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Natural Selection and Evolution
Summary Booklet: KCC Creation & Apologetics Camp
4-6th August 2017
The History of Natural Selection
Ever since Charles Darwin published his famous book, “On the Origin of Species
by Means of Natural Selection” in 1859, natural selection has been considered
synonymous with evolution. With natural selection being observed and proven to
occur, many consider this as positive proof of evolution itself. The failure to
understand the distinct role of natural selection in evolutionary theory has
brought about – in public perception at least – the idea that any observed change
in a species over time is evolution at work.
Natural selection certainly does play a key role in a
general theory of evolution. Darwin envisaged natural
selection as the driving force of all evolutionary
change; the creative mechanism which adapted and
diversified all life. However, natural selection was not
a new concept, and decades prior to Darwin’s theories, creationists like Edward
Blyth had ably demonstrated the reality of natural selection. While the mechanism
itself was well understood, what it was able to achieve was somewhat more
speculative, and while Blyth considered it to be a preserving force to maintain
species, Darwin thought it was a creative force which changed species, and
moreover, this change was without limit.
At this stage, uniformitarianism was a popular idea in geology – that many small changes over a very long
time had brought about current geological features. Darwin imagined that natural selection had operated in
the same way, bringing about the present diversity of life from a single common ancestor. While this sort of
extrapolation backwards (or forwards) in time is a valid way of developing scientific hypotheses – that is,
using the logical principle of inductive
inference to make generalisations from
specific data – it is only as valid as the
assumptions upon which it rests. In this
case, Darwin’s assumptions were
threefold:
(1) The mechanism of change in the
present (i.e. natural selection) was
the same mechanism operating
throughout all evolutionary time,
(2) Life had been evolving for millions
of years, and
(3) It was necessary to explain the
existence and diversity of life
through natural processes alone.
Figure 1. Charles Darwin described the role of Natural Selection on speciation in his famous 1859 book, On the Origin of Species.
Figure 2. Creationist Edward Blyth described Natural Selection in a series of scientific papers 1835-1837.
Figure 3. Darwin's evolutionary hypothesis rested on a number of key assumptions, ultimately based upon unverifiable ideology.
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In order for his general theory of evolution to hold, all three assumptions
would need to hold. Digging deeper, all three were ultimately based upon the
ideological presupposition of Philosophical Naturalism (the belief that only the
natural exists; nothing supernatural), and so evolution involves an element of
faith in worldly philosophy which most Christians rightly oppose (Figure 3).
Philosophical considerations aside, however, a modern understanding of genetics
refutes this first assumption, as shall be demonstrated.
Augustinian friar Gregor Mendel is considered the “father of modern genetics”
for discovering the laws of genetic inheritance. Although his work was largely
ignored and forgotten in his lifetime, it was rediscovered in the 20th century and
combined with natural selection to form the “modern synthesis” of speciation.
The Genetics of Natural Selection: Wolf Example
While most genes are identical between members of the same species (in this case, wolves), some vary,
and these alternative genes are referred to as alleles. If each varying gene could be represented by the
number of a playing card, then each allele would be the alternative suits or colours which that number could
have. If we consider five genes in particular (Ace, 2, 3, 4, 5), and suppose that each gene has two possible
alleles (black or red), then although every wolf will possess each of the numbers in their “hand” of five cards,
the colours will differ from wolf to wolf. Whenever two wolves mate, then the hand of each offspring are
sampled from the hands of both parents shuffled together (Figure 5).
Let’s assume that those five genes are
involved with hair length in wolves, and in
particular, that the “red” alleles are for
short hair, and the “black” alleles are for
long hair. The more red cards a wolf has in
its hand of cards, the shorter its hair will
be; the more black cards a wolf has in its
hand, the longer its hair will be. If most
wolves originally had a good mixture of
black and red cards, then they’d have
medium-length hair on average.
Let’s say we want to put the original wolf population into one of two very different environments – either
a cold arctic environment, or a hot desert environment (Figure 6). In the arctic environment, let’s say that
only wolves with 3 or more black alleles can survive the cold and reproduce, and similarly let’s say that in the
desert environment, only wolves with 3 or more red alleles can survive the heat and reproduce.
Figure 4. Gregor Mendel published the laws of genetic inheritance in 1865.
Figure 6. Placing the wolf population into a different environment where a certain hair-length is favoured will mean that only individuals with favourable genetics will survive and reproduce.
Figure 5. For each of five different genes, the "hand" of any wolf will have either a red or black allele. In this diagram, the offspring of these two wolves could have any allele from either parent, but here the 2nd allele must be black and the 3rd allele must be red.
