Five Major Misconceptions about Evolution
Last update: January 3, 1995
A large part of the reason why Creationist arguments against evolution can sound so persuasive is
because they don't address evolution, but rather argue against a set of misunderstandings that
people are right to consider ludicrous. The Creationists wrongly believe that their understanding of
evolution is what the theory of evolution really says, and declare evolution banished. In fact, they
haven't even addressed the topic of evolution. (The situation isn't helped by poor science education
generally. Even most beginning college biology students don't understand the theory of evolution.)
The five propositions below seem to be the most common misconceptions based on the Creationist
straw-man version of evolution. If you hear anyone making any of them, chances are excellent that
they don't know enough about the real theory of evolution to make informed opinions about it.
Evolution has never been observed.
Evolution violates the 2nd law of thermodynamics.
There are no transitional fossils.
The theory of evolution says that life originated, and evolution proceeds, by random chance.
Evolution is only a theory; it hasn't been proved.
Explanations of why these statements are wrong are given below. They are brief and therefore
somewhat simplified; consult the references at the end for more thorough explanations.
"Evolution has never been observed."
Biologists define evolution as a change in the gene pool of a population over time. One example is
insects developing a resistance to pesticides over the period of a few years. Even most Creationists
recognize that evolution at this level is a fact. What they don't appreciate is that this rate of
evolution is all that is required to produce the diversity of all living things from a common ancestor.
The origin of new species by evolution has also been observed, both in the laboratory and in the
wild. See, for example, (Dobzhansky, T. and O. Pavlovsky. 1971. "Experimentally created incipient
species of Drosophila." Nature. 230:289-292). The "Observed Instances of Speciation" FAQ in the
talk.origins archives gives several additional examples.
Even without these direct observations, it would be wrong to say that evolution hasn't been
observed. Evidence isn't limited to seeing something happen before your eyes. Evolution makes
predictions about what we would expect to see in the fossil record, comparative anatomy, genetic
sequences, geographical distribution of species, etc., and these predictions have been verified many
times over. The number of observations supporting evolution is overwhelming.
What hasn't been observed is one animal abruptly changing into a radically different one, such as a
frog changing into a cow. This is not a problem for evolution because evolution doesn't propose
occurrences even remotely like that. In fact, if we ever observed a frog turn into a cow, it would be
very strong evidence against evolution.
"Evolution violates the 2nd law of
This shows more a misconception about thermodynamics than about evolution. The second law of
thermodynamics says, "No process is possible in which the sole result is the transfer of energy
from a cooler to a hotter body." [Atkins, 1984, _The Second Law_, pg. 25] Now you may be
scratching your head wondering what this has to do with evolution. The confusion arises when the
2nd law is phrased in another equivalent way, "The entropy of a closed system cannot decrease."
Entropy is an indication of unusable energy and often (but not always!) corresponds to intuitive
notions of disorder or randomness. Creationists thus misinterpret the 2nd law to say that things
invariably progress from order to disorder.
However, they neglect the fact that life is not a closed system. The sun provides more than enough
energy to drive things. If a mature tomato plant can have more usable energy than the seed it grew
from, why should anyone expect that the next generation of tomatoes can't have more usable
energy still? Creationists sometimes try to get around this by claiming that the information carried
by living things lets them create order. However, not only is life irrelevant to the 2nd law, but order
from disorder is common in nonliving systems, too. Snowflakes, sand dunes, tornadoes, stalactites,
graded river beds, and lightning are just a few examples of order coming from disorder in nature;
none require an intelligent program to achieve that order. In any nontrivial system with lots of
energy flowing through it, you are almost certain to find order arising somewhere in the system. If
order from disorder is supposed to violate the 2nd law of thermodynamics, why is it ubiquitous in
The thermodynamics argument against evolution displays a misconception about evolution as well
as about thermodynamics, since a clear understanding of how evolution works should reveal major
flaws in the argument. Evolution says that organisms reproduce with only small changes between
generations (after their own kind, so to speak). For example, animals might have appendages which
are longer or shorter, thicker or flatter, lighter or darker than their parents. Occasionally, a change
might be on the order of having four or six fingers instead of five. Once the differences appear, the
theory of evolution calls for differential reproductive success. For example, maybe the animals with
longer appendages survive to have more offspring than short-appendaged ones. All of these
processes can be observed today. They obviously don't violate any physical laws.
"There are no transitional fossils."
