Salvador seems to have successfully hijacked the early embryonic mutations thread and turned it into a discussion of junk DNA. So I thought I’d share my thoughts on the subject of junk DNA. Why care?
Various strains of creationism hold that the earth and life started out perfect, then came the fall, and it all went downhill from there. Both young earth and old earth forms can easily accommodate the presence of junk in DNA. So the presence of junk DNA does not mitigate against the creationist position. But what of it’s absence?
Now perhaps it would appear to be nothing short of miraculous if it turned out that the genomes of organisms were mostly or completely functional or otherwise serve some identifiable purpose. But are we even close to being able to demonstrate that such is the case? Anywhere close at all? I think not. Thus the opportunity for much hot air and no end of people willing to spout it. We are far from having a complete understanding so perhaps a wait and see attitude is appropriate.
So arguments over how much DNA is junk and how much isn’t don’t serve much useful purpose in the debate. People aren’t going to be converted. If we simply must talk about junk DNA wouldn’t it be better just to discuss the implications one way or another? If neither side can make predictions that can be falsified what is the point? Ah. Pointless debate. Of course.
Does evolutionary theory predict junk DNA, and if so how much junk does it predict?
What does a phylogeny of junk DNA look like?
If it turned out that the genomes of organisms were mostly or completely functional or otherwise serve some identifiable purpose would evolutionary theory be falsified? My answer to that question is no, evolution would not be shown to be false.
The debate is mostly a waste of time. The irony. 🙂
From the glossary of the aforementioned book:
I can respect that definition. 🙂
That means Darwin was a Creationist.
Just like theistic evolutionists
So you accept that Theodosius Dobzhansky was a creationist?
Frankie,
According to Larry’s definition everyone is a creationist with two categories
1. Creationist that believes the universe was designed for a purpose
2. Creationist that believes the universe is a product of chance.
I guess there is a 3rd category that has no opinion.
3 Both of the above
4 Neither of the above
Hey, no one can falsify the claim that Stonehenge was designed. No one even knows how to test the claim that non-telic processes produced it. Does that somehow invalidate the design inference for it?
And guess how we know people were capable of producing Stonehenge? Stonehenge!
We know the capabilities of designers and crafters by what they leave behind. And again to falsify any given design inference is by slicing off the designer requirement. Using the explanatory filter the design inference isn’t even considered if non-telic processes can account for whatever is being investigated.
But anyway- back to the topic:
Histones- do the junk DNAers think histones arose just to spool up the junk?
Or did they just arise and the extra DNA just started wrapping around them?
From what I have read the DNA on the histone spools is actively moving, winding and unwinding to get the correct sequences exposed and aligned for transcription. And nucleosomes also align. How did blind and mindless chemistry figure all that out?
The point is you just can’t mindlessly keep adding to the genome without a way to package it and control that packaging so your coding sequences don’t get lost.
Larry? Anyone?
Where do new genes come from? From copies of other genes, of course.
This puzzles me. Is that assuming your conclusion? Begging the question?
But why would we need to assume that new genes hardly ever arise from scratch in order to come up with the best explanation for why most of our genes resemble other genes? What does it even mean for a new gene to arise from scratch and why don’t we just rule it out completely rather than claiming it hardly ever happens? That leaves room for it could happen. Maybe if it does happen. But rarely.
But why is that a problem, since in the very next paragraph he tells us that that gene duplication itself is also “a rare event.”
Now if the cell is more likely to duplicate an entire gene, and an actual gene at that rather than some random slice of DNA, that sure sounds like a non-random bias to me. On that has absolutely nothing to do with natural selection.
Unless you want to argue that it was natural selection which gave us this miraculous system of non-random bias in which genes which resemble other genes are more likely to be beneficial. Because think about it.
If most of our genes resembles other genes in our genome, what are the implications of that?
But Frankie, don’t you know that “prokaryotes do not contain histones (with a few exceptions)..”?
So now you have DNA control evolving twice, with one functional system (as used in prokaryots) replaced by another functional system (as used by eukaryotes).
Oh, and “Prokaryotic genome is very compact – contain very little non-coding DNA sequences..”
Also:
Evidence for an early prokaryotic origin of histones H2A and H4 prior to the emergence of eukaryotes
It needed a better way to store all that junk?
But. Not. Octamer. Spoolage
That’s just restating the problem. Yes it needed a better way to store all that junk so how did blind and mindless chemistry figure all that out?
Don’t stomp your feet and go all Patrick on me. Patrick was going to learn me something and now I am left feeling un-indoctrinated.
Patrick apparently prefers to not store all his junk. He prefers to unload it. He learned it in the classroom. Its very elementary thinking.
So, why the interest in junk DNA among IDists. I think I came across the answer.
Jonathan Wells, the infamous author of Icons of Evolution is also the author of The Myth of Junk DNA. It would appear that “junk DNA” is the last remaining icon of evolution.
Those poor evolutionists and their icons. As science advances they retreat. The irony.
This now in
Larry Moran weighs in @ Sandwalk