Evolution is proven. It is a theory that has withstood
the test of time despite the many obstacles that dishonest and
close-minded creationists have placed in its path. The process of
science is one of peer-review and mutual criticism...a bad theory
does not have much chance at surviving. Scientists endorse
evolution not because of dogma (unlike religious fundamentalists
who stick to their positions despite evidence to the contrary), but
because their findings and research has consistently turned up
evidence supporting evolution.
You want evidence for evolution, here are some of them
taken from:
http://www.talkorigins.org/faqs/evolution-research.html
http://www.talkorigins.org/faqs/comdesc/
And the following is from
(http://www.talkorigins.org/faqs/faq-misconceptions.html)
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 a 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.
Misconception 1: "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, (Weinberg,
J.R., V.R. Starczak, and D. Jorg, 1992, "Evidence for rapid
speciation following a founder event in the laboratory." Evolution
46: 1214-1220). 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.
Misconception 2: "Evolution violates the 2nd law of
thermodynamics."
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 nature?
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.
Misconception 3: "There are no transitional
fossils."
A transitional fossil is one that looks like it's from an 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
evolves.
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
Misconception 4: "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.)
Misconception 5: "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. Most people 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 evolved.
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.
Conclusion
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.
Only someone who has not done consistent and rigorous
scientific reading would claim that evolution is unproven. The
evidences all poitns to it being factual. But creationist
fundamentalists choose to close their eyes and disregard the truth
(which is ironic, considering that their religion claims to be
about finding the truth!)
