Intelligent Design Creationists are heavily invested in refuting junk DNA because it casts doubt on their model of an intelligently designed human. Over the years they have advanced all kinds of arguments against junk DNA and some ID supporters actually address the real scientific issues (e.g. Jonathan Wells). However, most Intelligent Design Creationists are as ignorant about the scientific dispute over junk DNA as they are about evolution and lots of other science issues that conflict with their underlying religious beliefs.
A few days ago (March 26, 2024), the Discovery Institute's Center for Science and Culture published a short video on "The MYTH of Junk DNA" where they ignored most of the science and appealed to the majority of creationists who don't care about the truth. We have enough data to conclude that the Discovery Institute isn't just ignorant of the real science but is actually lying in this video. We know this because there are prominent Senior Fellows of the Center for Science and Culture who know that the material in this video is wrong and/or mispleading.
Watch the video to see what I mean. Think about the following points as you watch it and decide for yourself whether an honest, intelligent, ID proponent should know these things. If you decide that they should know these things then ask yourself why they would make a video like this.
Scientists like Richard Dawkins opposed junk DNA in the beginning because it conflicted with their view of evolution as a process that was dominated by natural selection. They thought that junk DNA should be eliminated from the genome by natural selection because it is detrimental. This is still the dominant view of many scientists. Junk DNA was never a "prediction" of evolution, just the opposite, most evolutionists "predicted" that the unknown parts of the genome would be found to be functional. The development of the neutral and the nearly-neutral theories provided justification for the existence of junk DNA and refuted the adaptationist objection but it did not "predict" junk DNA.
The creationists are trying to convince their followers that evolution predicted junk DNA and that prediction turned out to be wrong so evolution must be wrong. That's misleading enough to qualify as a lie.
- Mutation load arguments were advanced in the late 1940s and gained force in the 1960s. Based on known mutation rates, most of our genome must be immune to deleterious mutations because if it were functional our species would be extinct. This was one of the main bits of evidence behind the proposal of junk DNA. Watch how the ID proponents deal with the mutation load evidence in the video.
- Only 10% of our genome is conserved and that same 10% is currently under purifying selection. This is consistent with the view that 90% of our genome is junk. You should expect a serious scientific presentation of this evidence along with a serious scientific attempt to refute it, right?
- The huge differences in genome size in related species are mostly due to different amounts of repetitive DNA and we now know that much of this repetitive DNA consists of fragments of transposons and viruses that are evolving at the neutral rate. Those bits and pieces of degenerate DNA sure look like junk to me. Watch to see how the ID explanation accounts for that data.
- There was a big debate in the late 1960s over the amount of regulatory DNA in the human genome. The proponents of junk DNA participated in that debate and concluded that only a small percentage of the genome is required for regulation. This was included in the 10% of the genome that was assumed to be functional. The ID proponents surely know about this since they have been told many times that regulatory DNA was well-known 50 years ago. I bet you're anxious to see how this knowledge is incorporated into the current video.
- We've known since the late 1960s that only about 2% of the human genome encodes proteins. From the very beginning we knew of functional non-coding DNA such as non-coding RNA genes, regulatory sequences, centromeres, origins of replication etc. At no time did any knowledgeable biologist ever say that all non-coding DNA was junk. We've been explaining this to Intelligent Design Creationists for many decades but they have continued to spread the myth that all non-coding DNA was thought to be junk. Now, at last, having read my book and Wikipedia, you can expect them to stop spreading that myth, right?
- What is a "prediction"? Supporters of junk DNA advance their model in order to explain the evidence. We hypothesize that the data is best explained by the presence of a large amount of non-functional DNA (junk) in the genomes of many species. That's not a "prediction"—it's a scientific hypothesis based on real scientific data. The junk DNA model has held up remarkably well in the past 50 years so that it's now widely accepted among experts in molecular evolution and other scientists who are knowledgeable about the subject of genome organization and structure.
Intelligent Design Creationists don't like the idea of junk DNA so they have "predicted" that the junk DNA hypothesis will be proven wrong at some time in the future. This "prediction" is not based on a scientific analysis of all of the available evidence but rather on some vague reliance on the importance of design in nature.
- The cherry picking fallacy is a well-known error in logic where defenders of a particular position pick out selective data in support of their argument and ignore the larger body of evidence against it. There are two main examples in the video. The first is that the main evidence for junk DNA is ignored completely. The second is that while scientists are actively researching the genome in order to fill in the 10% of the genome that is functional, the ID crowd proclaims every discovery as proof that the entire model of junk DNA is wrong.
Dr. Dan (Daniel Stern Cardinale) has posted a video making many of the same points that I make in this post (see below). There's only one thing in Dan's video that I strongly disagree with and that's the distinction that he makes between "junk" and "garbage." I do not think that's a useful scientific distinction although I agree that the image in the DI video is deliberately misleading.
