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Re: Dino-fuzz found in amber?



Another case of "old" ancientDNA (but not from amber):
Eske Willerslev et al. 2003: Diverse Plant and Animal Genetic Records from
Holocene and Pleistocene Sediments. Science 300 (5620): 791–5.
"Genetic analyses of permafrost and temperate sediments reveal that plant and
animal DNA may be preserved for long periods, even in the absence of obvious
macrofossils. In Siberia, five permafrost cores ranging from 400,000 to 10,000
years old contained at least 19 different plant taxa, including the oldest
authenticated ancient DNA sequences known, and megafaunal sequences including
mammoth, bison, and horse. The genetic data record a number of dramatic
changes in the taxonomic diversity and composition of Beringian vegetation and
fauna. Temperate cave sediments in New Zealand also yielded DNA sequences of
extinct biota, including two species of ratite moa, and 29 plant taxa
characteristic of the prehuman environment. Therefore, many sedimentary
deposits may contain unique, and widespread, genetic records of
paleoenvironments."

but see also:
Jeremy J. Austin et al. 1997: Problems of reproducibility – does geologically
ancient DNA survive in amber–preserved insects? Proc. R. Soc. Lond. B
264(1381): 467-474.
"Apparently ancient DNA has been reported from amber–preserved insects many
millions of years old. Rigorous attempts to reproduce these DNA sequences from
amber– and copal–preserved bees and flies have failed to detect any authentic
ancient insect DNA. Lack of reproducibility suggests that DNA does not survive
over millions of years even in amber, the most promising of fossil
environments."

Best regards,
Alex

Roberto Takata schrieb am 2011-09-16:
> R DeSalle, J Gatesy, W Wheeler and D Grimaldi
> DNA sequences from a fossil termite in Oligo-Miocene amber and their
> phylogenetic implications
> "ABSTRACT
> DNA was extracted from the fossil termite Mastotermes
> electrodominicus
> preserved in Oligo-Miocene amber (25 million to 30 million years
> old).
> Fragments of mitochondrial [16S ribosomal DNA (rDNA)] and nuclear
> (18S
> rDNA) genes were amplified by polymerase chain reaction. Phylogenetic
> analysis of fossil and extant 18S rDNA confirmed morphological
> cladistic analyses of living dictyopterans (termites, cockroaches,
> and
> mantids). The fossil termite shares several sequence attributes with
> Mastotermes darwiniensis. Addition of this fossil to living-species
> phylogeny is required to substantiate Mastotermes monophyly and
> affects molecular phylogenetic hypotheses of termites in this, the
> oldest DNA yet characterized."
> http://www.sciencemag.org/content/257/5078/1933.short
> ------------

> []s,

> Roberto Takata

> On Thu, Sep 15, 2011 at 3:45 PM, David Marjanovic
> <david.marjanovic@gmx.at> wrote:
> > As far as known today, DNA doesn't last longer than 100,000 years,
> > unless
> > it's frozen, and the only place that _might_ have stayed frozen
> > since the
> > Mesozoic are the Gamburtsev Mountains in Antarctica. I hear they're
> > currently covered by 1 to 2 miles of ice.