysseus," has "evolved" more in the last 500 thousand years than the preceding 700 million years (1000 times faster rate now than in the past). Although evolutionary theories are unable to explain or predict these variations, creationary science does explain these discrepancies. God designed living organisms, reusing and modifying some of the genetic designs, but not necessarily in a way that would be consistent with a molecular clock.

Strauss, E. 1999. Can Of or referring to the mitochondria, the organelles that generate energy for the cell.mitochondrial clocks keep time? Science 283: 1435-1438.

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Endosymbiosis model of Of or referring to the mitochondria, the organelles that generate energy for the cell.mitochondrialorigins questioned
For over 100 years, the prevailing evolutionary theory for the origin of mitochondrion (the organelle of the cell that "powers" the cell's energy needs) has been thought to be endosymbiosis - the idea that an parasitic bacterium somehow got incorporated into an early cell, eventually losing its ability to exist extracellularly and becoming completely dependent upon the host cell. However, new data, from a group of little-known protists (unicellular eukaryotes) has challenged this hypothesis. The problem for evolutionists is similar to that seen in other areas of evolutionary theory. Mitochondria are extremely complex organelles that are fully integrated into the functioning of the cell. Some of the genes that code for Of or referring to the mitochondria, the organelles that generate energy for the cell.mitochondrial components come from a small Of or referring to the mitochondria, the organelles that generate energy for the cell.mitochondrial genome, whereas most come from the nuclear genome. Of those genes that come from the nuclear genome, the informational genes are similar to those found in archaebacteria ("ancient" bacteria that have been in existence for billions of years) and the operational genes are similar to those found in eubacteria (bacteria that make up the vast majority of species in existence today). The assumption has been that a primitive eukaryotic cell (with a nucleus, but no mitochondria) acquired a primitive bacterium that evolved into mitochondria. However, there is recent evidence from a primitive, previously little-studied group of protists (Archezoa) that the theory is probably incorrect. These protists do not have mitochondria (unlike any other eukaryotes), but code for these Organic compounds made of amino acids arranged in a linear chain, joined together by peptide bonds between the carboxyl and amino groups of the adjacent amino acid residues.proteins in their nuclear genome. In addition, the diversity among eukaryotes (especially with regard to Of or referring to the mitochondria, the organelles that generate energy for the cell.mitochondrial genes) is so great that no single theory can account for the existence of all living eukaryotes. The evolutionists' solution to the problem can be summarized by the following statement:

The possibility has been raised more generally that the earliest branchings of the eukaryotic tree may all be suspect for similar reasons (34, 53), with both "early" and "intermediate" branchings actually collapsing to an unresolved radiation (polychotomy) (54). The emerging revisionist view of eukaryotic evolution is a scenario characterized by a massive and virtually simultaneous radiation (big bang) at the base of the eukaryotic tree, involving virtually all extant eukaryotic phyla (34).

Gray, M.W., G. Burger, and B.F. Lang. 1999. Mitochondrial evolution. Science 283: 1476-1481.

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Having a harmful of bad effect.Deleterious A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutation rate too high for humans
A recent study examined the A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutation rate for humans. Using "conservative assumptions" the authors found that the overall A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutationrates was 4.2 Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations per person per generation, with a Having a harmful of bad effect.deleterious rate of 1.6. When using more realistic assumptions the overall A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutationrate for humans become 6.7 with a Having a harmful of bad effect.deleterious rate of 3.1. Such a high rate should have resulted in extinction of our species long ago. They stated in their conclusion:

"The Having a harmful of bad effect.deleterious A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutation rate appears to be so high in humans and our close relatives that it is doubtful that such species, which have low reproductive rates, could survive if Relating to a permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutational effects on fitness were to combine in a multiplicative way."

The authors must rely upon a rare association of Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations, termed synergistic epistasis to explain why the numerous hypothesized Having a harmful of bad effect.deleterious Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations have not overwhelmed our genome. Instead of postulating the obvious (that the human genome is not as old as evolution would teach), evolutionists again are relying upon the improbable to retain the evolutionary paradigm.

Crow, J.F. 1999. The odds of losing at genetic roulette. Nature 397: 293-294.
Eyre-Walker, A. & Keightley, P. D. 1999. High genomic Having a harmful of bad effect.deleterious A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutationrates in hominids. Nature 397, 344-347.

