Dark DNA and Vestigial Organs: How They Prove the Theory of Evolution

DARK DNA
& VESTIGIAL ORGANS
HOW THEY SUPPORT THE THEORY OF EVOLUTION

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INTRODUCTION
A decade ago, the Human Genome Project gave us a complete list of the 3 billion letters that make up the human genetic code. Back then, we thought we had the book of life. Turns out it was harder to read than we had thought. Really, we only found about 2-3%, or roughly 20 thousand, genes. Scientists started wondering what the rest of this DNA did. They called it the dark matter of the genome, or dark DNA. But now, with the development of the ENCODE project, we can finally shed some light on one of evolution's greatest mysteries.

MISSING GENES
A recent study looked at one case of sand rats, which are prone to type 2 diabetes. When they looked at their genome, the gene Pdx1, which is responsible for insulin production, was undetectable, which puzzled scientists. While deemed needed for survival, scientists found it was missing from the genome of the sand rats. They kept looking and what they found was that Pdx1 was not missing, but obscured somehow, as they found chemical instructions which could only be produced by the gene Pdx1. Not just Pdx1 was “missing” though; around 87 other genes were unable to be detected in their genome.

NOT JUST SAND RATS
Sand rats are not the only animals that have these hidden genes though. Around 274 genes have been shown to be missing from bird’s DNA. Like the sand rat, this too may be from a rapid spike of evolution.

https://youtu.be/LzlUZrt0Ums

GENOME ANATOMY
Scientists then began to look deeper into their DNA, and what they found was that the DNA sequences of the missing genes were very rich in G and C molecules, two of the four base molecules that make up DNA, and that also happen to have mutated so severely that they cause problems for our current DNA sequencing technology. Usually, mutation this severe would cause the gene to shut down and stop working, but somehow the sand rat genes survive. Some scientists believe a sharp evolutionary jump is the cause of the “mutation hotspot.” Instead of genes mutating here and there on their own, several instead mutating together and the genes somehow surviving the extreme mutation. Is this an underlying process behind evolution? Then, there are vestigial genes; extra genes, remnants of ancient predecessors. These have been found in almost every living and extinct creature on earth, and are one of the most important discoveries ever made in evolution.

The question we are answering here is that if the theory of evolution is true, would we predict to find silenced or “dead” pseudogenes that are similar to genes in other animals, but no longer serve a purpose in a certain animal or species? How would we expect these genes to relate to the genes of close and distant species? One of these genes is the gene GLO, which is necessary for Vitamin C synthesis. Vitamin C is essential for proper metabolism and without it mammals get sick and die. Most mammals can self produce it, but fruit bats, guinea pigs, and primates can’t. This is because fruit bats, guinea pigs, and primates get enough Vitamin C in their diet to make the need to synthesize Vitamin C obsolete and “deactivate”. The gene may be present in the genome, but it remains passive and serves no function. Another case of inactive parts in DNA are Endogenous Retroviruses. These are viruses that make copies of their genome and insert them into the DNA of the species they infect. If they infect the cells that produce sperm or eggs they can be passed onto offspring. Most of them are inactive remnants of ancient infections. Very few active retroviruses still are active, such as HIV. Some of these remnants sit in exactly the same location in humans and chimpanzees. Since there is almost no chance of viruses inserting themselves in the same spot in 2 species, this points strongly to common ancestry.

Another case of genes becoming obsolete or less needed are Olfactory Receptor Genes, which allow us to smell around over 10,000 smells. While this seems quite exceptional, it's quite horrible, as we have lost the need to rely on our sense of smell to survive unlike something like a mouse or bear. All of these cases of dark dna and vestigial organs are evidence for evolution, where beneficial heritable traits arise and become obsolete in species over time.

How did we develop all these genes in the first place, or create such a vast ecosystem? How did we evolve from living in the water to living on land or even both? With “Transitional Fossils”, we can see how birds descended from reptiles and how fish evolved into land animals by seeing what came in between dinosaurs and the birds we have today, or how fish somehow grew lungs and muscles that allowed them to survive on land. First, let's look at how we got birds. A dinosaur can't just change their body type to accommodate flying and grow wings, there must be an inbetween. Enter Archaeopteryx lithographica, which has just the combination of traits one would expect to find in a transitional form, and the fossil dates where we would expect; ancient primal wings, feathers, birdlike shape, reptile head with teeth, and a tail.

Let’s take a look at how fish evolved into all the land animals we have today. First, we have to think about what an animal in between a fish and a land animal would look like. In the book Why Evolution Is True, the transitional creature Tiktaalik was the perfect in between “with gills, scales, and fins, it was clearly a fish that lived its life in water. But it also has amphibian-like features. For one thing, its head is flattened like that of a salamander, with the eyes and nostrils on top rather than on the sides of the skull. This suggests that it lived in shallow water and could peer, and probably breathe, above the surface. The fins had become more robust, allowing the animal to flex itself upward to help survey its surroundings. And, like the early amphibians, Tiktaalik has a neck. Fish don’t have necks—their skull joins directly to their shoulders. Most importantly, Tiktaalik has two novel traits that were to prove useful in helping its descendants invade the land. The first is a set of sturdy ribs that helped the animal pump air into its lungs and move oxygen from its gills (Tiktaalik could breathe both ways). And instead of the many tiny bones in the fins of lobe-finned fish, Tiktaalik had fewer and sturdier bones.”

HUMANS TOO
Humans also have vestigial organs that we no longer need. The tailbone; the remainder of an ancestral tail that we no longer develop. Wisdom teeth; extra chewing power we no longer need and remove.

CONCLUSION
So, when looking at the facts, there is evidence beyond a shadow of a doubt that with the presence of dark DNA, vestigial organs, and transitional fossils that the theory of evolution is true. If everything popped onto the earth at once, then there would be no transitional fossils or vestigial organs that serve no purpose except for a predecessor or older, less evolved species. Why would there be so many mutations in DNA that can only point to a sharp evolutionary jump, from an ice age long past or even the climate change going on right now. In the words of Pierre Teilhard de Chardin, “Evolution is a light illuminating all facts, a curve that all lines must follow.”

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