Some Common Arguments For Evolution
So far I have presented some arguments against the Theory of Evolution based on
Scientific Laws, the fossil record, the origin of life, mutations, and complexity. Now, I would like to
consider some of the most common arguments used to promote the theory.
The Recapitulation Theory
How many of you have heard the phrase 'ontogeny recapitultes phylogeny'? This expresses the idea that
during gestation, the human embryo undergoes changes which mimic its evolutionary history. This idea was formulated and
published by Ernst Haeckel in the late 1800's. Shortly after its publication, it was revealed that the drawings of the embryos
he used were purposely altered to look similar. Haeckel himself even admitted to the deception years later after being convicted of fraud. But the idea,
none the less, had caught on. Even though it was disproven in the 1920's, the recapitulation theory made its way into many
late 20th century textbooks, sometimes even being refered to as the 'Biogenic Law'. Unfortunately, some of the ideas are still used today. For example, it is sometimes suggested that 'gill slits'
and a 'tail' are present at certain stages of human embryonic development. This, of course, is not true. Actually the supposed
'gill slits' aren't slits at all, but just folds in the skin. And the 'tail' just forms the basis of the coccyx, and develops disproportionately quicker than other parts.
So, although this theory pops up every so often in an argument or the popular media, it really has been dead for a long time.
Vestigial organs are said to be organs which were necessary in the past evolutionary history of an organism, but no longer have a function. In other words they
are useless leftovers. At the turn of the 20th century, there were approximately 180 organs in the human body which were listed as vestigial. Some of the more popular ones making the list were:
Of course, all of these organs have been found to be not only useful, but necessary. And today, all but a few of the original 180 have been crossed off the list. Since then researchers have learned that it is much more advantageous to search for
the function of these than to simply consider them useless.
- pineal gland
Similarites of Structures
Similarities in structures between different species or similar 'homology' has often been cited as a proof of evolution. An example would be the forelimb bones
in man, horses, bats, whales, and dogs. But, just because some things look the same or share the same types of structures doesn't necessarily preconclude that
they share the same ancestors also. It is tempting to look at the hand of man and the hand of an ape, see the similarities and draw that conclusion. But, if we do that, we
must follow the same logic when we see similarities elsewhere also. For instance, the human eye is very similar to the octopus eye, yet they are so far removed from each
other on the supposed evolutionary chain that no one wants to use this as an example of closeness.
Also, now that science has progressed we can determine which genes give
rise to certain structures. When this is studied, it demonstrates that the genes that give rise to some of these similar structures are different. In his book Darwin's Enigma, Luther Sunderland
sums this fact up nicely with a question-
Since evolution is supposed to be a change in the genes which changes the structures that they control,
how could the structures remain virtually unchanged, but the genes that control them become changed completely?16
One might ask 'If these similarities aren't the result of a common ancestor, then why are they there?' Another possible answer is that there is a common designer rather than a common ancestor. As an example
let's look at some paintings:
Some might recognize these as works of Vincent Van Gogh. They are different paintings, but the similarities are obvious enough to determine that they are
the work of the same artist. In much the same way, the similarities in different creatures may exhibit the handiwork of the same Marvelous Creator.
Another often cited and often misunderstood argument is antibiotic resistance. It is true that over the course of time and use, antibiotics become less effective due to resistance gained by the organisms.
Our question is weather this resistance is an example of evolution. Are these bacteria actually mutating into new and better organisms? Let's look at the mechanisms by which resistance develops.
- Inherent Resistance--There are some organisms which have an inherent resistance to some antibiotics. The resistance mechanism is present all along, even before being introduced to an antibiotic. This was demonstrated to be
true by collecting bacteria found in villages where modern antibiotics hadn't been used, and from the frozen intestines of past explorers. These bacteria were challenged with modern antibiotics and some were found to be resistant already.
- Transfer of Resistance--It is possible for genetic information to be transfered between bacteria via rings of DNA called plasmids. Sometimes this shared DNA involves information for resistance, and is thus expressed in the receiving organism.
Remember that no new information is 'created' by the newly resistant bacteria, it is only information which existed already and is merely transfered.
