This medical image shows the appendix coming from the large intestine. (Click for credit) The appendix is a tube-like structure that extends from the cecum, a small pouch that forms the beginning of the large intestine. In the medical image on the left, you can see it because it is filled with a contrast medium, as is the large intestine. For a long, long time, evolutionists have told us that the appendix is useless. It is a leftover vestige from when our ancestors depended heavily on vegetation for food. We have evolved out of such dietary needs, and as a result, we don’t need an appendix anymore. So the appendix we have today is just a shriveled remnant of what used to be a large, complex cecum in our ancestors. Here is how the Cambridge Advanced Learner’s Dictionary defined the appendix in 2008:1
BODY PART: 1 (plural appendixes) a small tube-shaped part which is joined to the INTESTINES on the right side of the body and has no use in humans
[emphasis in original]
Of course, anyone who has been reading this blog for a while knows what the scientific evidence actually says: The appendix is not useless in any way. As a recent study tells us:2
Substantial evidence supports the view that the cecal appendix is an immune structure primarily functioning as a safe-house for beneficial bacteria, and comes from a range of disciplines, including medicine, epidemiology, immunology, and microbiology.
In order to salvage what they can, most evolutionists who know about the recent evidence now admit that the appendix has function, but they still insist that it is vestigial. They argue that the appendix evolved this new function once the old function was no longer needed.
At least some evolutionists, however, are more interested in what the data actually say. The authors of the study in reference (2) have looked at the data and have come to the conclusion that the appendix is not vestigial in any way. Instead, it is so important that it has evolved independently at least 32 separate times throughout the course of mammalian evolution!
A chromosome-by-chromosome comparison of chimpanzee and human DNA. The chimp DNA was cut into slices of varying lengths (see legend on the right), and a similar sequence was searched for on the relevant human chromosome, which is shown on the horizontal axis.
(Copyright Answers in Genesis, published at http://www.answersingenesis.org/articles/arj/v6/n1/human-chimp-chromosome in a study by Jeffrey P. Tomkins)
I have written about the similarity between human and chimpanzee DNA three times before (here, here, and here). It’s an important question for creationists, intelligent design advocates, and evolutionists alike, since the chimpanzee is supposed to be the closest living relative to human beings. As a result, a comparison of chimp DNA to human DNA gives us some idea of what the process of evolution would have to accomplish to turn a single apelike ancestor into two remarkably different species like chimpanzees and people.
Early on, it was widely thought that human DNA and chimp DNA were 99% similar. As I discussed in my first post on this subject, that was based on a very limited analysis of only a minute fraction of human and chimp DNA. Now that the entire set of nuclear DNA (collectively called the “genome”) of both humans and chimpanzees have been sequenced, we now know that the 99% number is just plain wrong. Interestingly enough, however, even though both genomes have been fully sequenced with a reasonable amount of accuracy, no one can agree on exactly how similar the two genomes are.
Why is that? Because comparing genomes is a lot harder than you might think. While we know the sequence of the chimp and human genomes really well, we don’t understand the DNA itself. Indeed, there are large sections of DNA that seem to be functional, but we simply have no idea what they do. As a result, comparing the genomes of two different species can be very, very tricky.
Horizontal Gene Transfer (represented by the arrows and paths connecting the different lineages in the drawing) is a convenient way for evolutionists to explain around the fact that the data falsify their predictions. (Click for credit)
When I was a young, impressionable student at university, I was taught as fact that all organisms on this planet could be arranged in a hypothetical “tree of life” that showed how all of them evolved from a single, common ancestor. It didn’t matter that no such tree had actually been constructed. I was told that in time, we would be able to sequence DNA quickly and efficiently, and once that happened, the tree of life would emerge from the data in all its glory. However, once DNA analysis did become reasonably quick and efficient, the tree of life never emerged. Instead, the supposed evolutionary relationships that had been determined from the fossil record were contradicted by those that were determined from the genes. Worse yet, the genetic story of evolution changed depending on which specific genes were studied.