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After a single generation in the arctic, wolves with too
many red cards will be “selected against” by natural
selection, leaving a population with a higher frequency
of black alleles (Figure 7). If we let those wolves continue
breeding for many generations, the frequency of red
alleles would become less and less. In fact, by chance
some red alleles may disappear completely from the
population, so for some particular genes, only the black
allele remains (Figure 8). When this happens it’s called
“fixation” – one allele has become fixed through the
entire population, and the alternative allele has been
lost. After many generations we might end up with a
breed of long-haired dogs which have many of their hair-
length genes fixed at the black allele. We might see a
similar story for the wolves which we put in the desert;
a breed of short-haired dogs with many red alleles fixed.
Now what would happen if we put those hairy
dogs in the desert, or put the short-haired dogs in
the arctic, and let them breed for many
generations? Over time, would the hairy breed of
dogs begin to look like their short-haired cousins,
or vice versa? Would either breed even begin to
look like the original medium-haired wolf?
Because of fixation, neither breed can return
to the original wolf kind with its full variety of
alleles, and they certainly can’t go further and
develop into the ideal short- or long-haired
breeds (Figure 9). Fixation means that natural
selection is a one-way street in which genetic
variation is only lost and never gained. Figure 9. Natural Selection is a one-way street. Here, the "hands" of the wolf population can be shuffled and “hands” of the two dog breeds can be drawn, but not vice versa.
Figure 7. After one generation in the arctic environment, some offspring have been selected against (not having >2 black alleles). The remaining individuals will have a higher frequency of black alleles, and will start to look hairier on average than their parents.
Figure 8. After many generations in the arctic environment, some genes have become “fixed” with the black allele (genes 2, 3 & 5 here).
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When we consider the family tree of all dog breeds from an original wolf-like ancestor (Figure 10), we see
what general evolution expects to see: a single species diversifying into a huge array of different sub-species,
each with different physical characteristics (phenotypes). However, when we consider what’s occurring
behind the scenes at the genetic level, we know that each of those breeds has lost a lot of genetic variation
due to fixation. Phenotypic variation has increased, but genetic variation has decreased, which is the opposite
of what evolution requires in the long-run.
Natural selection is therefore not evolution on a small scale (i.e. they are not quantitatively different), and
it should therefore not be referred to as “micro-evolution”. Rather, natural selection goes in the opposite
direction and is a completely different type of thing to evolution (i.e. they are qualitatively different).
Darwin’s first assumption that natural selection was an adequate mechanism to explain large-scale evolution
simply doesn’t hold.
Mutations to the Rescue?
Of course, modern evolutionists do not appeal to
natural selection alone, but also appeal to random
mutations as the source of genetic variation. Mutations
do occur, and they do indeed increase genetic variation,
but it is not the sort of variation which evolution requires,
because it does not create new information. Rather,
mutations are like static on a radio transmission; they’re
adding extra sound, but it isn’t of any use; it’s just
random noise. Worse still, it deteriorates the existing
signal!
This unfortunate reality has been and continues to be
consistently demonstrated in all scientific studies into
Figure 10. The “evolutionary tree” of dogs shows an increasing variety of breeds with their own characteristics (phenotypes), but by natural (and artificial) selection, genetic variety is decreasing due to fixation. Evolution requires an increase in genetic variation.
Figure 11. Mutations just add "noise" to the DNA signal.
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random mutations. The unifying characteristic of these mutations is that they
all involve loss, and this loss generally falls into three different categories:
(1) Loss of feature/function. Something is completely removed or disabled.
(2) Loss of efficiency. Something remains in operation, but is less effective.
(3) Loss of regulation. Something which would usually be controlled to
operate only in certain circumstances is now operating much more or
less than it should.
There is another class of mutations which are non-random, such as those
involved in the creation of antibodies by the immune system. These
mutations are highly controlled to deliver specific outcomes, much like a
computer program might use a random number generator (RNG) to perform
a specific role in the software. And in the same way that a RNG cannot create
its own software, neither can non-random mutations generate the genetic
information that evolution requires.
There is not yet a single example of a mutation which can provide the sort
of increase in genetic variation which general evolution requires. All the while,
natural selection continues to drain the pool of genetic variation, constantly
losing the very sorts of alleles which evolution would need to generate!
Valid Inference
In order for a scientific hypothesis to
graduate into an established theory, there are
several key things it has to achieve. The most
basic requirement is that its inductive
inference must be valid, that is, that empirical
(measurable) data sufficiently and consistently
supports the hypothesis. According to Darwin,
natural selection (a process which could be
measured) was sufficient to cause all
evolutionary change from a common ancestor.
However, Mendelian inheritance means
that genes are discrete units (like single playing
cards), and so genetic information can be lost
by fixation, as our wolf example showed. So the
visible increase in phenotypic diversity we can
measure in dogs, Galapagos finches, and other
kinds of organisms actually goes hand-in-hand
with a decrease in genetic diversity. Therefore
natural selection is not a sufficient mechanism
for all evolutionary change as Darwin assumed;
the inductive inference is invalid, and Darwin’s
hypothesis is falsified (Figure 13).
