The Kinks in Evolution Options

[Call911Quick]

I've been studying AP bio at a private international high school. We've learned a little bit about evolution, and after learning about it, I realize that there are problems with the theory. Here I will show you why Evolution is credible, and why it is also not "proven fact".

***If you are already fairly familiar in detail with the theory of Evolution, skip down to my series of dotted lines.***

First of all, let me inform you about DNA. 1.5% of your DNA are genes. Genes are what code for proteins and RNA molecules (enzymes). These are the mini machines in your body that regulate everything from the distance between your eyes to the length of your toes. There are around 30,000 genes in a human cell, give or take.

So, what is the other 98.5% of your DNA? It is actually composed of many different things. Random segments of non-coding DNA, transposons, satellite DNA, etc. At any rate, all you need to know is that the rest of your DNA does absolutely NOTHING good for you.

Now, I may be exaggerating, but 99% (or somewhere around that number) of our genes are identical to a fruit fly's genes. This is one of the bases for the theory of evolution; we are so similar to primates, flies, and even sea cucumbers. We must have a common ancestor.

The theory of evolution states that over the course of 1.5 billion years (That's a REALLY LONG TIME!), single cell procaryotes eventually evolved into simple multicellular organisms composed of specialized eucaryotic cells. The first animal: sponges.

From sponges, it went to worms. Worms were the first animals to have a central nervous system, radial symmetry, and most importantly, a head. From there it's a really long story but basically we evolved over the course of 1.5 billion years. This is actually quite probable; lots can happen in such a long time.

This is my mini introduction to the theory of evolution, just to clarify some things. It may be 1% of what is actually known, because I could write a 10-page essay on this thing.

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The problem with evolution likes in your DNA.

As you all know, genetic mutations cause diseases. Genetic mutations can occur in many different ways. The most common causes are mutagens, such as x-rays, car exhaust, etc. They're chemicals that cause genetic mutation.

Another way is from viruses. AS you know, viruses insert a segment of double-stranded DNA into your cell, which integrates itself with that particular cell's DNA. This causes the cell to produce more viruses, etc.

The step in which the virus' DNA integrates itself with your human DNA is where mutations can occur. Your cell doesn't produce viruses, but maybe it grows uncontrollably and eventually develops into a malignant tumor. Viruses are a leading cause for cancer.

Secondly, and more curiously, is your own DNA is capable of mutating itself. I mentioned earlier that a part of your DNA is transposons. Approximately 15%. If you have knowledge in Latin roots, you can figure out that transposons are segments of DNA that can be cut out and re-inserted by the enzyme transposase. This has no known positive benefit, and is just a formula for genetic mutations. Another cause for cancer.

If evolution were true, why did we develop this kind of DNA? The only reason why we don't have cancer is because a cell firstly needs 13-17 mutations in order to become cancerous, and the probability of transposons affecting a gene is low, because your cell's growth cycle has two restriction points, and if something is wrong, the it will commit suicide. Your mutated cell kills itself, unless the... well, if you want to know about cancer, PM me.

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Are you curious why human cells stop metabolism? Why do we age? Why do we die? Well, part of the cause is once again, ourselves. Our cells have receptors for hormones with, basically, tell the cell to stop metabolizing. A scientist (forget her name, she's a genius tho) experimented with roundworms. She ended up being able to DOUBLE the life of a roundworm (from two weeks to four weeks) by mutating the gene that codes for said receptors on the cell. The cells are incapable of receiving the hormones, and thus don't die THAT way.

There are other ways our cells die. Our sex cells, or gametes, also have a way of causing our body to stop metabolism. I wasn't paying much attention during this part of the lecture, so I can't go into detail.

Anyway, why does this happen? If evolution were true, we'd have never developed this aging process. We strive for survival. The animals that mutated and began aging should have died, while the animals that didn't would live much longer. According to Darwin, that is.

Think on it. Sleep on it. Take some aspirin.

[sheridan_whitesi...]

First off, you're not rocking my world with how smart you are. I'm not going to sleep on it, I'm not impressed by Mom and Dad's money, and reading how you've misinterpreted a biology class designed around a standardized test isn't making me rethink my understanding of science. And no, I'm not going to PM you so you can enlighten me about the functions of p53, how it repairs DNA or induces apoptosis.

Ok, now for setting you straight. Evolution isn't about "striving for survival," at least not for survival's sake. It's only about staying alive enough for reproduction. Ok, we realize you know about how mutations in proto-oncogenes cause cancer, and how most of the human genome doesn't code for proteins. Transposable DNA elements and those billions of non-coding base pairs actually absorb mutations from the environment. If a T turns to a C in a huge intron, it's not going to matter. Transposons help evolution because they can deliver a whole gene family to a different region of DNA. Let's say theoretically that muscle cells operated strictly out of involuntary reflex to immediate stimuli. There is no connection to the nervous system. However, one day a transposable element which contained some genes coding for central nervous reporting were inserted near the Myo D gene, a muscle-specific bHLH transcription factor. [look at how smart that sounds! I got a bj just typing it!] If this mutation occurred in the germ-line, the progeny would switch on central nervous control genes with the muscle-specific Myo D gene and the muscles would now contain precursors for more nerve development. That is an oversimplification, but it shows how a gene family could theoretically transpose itself into a new useful function, instead of waiting for enough single-base changes to make opposable thumbs.
Sure, a transposable event could move a bit of chromosome 20 on chromosome 8 and give you leukemia. We still have them because most transposon events aren't in the germline and therefore not heritable. If my uncle Pete gets cancer because of a transposition, it's not going to matter to my cousin Doug. Pete's already reproduced and served his evolutionary purpose. Our wonderful defenses against cancer, proofreading enzymes, p53 and other tumor-supressor genes are there because they helped us fend off cancer until we made some babies.

I could seriously write a 10 page [wow how long!] paper about this stuff but I'll spare you about how awesome I am for now.