- Resistance Through Mutation--In this type of mechanism, resistance is gained through mutation. But the one thing that these mutations have in common is that they all involve a loss of information. And when not in the presence of the antibiotic, the resistant one may actually be
'weaker' than the rest. The following simplified scenerio will demonstrate this idea.
A group of bacteria function normally when a certain nutrient enters into the cell through a pump in the cell wall. One bacterium in the group has a mutation where this pump does not work well, but is still able to survive. Now suppose that an antibiotic kills these bacteria, but only
when it can get inside the cell through that same nutrient pump. When this antibiotic is introduced to the group, they are all killed--expect the one with the faulty pump. This one then survives and replicates, eventually resulting in a group of resistant bacteria.
Notice again that no new informatin was added, and it is actually a weaker, degenerative strain, compared to the original group. This mutation may indeed be beneficial in that circumstance, but it certainly does not produce a better and more complex organism as the theory of evolution demands.
Probably the most popular argument for evolution is the peppered moth (Biston betularia). It has been used to demonstrate the idea of natural selection in relation to evolution. Let's take a closer look at this and see what it really demonstrates.
Before the industrial revolution, the forests in Great Britain were mostly made up of light colored trees. At this time, the peppered moth existed in both light and dark colors, but the population was predominantly white. The pollution which resulted from all the new factories eventually
turned the bark of the trees dark, and with this, there was a population shift and the dark colored moths became the majority. This occurred because the light colored ones lost the natural camouflage of the light trees and were thus more easily spotted by birds. Since then, Clean Air acts have been
passed, and again a shift occured, increasing the population of the light colored moths. It is true that this demonstrates how natural selection works, but it doesn't speak a word about evolution. What started as a peppered moth, existing in both light and dark colors, remains a peppered moth in both
light and dark colors. Where is the evolution? Where is the emergence of a new and better species? What this observation actually demonstrates is that even through altered environments, a moth will always continue to be a moth.
If you have been to any natural history museums, the above display should be familiar to you. It is the standard account given for the evolutionary path of the modern day horse. As with other 'examples of evolution', it certainly does look convincing. The tale goes like this:
Our modern day horse started out about 60 million years ago as a small, four-toed animal called Eohippus or the "dawn horse" formerly known as Hyracotherium. From there it grew in size, lost a toe and was known as the Mesohippus. The larger, Merychippus then came on the scene, followed by the one-toed Pliohippus.
This then was replaced by Equus, our modern day horse.
This seems like a neat, easy to see progression, but let's look at some lesser known facts. To start out with, some paleontologists argue that Eohippus isn't related to the horse at all. It is actually more similar to our modern day hyrax, which accounts for its original classification as Hyracotherium.
Also there is nowhere in the world, except museum displays, where this series is found in successive strata. Actually, the one-toed creatures are found alongside and even BELOW the three-toed type in the strata. Eohippus fossils have been found with certain species of Equus as well.
But the story doesn't end here. When depicted in displays and textbooks, the toes are often highlighted to suggest a progression. But why don't they discuss things like the ribs. Beginning with Eohippus there are 18 pairs of ribs. This number changes to 19 pairs, then 15, then back to 18 for Equus.
And as with all other supposed lines of ascent, all these creatures are fully formed and fully functional with no partial or transitional forms filling in the gaps to connect them.
Probably the most famous of all fossils, the Archaeopteryx fossil is said to contain the image of a truly transitional creature. Discovered in Germany in the mid 1800's, the species was said to have had characteristics of both reptiles and birds.
It had teeth and claws as some reptiles do and feathers like birds. Having features of both of these types of animals, it was heralded as an example of a reptile on its way to becoming a modern bird. But, as good investigators, we must consider some other things before it gets our stamp of approval.
For instance, let's look at the teeth. Is that really a reptilian feature? Not all reptiles have teeth, some do and some don't. Some fish have teeth and some don't. Some mammals have teeth and some don't. There were even some birds that had teeth. So the fact that it had teeth, doesn't necessarily link it to reptiles. When compared, the teeth on the Archaeopteryx were not even similar to reptilian teeth.
