Geoscience Reference
In-Depth Information
• Thousands of trackways of the “cleanup” crew, such as insects specialized
at eating dinosaur throw-up. Just as there are insects that specialize in eat-
ing dinosaur poop, there may have been some that enjoyed a pre-digested
(but totally vegan) meal.
Only one instance of fossilized dinosaur vomit, containing a mix of dinosaur
and turtle bones in Early Cretaceous rocks of Mongolia, is inferred to have come
from an actual dinosaur. Another possible dinosaurian up-chuck is embodied in a
mass of four birds from the Early Cretaceous of Spain. However, the paleontolo-
gists reporting it thought it also may have been from a pterosaur. Otherwise, most
Mesozoic regurgitalites are credited to marine-reptile contemporaries of dinosaurs:
ichthyosaurs. These deposits, found in Late Jurassic rocks of the U.K., consist of
concentrated collections of belemnite shells. Belemnites, which were squid-like an-
imals that shared the seas with ichthyosaurs, also show up as stomach contents.
However, these masses of cigar-shaped shells were found by themselves and were
acid-etched. This suggested they spent time bathed in low-pH stomach acids, but
becausetheywerenotinsideanichthyosaurskeleton,theywereeitherregurgitalites
or coprolites.
Coprolites were quickly eliminated as an explanation, though, because belem-
niteshellsarepointyononeend.Nowimaginebeinganichthyosaurthatswallowed
several dozen pointy-ended shells and passed those out its other end: no, thanks.
The risk of internal injury also would have been too high to pass such shells all the
waythroughintestines toosensitive tohandle suchapayload. Hence these werethe
marine version of gastric pellets, in which ichthyosaurs snapped up lots of belem-
nites, kept them down long enough to digest their useful nutrients from the soft
parts, and then coughed up their shells.
Other than gastric pellets or illness, what would have been other reasons for a
dinosaur to barf? One would have been from the desire to feed their children warm
meals. And if it were regurgitated as meals for hungry youngsters and puked right
intotheirwaitinglittlemouths,atraceofthisinthefossilrecordwouldbeveryrare