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Natural selection's most famous example, the peppered moth, based upon bad science
The "evolution" of the peppered moth, Biston betularia, whose story is recounted in almost every textbook on evolution, now appears to be based upon spurious data. According to the standard account, only one version of Biston existed before the mid-19th century: a white variety, peppered with black spots. During the Industrial Revolution its numbers plummeted because it became easy prey for birds as it rested on the pollution-blackened trunks of trees. In its place a mutant, pitch-black form of the peppered moth began to thrive, as it could rest on tree trunks without fear of being eaten. Precisely as predicted by Darwin's theory of natural selection, this more fit mutant moth rapidly outnumbered the white version, reaching 100 per cent levels in some industrial areas. However, during the 1950's, naturalists discovered a resurgence of the white variety, thought to be the result of the Clean Air Acts.  Scientists soon discovered that the white variety flourished again well before the return of pollution-free trees, while the black type continued to thrive in areas unaffected by industry. In addition, experiments showed that neither variety of moth chooses resting places best suited to its camouflage. Despite 40 years of effort, scientists have seen only two moths ever resting on tree trunks - they never have landed consistently on tree trunks, but hide under branches! It looks like the evolution textbooks will have to be rewritten. Evolutionist Richard Dawkins dismissed the new data, saying that, "nothing momentous hangs on these experiments."

Matthews, R. 1999. Scientists pick holes in Darwin moth theory. Telegraph Group Limited March 14, 1999.

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Prebiotic Soups - "useful for paving roads"
A recent book review of The Molecular Origins of Life (Andre Brack, ed.) was surprisingly candid in its analysis of the classical origins of life research. In it, the author, Steven Brenner, made the following statement:

Prebiotic chemistry would produce a wealth of biomolecules from non living precursors. But the wealth soon became overwhelming, with the "prebiotic soups" having the chemical complexity of asphalt (useful, perhaps, for paving roads but not particularly promising as a wellspring for life). Classical prebiotic chemistry not only failed to constrain the contents of the prebiotic soup, but also raised a new paradox: How could life (or any organized chemical process) emerge from such a mess? Searches of quadrillions of randomly generated Ribonucleic acid: a chemical that directs the manufacture of proteins and sometimes codes for the genetic material within certain organisms.RNA The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences have failed to yield a spontaneous Ribonucleic acid: a chemical that directs the manufacture of proteins and sometimes codes for the genetic material within certain organisms.RNA replicator.

The failure of these methods has led researchers to now look at genetic The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences from living organisms to try to infer the The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequence of a molecule that was once simultaneously capable of self-replication and catalysis. So far, no candidates have been found.

Benner, S.A. 1999. Old views of ancient events. Science 283: 2026.

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Chickens trade reduced immunocompetence for beauty?

Recent research has shown that the size of the male chicken's comb is inversely related to their immunocompetence (larger combs result in reduced immunocompetence). According to evolutionary theory, male chickens would have immunocompromised their immune systems in order to develop combs attractive to female chickens.

Verhulst S, Dieleman SJ, Parmentier HK. 1999. A tradeoff between immunocompetence and sexual ornamentation in domestic fowl. Proc Natl Acad Sci U S A 96:4478-4481.

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Multiplying improbabilities - fish fins evolved multiple times?

The discovery of ancient fossil fish has required extensive revision of  theories of fish evolution. Previously, evolutionists assumed that all fish evolved from one ancestor. New fossils suggests that the unlikely evolution of pectoral and pelvic fins independently in different species of fish. The theory requires the simultaneous evolution of skin, bone and muscle in areas of the body that previously had none. According to Per Ahlberg of the Natural History Museum in London, "We're seeing an upsurge of fish which have character combinations that confound our expectations." Xiaobo Yu, a paleontologist at Kean University in Union, New Jersey stated that the fossils have "mind-boggling [features] that keep paleontologists and developmental biologists busy during the day and sleepless at night."

Pennisi, E.. 1999. From Embryos and Fossils, New Clues to Vertebrate Evolution. Science 284: 575-577.

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One dinosaur species found on multiple continents separated by hundreds of miles of ocean!

