Geoscience Reference
In-Depth Information
later by nearby floodwaters, or did high dives and made big splashes when exiting
their former hosts. Aquatic snails then would have been attracted to them before
their final burial and fossilization.
These Two Medicine Formation coprolites thus demonstrated the potential for
such trace fossils as a powerful means for understanding how one species of di-
nosaur—
Maiasaura peeblesorum
—could relate to its inner and outer ecosystems.
More than most other fossils from their time, they expanded our consciousness of a
LateCretaceousweboflife:gutbacteria,conifers,beetles,andsnails,allconnected
through a dinosaur.
Should I Stay or Should I Go: Dinosaur Gut Parasites
Speaking of ecosystems, individual dinosaurs harbored their own diverse micro-
floraandmicrofauna,usingtheirbodiesasplacestolive,eat,andreproduceinwhat
issometimescalleda
microbiome
.Asmostpeopleknow,everyone,humansandan-
imals alike, carry—on them or inside them—trillions of bacteria, fungi, skin mites,
and occasional harmful (pathogenic) microbial or animal parasites. Animals may
consist of lice, ticks, fleas, worms, leeches, or whatever else feels like getting a free
meal without that person or other animal host noticing it. Not all of this flora and
fauna are necessarily harmful to the host, though; for example, some gut bacteria
help to produce vitamins K and B12, and about 70% of all bacteria are harmless
to humans. Still, parasites seem to get more attention than beneficial members of
this microbiome because of the genuine harm they cause, whether through disease
transmission, psychological effects, or impurifying our precious bodily fluids.
Parasites fall into two broad categories:
endoparasites
(living inside), such
as tapeworms, and
ectoparasites
(living outside), such as ticks. Despite all we
know about parasites and how they cycle through multiple animals today, we didn't
know for sure whether dinosaurs had these as parts of their microbiomes. Instead,
parasites were just assumed for dinosaurs, especially massive sauropods, which
must have represented “The Promised Land” for many parasitic Mesozoic species.
Indeed, the main premise of
Jurassic Park
(the topic and movies) was how mos-
