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dino dna

Jeffrey Martz wrote, on 10/26/95

>> Even if someone someday comes up with a complete dinosaur DNA 
strand, this is not going to help much with dinosaur taxonmy.
Even assuming the dinosaur species of the DNA can somehow be identified, 
maybee by cloning or whatever, there will be no other dinosaur DNA strands from 
other species to compare it to.  Genetic material from extinct organisms 
isn't happened across that frequently, certainly not as frequently as 
dinosaur fossils, and no one has proven that any DNA taken from insects 
in Mesozoic amber belongs to dinosaurs as far as I know.  Osteology is 
all paleontologists have to go on to determine species as horribly 
uncertain as it may be, and unless a miricle happens it probably 
always will be.

LN Jeff <<

Genetic material from extinct organisms may not be as difficult to obtain as
you might think.  I have been successful in obtaining gene fragments from
110 MY Tenontosaurus, and 68 MY Ornithomimus, and Deinonychus, and probably
T. rex, although I have not sequenced that yet to confirm dino origin.  You
are right in the fact that DNA must come from fossil sources, and therefor
is limited by the availability of the fossils.  The older the fossil, the
less chance of getting intact DNA frags large enough to supply enough data
for analysis.  However, the resulting data will either back up the
morphological identification and stratigraphic placement of the age of the
fossil, or will contradict it, or any degree in between. This is where the
genetic data may override the morphological data. So far, my data shows that
dinos and mammals shared a commmon ancestor approx. 230 MYA, but what
happened in between has yet to be seen.  Also, my data soes not support a
cretcious theropod-modern day bird line, instead, the birds show a common
ancestral split predating the dino-mammal split by at least 40 MY.  As I get
more data, this may change, but probably not to a significant degree. The
part of the gene I am looking at is representative of the gene as a whole,
and I will attempt to amplify parts of other genes to continue to resolve
this issue.

Right now, I am getting gene fragments from about 50% of the bones I
analyse.  The bone specimens, by the way, are submitted from well known
paleontologists at well known institutes in North America, and the
identifications cannot be doubted as they are from articulated skeletons.