For hype? How is Makalowski wrong? You do realize that Makalowski is not the author of the article you’re citing, don’t you?
The author was definitely wrong in writing:
“With no obvious function, the noncoding portion of a genome was declared useless…In 1972 the late geneticist Susumu Ohno coined the term “junk DNA” to describe all noncoding sections of a genome, most of which consist of repeated segments scattered randomly throughout the genome.”
Junk was NEVER, EVER synonymous with “all noncoding,” as plenty of noncoding DNA has always been known to have function–promoters, for example. The author of the article is dead wrong.
Who’s “he”? The author meant to create some drama. Who did any ridiculing? Why did the author write about risk instead of actual ridicule?
No particular percentage. Darwinian theory predicts 0. Isn’t that ironic, since so many IDCreationists try to pretend that evolutionary theory=Darwinian theory?
But it works on genes, which just shows the validity of it. Do you not realize that a scientific theory is supposed to predict observations we have not yet made?
Because it is a function of the balance of Darwinian and neutral forces. There’s a whole book about this aimed at laypeople, you know, but I’m hesitant to recommend it given Dale’s affection for metaphors.
So it predicts anything from zero percentage to 100 percentage junk DNA?
What about studies which claim 8-10 percentage of the human genome is conserved and hence should be functional while the rest aren’t? These predictions are based on the impact of natural selection aren’t they?
Edit: if i understand correctly, around 8% of the human genome is contrained in evolutionary terms and Gaur et al gives a max percentage for functional DNA in the human genome of 25% based on the concept of the increasing cost of deleterous mutations as more of the Genome becomes functional.
So would it be fair to say that NS imposes a minimum limit of 8% genomes being functional and Neutral evolution imposes a maximum limit of 25% (while predicting 10-15% based on the no: of offspring required to maintain a stable human population).
Hence if more that 30% of the human genome is functional, its should cause problems to modern evolutionary theory.
In fact, if i understood correctly, even a % of 20+ should cause problems as it will be difficult to explain why human populations are stable
It’s actually a pretty bad article written by someone who didn’t know the history. That unfortunately happens too often. Even many molecular biologists today don’t have a good feeling for historical precident. It’s not really taught as part of their training. However, I’ve directed you to sources that did know the history. Check out Larry Moran’s Sandwalk pages on the topic. Also, Carl Zimmer, another popular science writer does a much better job in his National Geographic article.
If the functions are sequence-specific, that’s possibly an issue. If it’s a function involved with spacing out elements between long tracts of non-specific sequences, then possibly not.
We have a gene. We know that when both copies (alleles) are missing in humans or mice, babies are abnormal (observed at the earliest 4 weeks and 2 weeks respectively) and die at the earliest at 24 weeks and 3 weeks respectively.
If you “allow for design,” when and where should we see the gene turned on in normal mice and humans, including embryos?
Do you realize that article was written in 2007, before the ENCODE project results were published? The article was written by SA Science Editor A. Khajavinia, not by Makalowski.
That’s a wierd question to ask. I asked mercer the question to understand what evolution predicts about junk DNA.
If I wanted to understand what ID predicts, I would ask scientists who back ID.
It is a very word question, but it is the question that every well trained scientist will ask. ID makes not prediction, so it not an explanation of junk DNA.
So as usual an ID-Creationist demands an answer from evolutionary theory but is completely unable to provide any answer at all for the same question asked of ID.
I think it’s fair to say that some ID people think there is a case to be made against Junk DNA, just as there are some mainstream biologists who suspect there may not be much Junk DNA. However, there isn’t much of a case to be made theoretically, empirically or ‘paradigm-wise’ that most of the human genome is subject to constraints of sequence or length (within practical bounds). In contrast, the case that most of the (human, but also most mammalian) genome is likely selectively neutral has a pretty solid basis.
The fact is, the existence of junk DNA is certainly consistent with any number of ‘design modes’ or mechanisms. Junk DNA is not a ‘design defeater’. However there are some design modes or preferences which would not. One problem is that those specific, “junk DNA incompatible” modes are often not explicitly stated when making these particular ID arguments. Interestingly, a number of DI-associated “ID scientists” with biology degrees have made ‘predictions’ that over 90% of the human genome is probably functional. But I haven’t seen basis by which any particular ID theory makes those predictions. I really suspect it’s a ‘gut’ preference or a “anything but evolution” bias.
Doesn’t spacing out elements also involve getting a particular 3D orientation such that different elements can interact with each other.
Would mutations that can change the shape/orientation count as deleterious?
