One of the staff paleontologists explained that although the bones
due undergo some mineralization due to water penetrating the very
porous surfaces they are in fact, bone.
The bones of Sue the T-Rex are so well preserved in fact that there
is hope to recover DNA from fossilized marrow. (this has already
been accomplished other places with other specimens).
Chicago may get a little too cold for a Jurrasic park.... ;)
Another interesting point for EVMick, the histology (structure) of
dinosaur bones is between that of large mammals and birds, in other
words they are more porous especially toward the outer third of the
bone and therefore considerably less dense that those of modern
mammals.
It is also believed by some that they were muscled more like birds
rather than mammals, being lighter still.
Others have already pointed out the "range" argument. Some wooly
mammoths survived till about 7 thousand years ago on and island off
Siberia as I recall, but due to the decreased range, they shrunk
till they were 4-5' high. Interesting.
Brian
Member,Extropy Institute
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