Scientists have found a dinosaur species, Allosaurus fragilis, dated to have lived in Colorado some 150 million years ago, also lived on the other side of the Atlantic Ocean, in Portugal, at about the same time. The new fossil was discovered by paleontologist Bernardino Perez-Moreno of the Universidad Aut�noma de Madrid and colleagues in 150-million-year-old rock formations in Leira, 155 kilometers north of Lisbon. The skeleton, of a juvenile dino, is incomplete, but has telltale bones such as the pelvis, vertebrae, and fragments of leg bones, including "unmistakable pelvic features unique to A. fragilis." One puzzle is how the Allosaurus wound up on two continents: The supercontinent of Pangea had broken up tens of millions of years earlier, and by 170 million years ago Portugal was separated from North America by a sea hundreds of miles wide. Geologist Alan Smith of Cambridge University, who specializes in reconstructing ancient geography said, "you cannot get rid of the central Atlantic between Africa and America at this time--the evidence is incontrovertible." No reasonable explanations are available from our evolutionist friends. Water wings anybody?

Staff writer. 1999. Random Samples. Science 284: 903.

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Is It Time to Uproot the Tree of Life?

The above is the title of a recent article in Science. Molecular biology is allowing evolutionists to examine the relatedness of numerous bacterial species, and recent results are nothing less than startling. Darwinian theory requires that all organisms are, ultimately, related to one another. Therefore, the genes of living species should demonstrate similarity based upon the point at which the species diverged from a common ancestor. Different kinds of genes (rRNA, in addition to the entire The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequences of a couple dozen species of microorganisms) from the microbial kingdoms have been analyzed in the attempt to provide molecular evidence for macroevolution. An initial publication last year showed that "Comparisons of the genomes then available not only didn't clarify the picture of how life's major groupings evolved, they confused it." Current taxonomy classifies all living organisms into three kingdoms; eubacteria ("common" bacteria), Archaea ("ancient bacteria that are best known for living in extreme environments) and eukaryotes (all other living forms, including us). The current crisis involves the classification of species of eubacteria and Archaea. Some of the data suggest that certain eubacteria are more closely related to Archaea, and that certain Archaea are not related at all. In an examination of 13 fully Determining the order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequenced genomes, including those of bacteria, Archaea, and the eukaryote, yeast, scientists found that each microbe shares between 77% and 17% of its genes with another organism, with no clear relationships between species. The results are so confused that some researchers are proposing a complete restructuring of the tree of life, including breaking up the Archaea and redistributing them among the eubacteria. Other researchers have suggested that eukaryotes are more primitive than prokaryotes (both eubacteria and Archaea). However, the fossil record does not support such an interpretation (prokaryotes clearly appeared before eukaryotes). Several researchers have blamed gene transfer between diverse bacterial species, and even gene transfer between eukaryotes and prokaryotes. 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.

Pennisi, E. 1999. Is It Time to Uproot the Tree of Life? Science 284: 1305-1307.

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Origin of Large, Beneficial Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.Mutations
Recent evolutionary studies "show how important large beneficial Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutationsare in the first stages of an adaptation," according to evolutionary biologist Doug Schemske of the University of Washington, Seattle. 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 Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations seem to occur (of course de novo creation is eliminated as a possibility) poses a problem, since these Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.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. "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." Dr. Orr has proposed a mathematical model to attempt to explain these data, although it is yet to be confirmed. It is remarkable how much data doesn't fit evolutionary theories, requiring the proposal of yet more new theories.

Morell, V. 1999. Size Matters: The Genes Behind Adaptation. Science 284: 2106.

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"Genetic Purging" (inbreeding) is not good for breeding out Having a harmful of bad effect.deleterious genes
Charles Darwin first documented that inbreeding of morning glories produced less viable offspring. But Darwin also found that after several generations of inbreeding, the morning glories recovered, producing a healthy, fertile line. Darwin couldn't explain the phenomenon, but in the 1980s, several researchers concluded that inbreeding purges Having a harmful of bad effect.deleterious genes from a population.

At a recent scientific meeting, however, two evolutionary biologists, Diane Byers of Illinois State University and Donald Waller of the University of Wisconsin, warned that this "genetic purging" strategy works inefficiently if at all. Reduced viability in inbreeding populations occurs in part because individuals in a small, inbred population are more likely to inherit two copies of rare, Having a harmful of bad effect.deleterious versions of a gene. In larger populations, the chance that one individual will inherit two copies of such genes is quite small, and those who carry only one copy don't express the negative traits. But the idea behind genetic purging is that, in small populations, the bad genes should gradually die out over time, because individuals carrying two copies of such genes are less likely to produce young. The current studies focused on "genetic purging" in plants. Overall, only 38% of the studies found any evidence of genetic purging. And even when purging occurred, it removed only about 10% of the Having a harmful of bad effect.deleterious genes.

