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Re: Dino-fuzz found in amber?

Am 16.09.2011 03:35, schrieb Roberto Takata:


 Not in amber: New evidence for 250 Ma age of halotolerant bacterium
 from a Permian salt crystal "These results support the 250 Ma age of
 the fluid inclusions, and by inference, the long-term survivability
 of microorganisms such as Virgibacillus sp. 2–9-3."
 http://geology.gsapubs.org/content/33/4/265.abstract
Those are supposed to be _living_ bacteria which kept repairing their DNA all the time. 


 S. O. Rogers, K. Langenegger and O. Holdenrieder
Again you didn't cite the year. Papers are cited by author and year, and only then by title, journal, volume number and page numbers. 

The year is 2000. That's long ago.


 DNA Changes in Tissues Entrapped in Plant Resins (the Precursors of
 Amber) "There have been many reports characterizing DNA from amber,
 which is a fossil version of plant resin. Here we report an
 investigation of the effects of plant resin (from Pseudotsuga
 menziesii) and drying conditions on the preservation of DNA in
 biological tissues. We examined the degree of degradation of the DNA
 by agarose gel electrophoresis of extracted DNA, by polymerase chain
 reaction, and by DNA sequencing. The plant resin alone appeared to
 cause little or no damage to DNA. Tissue immersed in plant resin that
 dried rapidly (exposed to sunlight) contained DNA with little
 apparent damage. Tissue immersed in the resin that was dried slowly
 (in shade without sunlight) contained DNA with some degradation (3.5%
 nucleotide changes). The tissue that was immersed in the resin that
 was constantly hydrated (by immersion in water) yielded DNA that was
 severely damaged (50–62% nucleotide changes). Transversions
 outnumbered transitions in these samples by a ratio of 1.4 : 1. A
 piece of Baltic amber immersed in water for 5 days appeared to be
 impervious to the water. Thus amber inclusions that initially dried
 rapidly have the potential to yield undamaged DNA. Those that dried
 slowly may contain damaged DNA and may be unsuitable for
 phylogenetic and other studies."
 http://www.springerlink.com/content/nkwfnx34fhatgw21/
Sounds good, indeed promising, but tells us nothing about whether DNA survives under waterproof conditions for years or millions of years. 


 And there are advances in the paleogenetic techniques:
 http://www.sciencedirect.com/science/article/pii/S0169534708001602
That's from 2008, so they really are advances. Well, they mean it's now possible to make use of more and more degraded DNA, but when there's no DNA left, they can't do anything either. 


 All in all it still seems to me that try to get DNA from those
 protofeathers would be interesting.
Sure, but I bet it would yield nothing... and so, I'm sure, would any funding agency.