“Junk” DNA: Darwinism’s Last Stand?

We are often told that the evidence for evolution is “overwhelming.” If “evolution” is defined as “change over time” or “minor changes within existing species,” this is a truism. But what if “evolution” means Charles Darwin’s theory? According to Darwin, all living things are descendants of a common ancestor that have been modified by unguided processes such as random variation and natural selection.

Despite the hype from Darwin’s followers, the evidence for his theory is underwhelming, at best. Natural selection—like artificial selection—can produce minor changes within existing species. But in the 150 years since the publication of Darwin’s Origin of Species by Means of Natural Selection, no one has ever observed the origin of a new species by natural selection—much less the origin of new organs and body plans. As a result, the only evidence that all living things are biologically descended from a common ancestor comes from comparisons of the similarities and differences among fossil and living species. When making such comparisons, however, Darwinists start by assuming common ancestry. Then they try to fit similarities and differences into the branching-tree pattern that would result from it, and they ignore the glaring inconsistencies that often remain.

So the evidence for anything more than minor changes within existing species is surprisingly flimsy. In most other scientific fields, a theory with so little empirical support would probably have been discarded by now. To make matters worse for Darwinism’s defenders, their theory now faces a new challenge: intelligent design (ID). According to ID, evidence from nature shows that some features of living things are explained better by an intelligent cause than by unguided natural processes.¹

Junk DNA to the Rescue?
Darwin was mistaken about the origin and hereditary transmission of variations, and it wasn’t until his followers embraced Mendel’s competing theory of genetics in the 1930s that evolutionary theory began to rise to the prominence it enjoys today. According to modern neo-Darwinism, genes that are passed from generation to generation carry a program that directs embryo development; mutations occasionally alter the genetic program to produce new variations; and natural selection then sorts those mutations—the raw materials of evolution—to produce organisms better adapted to their environment.

In the 1950s, molecular biologists discovered that sequences of nucleotide subunits in an organism’s DNA encode proteins, and they equated “gene” with “protein-coding sequence.” When genetic mutations were traced to molecular accidents in the DNA, neo-Darwinian theory seemed complete. In 1970, molecular biologist Jacques Monod announced that with its “physical theory of heredity” and “the understanding of the random physical basis of mutation that molecular biology has also provided, the mechanism of Darwinism is at last securely founded. And man has to understand that he is a mere accident.”²

With design seemingly eliminated, Oxford professor Richard Dawkins wrote in 1976 that the only “purpose” of DNA is to ensure its own survival. Dawkins considered the predominant quality of successful genes to be “ruthless selfishness.” It follows that “we, and all other animals, are machines created by our genes. Like successful Chicago gangsters, our genes have survived, in some cases for millions of years, in a highly competitive world.” A body is simply “the genes’ way of preserving the genes unaltered.” Thus natural selection favors genes “which are good at building survival machines, genes which are skilled in the art of controlling embryonic development.” And genes control embryonic development by encoding proteins that build the body.³

By the 1970s, however, it was clear that most of the DNA in humans and many other animals does not code for proteins. In 1972, Susumu Ohno remarked that there is “so much ‘junk’ DNA in our genome.” ⁴ Dawkins was aware of this, but he argued that such junk was consistent with the logic of neo-Darwinism. “The amount of DNA in organisms,” he wrote, “is more than is strictly necessary for building them: a large fraction of the DNA is never translated into protein. From the point of view of the individual organism this seems paradoxical. If the ‘purpose’ of DNA is to supervise the building of bodies, it is surprising to find a large quantity of DNA which does no such thing. Biologists are racking their brains trying to think what useful task this apparently surplus DNA is doing. But from the point of view of the selfish genes themselves, there is no paradox. The true ‘purpose’ of DNA is to survive, no more and no less. The simplest way to explain the surplus DNA is to suppose that it is a parasite, or at best a harmless but useless passenger, hitching a ride in the survival machines created by the other DNA.”⁵

In 1980, Francis Crick and Leslie Orgel argued in Nature that “much DNA in higher organisms is little better than junk.” The spread of junk DNA in the course of evolution “can be compared to the spread of a not-too-harmful parasite within its host.” Since it is unlikely that such DNA has a function, “it would be folly in such cases to hunt obsessively for one.” In a companion article, W. Ford Doolittle and Carmen Sapienza similarly argued that many organisms contain “DNAs whose only ‘function’ is survival within genomes,” and that “the search for other explanations may prove, if not intellectually sterile, ultimately futile.”⁶

