Recent Problems in Evolution - 1992

Table of Contents

Evolution or presence of an autonomous syntax module is implausible

Darwinian evolution necessitates a contribution to reproductive fitness. Recent studies of aphasia and Parkinson's disease show that functional syntactic ability involves neural structures that also are involved in speech motor control and nonlinguistic cognition. The evolution or presence of an autonomous syntax module is, therefore, implausible. (Lieberman P. Brain & Language 43 (4): 768-74, 1992.)

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The lack of a universal genetic code is difficult to explain by evolution

Recently, there have been discovered many examples where the genetic code, formerly thought to be constant, is altered. This was first shown in 1979 by Barrell et al. (G. Barrell, A. T. Bankier, and J. Drouin, Nature [London] 282: 189-194, 1979), who found that the universal Sequences of three adjacent nucleotides on a strand of DNA or RNA that specifies the genetic code information for encoding a specific amino acid into a polypeptide chain.codons AUA (isoleucine) and UGA (stop) coded for methionine and tryptophan, respectively, in human mitochondria. Subsequent studies have shown that UGA codes for tryptophan in Mycoplasma spp. and in all nonplant mitochondria that have been examined. Universal stop Sequences of three adjacent nucleotides on a strand of DNA or RNA that specifies the genetic code information for encoding a specific amino acid into a polypeptide chain.codons UAA and UAG code for glutamine in ciliated protozoa (except Euplotes octacarinatus) and in a green alga, Acetabularia. E. octacarinatus uses UAA for stop and UGA for cysteine. Candida species, which are yeasts, use CUG (leucine) for serine. Other departures from the universal code, all in nonplant mitochondria, are CUN (leucine) for threonine (in yeasts), AAA (lysine) for asparagine (in platyhelminths and echinoderms), UAA (stop) for tyrosine (in planaria), and AGR (arginine) for serine (in several animal orders) and for stop (in vertebrates). All of this unusual coding is a result of A small RNA molecule that transfers a specific amino acid to a growing polypeptide chain at the ribosomal site of protein synthesis.tRNA Permanent structural alterations in DNA, consisting of either substitutions, insertions or deletions of nucleotide bases.mutations. A A small RNA molecule that transfers a specific amino acid to a growing polypeptide chain at the ribosomal site of protein synthesis.tRNA A permanent structural alteration in DNA, consisting of either a substitution, insertion or deletion of nucleotide bases.mutation which would alter the genetic code for an organism, would most likely be fatal, since virtually all 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 would be altered at once. This presents a real problem in terms of an evolutionary explanation. (Osawa S., Jukes TH., Watanabe K. and Muto A. Microbiological Reviews 56 (1): 229-64, 1992.)

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The speciation process is still not well understood

"Called the 'mystery of mysteries' by Darwin, speciation is still a little-understood area of evolution." (Coyne JA. Genetics and speciation. Nature 355 (6360): 511-5, 1992.)

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A linear model for the evolution of H. sapiens remains obscure

Evolutionists have found it remarkable that the taxonomy and phylogenetic relationships of the earliest known representatives of our own genus, Homo, remain obscure. Advances in techniques for absolute dating and reassessments of the fossils themselves have rendered untenable a simple unilineal model of human evolution, in which Homo habilis succeeded the Australopithecines and then evolved via H. erectus into H. sapiens-but no clear alternative consensus has yet emerged. (Wood B. Origin and evolution of the genus Homo. Nature 355 (6363): 783-90, 1992.)

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Molecular clock rates of related species do not correlate

There is an extensive fossil record of post-Paleozoic echinoids, which allows rates of morphological change to be estimated over the past 260 million years and compared with rates of "molecular evolution." Data analysis has shown that morphological and molecular changes show a weaker correlation with one another. The molecular clock rate for echinaceans is three times faster than that for cidaroids and irregular echinoids. However, when just echinaceans are considered morphological change remains poorly correlated with molecular changes. Averaging results over all echinoids produces a correlation that is no better than the correlation between morphological change and time elapsed. (Smith AB., Lafay B. and Christen R. Philosophical Transactions of the Royal Society of London - Series B: Biological Sciences 338 (1286): 365-82, 1992.)

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No hominid fossil record before 5 million years ago

The lack of a hominid fossil record before about 5 million years ago--and any fossil record for the African apes is a frustrating barrier to evolutionists. (Andrews P. Nature 360 (6405): 641-6, 1992.)

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Paradox of the One of the two sex chromosomes that determines maleness in mammals, carried and passed down from males to males.Y chromosome

Evolutionists have suggested that mammalian sex Threadlike "packages" of genes and other DNA in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.chromosomes evolved from a homomorphic pair by the progressive loss of active genes from the One of the two sex chromosomes that determines maleness in mammals, carried and passed down from males to males.Y chromosome. Evolutionists have stated, "Among the changes that have accompanied this differentiation, it is difficult to determine causes, effects and correlates." (Graves JA. and Schmidt MM. Mammalian sex Threadlike "packages" of genes and other DNA in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.chromosomes: design or accident? Current Opinion in Genetics & Development 2 (6): 890-901, 1992.)

