Geoscience Reference
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break wood, but swallowed it. So one solution that neatly explained such wholesale
consumption of woody tissues is that these dinosaurs were eating large volumes of
this decomposing wood for the insects (and perhaps some fungi). These caring di-
nosaur parents then transported these MREs (meals-ready-to-eat) in their stomachs
backtotheirnests,wheretheyobliginglyregurgitatedthemintothewaitingmouths
of their hatchlings. Admittedly, this is a difficult hypothesis to test more directly,
unless paleontologists some day find juvenile
Maiasaura
skeletons with enterolites
matching the content of the adult's coprolites.
What more could be learned from these coprolites, the gifts that kept on giv-
ing? It turned out that Cretaceous dung beetles were not the only ones taking ad-
vantageofbountifulsuppliesofnutritiousdinosaurdung:snailsgotintotheact,too.
I remember these gastropods surprising me in 2009 while on a field trip with about
thirty other paleontologists, led by Dave Varricchio, Frankie Jackson, and Jack
Horner. Most participants would have admitted that the
Maiasaura
and
Troodon
nest sites were the main draw of the field trip for them. Yet I was equally excited
to know that we would also be strolling through the same area with the hadrosaur
coprolitesIhadseennineyearsbeforewhenstudyingfossilinsectcocoonsandbur-
rows there. Would I notice anything different about the coprolites this time?
Well, yes. The coprolites, just like before, were easy to spot in the field area,
sticking out on the eroded surface of the Two Medicine Formation as dark, base-
ball-tosoccer-ball-sizedlumps.Althoughsomeofushadseenthembefore,thisdid
notdimourenthusiasm andweall stoppedtomarvel athowthese formerly squishy
vestiges had survived long enough for us to witness them, at that moment, now
hard as rock. Sure enough, the finely broken and blackened wood chips of Creta-
ceous conifers were held together by whitish calcite cement. A few even had cir-
cular outlines or lengthwise sections of burrows, the right size to have belonged to
dung beetles. We were in awe. Still, as is typical with coprolites, bathroom humor
quickly overtook lofty ideals and higher cognitive functions. Within minutes, we