When we consider the claws, again we must realize that we aren't necessarily dealing with an exclusively reptilian feature. There are actually birds living today such as the hoatzin and ostrich which have clawed wings. After years of study, Archaeopteryx has been classified as a bird. It had fully formed feathers, a large wishbone, as well as the brain and jaws of real birds.
So, after all the hype, we see that it was nothing more than a bird with a couple specialized features.
To further solidify the point, let's discuss what it would take for a reptile to change into a bird. First of all it would somehow have to change scales into feathers. The truth is, scales are a far cry from feathers which are very complex and specialized. Scales are actually just folds in the skin. Feathers on the other hand come from follicles inside the skin.
They also possess an intricate structure of tiny hooks and barbs making them strong and waterproof. They are also lightweight with the correct aerodynamics for flight. Some other differences between reptiles and birds that would have to change are:
Again, there is no evidence whatsoever in the fossil record of any gradual change in any of these systems or even any conceivable working models of change.
- The repiratory system--reptiles have a billows type where the air enters and exits through the same pathway. Birds have a completely different type which is essential for flight, where the air enters and exits through different pathways.
- The skeletal system--birds have lighter, hollow bones which allow for flight, reptiles don't.
- The digestive and nervous systems of reptiles would also require radical changes.
Ever since the idea that humans evolved from apes became popular, there has been a race to discover the missing link. This link would be a creature caught in a stage between distinctly ape and distinctly human.
Over the years there have been many candidates to fill this role, some popular and promising and others an embarassment to those embracing them. Let's look at some of these characters.
There are also some stories which would make the 'best-if-forgotten' list...
- Ramapithecus--A few jaw fragments and several teeth were found in Africa in the 1930's by Dr. Pilbeam. The jaw seemed to be ape-like with human characteristics and therefore the creature was
classified as a possible human ancestor. A complete jaw and skull portion was later found and Ramapithecus is now known to have been an extinct type of orangutan.
- Pithecanthropus or 'Java Man' came on the scene in 1891 when a tooth, skullcap and thighbone were unearthed by Eugene Dubois. The tooth and skullcap were considered to be ape-like and the femur looked human. Dubois summized that they were from an
upright-walking ape or an intermediate between ape and man. The problem was that the skullcap and thighbone were found 50 feet apart making it suspect weather they were even from the same creature. After some of his peers failed to comfirm
the findings, Dubois later admitted that the skullcap was nothing more than the ramains of a giant gibbon.
- Zinjanthropus or 'Nutcracker Man' was discovered by the famous Leakey team in 1959. They were working at the Olduvai Gorge in East Africa, and found a skull with a large jaw and teeth. Thus the knickname "Nutcracker Man". They also found some
chipped stones which they assumed were made by Zinjanthropus and used as simple tools. Upon further excavation of the site, human remains were found in the same layer and the layer just above where the original creature was found. Since then, the tool-making has
been attributed to the humans that were found, and Zinjanthropus has been
reclassified as an Australopithecine (a type of ape), which is what Louis Leakey originally thought it was before the tools were found.
- Sinanthropus or 'Peking Man'--In 1927 Davidson Black suggested the idea of "Peking Man" after examining a fossil tooth from a mine in Choukoutien, China. He then enlisted Dr. W. C. Pei to direct an excavation of the site, where many ape-like fossils were found.
There were skulls, skullcaps, jaws, and teeth, as well as an ash pit which is an indication of human activity. So it seemed as though these non-human creatures were capable of human activity and thus on their way to becoming modern man. But, when one looks at everything
that was found, a different story unfolds. Mixed together with the ape-like skulls, were many other fossils also. These included remains of deer, elephants, rhinoceros, bears, hyenas, cats, rodents, a horse, a buffalo, and a wolf.
Also, the Sinanthropus skulls were all smashed up, with some having holes purposely drilled in them. So it seems more likely that 'Peking Man' was simply another meal for true man along with the other animals found. This scenerio is even more believable when when we
consider that monkey brains are a source of food and the fossil skulls were broken in a way that is consistent with this practice.