At the end Dan spends a lot of time on the ENCODE definition of function and the followup 2014 paper by ENCODE researchers where they retracted their original "biochemical" definition of function. You didn't see any mention of that in the Discovery Institute video, did you? I wonder why.
9 comments :
They refute it because they have absolutely no evidence for their claims, so the false dichotomy fallacy is their major, some might say only, strategy. And being a senior fellow of the CSC is probably about as prestigious as being assistant to the undersecretary to the events coordinator of the Yellowknife Lawn Bowling League, but with less credibility.
Dave Bailey
Like the person above said, they have no evidence. But also, by trying to sound sciency ID creationist have backhandedly admitted their religion cannot stand on its own. They've managed to shift attention away from the fact that their desert tribal war deity, Yahweh, does not exist.
Some IDers deny that the absence of junk is a prediciton of ID. After all, since God works in mysterious ways, who's to say he wouldn't make junk? He made lots of other parasites, so why would genomic parasites be excluded? The so-called prediction is just another consequence of the ID view of organisms as optimally efficient machines.
And on the topic of models that make predictions, ID proponents and creationists have none. There is no model. They have no theory or hypothesis that says how much junk DNA there should be. Literally no numbers at all. They have no error bars or anything, no equations, no curves. Nothing. It's only and entirely just some vacuous rationalization that some sort of perfect designer wouldn't leave a lot of junk behind. What's even worse is when pressed to discuss the amount, they will even allow for the possibility that there will be "some" junk. They can't say how much.
The whole thing is really just apologetics. It was never about the sciences of genetics, biology, or anything of the sort. ID is primarly concerned with religious apologetics. That's why they can admit multiple contradictory views (such as ID proponents that accept the age of the Earth and universal common descent, while also YEC that reject basically all findings of modern science) under their big tent. You can't do that if you have an actual model that says something about how genomes should look, how organisms should function, what is related to what and how far back, etc.
A new insight in to an old question: why did evolution not remove junk DNA?
pub:
Programmed DNA elimination: silencing genes and repetitive sequences in somatic cells
Maxim V. Zagoskin and Jianbin Wang, 2021
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9200590/
DNA elimination removes genes and repetitive elements in the germline genome to form a reduced somatic genome in various organisms. The process of DNA elimination within an organism is highly accurate and reproducible;
...
The eliminated sequences often contain genes and repeats..."
===
my question: if evolution has available a highly accurate and reproducible mechanism to eliminate junk DNA, why hasn't done so in more animals?
@gert korthof
They say "DNA elimination in the germline has yet to be discovered, likely because all known DNA elimination systems eliminate essential germline genes."
I've read what I thought were all the major papers on junk DNA from Kimura 1968 onward to the '90s and I've seen many predictions that most DNA was junk. Can someone show me where "most evolutionists 'predicted' that the unknown parts of the genome would be found to be functional?" Or any such predictions?
@Eric: It's important to understand that the idea of junk DNA was not widely accepted in the 1970s, 80s, and 90s. It was pretty much ignored by most scientists because it conflicted with their view of evolution. If natural selection was the dominant mechanism of evolution then all the extra DNA must be doing something or it would have been eliminated by selection.
This is the view that Thomas Jukes was talking about when he wrote to Francis Crick in 1979 and said,
"I am sure that you realize how frightfully angry a lot of people will be if you say that much of the DNA is junk. The geneticists will be angry because they think that DNA is sacred. The Darwinian evolutionists will be outraged because they believe every change in DNA that is accepted in evolution is necessarily an adaptive change. To suggest anything else is an insult to the sacred memory of Darwin."
The opposition to junk DNA was voiced by many molecular biologists as well. Natalie Angier (Pulitzer Prize winner for science writing) wrote a piece in the New York Times in 1994 where she interviewed several prominent scientists who opposed junk DNA. That was still the dominant view back then in spite of what creationists would have you believe.
Walter Gilbert said, "I don't believe in junk DNA. I've long believed that the attitude that all information is contained in coding regions is very shortsighted, reflecting a protein chemist's bias of looking at DNA."
Roy Britten said, "It may be on the edge to claim that what's been considered the pre-eminent junk is under selective pressure and is probably carrying our some function, but I take the general position that if there's something ubiquitous around, it will get used."
Craig Venter said, "I'm of the school of thought that junk DNA is absolutely necessary in evolution and recombination."
Keys Emerge To Mystery of 'Junk' DNA by Natalie Angier
https://www.nytimes.com/1994/06/28/science/keys-emerge-to-mystery-of-junk-dna.html
The description of the selectionist-neutralist controversy in this article looks like a good introduction:
https://www.nature.com/scitable/topicpage/neutral-theory-the-null-hypothesis-of-molecular-839/
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