Following the Ham/Nye
debate, a disturbing post went around on Facebook showing over 20 creationists
trying to make a point against naturalism or evolution by holding up a sign
with a clever statement or question on it that was supposed to make skeptics
doubt their worldview. I know from
conversations with people who know science that it actually did the opposite. When
arguing against a scientific theory or model, it is best to learn about the
subject first! Any argument against
evolution that has a chance to be successful must either present evidence
against the model or show how the current evidence is being
misinterpreted. The more we labor to
understand the science and then actually address the real issues, the further
we get with the scientific community. Conversely, little is accomplished when
one attempts to argue from an uninformed position.
Naïve statements actually drive people away from Christianity
and perpetuate the idea that Christians are not intellectuals. We need to stop
putting up barriers that keep people from even listening to the gospel; making sophomoric
statements about science perpetuates the myth that Christianity is only for the
uneducated. Since evolution is the hot topic and the one to which most people
direct their statements, here is a quick primer to help us understand the
theory better so we can discuss evolution from an intellectually informed
position.
The broadest meaning of evolution is simply “change over time.” But
evolution has many other meanings
embedded within it, so we must be careful to be specific about our terms. I
like how Fazale Rana of Reasons to
Believe[1]
breaks down the word evolution, so I am borrowing many of his definitions. One
of the most common types of changes being referenced by the term evolution is “microevolution.” This is the
variation that happens within a species in response to changes in environment,
changes in competitive and predatory pressures, or genetic drift. This allows a species to adapt to its
environment and has been directly observed, so there is no reason to argue
against this definition. Species are
adapting to their environment when the peppered moth population in England
changes to a darker color because of pollution, when the finch beaks in the
Galapagos become thicker during the dry season, or when guppy populations
change from bright colorings to mostly grey, due to increased predation.
“Speciation” is the next
meaning buried within the term evolution.
Speciation comes from long term microevolution due to population isolation; a single
population branching into a closely related organism, different enough to be
classified as a different species. This has been directly observed, so this
should not be argued either. For example, a turtle population can develop longer
necks because of their isolation on an island, separate from other turtles. This change is enough to make them a
different species.
Another definition
buried in the term evolution is “microbial
evolution.” This is a form of micro-evolution, but occurs when viruses,
bacteria, and single celled organisms change due to some kind of environmental
pressure like pesticides or antibiotics.
This has also been directly observed. Ironically, this type of evolution
may actually be evidence against macro-evolution!
We have directly observed the HIV virus, the malaria organism, and E. coli
bacteria evolve through countless generations, greatly surpassing the numbers
of mammals that have ever lived in the earth.
What this has shown us is that there might be limit to what natural
selection can do!
The bottom line: Despite huge population numbers and intense
selective pressure, microbes as disparate as malaria and HIV yield similar,
minor, evolutionary responses. Darwinists have loudly celebrated studies of
finch beaks, showing modest changes in the shapes and sizes of beaks over time,
as the finches’ food supplies changed. But here we have genetic studies over
thousands upon thousands of generations, of trillions upon trillions of organisms,
and little of biochemical significance to show for it.[2]
“Natural Selection” is
also a concept embedded in the term evolution.
This is the process through which evolution occurs. Some individuals in a population may have one
or more characteristics that allow them to reproduce at a higher rate than
other individuals in that population.
This results in that particular set of characteristics being more
prevalent in the population and is why populations of organisms can adapt to
new environments. If a population gets
isolated by some geographic barrier, then natural selection operating in the
new environment can result in speciation. Charles Darwin was not the first to
propose that existing life on this planet came from previous organisms; what
associated Darwin’s name with evolution was his discovery of evolution’s
mechanism, natural selection.
“Chemical evolution” is
probably the least used meaning of the term evolution.
This has implications in the origin of life; that nature can create life through
chemical processes all on its own. Chemical
evolution assumes that the organizational properties of atoms and molecules can
manifest over long periods of time, resulting in the chemicals necessary for
life. Chemical evolution requires complex organic molecules to form from simpler
inorganic ones. This has not been
observed under totally naturalistic circumstances, but instead when the
building blocks for life have been shown to organize into materials needed for
life it has been under very controlled conditions in a laboratory; not in the
very dilute, very destructive, and very random conditions on the early earth.
The experiments which create the substances necessary for life actually are
showing that an outside mind is necessary to control the conditions for this to
happen.
…when scientists do laboratory experiments, they are
no longer passive observers of undirected processes. Instead, these researchers
become active participants,
1.
Designing the
protocol;
2.
Assembling the
apparatus;
3.
Supplying the
media and reagents for the experiments;
4.
Adjusting the
initial conditions and regulating them throughout the study;
5.
Monitoring the
course of chemical and physical changes, usually by withdrawing material from
the apparatus.
In other words, human beings interject themselves into
the experiment’s design, ironically, to demonstrate that life can emerge all on
its own without purposeful intervention.
[These experiments are] no longer reflecting the actual evolutionary
events thought to have occurred on the early Earth. Instead, these efforts
reflect what’s possible when a researcher – an intelligent agent – orchestrates
physiochemical processes.[3]
When most people think
of the term evolution, I believe they
are thinking of a population of organisms evolving into another entirely new
creature, which we can call “macroevolution.” This is an extrapolation of micro-evolution
and speciation. You can imagine if an
organism continued to change over long periods of time it could evolve into a
totally new type; like some ancient pig-like populations of anthracotheres adapting and
changing through a series of new types of organisms eventually into hippopotamus
and whales. Along with chemical evolution, this is the type of evolution that has not been directly observed. It is
inferred as the best explanation from extrapolating speciation events, for what
we see in the fossil record, from the biogeography of life on this planet, from
homology (similar structures in different types if animals), and from DNA
sequences. Since we have been able to sequence DNA, we have noticed that the
more similar the sequence of genes, the more closely related the species are in
history.
There really is no other
competing naturalistic, scientific theory to explain the history of life on
Earth; not because of some conspiracy, but because the evidence doesn’t yet
warrant it! Scientists make their name by overturning existing theories and
paradigms, so if there was another valid theory, someone would be presenting
the counter evidence and arguing for it!
Because of recent evidence, a part of the theory is in flux. The actual genetic mechanism of natural
selection is in question; moving to a focus on developmental and regulatory
genes as the places where the changes originate and away from the old idea of
point mutations on the protein coding regions causing the changes.
Even though there is no good
competing scientific theory, there are good reasons to be skeptical of what I
have defined here as chemical evolution and macroevolution, as well as the
extrapolation of microevolution. I will address both good arguments and bad
arguments against evolution in future posts. What we cannot do is argue from a
naive position or try to argue against science by using the Bible. If we want people to both respect us and listen
to us, we must know what we are talking about and we must limit our arguments
against science to the evidence from the natural world. If Christianity is true, then what we find
will not conflict with what the Bible teaches; there is no reason to fear
science or use bad arguments. Either of
these mistakes will be doing a disservice to Christianity by driving Bible
believing Christians out of the scientific arena or by turning away seekers
from ever hearing the gospel.
[1] Reasons to Believe, www.reasons.org
[2]
Michael Behe, The Edge of Evolution, 2007, Free Press, New York
[3]
Fazale Rana, Creating Life in the Lab,
2011, Baker Books, Grand Rapids, Michigan
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