- Homo sapiens neanderthalensis or 'Neanderthal Man' may be the most familiar candidate that was once considered a missing link. The Original specimen was discovered in 1848 at Forbes Quarry on Gibraltar. But it wasn't until a find in the Neander Valley in Germany in 1856,
that Neanderthal Man became popular and thus got his name. Since then there have been a great number unearthed, some as complete skeletons, in different places in Europe and the Middle East. The Neanderthal fossils looked essentially human, but with certain unusual characteristics that stood out.
He wasn't as tall as modern man, had thicker bones, and a flatter skull with distinct brow ridges. Because of these traits, Neanderthal Man has been pictured as somewhat of a brute, far less intelligent or as sensative as modern man. But, as research continued, it was found that Neanderthals
suffered from certain diseases such as arthritis and rickets which explained his bone deformities. In fact, this idea was first suggested by Rudolf Virchow "the father of pathology" when he examined the first Neanderthal skullcap.
Also, the Neanderthals were not the unintelligent, insensative brutes that their reputation suggests. It has been discovered that they:
Recent research has suggested that the DNA of Neanderthals differs too much from modern humans to be an ancestor, and therefore could be an offshoot from some earlier common species. But the difference in the DNA between Neanderthal and modern man is actually within the limits of difference in modern man alone.
So when all is said and done, the evidence suggests that Neanderthal Man was a true man with the unfortunate predicament of living in a hostile environment making him susceptible to certain deforming diseases.
- lived in huts sometimes located in caves
- wore clothes
- cooked their food on fires
- ceremonially buried their dead
- grew flowers
- painted pictures
- made musical instruments
- Australopithecus afarensis AKA 'Lucy' was discovered by Donald Johansen in 1974 in Ethiopia. The creature was only 3 & 1/2 feet tall with distinctly ape-like features. The one thing that differentiated it was that it had a pelvis and angled femur which may indicate that it walked upright. Therefore, the
find was promoted as an upright walking ape-like creature and the oldest known ancestor of man. But further study has shown that its features are consistent with simple tree-dwelling apes whose gait would have been much more similar to a pygmy chimpanzee than a human. Therefore, 'Lucy' is no longer considered in
the line of humans by most paleontologists.
Of course, there have been many more candidates besides these, but there are no universally accepted or unchallenged specimens that can be considered human ancestors. All are either true humans or true apes, no in-betweens. One might ask why there have been so many promoted as such or how so many scientists are so
easily fooled. The answer goes back to the field goal at the beginning of our discussion. If someone believes that evolution is true, this belief is reinforced in school and in the media, and the object of their chosen profession is to discover the missing link, then it should be no suprise to us when they think that they
have found one. By the way, after 150 years of research, there is still only one thing that we know for sure about the 'missing link', do you know what it is?
- Hesperopithecus known also as 'Nebraska Man' was imaginatively created by Henry Fairfield Osborn based on a single tooth which was found
in Nebraska in 1922. From this one tooth and a description by Osborn, the Illustrated London News published an article and drawing of Nebraska Man complete
with his family and their home surroundings. 'Nebraska Man' was even discussed as evidence for evolution at the famous Scopes Monkey Trial. Eventually the true owner of the tooth was discovered and it was not a human, an ape, or anything in between. Actually it turned out to be nothing other than an extinct pig.
Eoanthropus also known as 'Piltdown Man' was promoted by Charles Dawson, Arthur Smith Woodward, and Pierre Teilhard de Chardin to be the earliest Englishman. Between 1908 and 1915 some fossils were 'discovered' in a gravel pit in Piltdown, England. Among the finds were a human looking skullcap
which was associated with an ape-like jaw. The find was named 'Piltdown Man' and although there were a few skeptics, it was considered an ape-like human ancestor for the next 40 years. During this time it made its way into classrooms, museums, textboks, and encyclopedias as a missing link. In 1953 it was finally
discovered to be a complete hoax. The skull had been purposely broken and stained.The jaw and teeth were altered as well by being filed down. To this day there is some question as to the identity of all the culprits, and 'Piltdown Man' has gone down in history as the greatest (or worst) hoax ever perpetrated on the
to find out the answer.