You say in reply:
1) "What is the magic ingredient if not life of some kind?"
A carefull scrutiny will reveal that this proces has nothing in common with life. Probably it is a selfpropagating reaction.
2) "organic contamination from human fingerprints in the petri dishes suggests that nanobes have some need for organic substrates..."
..to attach to.
"..nanobes were originally observed in the sandstone samples"
Sandstone containing N and C?
3) "I think it is not an unwarranted observation.."
You are free to think whatever you like.
"It is a necessary part of the argument- looks like life-> behaves like life-> is chemically consistent with life---> might be life"
I do not follow your logic. Firstly, "it looks like life" is an utterly subjective observation. Maybe someone else doesn't think it looks like life. Maybe it resembles some filamentous micro-organisms, but so do carpet fibers. As mentioned before, even if you find molecules that have a similar consistency as biomolecules it doesn't say anything. It is a fallacy similar to: blood and seawater have similar levels of ions, so our ancestor was an aquatic ape (this has actually been proposed by some evolutionist). These fallacies are called non-sequiturs, meaning that the conclusions drawn are not followed from the evidence presented.
4) "The composition of the atmosphere is C:N of about 1:70:29 from memory. The nanobes C:N is about 60:10:30 (from figure 9 in the original article). This is about the same as it observed for living organisms. More importantly there is insufficient metal or counterion present to suggest the formations are mineral in nature."
One doesn't need ions to polymerise.
5) "In one image there is a suggestion of a darker area toward the centre of the cavity which they suggest as a possible nuclear area, but could just as easily be a sectioning artifact given the difficulties they report in preparing the TEM samples. The conclusion that they observed membrane bound structures is fairly hard to dispute though. Again this is a small but essential piece of the whole argument."
You cannot present the nanobes as having a nucleus based on this observation. They do not show any membrane bound structures. It is wishful thinking.
6) "This is a big misunderstanding. Stones have distinct crystalline structure on a microscopic scale. Other examples of microscopic bodies which were mistaken for organisms based on morphology alone have crystalline microstructure. They are rightly eliminating the possibility these structures are mineral in nature."
What is the big deal being not of mineral nature. They've already shown that the nanodes are non-mineral of nature. So it may be not stones, but it certainly has nothing in common with life.
7) "DAPI displays a specific flouresence when it binds to AT rich DNA sequences and is the best indication DNA presented in the paper but is admittedly qualitative. They did not isolate DNA for two reasons. Firstly they are a microscopy group rather than a microbiology/genetics group."
This is no argument. They could have asked anybody in their institute to provide conclusive evidence of the nature of the DNA. If they send the nanobe to me I will extract the DNA (if present).
"Secondly isolation of DNA is not always a "very simple procedure", especially when working with tissues which have never been successfully extracted before."
This is also no argument. If DNA is involved it can be extracted. The authors claim that they are able to see the nanobes-colonies by eye, thus indicating that heaps of DNA can be isolated. (By the way how do you think these nanobes synthesise their DNA?)
"The nanobes display unusual cell wall properties, grow slowly and represent a very small sample as individual colonies- all of which would impede DNA isolation."
You are mislead by the author's jargon: cell growth, cell walls, membranes, DNA etc.
"Even if the DNA tests are false positives the organisms may not contain DNA but could still be considered living. Their size is not inconsistent with a different mode of reproduction. Too much is unknown at this stage."
That would be something and I expect to read it in Nature or Science, not in the American Mineralogist.
7) "DAPI displays a specific flouresence when it binds to AT rich DNA sequences and is the best indication DNA presented in the paper but is admittedly qualitative."
And may also bind aspecifically to C-N-0 compounds. As long as the authors do not include appropriate controls I am not able to interpret their results.
"My conclusion is the same as theirs: it could be a new form of life but more research is needed."
Your conclusion is unwarranted.
Question: Why hasn't a follow up of this study been published on DNA isolation? There was ample time since 1998.
Answer: Because there is no DNA involved.
|This message is a reply to:|
| ||Message 29 by singularity, posted 07-30-2002 12:58 AM|| ||singularity has responded|