Sewage water bacteria helps fill 'missing link' in early evolution
A Planctomycete: a member of the PVC [Planctomycetes, Verrucomicrobiae, Chlamydiae] group of bacteria
(PhysOrg.com) -- A common group of bacteria found in acid bogs and sewage treatment plants has provided scientists with evidence of a missing link in one of the most important steps in the evolution of life on earth - the emergence of cells with a nucleus containing DNA (eukaryotic cells).
For billions of years, bacteria (single celled organisms without a nucleus) were the only cellular life form on earth. Then, about 1.6 2.1 billion years ago, eukaryotic cells emerged. These cells (with a nucleus) heralded the evolution of multi-cellular life on earth including: plants, insects, animals and humans.
Until now scientists have been unable to identify an ancestral cell linking the early prokaryotes with the later eukaryotes, so fusion theory - where two cells merge to form a new cell is often put forward to explain the appearance of these new cell types.
But new findings by scientists from University College Dublin and the European Molecular Biology Laboratory in Heidelberg, Germany, published in the journal Science (26 November 2010), have put paid to the fusion theory explanation, and suggest that an intermediate or missing link cell did exist all those billions of years ago.
Our discovery means that the appearance of eukaryotic cells on earth can be explained by Darwinian evolution over billions of years rather than a big bang fusion theory, says cell biologist Dr Emmanuel Reynaud, from the UCD School of Biology and Environmental Science, University College Dublin, one of the co-authors of the scientific paper.
Our analysis shows that PVC [Planctomycetes, Verrucomicrobiae, Chlamydiae] bacteria, members of which are commonly found in todays sewage treatment plants or acid bogs, represent an intermediate type of cell structure. They are slightly bigger than other known bacteria, and they also divide more slowly.
The structure of PVC suggests that it is an ancestor of a missing link cell which connected prokaryotic to eukaryotic cells along an evolutionary path all those billions of years ago, says Dr Damien P Devos, European Molecular Biology Laboratory, Heidelberg, Germany, the other scientist involved in the findings.
More information: Intermediate steps Published in Science (26 Nov 2010)
Damien P Devos, European Molecular Biology Labratory, Heidelberg, Germany; and Emmanuel G Reynaud, UCD School of Biology and Environmental Science, University College Dublin, Ireland.
Provided by University College Dublin
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Dec 07, 2010
Rank: 2.7 / 5 (3)
Dec 07, 2010
Rank: 5 / 5 (3)
And the god of the gaps just got a little smaller yet again....
Dec 07, 2010
Rank: 1 / 5 (3)
Dec 07, 2010
Rank: 5 / 5 (5)
How fortunate for us to know where we came from. Somehow I always knew we were full of it.
Dec 07, 2010
Rank: 1.8 / 5 (4)
What is it about the "structure" that suggests this finding?
Can we say vague bull****?
Dec 07, 2010
Rank: 4.3 / 5 (4)
Hmm. For whatever strange reason it seems like your questions are rhetorical. And what's with the proof fetish? I thought by now you would have learned that science is about evidence; proofs are for math.
And just look what I did for you: http://www.scienc....summary
You're welcome.
Dec 07, 2010
Rank: 1 / 5 (3)
I suggest we start spending money on people who can give more than suggestions...
And thanks for the link to the abstract...I guess? Didn't do any more for me than the article, but whatever.
Dec 07, 2010
Rank: 3.3 / 5 (3)
As for the claims of this paper, what's to say that these organisms haven't acquired some of the characteristics of Eucharistic cells by convergent evolution?
Dec 07, 2010
Rank: 5 / 5 (6)
I read the paper. The authors point out a lot of strongly suggestive structural similarities between certain gram-negative bacterial phyla and both eukaryotes and archaea. Basically, these structures look like intermediates between unique structures found in eukaryotes and archaea, respectively. Some of the structures discussed in the paper are the peptidoglycan-based cell wall of bacteria, bacterial cytoskeletal protein FtsZ and eukaryotic tubulin, the endomembrane system that compartmentalizes the cytoplasm, the PVC and bacterial periplasms, and vesicle-like structures.
Dec 07, 2010
Rank: 1 / 5 (4)
So in your world something can be plausible even if unproven? What about God? Seems that then becomes a matter of opinion about plausibility and less about facts or science.
Yeah, that's what I'm saying. You can't have your cake and eat it too.
Dec 07, 2010
Rank: 3.9 / 5 (7)
In my world, something can be *possible* until evidence shows otherwise. Evidence can't prove anything.
But it can disprove anything.
The existence of a god can't be disproven because it's not a falsifiable hypothesis. The existence of a specific deity, however - such as YHWH or Allah - could be disproven *if there were specific falsifiable claims about the nature of the deity.*
For example, if YHWH is claimed to have created life in its current form, and the evidence shows that life evolved from earlier, different forms, that would be evidence against that claim. If you combine that with claims that YHWH is also omnipotent, omniscient, and truthful, then it counts as evidence against his very existence.
Dec 07, 2010
Rank: 5 / 5 (5)
Wow. Well, to add my two cents, I agree that suggestions can definitely be plausible before there is evidence or "proof". It happens ALL THE TIME in science. Watson and Crick suggested that DNA is replicated in a semi-conservative manner. There was no evidence supporting that suggestion, yet it was that very suggestion, a single line in their paper on the structure of DNA, that won them the Nobel Prize. And it was a very fruitful suggestion, extremely plausible, ultimately correct, and had no evidence to support it at the time. Things can be true even if not proven, it's called insight.
Dec 07, 2010
Rank: 1 / 5 (5)
Ah, I see sorry. I'm just suggesting God exists then. That puts it on the same level as the postulates in this article...
Dec 07, 2010
Rank: not rated yet
The gaps do indeed shrink, but they also become more numerous.
Where as before there was 1 big gap, there are now 2 small gaps; one on each 'side' of the discovered 'missing link' that will be pointed at by the cretinists.
Dec 07, 2010
Rank: 4.5 / 5 (2)
Dec 08, 2010
Rank: 1 / 5 (6)
Right off the bat, the whole postulate falls on its face: Billions of years cannot be shown to be true but can only be adopted as a philosophical stance.
No matter how much the researchers speculate about possible similarities being an indication of connection between two organisms, they cannot conclusively say that that is how the nucleus arrived on earth - they simply do not have documented evidence that it was so. They can only speculate. No one can go back into the past to "prove" that what they say is true. So don't take it as truth.
Dec 08, 2010
Rank: 4.2 / 5 (5)
Can you read? Do you understand what the following means?
Dec 08, 2010
Rank: 1 / 5 (1)
So you're saying he could exist then. Unless you are saying you can prove something you can't. Which is it?
Dec 08, 2010
Rank: 4 / 5 (4)
And yes, he could exist then.
In the same sense as any creation of one's mind could exist.
Dec 08, 2010
Rank: 1 / 5 (2)
In any sense he could, the word existence means what it means. That's why we use words instead of grunts and clicks...
Which is something you seem to be having difficulty with.
Dec 08, 2010
Rank: 5 / 5 (1)
The music existing in my head, however, will be gone with me.
That's not the same kind of existence.
Objects which are postulated in non-falsifiable statements don't have an existence like the books of my example. But they have an existence like the music of my example.
Dec 10, 2010
Rank: not rated yet
If your faith in God or science gives hope for a better existance to those who cannot find it elsewhere, then I'm all for good things. If your faith in God or science expects the abuse, denegration or destruction of others for believing differently then that is a false faith and we will be enemies.
Dec 10, 2010
Rank: not rated yet
Dec 11, 2010
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