This was especially apparent in the analysis of single-celled organisms. As more and more genetic analyses were done on such organisms, it became increasingly obvious that there was simply no way to arrange their genetic information into any pattern that even remotely resembled a hypothetical tree of life. Some scientists understood what this meant: there is something seriously wrong with the evolutionary framework to which biologists have been clinging. As a result, they have started investigating other, more promising paradigms such as creationism or intelligent design. However, most biologists continue to cling to a view that has been falsified again and again by various data. As a result, they had to find a “way out.” They had to find some means by which they could explain around the fact that the genetic data falsified the tree of life.
Enter the concept of Horizontal Gene Transfer, also known as lateral gene transfer. In this process, a section of DNA is transferred from the genome of one organism to the genome of another, unrelated organism. In other words, rather than passing down a gene through the process of reproduction, horizontal gene transfer allows a gene to travel horizontally between unrelated organisms.
Now the phenomenon itself was known long before the problem with the tree of life had been documented. Way back in 1960, for example, Japanese scientists determined that an antibiotic-resistant bacterium could transfer its resistance to an unrelated bacterium that was not resistant to the antibiotic.1 In time, the mechanism was fully worked out, and it was demonstrated that bacteria could, indeed, swap genes back and forth. As it became increasingly clear that this was a common phenomenon among bacteria, it was recognized that horizontal gene transfer could “smear out” the tree of life for single-celled organisms.2
Since horizontal gene transfer was so successful at explaining away the failed evolutionary prediction of the tree of life when it came to single-celled organisms, it’s not surprising that this same “way out” is now being used to explain why certain genes in animals do not fit the pattern predicted by the evolutionary hypothesis.
A commenter tried to claim that the Ediacaran fossil assemblages offer an explanation around the Cambrian Explosion, but had he actually read the link that was provided, he would have known that they do not. Instead, the Ediacaran fossils cannot be connected in any reasonable way to the fossils found in the Cambrian. To emphasize this, I quoted from N.S. Sharma’s book, Continuity and Evolution of Animals:1
Although the stratigraphic distribution of Ediacaran fossils is clear enough, their biological interpretation remains controversial, providing what amounts to a Rorschach test. Several distinct body plans are represented. Most radially symmetric fossils plausibly represent polypoid organisms or the inflated holdfasts of colonial, dipoblastic animals–mostly unrepresented in the modern fauna. More complex fossils include a range of forms built of repeated, tube-like units. In a stimulating, if controversial proposal, Seilacher grouped such fossils into a clade that he christened the Vendobionta and viewed as an extinct experiment in multicellular organization. Others have questioned that interpretation, assigning various forms to colonial diploblasts or to stem members of several bilaterian clades. It is genuinely difficult to map characters of Ediacaran fossils into the body plans of living invertebrates. Long viewed as the principal problem of interpreting Ediacaran assemblages, this difficulty increasingly appears to be their central point. (emphasis mine)
A paper that was recently published online by the journal Nature demonstrates that Sharma’s characterization of these fossils is right on the money.
A picture of a mineral formation that was widely interpreted as an animal fossil (Click for credit)The Cambrian Explosion presents a serious headache for evolutionists. After all, the fossils found in Cambrian rock are supposed to be about 540 to 485 million years old. However, when you look at the complex animals preserved in such rock, you find every major body plan that exists in today’s animals. Worse yet, when you look in layers that are supposed to be older than Cambrian rock, you don’t find the supposed ancestors of these complex animals. Evolutionists have desperately tried to explain around the problem, but so far none of their explanations work.
In 2004, a ray of hope appeared. The journal Science published an article claiming to have found animal fossils that are 40-55 million years older than the Cambrian fossils. They also seemed simpler than the animal fossils found in Cambrian rock. These simple animals were called Vernanimalcula guizhouena, and the authors thought that they helped to mitigate the evolutionary headaches caused by the Cambrian Explosion. As the authors state in their paper:1
The morphology of Vernanimalcula demonstrates that the evolutionary appearance of developmental programs required to generate a multilayered bilaterian body plan preceded the entrainment of the growth programs required for macroscopic body size. Furthermore, the organization of these fossils, taken together with their provenance, indicates that the genetic tool kit and patter formation mechanisms required for bilaterian development had already evolved by Doushantuo times, long before the Cambrian. Therefore, the diversification of body plans in the Early Cambrian followed from the varied deployment of these mechanisms once conditions permitted, not from their sudden appearance at or just before the Cambrian boundary.
