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What the Theory of Evolution SaysWith
the discovery of DNA, the genetic data bank, evolutionists were given new
hope that they might find evidence supporting evolution of molecules.
Darwin developed his theory at a time when little was known about the
chemical composition of plants and animals, even less about chemical
reactions within living cells, and nothing about the chemistry of genes
(DNA) and gene products (proteins). The
double helix structure of DNA, discovered in 1953, almost 100 years after
Darwin’s pioneering work, cleared up many mysteries.
Now we know that each gene is a section of a long DNA molecule
containing many genes. Genetic
information can exist in stable form for thousands of years, yet can be
copied easily when cells divide. Knowledge
unavailable to Darwin enables genetic engineers to manipulate DNA,
transform it from one species to another, and even clone animals.
Therefore, artificially (or directed) as well as naturally (or random)
occurring mutations on a single part of a DNA molecule are possible sources
of biological variation. What Evolutionists Say We Ought to See Evolutionists
say that evolution needs to make sense at the molecular level. If evolution were true, we ought to observe and explain many
things, including the following:
What We Actually Observe in Nature Microevolution is now observed in molecules, yet an orderly progression from one species to another is not clearly supported by biochemistry. Many mutations are known to be changes in a single letter in a message “written” on a long DNA molecule. For example, a person can become quite sick from having a slightly different form of some protein, like hemoglobin (the molecule that carries oxygen in our red blood cells). Biochemists can detect which part of the molecule differs from the normal protein and even pin the blame on a specific chemical change in the DNA of the gene for hemoglobin structure. Can
scientists prove that two kinds of animals are related by observing DNA?
Molecular biologist Christian Schwabe writes, “Molecular evolution
is about to be accepted as a method superior to paleontology for the
discovery of evolutionary relationships.
As a molecular evolutionist I should be elated.
Instead it seems disconcerting that many exceptions exist in the
orderly progression of species as determined by molecular homologies: so
many in fact that I think the exception, the quirks, may carry the more
important message.” Some
molecular biologists speak of evidence of directed evolution, not Darwinian
evolution. What Scientists SayEvolutionists expected that an improved understanding of mutations, amino acids and DNA should put their theory on firmer ground, but instead biochemistry has raised challenging new questions. Biochemistry has not confirmed macroevolution. Attempts have been made to use molecular clocks to tell us how long ago each species branched off from its common ancestor of a proposed evolutionary tree. But, these molecular clocks run at different rates for different species and for different positions along the DNA molecule. These differences produce very large uncertainties in time, and the data have not compared well to fossil records, so the molecular clocks usefulness is questionable. Denton
says, “The really significant findings that come to light from comparing
the protein’s amino acid sequences is that it is impossible to arrange
them in any sort of evolutionary series.
Thousands of different sequences, protein and nucleic acid, have now
been compared to hundreds of different species but never has any sequence
been found to be in any sense the lineal descendant or ancestor of any other
sequence. In terms of their
biochemistry, none of the species deemed “intermediate”,
“ancestral”, or “primitive” by generations of evolutionary
biologists, and alluded to as evidence of sequence in nature, shows any
signs of supposed intermediate status.”
Davis says, “…it has proved impossible to arrange protein
sequences in a macroevolution series corresponding to the expected
transitions, from fish to amphibian to reptile to mammal.” Explanation Offered by CreationistsCreationists
credit God with creation of everything that exists, down to the molecular
level and even the subatomic level. A
DNA molecule contains massive and complex “genetic information” which,
like a blueprint, specifies how one living cell is put together.
Molecular biologists speak of “messages” and whole libraries with
information “written” in the “DNA code” or the “language of the
proteins.” Lindsay wrote that
the “information in one cell would fill a thousand 600-page books; and,
this one cell can be used to reassemble the whole body…” Davis
says, “Darwinists have help such high expectations that biochemistry would
provide evidence of gradual change between taxonomic groups. However,
biochemistry has not provided that kind of evidence.” Behe
points to the structure of an organ, the human eye, which would not work
unless all its many components were integrated.
To illustrate the concept, Behe uses a simple mousetrap comprised of
five “well-matched, interacting parts that contribute to the basic
function, wherein the removal of any one of the parts causes the system to
cease functioning.” Behe
argues that no feasible evolutionary explanation exists for some
“irreducibly complex systems” [not only in organs, but] in even the
simplest cells and molecular systems.”
Behe argues that this challenges the whole idea of molecular
evolution. |