Although the article discussed the potential use of "genetic purging" as a means to save endangered species, it has great significance in the study of evolution as a whole. First, the selection process was not through natural selection, but through intelligent design (human experimenters), which would optimize the efficiency of the process. Even with this additional edge, the results showed that the process of removing Having a harmful of bad effect.deleterious genes did not work. This is a problem for evolutionary theories, since speciation must remove Having a harmful of bad effect.deleterious Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations in order that new species do not continue to accumulate Having a harmful of bad effect.deleterious Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations that would reduce the fitness of a population. This is especially a problem for punctuated equilibrium, since the process is dependent upon genetic inbreeding in small populations. See related article, " Having a harmful of bad effect.Deleterious A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutation rate too high for humans."

Pennisi, E. 1999.  Deoxyribonucleic acid: the chemical inside the nucleus of a cell that carries the genetic instructions for making living organisms.DNA and Field Data Help Plumb Evolution's Secrets. Science 285: 192-193.

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Adaptive changes not traced to their molecular roots in genes and Organic compounds made of amino acids arranged in a linear chain, joined together by peptide bonds between the carboxyl and amino groups of the adjacent amino acid residues.proteins
According to Dr. Elizabeth Pennisi, "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 Organic compounds made of amino acids arranged in a linear chain, joined together by peptide bonds between the carboxyl and amino groups of the adjacent amino acid residues.proteins." This general statement characterizes much of evolutionary study, although this particular article describes a rather striking example of microevolution in action. The researcher, Shozo Yokoyama, an evolutionary geneticist at Syracuse University in New York, discovered that the ability of coelacanths to see in the murky depths in which they live is due to two single point Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations in the light-sensing pigment, rhodopsin. Normally, this pigment absorbs light best in the green wavelengths (500 nm). The subsitution of one A group of 20 different kinds of small molecules that link together in long chains to form proteins. Often referred to as the "building blocks" of proteins.amino acid changes the optimal wavelength to 485 nm and 478 nm for the second. These simple Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations allow the coelacanths to see in the blue light that penetrates to the depths of the ocean where it lives.

Pennisi, E. 1999. Gaining New Insight Into the Molecular Basis of Evolution. Science 285: 654-655.

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Botanical tree of life to be pruned?
A recent study, named "Deep Green" has examined the genetics underlying the classification of plants in order to make a more realistic "tree of life." The results of the 5-year study suggests that the current classification scheme is too simple, since the genomic evaluations do not fall into the usual evolutionary classification schemes. The new results suggest that plants should be broken into three kingdoms, instead of one (see similar conclusions for the microbial kingdoms). In addition, the study suggested that flowering plants were closely related to a tropical shrub called Amborella, which branched from primitive plants. botanist Brent Mishler says that "at least half the Linnaean classifications are wrong" (the Linnaean system groups species by the number and arrangement of their reproductive organs, the stamens and pistils).

Scientists from Deep Green are now suggesting that plants be named according to clade, or genetically related group - a system called the PhyloCode. For example, the herb Prunella vulgaris and hundreds of other plants might simply go by the name vulgaris, with a tag in some master directory that scientists could refer to for phylogenetic data. Kathleen Kron, a botanist at Wake Forest University in Winston-Salem, North Carolina stated, "A plant's rank is arbitrary, and naming it by clade is a far more relevant, practical way to go." I have heard many evolutionists complain that the creationists' biblical classification scheme of "kinds" is unscientific. Now, some evolutionists are advocating just this sort of classification scheme and removing the arbitrary classifications of families, orders, etc.

Brown, K.S. 1999. Deep Green Rewrites Evolutionary History of Plants. Science 285: 990-991.

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Little or no evolution in ecological niches at the species level
S recent scientific study suggests that ecological niches evolve little or not at all at the time of a speciation event. The study shows ecological niche differences suddenly appear at the level of biological families. These results confirm the creation model seen in the Bible, which describes God's creative activities occurring at the level of "kinds" (which are similar to the biological classification of families). See page Naturalistic Biological Change and the Bible.