So these fossils showed that the Cambrian Explosion wasn’t an explosion at all. Instead, simpler versions of the complex animals that appear in Cambrian rock existed previously, and the Cambrian era simply represented a rapid diversification of a basic body plan that had already existed in a simpler form.
Of course, like many evolutionary propositions, once this claim was thoroughly analyzed, it was shown to be utterly false.
An artist's rendering of the Mars rover "Curiosity." (NASA image)
A friend of mine told me about a news story he heard on NPR. He said that NASA had some “really exciting” results from the Mars rover named Curiosity, but they were not ready to release the results to the public yet because they wanted to confirm the data. My friend wondered if perhaps NASA had finally found the remains of life on Mars. I found the story on NPR’s website, and it sounds like my friend’s expectation could be right.
According to the story, the principle investigator, Dr. John Grotzinger, says:
This data is gonna be one for the history books. It’s looking really good.
Dr. Grotzinger is waiting to release the results, however, because NASA has been burned a couple of times before. Back in 1996, NASA scientists published a paper that claimed a meteorite from Mars (named ALH84001) held tell-tale signs of bacteria, indicating that there was once life on Mars. As more scientists studied the meteorite, however, several problems with that interpretation were found. As a result, even though some NASA scientists are still saying that the meteorite holds evidence of life on Mars, the data are inconclusive at best.
In addition, NASA scientists published a paper in 2010 claiming to have found a bacterium that could incorporate arsenic into its biochemistry. NASA said that this finding would change the way we think about bacteria and would help us better understand the possibilities for life on other worlds. However, in just a couple of years, two very detailed studies showed that the original NASA claim was incorrect. It’s understandable, then, that NASA scientists are being careful when it comes to the release of any surprising data from the Curiosity rover.
This species of catus worm, Priapulus caudatus, falsified another evolutionary prediction (click for credit)Look at the unassuming worm pictured on the left. It is commonly called a cactus worm, but this particular species is known as Priapulus caudatus. According to evolutionists, cactus worms have been around for at least 500 million years.1, but they just recently falsified yet another prediction made by the hypothesis of evolution. To understand the prediction and why it has failed, you need to learn some background information.
There are many different ways scientists classify animals, but one of the broader ways it is done is by symmetry. Most of the animals with which you are familiar are bilaterally symmetric. This means their bodies can be split into a left half and a right half, and those two halves are roughly mirror images of each other. Cats, dogs, and horses are all bilaterally symmetric, as they all have distinct right and left sides that roughly mirror each other. In addition, cactus worms are bilaterally symmetric. Since there are a lot of animals that have this kind of symmetry, scientists have to find characteristics among the bilaterally symmetric animals that will further classify them.
Well, there are two different ways that bilaterally symmetric animals develop their digestive tract. In all these animals, a puckered indentation forms in the embryo. This indentation, called the blastopore, forms the beginning of a tube that will eventually develop into the digestive tract. However, in some bilaterally symmetric animals, that blastopore ends up becoming the mouth, while in other bilaterally symmetric animals, the blastopore ends up becoming the anus. In other words, some animals start their digestive system with their mouth, while others start their digestive system with their anus. The “mouth first” animals are called protostomes, which is a combination of the Greek word “protos” (which means first) and “stoma” (which means mouth). The “anus first” animals are called deuterostomes, which means “mouth second,” since the Greek word “deuteros” means “second.”
So when a biologist looks at an animal that is bilaterally symmetric, one of the first questions that comes to mind is, “How does the digestive tract develop?” That tells the biologist whether the animal is a protostome or a deuterostome. Well, it turns out that studying the embryonic development of animals is rather time-consuming, so scientists often use other characteristics to infer the group to which an animal belongs. With all that under your belt, you are now ready to learn about the falsified evolutionary prediction.