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Morphological analysis of the "living fossils" leads to confusion regarding origins of tetrapods

Meyer and Wilson (1990) provided a list of morphological features shared in common between modern lungfish and tetrapods, and they conclude that these traits were probably present in their last common ancestor. However, the exquisite fossil records of the abundant extinct lungfishes and rhipidistians show that at least 13 out of Meyer and Wilson's 14 supposed ancestral traits were not present in the last common ancestor of lungfishes and tetrapods. Modern lungfish are air-breathing nonmarine forms, yet their Devonian forebears were marine fish that did not breathe air. Morphological analysis of the "living fossils," the coelacanth and lungfish, has only lead to confusion regarding possible evolution of tetrapods. (Marshall C. and Schultze HP. Journal of Molecular Evolution 35 (2): 93-101, 1992.)

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Multiple origins for photosynthetic organelles?

Controversy exists over the origins of photosynthetic organelles in that contradictory trees arise from different The order of nucleotides in a DNA or RNA molecule, or the order of amino acids in a protein molecule.sequence, biochemical and ultrastructural data sets. The genetic differences between photosynthetic organelles has led evolutionists to propose the hypothesis of multiple origins for photosynthetic organelles, which seem extremely unlikely, given the complexity of these organelles. (Lockhart P.J., Penny D., Hendy MD., Howe CJ., Beanland J.T. and Larkum A.W. Controversy on chloroplast origins. FEBS Letters 301 (2): 127-31, 1992.)

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Heisenberg's uncertainty principle underlies the genesis of evolutionary variability?

One of the latest proposals for a mechanism for the theory of evolution involves Heisenberg's uncertainty principle. How directed evolution is obtained from this theory is anyone's guess. Here is the author's proposal, as he stated it. "Heisenberg's uncertainty principle in quantum mechanics underlies the genesis of evolutionary variability. When the uncertainty principle is coupled with the incontrovertible principle of the conservation of energy and material resources, there appears an uncertainty relationship between local fluctuations in the quantities to be conserved on a global scale and the rate of their local variation. Since the local fluctuations are accompanied by the non-vanishing rate of variation because of the uncertainty relationship, they generate subsequent fluctuations. Generativity latent in the uncertainty relationship is non-random and ubiquitous all through various evolutionary stages from abiotic synthesis of monomers and polymers up to the emergence of behavior-induced variability of organisms." Does this make sense to you? (Matsuno K. The uncertainty principle as an evolutionary engine. Biosystems 27 (2): 63-76, 1992.)

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Multiple catastrophic meteor impacts reveal life must have arisen within a period of less than 10 million years

Comparison of the dates of meteor impacts on the moon, Mercury, and Mars indicate that at least 30 catastrophic meteor impacts must have occurred on the earth between 3.8 and 3.5 billion years ago (1). It is clear that the size of the impacts would have sufficient energy to vaporize the entire ocean of the earth, resulting in the destruction of all life forms (2-4). One who believes that life arose spontaneously must now believe that life must arose from chemicals by chance at least thirty times in an average time frame of ten million years.

References

  1. Chyba, C. and C. Sagan. 1992. Endogenous production, exogenous delivery and impact-shock synthesis of organic molecules: an inventory for the origins of life. Nature 355: 125-132
  2. Maher, K.A. and D.J. Stevenson. 1988. Impact frustrations of the origin of life. Nature 331: 612-614.
  3. Oberbeck, V.R. and G. Fogleman. 1989. Nature 339: 434.
  4. Sleep, N.H., K.J. Zahnle, J.F. Kasting, and H.J. Morowitz. 1989. Nature 342: 139-142.

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Modern molecular genetics contradicts many evolutionary theories

The recent explosion in data obtained from molecular genetics has challenged many evolutionary theories. As one evolutionist has stated, "The results of molecular genetics have frequently been difficult to explain by conventional evolutionary theory." (Shapiro JA. Genetica 86 (1-3): 99-111, 1992.)

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Random existence of mammalian transposable elements

All mammalian transposable elements characterized to date appear to be nonrandomly distributed in the mammalian genome. While no element has been found to be exclusively restricted in its chromosomal location, LINE elements and some A type of virus that contains RNA as its genetic material. The RNA of the virus is translated into DNA, which inserts itself into an infected cell's own DNA.retrovirus-like elements are preferentially accumulated in G-banding regions of the Threadlike "packages" of genes and other DNA in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.chromosomes, and in some cases in the sex Threadlike "packages" of genes and other DNA in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes, 46 in all: 44 autosomes and two sex chromosomes. Each parent contributes one chromosome to each pair, so children get half of their chromosomes from their mothers and half from their fathers.chromosomes, while SINE elements occur preferentially in R-banding regions. No single model yet proposed is sufficient to explain all of the existing data on the nonrandom nature of locations of transposable elements. (Wichman HA., Van den Bussche R.A., Hamilton M.J. and Baker RJ. Genetica 86 (1-3): 287-93, 1992.)

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