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HOW DO CHANGES IN ORGANISMS
OCCUR?
The root source of differences between any two
organisms is found in their DNA. SomeDNAmay be the
same because the bodies of the organisms must perform
similar tasks, but there are many, many differences.
DNA is a repository, much like a library, that encodes
information for the organism’s proteins that build,
grow, and maintain that life-form’s physical body. DNA
is composed of four bases: adenine (A), cytosine (C),
guanine (G), and thymine (T), arranged in a specific
sequence. Changes in the sequence of these bases are
known as “mutations” and can come in many forms,
including the deletion, addition, or rearrangement of
bases. For evolution to be true, many mutations would
have had to take place, and the type of mutations would
necessitate the organism’s physical form undergoing
dramatic change over long periods of time.
One of the most popular examples of mutations (and
often touted as “evolution in action”) is the development
of antibiotic-resistant bacteria. Antibiotics are given to
kill bacteria-causing infection and disease. However,
bacteria have developed defenses against antibiotics
over time, enabling them to survive medicines that
would have killed them previously. This is a very
serious concern in the health care field as some bacteria
have become resistant to multiple antibiotics (e.g.,
methicillin-resistant Staphylococcus aureus, or MRSA),
leaving doctors with no arsenal to treat patients.
Bacteria develop resistance through mutations
in their DNA. Some scientists have termed these
“beneficial” mutations. They aren’t saying that it’s
“beneficial” for bacteria to exist that can survive
antibiotic treatment; they’re speaking from a scientific
mindset. With antibiotic resistance, the mutation is
beneficial because it facilitates the organism’s ability
to prevail in spite of the effort to eradicate it. I would
agree with that conclusion to a certain extent. These
mutations are beneficial for bacteria living in an
environment where adapting is advantageous, such as
a hospital or nursing home where antibiotics are used
heavily. However, are these mutations really beneficial
for that organism overall?
Mutations always come at a cost. In this case, the
bacteria gain the ability to resist the antibiotic, but they
have done so while losing or altering their ability to do
something else. For example, Helicobacter pylori, the
bacteria responsible for ulcers, produces a protein (we’ll
call it the N protein for short) that is important for the
bacteria’s metabolism. One of the antibiotics given for
H. pylori infections targets this protein. The N protein
converts the antibiotic into a poison, and the bacteria
die. Sadly, the overuse and abuse of antibiotics in some
countries have led to the development of antibiotic-
resistant H. pylori. These H. pylori have a mutation that
makes them unable to produce the N protein. When
the antibiotic is given to individuals for treatment, the
N protein is not present in the bacteria, so they don’t
convert the antibiotic into a poison and they survive.
The mutation and the subsequent resistance have
come at a cost. The bacteria no longer produce the
N protein that is needed for normal metabolism.
Sometimes other bacterial proteins can perform the
missing function, but usually not as well. The resistant
bacteria survive well in a health care setting (where
there is heavy antibiotic usage) because there is limited
competition (fewer bacteria) for the limited nutrients
in their environment. Outside of that setting, the
resistant bacteria are at a disadvantage because they
cannot perform normal functions as well and can be
outcompeted by bacteria able to make the N protein.
What we learn is that mutations can be beneficial in
certain environments but, overall, it’s really a trade-
off resulting in no overall benefit or net gain for
the bacteria.
The point is this: mutations, instead of being the
missing piece in the evolutionary puzzle, are typically
destructive, or at least not supportive of directional
change, as we see with just this one example (and there
are many more I could share!). This is true for the
vast majority of mutations; they destroy information
encoded in the DNA.
HOW ARE MUTATIONS A PROBLEM
FOR EVOLUTION?
Evolutionists believe that numerous mutations,
accumulated over long periods of time, have led to
the evolution of all life from a single-celled common
ancestor. In order for human life to have evolved from
this ancestor, mutations would have to change the
DNA so the organism would eventually make brains,
eyes, and ears (just to name a few!). But mutations
are destructive, as we’ve seen with antibiotic-resistant
bacteria, and simply cannot make the kinds of changes
evolution requires.
Let’s look at the popular evolutionary idea that
dinosaurs evolved into birds. I once watched an
The point is this: mutations, instead of being the
missing piece in the evolutionary puzzle, are
typically destructive, or at least not supportive
of directional change.
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Cedarville Magazine