The La Brea Tar Pits as imagined by Charles R. Knight (public domain image)
Paleontologists have long recognized that the fossil record produces a serious problem for the hypothesis of evolution. Almost thirty years ago, Dr. David Wake and his colleagues stated:1
With natural selection operating in a changing environment as an agent of adaptation, we expect to see changes at the organismal, ultimately physiological and morphological, level. How, though, can we explain the paradoxical situation in which environments change, even dramatically, but organisms do not?
In other words, evolution predicts that in a changing environment, organisms should change in order to adapt. However, when we look at the fossil record, we don’t see such change. Instead, while it is thought that earth’s climate changed dramatically in many different ways throughout the fossil record, the fossils themselves show that the organisms living on earth didn’t change much at all. This has been called the “paradox of stasis,” and while several attempts have been made to resolve the problem2, none of them have been found to be satisfactory.3
In an attempt to understand the paradox of stasis better, Dr. Donald Prothero undertook a series of amazingly detailed studies. With the help of a small army of students, Prothero studied the fossils of all the common birds and mammals that have been preserved in the La Brea tar pits of Los Angeles, California. According to the standard geological view, these tar pits preserved species that lived in the area over a period of time when the region experienced wild climate change. It is thought that 35,000 years ago, the Los Angeles, California area had a very similar climate to what it has today. During the height of the last ice age (20,000 years ago), however, it was significantly colder and significantly wetter. As the ice age waned, the climate returned to what it was 35,000 years ago.
From an evolutionary point of view, one would expect that over the course of this dramatic change in climate, the birds and mammals living in the area would have experienced some amount of evolutionary change in order to adapt to their surroundings. However, that’s not what this series of studies found.
The great orange tip butterfly has a toxin in its wings that is identical to the toxin used by the marble cone snail. (Click for credit)
A former student of mine recently alerted me to a study that was published in the Proceedings of the National Academy of Sciences. The authors were studying the proteins found in the wings of a great orange tip butterfly, Hebomoia glaucippe. As they sorted through what they found, they were surprised to find a toxin known as glacontryphan-M.1 The fact that it is a toxin wasn’t surprising to them. After all, Monarch butterflies have cardiac glycosides in their bodies, which are toxic to many birds.2 It is thought that this is a defense mechanism, because birds that eat a monarch butterfly and get sick are unlikely to eat more monarch butterflies.
Here’s what’s surprising: the toxin is also found in a sea snail known as the marble cone snail, Conus marmoreus.3 You can see how it gets its name:
The marble cone snail (Click for credit)
The marble cone snail uses the toxin for hunting. It injects the toxin into its prey, paralyzing it. That makes the prey very easy to eat. Obviously, the researchers were surprised to find the same toxin in two separate species that are supposed to be distantly related in terms of evolution. More importantly, they were surprised at the fact that the two toxins are chemically identical.
One of the biggest problems facing evolutionists is the explanation of how brand new information can be added to a genome. After all, if flagellates eventually evolved into philosophers, an enormous amount of truly original information had to be added to flagellates’ (and their descendents’) genomes. However, genomes are so well-designed and highly-structured, it is difficult to imagine a naturalistic process that could add information to them. Nevertheless, evolutionists have tried their best. One of the more popular notions is gene duplication followed by mutation. We know that genes can be duplicated. It happens quite frequently. The thought is that when a gene is duplicated, one of the copies can continue to produce the protein it is supposed to produce, while the other copy is free to mutate and find some completely new function.
While the thinking behind this idea is logical, experimental evidence to support it has been hard to find. As a result, evolutionists tend to jump on any experimental finding that might suggest the idea is accurate. This is well illustrated by an article that was linked by a commenter on a previous thread. The article claims that researchers have finally shown how a gene can pick up a brand new function, which can then be amplified and modified over time.
Unfortunately, the article’s claim is not accurate. I had already read the scientific paper on which the article was based1, so when I read the article, I understood how incorrect its claims are. However, I am sure the commenter and many other readers of Science Daily do not. As a result, I want to discuss the study’s actual findings. They are very interesting, and they tell us a lot about the genetics of bacterial adaptation. However, they don’t tell us anything about how genes acquire brand new functions or about how information can be added to a genome.
