It’s disconcerting that the article ( http://m.wired.com/wiredscience/2010/12/denisovans/ ) opens up talking about a finger bone, but displays a photo of a tooth.
> However, kinetic calculations predict that
> small fragments of DNA (100–500 bp) will survive for no
> more than 10 kyr in temperate regions and for a maximum
> of 100 kyr at colder latitudes owing to hydrolytic damage
> (Poinar et al. 1996; Smith et al. 2001). Even under ideal
> conditions, amplifiable DNA is not thought to survive for
> longer than 1 Myr.
> http://rspb.royalsocietypublishing.org/content/272/1558/3.full.pdf+html?sid=1c
> ad9280-7246-49eb-b212-6f6358028c5e
This article discusses the viability of DNA over long periods of time. It finds that DNA in dead organisms degenerates over time, so that what appears to be indicating DNA of a different species may in fact simply be the product of postmortem degeneration. It’s also interesting to see that identifiable fragments of DNA would not be expected to survive over 10,000 years in a temperate region (where this part of Siberia is located). These findings fit much better with the biblical creation scenario than with the 40,000 years mentioned in the wired.com article.
Much of the rest of the article is conjecture based on interpreting evidence from an evolutionary perspective. I wonder how these scientists are defining ‘species’, since they acknowledge that these early humans probably interbred with other human populations. It would make more sense to describe these people as a different strain or variety, like the Australian aborigines or Eskimos—assuming that the DNA differences found aren’t simply the result of postmortem degeneration over time.
Susan
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