Talk:Three-domain system
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[edit] 36s ribosomal unit
However, by comparing the 36S ribosomal subunit it is clear that Eukaryota are genetically closer to Archaea than Archaea are to Bacteria, suggesting an early evolutionary divergence between Archaea and Bacteria and a later branching of Eukaryota from Archaea. Chloroplasts and mitochondria which inhabit almost all eukaryota are known to have evolved from Bacteria.
This misses the entire point of the criticism. If Bacteria are paraphyletic to Archaea, and Archaea paraphyletic to Eukaryota, then it's only natural that archaeans should have closer sequences to eukaryotes than bacteria do. So it doesn't support the three-domain system over the alternative two-empire-one-paraphyletic system, as this suggests. The 36S ribosomal unit info could still be valuable, but I'm not sure how to work it in. Josh
[edit] Typo?
I'm no biologist, but shouldn't the word "eukaryotes" in the first line read "prokaryotes"? Rbraunwa 00:27, 21 July 2006 (UTC)
It should; fixed. Josh
[edit] Clean up terminology
I'd like to echo what this person says (below): please rewrite for the layman! Thanks!
I generally know about prokaryotes and eukaryotes, but I have no expertise in the field. I had to read the article several times to make sense of the terminology; it reads like one expert describing it to another, throwing around jargon loosely.
It would help to, 1) Clearly define the terms and their relationships to each other. Also putting all the terms in the graphic would help tremendously by providing a quick reference. 2) Simplify, simplify, simplify: Eliminate synonyms and re-use the same terms as much as possible. For example, just this phrase creates much confusion:
biologists like Mayr criticized him for over-emphasizing the uniqueness of the archaebacteria and ignoring strong genetic similarities between the groups
What are archaebacteria? Archaea? Bacteria? I looked at the graphic, but archaebacteria isn't there. I had to re-read the first paragraph (not a good sign) to find, ... originally called Eubacteria and Archaebacteria, which raised more questions: 1) They were originally called that: Are the terms obsolete? Why use them in the next paragraph? What are the proper terms? 2) Which term corresponds to what on the graph? Also, what exactly is a group? How does it relate to a domain?
I'm not asking for help -- I believe I figured it out. I'm asking that someone help the next non-expert reader. I would re-write it, but I'm not qualified.
Thanks, phrustrated in philly
[edit] Date Discrepancy
This article states that the Three Domain System was introduced in 1960. The article on Domains indicates 1990. Please correct the wrong one. Artworksmetal 18:51, 31 January 2007 (UTC)
- For the record, that appeared to be vandalism and 1990 was correct. I fixed it before I saw this post. 66.92.53.49 22:12, 11 February 2007 (UTC)