A transitional fossil is one that looks like it's from organism intermediate between two lineages,
meaning it has some characteristics of lineage A, some characteristics of lineage B, and probably
some characteristics part way between the two. Transitional fossils can occur between groups of
any taxonomic level, such as between species, between orders, etc. Ideally, the transitional fossil
should be found stratigraphically between the first occurrence of the ancestral lineage and the first
occurrence of the descendent lineage, but evolution also predicts the occurrence of some fossils
with transitional morphology that occur after both lineages. There's nothing in the theory of
evolution which says an intermediate form (or any organism, for that matter) can have only one line
of descendents, or that the intermediate form itself has to go extinct when a line of descendents
To say there are no transitional fossils is simply false. Paleontology has progressed a bit since
_Origin of Species_ was published, uncovering thousands of transitional fossils, by both the
temporally restrictive and the less restrictive definitions. The fossil record is still spotty and always
will be; erosion and the rarity of conditions favorable to fossilization make that inevitable. Also,
transitions may occur in a small population, in a small area, and/or in a relatively short amount of
time; when any of these conditions hold, the chances of finding the transitional fossils goes down.
Still, there are still many instances where excellent sequences of transitional fossils exist. Some
notable examples are the transitions from reptile to mammal, from land animal to early whale, and
from early ape to human. For many more examples, see the transitional fossils FAQ in the
talk.origins archive, and see http://www.geo.ucalgary.ca/~macrae/talk_origins.html for sample
images for some invertebrate groups.
The misconception about the lack of transitional fossils is perpetuated in part by a common way of
thinking about categories. When people think about a category like "dog" or "ant," they often
subconsciously believe that there is a well-defined boundary around the category, or that there is
some eternal ideal form (for philosophers, the Platonic idea) which defines the category. This kind
of thinking leads people to declare that Archaeopteryx is "100% bird," when it is clearly a mix of
bird and reptile features (with more reptile than bird features, in fact). In truth, categories are
man-made and artificial. Nature is not constrained to follow them, and it doesn't.
Some Creationists claim that the hypothesis of punctuated equilibrium was proposed (by Eldredge
and Gould) to explain gaps in the fossil record. Actually, it was proposed to explain the relative
rarity of transitional forms, not their total absence, and to explain why speciation appears to happen
relatively quickly in some cases, gradually in others, and not at all during some periods for some
species. In no way does it deny that transitional sequences exist. In fact, both Gould and Eldredge
are outspoken opponents of Creationism.
"But paleontologists have discovered several superb examples of intermediary forms and sequences,
more than enough to convince any fair-minded skeptic about the reality of life's physical genealogy." -
Stephen Jay Gould, Natural History, May 1994
"The theory of evolution says that life originated,
and evolution proceeds, by random chance."
There is probably no other statement which is a better indication that the arguer doesn't understand
evolution. Chance certainly plays a large part in evolution, but this argument completely ignores the
fundamental role of natural selection, and selection is the very opposite of chance. Chance, in the
form of mutations, provides genetic variation, which is the raw material that natural selection has to
work with. From there, natural selection sorts out certain variations. Those variations which give
greater reproductive success to their possessors (and chance ensures that such beneficial mutations
will be inevitable) are retained, and less successful variations are weeded out. When the
environment changes, or when organisms move to a different environment, different variations are
selected, leading eventually to different species. Harmful mutations usually die out quickly, so they
don't interfere with the process of beneficial mutations accumulating.
Nor is abiogenesis (the origin of the first life) due purely to chance. Atoms and molecules arrange
themselves not purely randomly, but according to their chemical properties. In the case of carbon
atoms especially, this means complex molecules are sure to form spontaneously, and these complex
molecules can influence each other to create even more complex molecules. Once a molecule
forms that is approximately self-replicating, natural selection will guide the formation of ever more
efficient replicators. The first self-replicating object didn't need to be as complex as a modern cell
or even a strand of DNA. Some self-replicating molecules are not really all that complex (as
organic molecules go).
Some people still argue that it is wildly improbable for a given self-replicating molecule to form at a
given point (although they usually don't state the "givens," but leave them implicit in their
calculations). This is true, but there were oceans of molecules working on the problem, and no one
knows how many possible self-replicating molecules could have served as the first one. A
calculation of the odds of abiogenesis is worthless unless it recognizes the immense range of
starting materials that the first replicator might have formed from, the probably innumerable
different forms that the first replicator might have taken, and the fact that much of the construction
of the replicating molecule would have been non-random to start with.
(One should also note that the theory of evolution doesn't depend on how the first life began. The
truth or falsity of any theory of abiogenesis wouldn't affect evolution in the least.)
