This is part 6 in a series on evolutionism and the problems that are associated with it. I pray that you will find the information helpful.
I) Introduction
1) Darwin’s Finches
A) This little bird has come to occupy a special place in the history of the
Darwinian theory of evolution.
B) The claim that these little birds demonstrate evolution in real time is made
because Darwinists believe that they have actually observed the process of
variation and natural selection.
C) The claim is made that they have and are observing the process of speciation..
II) Definition
1) Speciation is a term used by Darwinists to describe a process in which one species of
bird, animal, or plant evolves into 2 or more species.
2) The process of speciation is a key concept and is of central importance to the theory
3) Darwin’s original theory offered a single mechanism for the origin of species: the
natural selection of variations that exist from individual to individual.
4) At the beginning of 20th century the discovery of Mendel’s work on the mechanism of
genetic inheritance, and the phenomenon of mutation, were married to Darwin’s
original conception to give the neo-Darwinist theory; that the mechanism of evolution
is that natural selection is not just ordinary variations, but of genetic mutations.
5) In both of these cases, the theory is critically dependent upon, and intimately connected
to the idea of “species”.
6) What is a “species”?
A) Oxford English Dictionary defines “species” as;
“A group of class of animals or plants (usually constituting a subdivision
of a genus) having certain common and permanent characteristics which
clearly distinguish it from other groups.”
B) This definition seems perfectly straightforward. Yet the dictionary goes on to
add “The exact definition of a species and the criteria by which species are to
be distinguished (especially in relation to genera or varieties) have been the
subject of much discussion.”
III) Problems with defining the word species
1) The definition that is used in the dictionary is the commonsense or folk definition
that was adapted by biologists throughout the 19th century.
2) But with the advent of a more scientific, research-based approach to biology in the 20th
century it became clear that it was an inadequate definition.
3) It is particularly defective when used in any context involving the discussion of
evolutionary theories and mechanisms.
A) The most obvious and immediate problem is this; if members of a species
vary, how can you tell when one individual either is, or is not any longer, a
member of the species?
B) Better stated, when does one species become another, and what empirical test
can be applied to test our ideas?
4) Example of
A) Is a mule a horse or an ass?
B) Is it some kind of halfway house between the two?
C) Are the criteria used to decide its status arbitrary or absolute criteria, or do
they spring from some deep structural principle which reflects the way in which nature is truly organized?
D) Is it a matter of scientific opinion or scientific fact?
5) The definition of species that has been given is clearly inadequate in this case.
A) Within the definition, we have no way of empirically testing the idea.
B) The only test we have using this definition is the characteristics of the
animal that we observe. If 2 organisms have different characteristics that
seem to distinguish them from one another then it is supposed that they
are different species.
C) Yet many organisms of the same species have noticeably different
characteristics.
D) Examples
1) Ammonite fossils found in Blockley, England
a) There are 2 main kinds of ammonite. There are the fat ones
with 2 rows of knobs on the side (called Liparoceras) and
thinner ones with no knobs (called Aegoceras).
b) Occasionally, collectors have found a 3rd kind which is said
to be an intermediate between these two (called
Androgynoceras).
c) This 3rd kind resembles Aegoceras in the inner whorls (that is,
when it was young and the shell was first forming) but later on
resembles Liparoceras with its two rows of knobs.
d) This 3rd fossil was believed to be a different species than the
other two based upon the observable characteristics.
e) Yet upon further examination it was found out that the 3rd
species was in fact not a different species than the others.
The variation in characteristics was due to extreme sexual
dimorphism and therefore was not a different species.
2)Human beings
a) We vary greatly in matters of anatomical details such as the
number of fingers or toes, structure of internal organs, bones
in the wrist, number of pairs of ribs.
b) Would this, using the above definition of species, make us
different species?
3) The Elephant Man
a) Joseph Carey Merrick was born Aug. 5th, 1862
b) He had a medical condition which is still under debate
today. We are still not sure what was the reason for the
condition.
c) Yet, using the common definition of species, I think it not
difficult to assign Mr. Merrick to a different species then
Homo sapiens.
d) It is clear from the appearance of the physical characteristics
of both outward appearance and the skeleton that it should be
the case.
e) Yet he is assigned to the species of homo sapiens. Based upon the definition given for species this is not logical.
The reason why he is assigned to this species is the fact that he came from
the same species, homo sapiens.
