Geoscience Reference
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world to intrude on its inner spaces. This means river currents could have carried in
the finely ground and varied plant material and deposited it in the open body cavity
of this
Minmi
after it died. Therefore, these plants might not represent its final meal
after all.
Good thinking, but in my preceding description of
Minmi
and its cololite, I
omitted akeypiece ofinformation, onethat crushes that hypothesis like ankylosaur
jawswouldaCretaceousplant.Itturnsoutthisspecimenof
Minmi
wasdepositedin
a Cretaceous sea, and no river was anywhere near its body when it was laid to rest
in a shallow marine grave. Central Queensland abounds in fossils from this Creta-
ceous seaway that divided Australia then. In the same museum where I stared at the
cast of
Minmi
, hundreds of fossils of ichthyosaurs, plesiosaurs, ammonites, squid,
clams, and other sea life surrounded it, all from the same rocks.
No serious paleontologist suggests that the heavily armored ankylosaurs
paddled out to sea, just as medieval knights were not likely keen about going for
a swim in full armor. So this
Minmi
must have been a “bloat-and-float” dinosaur.
It died on land with a belly full of terrestrial plants and was filled with enough gas
from decomposition to buoy it into the ocean. Once out there, it somehow escaped
scavenging by marine carnivores; no toothmarks or other signs of nibbling were on
its body. Once it sank, it also must have made quite an impression on any sea life
living on the bottom before burial. Most amazing of all, this is an example of a di-
nosaur that carried its trace fossil with it after death and on a long journey to sea.
Dinosaur Puke
Sohowaboutfoodthatadinosaur'sgastrointestinaltractrejectedinsteadofpassing
through, or more quiescently as gastric pellets like those emitted by predatory birds
today? Tragically, examples of dinosaur regurgitalites are either extremely rare or
unrecognized from the fossil record. One regurgitalite inferred from Late Triassic
rocks contains pterosaur remains, but is thought to have come from a large fish
rather than a land-dwelling animal. I also mentioned one example interpreted in
2009, which was apparently fossilized beside the mouth of a
Coelophysis
. As much