"Evolution is only a theory; it hasn't been proved."
First, we should clarify what "evolution" means. Like so many other words, it has more than one
meaning. Its strict biological definition is "a change in allele frequencies over time." By that
definition, evolution is an indisputable fact. Creationists seem to associate the word "evolution"
mainly with common descent, the theory that all life arose from one common ancestor. Many
people believe that there is enough evidence to call this a fact, too. However, common descent is
still not the theory of evolution, but just a fraction of it (and a part of several quite different theories
as well). The theory of evolution not only says that life evolved, it also includes mechanisms, like
mutations, natural selection, and genetic drift, which go a long way towards explaining how life
Calling the theory of evolution "only a theory" is, strictly speaking, true, but the idea it tries to
convey is completely wrong. The argument rests on a confusion between what "theory" means in
informal usage and in a scientific context. A theory, in the scientific sense, is "a coherent group of
general propositions used as principles of explanation for a class of phenomena" [Random House
American College Dictionary]. The term does not imply tentativeness or lack of certainty.
Generally speaking, scientific theories differ from scientific laws only in that laws can be expressed
more tersely. Being a theory implies self-consistency, agreement with observations, and usefulness.
(Creationism fails to be a theory mainly because of the last point; it makes few or no specific
claims about what we would expect to find, so it can't be used for anything. When it does make
falsifiable predictions, they prove to be false.)
Lack of proof isn't a weakness, either. On the contrary, claiming infallibility for one's conclusions is
a sign of hubris. Nothing in the real world has ever been rigorously proved, or ever will be. Proof, in
the mathematical sense, is possible only if you have the luxury of defining the universe you're
operating in. In the real world, we must deal with levels of certainty based on observed evidence.
The more and better evidence we have for something, the more certainty we assign to it; when
there is enough evidence, we label the something a fact, even though it still isn't 100% certain.
What evolution has is what any good scientific claim has--evidence, and lots of it. Evolution is
supported by a wide range of observations throughout the fields of genetics, anatomy, ecology,
animal behavior, paleontology, and others. If you wish to challenge the theory of evolution, you must
address that evidence. You must show that the evidence is either wrong or irrelevant or that it fits
another theory better. Of course, to do this, you must know both the theory and the evidence.
These are not the only misconceptions about evolution by any means. Other common
misunderstandings include how geological dating techniques work, implications to morality and
religion, the meaning of "uniformitarianism," and many more. To address all these objections here
would be impossible.
But consider: About a hundred years ago, scientists, who were then mostly creationists, looked at
the world to figure out how God did things. These creationists came to the conclusions of an old
earth and species originating by evolution. Since then, thousands of scientists have been studying
evolution with increasingly more sophisticated tools. Many of these scientists have excellent
understandings of the laws of thermodynamics, how fossil finds are interpreted, etc., and finding a
better alternative to evolution would win them fame and fortune. Sometimes their work has
changed our understanding of significant details of how evolution operates, but the theory of
evolution still has essentially unanimous agreement from the people who work on it.
The "FAQ" files listed below are available on World Wide Web via http://rumba.ics.uci.edu:8080/.
They are also available via ftp at ics.uci.edu, directory /pub/origins. Messages with more
information on how to access them are posted regularly to talk.origins. The archive also contains
many other files which may be of interest.
For what evolution means, how it works, and the evidence for it:
Colby, Chris. faq-intro-to-biology: Introduction to Evolutionary Biology
Mayr, Ernst. 1991. One Long Argument
Darwin, Charles. 1859. On the Origin of Species by Means of Natural Selection
For issues and evidence of speciation:
Boxhorn, Joseph. faq-speciation: Observed Instances of Speciation
Weiner, Jonathan. 1994. The Beak of the Finch: A Story of Evolution in Our Time
For explanations of how randomness can lead to design:
Dawkins, Richard. 1986. The Blind Watchmaker
Bonner, John T. 1988. The Evolution of Complexity by Means of Natural Selection
Kauffman, Stuart A. 1993. The Origins of Order: Self-Organization and Selection in Evolution [very
For a readable introduction to the 2nd law of thermodynamics:
Atkins, Peter W. 1984. The Second Law
For transitional fossils and the fossil record:
Colbert, Edwin H. 1991. Evolution of the Vertebrates, 4th ed.
Hunt, Kathleen. faq-transitional: Transitional Fossils
For a fairly comprehensive response to many Creationist claims:
Strahler, Arthur. 1987. Science and Earth History
Meritt, Jim. faq-meritt: Jim Meritt's general anti-creationism FAQ