Some biologists wrote to Nature expressing their disagreement. Thomas Cavalier-Smith considered it “premature” to dismiss non-protein-coding DNA as junk, and Gabriel Dover wrote that “we should not abandon all hope of arriving at an understanding of the manner in which some sequences might affect the biology of organisms in completely novel and somewhat unconventional ways.” Orgel, Crick and Sapienza replied that “most people will agree” that higher organisms contain “parasitic” DNA or “dead” DNA. “Where people differ,” they wrote, “is in their estimates of the relative amounts. We feel that this can only be decided by experiment.”⁷

In 1980, the techniques for DNA sequencing were tedious and slow, but they improved rapidly. In 1990, the U.S. Department of Energy and National Institutes of Health established the Human Genome Project (HGP), with the goal of sequencing the entire human genome by 2005.⁸

Throughout the 1990s, however, many biologists continued to regard much of human DNA as non-functional “junk.” For example, according to the 1995 edition of Voet & Voet's Biochemistry “a possibility that must be seriously entertained is that much repetitive DNA serves no useful purpose whatever for its host. Rather, it is selfish or junk DNA, a molecular parasite.” Indeed, it may be that “a significant fraction, if not the great majority, of each eukaryotic genome is selfish DNA.”⁹

In the coming days I'll address the junk-DNA hypothesis in more detail.

Oh, okay. I thought you wanted something like a flying elephant or whale.

It's not a matter of me wanting that...but rather wanting to know what limits all this, let alone makes it possible and it does bring up an interesting question, what is it that limits any animals from growing some wings and, regardless of size, from flying period?

Dunno. Why should it?

If it's all supposedly without intelligence, totally random, without design, without purpose, then it's more than fair to ask these questions, particularly when so many liberals DEMAND children be programmed into their cultish way of thinking; all too often to the point of suing others who dare ask these kinds of questions of them, (let alone offering a better explanation, ie. intelligent design/creationism, etc).

Why don't humans just sprout wings for instance? Right now I can think of several reasons why wings would be beneficial and advantageous...driving in and around Atlanta often has me wondering why I don't have the ability to fly over messes. We can design devices to do exactly that, with our God-given intelligence. So by playing by your own rules of no intelligence allowed, why don't we have wings by now?

If ALL life came from a single celled organism, and all this variety comes from a single common ancestor, some animals through natural selection developed the ability to fly while others did not.

Why?

And saying "we don't know yet" or "just wait" or "be patient for another ga-jillion years" is a total cop-out. (We've had enough ga-jillion years to see plenty of variety!) Particularly when squealing any other view outside evolution isn't "science".

What is it about so-called "natural selection" that ultimnately determines which animal eventually flies and which do not and why? And what is it exactly that determines the rate of this so-called natural selection process which allowed for instance bats to fly?

And it's not just a certain animal kingdom, phyla, etc...insects, mammals as well as birds can fly for instance, moreover some animals with wings can't fly, while others without wings, come real close (flying squirrels), etc.

Why is that?

but rather wanting to know what limits all this, let alone makes it possible and it does bring up an interesting question, what is it that limits any animals from growing some wings and, regardless of size, from flying period?

Well, some of it is simple aerodynamics and structural considerations. Think of the size of the wings an elephant would need in order to fly, then think about the muscles it would need to control those wings, and the skeleton that would be needed to support the muscles and the forces on the wings...at some point, it just doesn't work.

If it's all supposedly without intelligence, totally random, without design, without purpose, then it's more than fair to ask these questions,

But if it is random, then asking why we didn't get a certain result is like asking why the dice didn't come up 11. They just didn't, that's all.

Why don't humans just sprout wings for instance?

No animals just "sprouted wings." If you look at the non-insect animals that fly, you'll notice that they have four limbs, just like us, and the two front limbs (or part of them) act as wings. So given that we're stuck with a four-limb body plan, we'd have to be in an ecological niche in which the changes necessary to turn our arms or hands into wings were favored over keeping them the way they are.

Why?

I tend to agree that it's a philosophical difficulty with evolution that we don't know what features natural selection favors until after the fact. But it's not a practical difficulty, just a philosophical one. It's like asking why a river follows a certain course--because it's the path of least resistance. How do we know it's the path of least resistance? Because the river followed it.

Yes of course, but WHY "at some point does it just not work" and at what point, and why aren't there more animals flying up to that point and frankly a few a fraction beyond this arbitrary point? When airplanes first flew, it made no sense that we saw 747's flying within 2 weeks of the Wright brothers, but this is ga-jillions of years we're talking about...we should be seeing more animals flying, heavier animals flying and for that matter animals swimming, AND flying and running their own businesses on the side by now, logically speaking.

