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Re: The validity of cladograms (was Re: giant birds)



Chris Brochu wrote:
> Also - on what basis do you regard DNA tests as "more reliable?"

Well, there are more features to compare with DNA tests than there are with
bone tests - on the order of millions of base pairs in the former, as
opposed to the (comparatively) mere thousands of features you get in the
latter.  That's just with modern bone tests.  With fossils you also have the
problem of random bones being missing.  Dinogeorge mentioned doing an
only-skull analyses.  I wonder how accurate the sauropod branch of that
would be given there are few sauropod heads.  Not only bones missing, but
entire species - In essence, the material included in your test was picked
for you with it's own preservation bias agenda.  That's gotta throw out the
results by some.  My knowledge on ancient DNA is probably more fragmentary
than the material in question, so I won't comment on that.  So in summary I
will say that I regard DNA tests more reliable because of the DNA, not
because of the test.

Out of curiosity, are there any organisations like Genbank
http://helix.nih.gov/science/genbank.html  set up for researchers doing
cladistic trees using bone material?  If not, why not?

Yours sincerely,
                         Samuel Barnett