tgamble

<a href="http://www.reasons.org/resources/connections/2000v2n1/index.html?main#junk_dna" target="_blank">http://www.reasons.org/resources/connections/2000v2n1/index.html?main#junk_dna</a>

Interesting claims here. Any thoughts on how it effects the argument of plagerized errors?
<a href="http://www.talkorigins.org/faqs/molgen/" target="_blank">http://www.talkorigins.org/faqs/molgen/</a> How accurate is the article (the last sentence excluded)?

Also on the same site:

"Fossils previously found in Yunnan province (at sites discovered nearly 100 years ago) and in the Burgess Shale deposits of the Canadian Rockies tell us that all animal phyla (more than 70) ever to exist in Earth’s history appeared “at once” about 540 million years ago."

I hope Patrick doesn't have a seizure or something over this.

[ July 11, 2002: Message edited by: tgamble ]</p>

ps418

I wont have a seizure. I will point out that there are nowhere near 70 phyla represented in the Yunnan province and Burgess Shale deposits, so these deposits alone 'tell us' no such thing. The real number is closer to about 20, depending upon how you split up the problematica (e.g. Wiwaxia).

The earliest sponges (phylum Porifera) appear somewhere around 570Ma, well before the base of the Cambrian, and the earlist bryozoans are known from the early Ordovician (~500Ma). Thats about 70Ma seperating the first appearance of phylum porifera and phylum bryozoa. Describing a ~70Ma -long 'event' as occurring 'at once' is a bit misleading.

The kernal of truth, of course, is that many phyla do make their first appearance in the early Cambrian, in a short span of time, maybe 5Ma or so.

tgamble

yes yes. But you mustn't confuse the poor man with inconvenient facts.

l-bow

Why would he have a seizure? "junk dna" should be properly called "non-encoding dna". And there's still the issue of psuedogenes.

Is this guy a creationist? I tried once to bring up the issue of adaptive radiations and how creationists can use to it to argue for instant creation. I got attacked by this guy for it.

pseudobug

I don't think that the proposal that the fundie summarizes from the research is totally implausible. Though, i haven't read the paper, I would be willing to bet that it needs a whale of a lot of work to solidify the notion that some of the "junk" DNA's purpose is soley to provide "elbow room" in the cell.

What is horscrap, though, is the author of the links extrapolation to the supposition that this study is evidence or supportive of the notion of ID.

I seem to also recall from a number of years ago seeing something in the literature about long range cis-acting sequences in "junk" DNA paricipating in activation of certain genes--though I don't recall specifics.

I think that sometimes "junk" DNA has sort of drifted to jargon use in some instances. From a very stringent defintion for the function of DNA as simply the portion of sequence that ultimately is translated; much of the DNA in a cell, including the regulatory regions, transcriptional terminators, etc, can be defined/classified as "junk".

WinAce

I suggest you read the refutations of creationist objections (section 5) in the TalkOrigins article very carefully to get an idea of just why scientists consider 'junk' DNA junk. While some sequences will no doubt be discovered to have a non-coding function, there is overwhelming evidence that the vast majority are just broken copies of other genes and miscellaneous other crap.

scigirl

Whether or not pseudogenens, introns, etc etc, have functions is irrelevant to whether they are evidence for evolution. Look at the patterns of the gene duplications, introns, and pseudogenes - the specific sequence identities correlate with evolutionary trees.

scigirl

lpetrich

One very nice side effect of the genome-sequencing efforts has been whole-genome comparisons. Here's a <a href="http://www.ensembl.org/Homo_sapiens/syntenyview" target="_blank">mapping of human-mouse chromosome regions</a>.

This mapping has been done with the discovery of a large number of highly-conserved regions -- including numerous highly-conserved noncoding regions.

But these are interspersed with lots of junky regions, like pseudogenes, dead retroviruses, and repeated parasitic sequences like "Alu".

One interesting feature of that map is that it looks very irregular and chaotic; one chromosome can map onto as many as 8 chromosomes, and regions from one chromosone can map onto differently-arranged regions from another.

One wonders what kind of illogical "creator" could be responsible for this stupid scrambling.