Freethought & Rationalism Archive

Camaban · 06-18-2002, 06:48 PM

well..

it's got to have happened ONCE at least...

hasn't it?

Quetzal · 06-18-2002, 11:34 PM

Dr. GH: Great minds think alike, and all that. Here's the email I sent to the U. Ill. PR guy:

Quote:

Dear Mr. Barlow:

I would first like to say I'm excited by the findings of Dr. Woese's research. Additional evidence that the roots of the "tree of life" being more akin to mangrove than taproot is both very welcome and much needed. It adds additional weight to such theories as serial endosymbiosis, etc.

However, I fear I must take exception to the provocative title with which you have chosen to announce the research. I am relatively active in the evolution-creation debate, especially as it pertains to the teaching of "creationism" in US public schools and refuting the spurious claims of its practitioners. I strongly believe that the mere title of the release will soon add ammunition to the opponents of rationality and science. The same people who consistently misrepresent scientists to push their religious and political agendas - such as the most recent incident in Ohio - will seize on the title (ignoring both the content of the research and the intent of Dr. Woese) as "another evolutionist declares Darwinism dead and the theory of evolution false".

I'm sure it was neither the university's nor Dr. Woese's intent to aid and abet the antiscience movement, yet that is precisely the effect I predict from your unfortunate choice of title. I'm not sure there is any way to recover at this point, so I would ask that you consider carefully in the future how such announcements can be mis-perceived by those whose goal is to circumvent the constitution by "proving" evolution is bad science OR demanding equal time for their religious views (a la Santorum document).

Please extend my congratulations to Dr. Woese on his research.

Sincerely,

I haven't gotten a response, yet. My message went out 6/18 at 5:20 pm local (Ukraine) time.

lpetrich · 06-19-2002, 01:02 AM

The issue with PNAS that contains that Woese article will come out online on Tuesday next week, at least if PNAS continues to follow its biweekly schedule.

But according to his recent interview, he proposes that these important information-processing systems have emerged in this order:

Translation (RNA -> protein)
Transcription (DNA -> RNA)
Replication (improved DNA duplication?)

His proposals are a close fit with the "RNA world" idea; in particular, he apparently argues that proteins were invented before DNA. Or more precisely, that RNA specification of proteins came before DNA becoming the master copy of RNA. This view may cause some controversy among RNA-world advocates, but I've yet to see much discussion of this ordering question in the RNA-world literature that I've read.

What he says about the origin of eukaryotic cells is very likely to be interesting -- if he addresses that question in that article.

Here's a <a href="http://www.biomedcentral.com/1471-2148/1/4" target="_blank">reconstruction of early eukaryotic-cell evolution</a>; it proposes that the earliest ones had emerged from the fusion of some archaebacterium and some Gram-negative eubacterium (one each from the two big divisions of the prokaryotes).

As to how it happens, <a href="http://www.genomics.ucla.edu/orignucl.html" target="_blank">this site</a> suggests an answer: an endosymbiosis in which that archaebacterium took up residence inside of that eubacterium -- but unlike later endosymbiotic organisms, it became the main repository of genetic information, becoming the cell nucleus.

This scenario accounts for the nucleus's double membrane, why it has archaebacterium-like genetic-information handling, and while the eukaryotic cell membrane is eubacterium-like (membrane lipids: straight-chain esters) rather than archaebacterium-like (membrane lipids: branched-chain ethers).

That site identifies that archaebacterium as an "eocyte", which is what others would call a member of the Crenarchaeota, which mostly live in very hot places (the other big branch, the Euryarchaeota, contains the methanogens and some extreme halophiles).

However, others have found the eukaryotes to branch off before the root of the archaebacterial tree; but one complication is that the eukaryote branch is relatively long, suggesting long-branch artifacts might be happening.

06-19-2002, 01:02 AM	#23
lpetrich Contributor Join Date: Jul 2000 Location: Lebanon, OR, USA Posts: 16,829	The issue with PNAS that contains that Woese article will come out online on Tuesday next week, at least if PNAS continues to follow its biweekly schedule. But according to his recent interview, he proposes that these important information-processing systems have emerged in this order: Translation (RNA -> protein) Transcription (DNA -> RNA) Replication (improved DNA duplication?) His proposals are a close fit with the "RNA world" idea; in particular, he apparently argues that proteins were invented before DNA. Or more precisely, that RNA specification of proteins came before DNA becoming the master copy of RNA. This view may cause some controversy among RNA-world advocates, but I've yet to see much discussion of this ordering question in the RNA-world literature that I've read. What he says about the origin of eukaryotic cells is very likely to be interesting -- if he addresses that question in that article. Here's a <a href="http://www.biomedcentral.com/1471-2148/1/4" target="_blank">reconstruction of early eukaryotic-cell evolution</a>; it proposes that the earliest ones had emerged from the fusion of some archaebacterium and some Gram-negative eubacterium (one each from the two big divisions of the prokaryotes). As to how it happens, <a href="http://www.genomics.ucla.edu/orignucl.html" target="_blank">this site</a> suggests an answer: an endosymbiosis in which that archaebacterium took up residence inside of that eubacterium -- but unlike later endosymbiotic organisms, it became the main repository of genetic information, becoming the cell nucleus. This scenario accounts for the nucleus's double membrane, why it has archaebacterium-like genetic-information handling, and while the eukaryotic cell membrane is eubacterium-like (membrane lipids: straight-chain esters) rather than archaebacterium-like (membrane lipids: branched-chain ethers). That site identifies that archaebacterium as an "eocyte", which is what others would call a member of the Crenarchaeota, which mostly live in very hot places (the other big branch, the Euryarchaeota, contains the methanogens and some extreme halophiles). However, others have found the eukaryotes to branch off before the root of the archaebacterial tree; but one complication is that the eukaryote branch is relatively long, suggesting long-branch artifacts might be happening.

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06-18-2002, 06:48 PM	#21
Camaban Regular Member Join Date: Jun 2002 Location: Australia Posts: 473	well.. it's got to have happened ONCE at least... hasn't it?

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