Moreover, when it DOES work, why not say for instance didn't all mice, or even some mice or some rats, etc. develop wings like their bat cousins did?Or how about little foxes? Wombats? Why didn't they develop pouches like kangaroos, this would be very useful I would think when flying.

But if it is random, then asking why we didn't get a certain result is like asking why the dice didn't come up 11. They just didn't, that's all.

WOW, how utterly convenient for you! They just didn't that's all? Kind of like all the belly-aching from libs: "God-did-it" only in reverse! GOT it.

Yeah, I know, I know, ga-jillions of years, wings didn't just sprout overnight, which is missing the point, what determined wings in some animals and not in others? And your ecological niche argument falls flat because mice and bats, before bats developed wings, were living in the same eco-niche. The same premise falls flat with humans losing tails. There's no magical eco-niche that determines this either. It's all made up pie in the sky nonsense.

LOL! Circular reasoning at it's best! And make no mistake very much indeed it is a practical problem, so much so that people are doubting your excuses and nonsense. PRACTICALLY SPEAKING even small children know better. NO WONDER it's necessary to silence all dissent!

Very enlightening, thanks!

WHY "at some point does it just not work"

Really? Okay: because what we have to make animal wings out of is bone, muscle, and skin. At a certain size, a wing made out of those materials is going to be unable to support its own weight--the structural material (bone) isn't strong enough. And at a certain size, the muscles that make those wings flap are going to have to be attached to the body at a place strong enough to support the stresses involved. Do you understand that there are similar limitations to the size of an airplane?

hould be seeing more animals flying, heavier animals flying and for that matter animals swimming, AND flying and running their own businesses on the side by now, logically speaking.

Um...why? Just because something could evolve, doesn't mean it will evolve. This is something you made up, not something evolution promises.

why not say for instance didn't all mice, or even some mice or some rats, etc. develop wings like their bat cousins did?

Because there are still ecological niches for mice and rats as they are. The bats managed to exploit a new one, but that doesn't mean the old one disappeared. You're stuck on this idea that there is some standard of "better" that evolution always tends towards and that every animal has to always be changing in that direction.

Why didn't they develop pouches like kangaroos, this would be very useful I would think when flying.

There is, in fact, a flying marsupial.

WOW, how utterly convenient for you!

You asked a dumb question--don't blame me because you don't like the answer. You really think there's an answer for why a random event doesn't happen?

As the rest of your post trails off into your usual combination of ignorance, bluster, and rudeness, I'm starting to regret that I ever tried to answer your questions reasonably and respectfully.

But the point is, why haven't animals evolved to overcome all these limitations? After all, they started out as single celled organisms that overcame ALL KINDS of other things to eventually swim, fly and so forth in the first place.

Intelligence and design have allowed man to fly gigantic heavy planes, which was impossible with the technology available in 1903. And now, we're flying space shuttles in space, in the span of less than 100 years. An analogy for evolution would be a kangaroo jumping twice as far as before over 50 million years.

So what's preventing them from taking the next step?

So why can't animals evolve lighter weight, but superstrong bones to support more weight?

Kind of like we created a lightweight plane in 1903 that eventually led to the technology that allowed a multi-ton 747 to fly...WHY isn't this occuring in nature?

Do you forsee kangaroos that can jump the length of a football field in the next ga-jillion years?

Um...why? Just because something could evolve, doesn't mean it will evolve. This is something you made up, not something evolution promises.

Uhhhh WHY NOT? If it could evolve, what's stopping it? If it's supposed to be beneficial to the animal as evolution very much DOES claim with natural selection, why don't a few animals swim, fly AND flip pancakes?

But why did some fly and some remain behind? You can't say it was because of a niche, because some that occupied the same niche did, some didn't. What you get stuck on is excusing some invisible UN-natural force on limiting evolution. Of all the ga-jillions of possibilities, why aren't we seeing more and more impressive species jumps in shorter amounts of time? AND what makes it take ga-jillions of years in the first place? (Other than liberal convenience.)

You asked a dumb question--don't blame me because you don't like the answer. You really think there's an answer for why a random event doesn't happen?

As the rest of your post trails off into your usual combination of ignorance, bluster, and rudeness, I'm starting to regret that I ever tried to answer your questions reasonably and respectfully.

Thanks, I think this illustrates what children are up against when they encounter projecting liberal evo-cultists when serious examination takes place of their cult, as opposed to the sham of peer review.

Don't blame me for the obvious frustration you're having with your cult's inadequcies, get some help from a deprogrammer instead!

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