Figure 12. Mutations must increase genetic information at a faster rate than it's being lost, yet no mutations can create the sort of information that’s needed.
Figure 13. Given current scientific data (i.e. selection and mutations), we can infer a creationist hypothesis. However, if the data can’t (yet) be used for inference, then an evolutionary hypothesis is invalid, and so evolutionists are caught between a rock and a hard place.
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However, the evolutionary hypothesis has not been abandoned, but an auxiliary hypothesis has been
introduced to prop up Darwin’s idea, that is, that mutations are a sufficient source of genetic information.
Now random mutations must be shown to generate novel genetic information, not just deteriorating noise,
if they are to qualify as a sufficient mechanism. However, no information-creating mutations have yet been
observed in scientific studies, and so there is still nothing to extrapolate from.
A Creationist Perspective
On the other hand, things are looking increasingly positive for a creationist position. With the “modern
synthesis” of speciation and modern studies on mutations, creationists are in a strong position to validly infer
a creationist hypothesis (Figure 13).
The decrease in genetic information
associated with speciation means that we can
extrapolate backwards in time to organisms with
very high genetic variation. Naturally, there will
be a limit to how much information can be
contained within a genome, and so there will be a
natural limit to how far back an organism’s family
tree can go (Figure 14). This fits very nicely with
the biblical record of “created kinds”.
The universal testimony of scientific studies to
the degrading, information-losing effects of
mutations also means that we can extrapolate
backwards in time to organisms having high-quality genomes with much higher functionality, efficiency, and
regulatory control. Due to mutation rates being unexplainably high (at least to evolutionists), the
extrapolation must actually go back only to recent history. Again, this fits well with the biblical record, and
with the effects of the biblical Fall in particular.
Conclusions
Much of what both the general public and the scientific community consider to be examples of evolution
are simply examples of natural selection, and nothing more. These perspectives have not caught up with the
historical merger of Mendelian genetics with speciation – the “modern synthesis” – in which natural selection
works to reduce genetic diversity, not increase it.
With the process of natural selection now being qualitatively different from large-scale evolution, rather
than quantitatively different, the scientific method of inductive inference which Darwin employed to derive
his evolutionary hypothesis from observational data can no longer be validly applied. In addition to the
wealth of studies into random mutations failing to provide a single case of novel information which is
necessary for large-scale evolution, the theory is not only without philosophical basis as it was in Darwin’s
day, but is also without scientific basis nowadays.
Modern data is increasingly friendly to a creationist perspective. Valid inductive inference leads us to a
hypothesis of recent ancestral kinds with high genetic diversity and highly functional and robust genomes,
which aligns with the biblical record of creation and the Fall.
Figure 14. Speciation is better represented by (a) the “creationist orchard” than by (b) the “evolutionary tree”, because increasing genetic information backwards in time will reach a natural limit.
(a)
(b)
time
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Key Points:
The Theory of Natural Selection was developed and described by scientists like creationist Edward Blyth,
decades prior to Darwin’s theories.
Natural selection has therefore always been compatible with creationism.
Darwin’s evolutionary hypothesis rested on a number of assumptions, both scientific and philosophical.
Scientifically, he assumed natural selection to be a mechanism of limitless diversification.
Philosophically, he assumed that only natural mechanisms were allowed to explain life.
Modern genetics reveals that natural selection reduces genetic variation, not increases it as Darwin had
imagined.
Increases in phenotypic (physical) diversity are associated with decreases in genetic diversity.
Natural selection works in the opposite direction to evolution.
Natural selection alone is sufficient to describe the vast majority of speciation we observe nowadays,
such as the family trees of dogs, finches, etc.
It is erroneous to refer to such family trees as “evolutionary trees” or “micro-evolution”.
Mutations increase genetic variation, but it is noise, not information.
Phenotypic change resulting from mutation always involves loss.
Neither natural selection nor random mutations have ever been observed to generate novel genetic
information.
There is no data to support an evolutionary hypothesis via the scientific method of inductive
inference. Therefore evolution is without a scientific basis.
Instead, the data supports a creationist hypothesis of created kinds with high genetic diversity, and
rapid genetic decay due to the Fall.
Session: 3B (Saturday 5th 11am)
Topic: Genetics / Evolution vs. Natural Selection
Speaker: Matthew Price
Creation & Apologetics Camp, 4-6th August 2017
Karakariki Christian Camp (KCC), Waikato, NZ
Organised by FoCMI Hamilton (Friends of Creation Ministries International)
Email: [email protected]