Peterson, A.T.,  J. Sober�n, and V. S�nchez-Cordero. 1999. Conservatism of Ecological Niches in Evolutionary Time. Science 285: 1265-1267.

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One of the two sex chromosomes, carried by males (1 copy) and females (2 copies) in mammals.X chromosome The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequence variability 4 times greater in chimps than humans

Previous studies have shown that the Of or referring to the mitochondria, the organelles that generate energy for the cell.mitochondrial Deoxyribonucleic acid: the chemical inside the nucleus of a cell that carries the genetic instructions for making living organisms.DNA ( Genetic material found in mitochondria, the organelles that generate energy for the cell.mtDNA) The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequencesin chimpanzees are more variable than those in humans (1-3). A recent study has examined a 10,154- Two nucleotides on opposite complementary DNA or RNA strands that are connected via hydrogen bonds.base pair The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequence on the chimpanzee X chromosome and found that The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequence variability is four times greater in chimpanzees than humans (4), indicating a last common ancestor at least three times earlier than humans.

  1. Gagneux, P. et al. 1999. Proc. Natl. Acad. Sci. U.S.A. 96: 5077
  2. Morin, P. A. et al. 1994. Science 265: 1193.
  3. Wise, C. A., M. Sraml, D. C. Rubinsztein, S. Easteal. 1997. Mol. Biol. Evol. 14, 707.
  4. Henrik Kaessmann, H., V. Wiebe, and S. P��bo. 1999. Extensive Nuclear Deoxyribonucleic acid: the chemical inside the nucleus of a cell that carries the genetic instructions for making living organisms.DNA Sequence Diversity Among Chimpanzees. Science 286:1159-1162.

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Chirality still a problem for origin of life

Origin of life researchers are attempting to look for weak forces that might explain how life consists of left-handed A group of 20 different kinds of small molecules that link together in long chains to form proteins. Often referred to as the "building blocks" of proteins.amino acids and right handed sugars. Some of the "classic" mechanisms, such as circularly-polarized light from supernovae and other explosive astronomical events, have now been eliminated:

"And researchers have shown that such [circularly-polarized] light can skew chemical reactions toward producing one particular chiral molecule at the expense of its twin. But supernovae and other astronomical sources would generate both the left and right spinning forms equally and so would be unlikely to produce an imbalance in organic molecules."

Even these problems ignore the more fundamental problem of high radiation levels that would be produced by these astronomical sources that are incompatible with living organisms or even complex organic chemicals.

The weak nuclear force is the only fundamental force that is chiral in nature, producing particles that spin in one direction upon radioactive decay. Therefore, researchers are trying to find conditions that might influence the percentage of left and right enantiomers of A group of 20 different kinds of small molecules that link together in long chains to form proteins. Often referred to as the "building blocks" of proteins.amino acids formed during prebiotic conditions.

Researchers have found an inorganic chemical, called sodium chlorate, which forms chiral crystals, normally yielding left- and right-handed ones in equal numbers. These crystals contain arrangements of atoms that spiral either clockwise or counterclockwise through the crystals. Environmental factors, such as stirring the solution, produces crystals of one chiral type. When the researchers bombarded a solution of sodium chlorate with left-spinning electrons from a source of radioactive strontium, they wound up with an excess of right-handed crystals. And when they hit the solution with positrons, positively charged counterparts to electrons that have the opposite spin, an excess of left-handed crystals formed.

At first glance, these experiments would seem to offer a naturalistic mechanism for chirality in living organisms. However, sources of positrons are not found in nature, so one would not have any kind of mechanisms for producing left-handed molecules, such as A group of 20 different kinds of small molecules that link together in long chains to form proteins. Often referred to as the "building blocks" of proteins.amino acids. In addition, the formation of crystals in a solution of salt is not the same as formation of enantiomers during the synthesis of chiral compounds, such as A group of 20 different kinds of small molecules that link together in long chains to form proteins. Often referred to as the "building blocks" of proteins.amino acids. The author of the original article readily admits, "Whether this is involved in the generation of chirality in A group of 20 different kinds of small molecules that link together in long chains to form proteins. Often referred to as the "building blocks" of proteins.amino acids is pure speculation."

Service, R.F. 1999. CHEMISTRY: Does Life's Handedness Come From Within? Science 286: 1282-1283.

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