E) These 3 examples should be sufficient to illustrate the problems with naming
a species. Individual characteristics are not sufficient by themselves.
6) New definition
A) Seeing the problems associated with the commonsense definition of species,
evolutionists have attempted to redefine the word.
B) The next definition to make its way into the debate was this;
“A species is a group of plants or animals that are able to interbreed and
and produce fertile offspring and are reproductively isolated from other
such groups.”
C) It would seem that this new definition has the advantage in that it provides
an empirical test and is a matter that could be decided by experimentation.
D) Yet as we shall see, the very feature that seems to be its greatest strength, its
empirical nature, turns out to be its greatest weakness. For in practice, the
definition is found not to be workable.
1) The test, able to interbreed and produce fertile offspring and are
reproductively isolated, is not applicable to plants and animals that
do not reproduce sexually such as sea squirts of self-pollinating
plants. This is a substantial fraction of the biological world.
2) The test cannot generally be applied to plants and animals that are
extinct and that are known only from the fossils.
3) The test has led to some inexplicable anomalies. There are some
breeding populations that are described as separate species and that
do not (or cannot) interbreed, but which are genetically identical.
4) There are also a few known counter examples.
a) The offspring between a horse and an ass (mule or hinny) should
be infertile. Yet a few cases have been reported of hinnies bearing offspring.
b) The domestic bull Bos taurus can be crossed with a North American buffalo Bison bison to produce a hybrid, the
cattalo, which is fertile.
E) Does any of this really matter? To the working biologist, no. They can
do their work without it. But to the neo-Darwinist and their theory it is a
concern of great importance.
1) Suppose that a Darwinist scientist wishes to make a case for
evolution from one species to another that depends on fossils.
How are they to make the case if the definition of what
constitutes the ancestor species and the descendant species cannot
be tested biologically?
2) This is not just an argument in principal, Mistakes can be made, as seen
earlier with the ammonites.
3) The important thing to remember is that this new definition is just as
subject as the original definition for just the same reason. It cannot
be empirically tested.
7) Still another definition
A) Since the definition that seemed to be plausible has been shown to be
defective, a new definition has come into play.
“ Groups of actually or potentially interbreeding natural populations which
are reproductively isolated from other groups.”
B) The important point to notice about the new biological definition of a species
is that it no longer insists on determining experimentally whether the creatures
in question can interbreed. It is enough that, for whatever reason, they do not do so.”
C) It is hardly surprising to find that Darwinist biologists feel free to describe
the Galapagos finches as individual species on the basis that they usually
choose not to mate and to describe to occasions when they do as “hybridization”. But it is from this kind of word play that all the subsequent
claims of speciation and evolution flow.
D) The claim made by Darwinists that speciation is an observed fact and can be
evidenced by numerous examples continues to be asserted. In reality it seems
everyone of these examples falls into one of two categories of pseudo-
speciation.
1) Speciation is claimed by the semantic ruse of dropping the rigorous
biological definition of what constitutes a species and substituting a
definition so ill defined that any subspecific variation can be claimed
as speciation.
2) The case where the number of chromosomes doubles, creating a sport. E) Neither case can give rise to evolution in the true Darwinian sense.
IV) The solution to the problem
1) The solution to these problems Darwinists have adapted are surprisingly simple.
2) First they draw a distinction between Macro evolution and Micro evolution.
A) Macro evolution is the new name to Darwinian speciation. It is the process
by which species (organisms so genetically different they can no longer
interbreed) come into being. This process occurs over millions of years
so it cannot be observed or made the subject of experiment.
B) Micro evolution is very much simpler. It is the change in frequency of variant
genes (called alleles) from generation to generation, and something that can
be observed. By defining Micro evolution in such simple terms, they are sure
of silencing any critics, for no one can disagree that variant genes do change in
frequency from generation to generation.
3) The next part is the clever part. When you get enough Micro evolution, you eventually
get Macro evolution. This proposition cannot be tested empirically for exactly the
same reason that the concept of Macro evolution itself cannot be tested. Once you have agreed with the first part of the proposition, it appears difficult not to agree with the final point.
4) In fact, this final proposition-that lots of Micro evolution adds up to one big
Macro evolution- is contradicted by every objection raised against neo-Darwinism in the past: that genetic homeostasis will prevent morphological change beyond a certain
point; that there is no evidence for gradual change leading to Macro evolution in the
fossil record; that billions of years are required to accumulate such Micro evolution
and so on and so on.
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