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did it die somewhere else and was later placed in the burrow, whether by river cur-
rents or a predator that used the hole as a cache?
Dave shared a few of these thoughts with the rest of the field crew at the time,
and once the specimen was jacketed and detached from the earth, they carried it out
on a stretcher, a victim of Cretaceous circumstances undergoing its last journey. He
andeveryoneelsethenhadtowaitfortheskeletontobepreparedattheMuseumof
the Rockies in Bozeman, with the hope that its bones would tell Dave more secrets.
However, before this specimen was separated from its entombing sediment
in a preparatory lab, Dave had used me—in an intellectually sordid way, I might
add—to test his hypothesis. His exclusion of much information about the find, such
as its age, location, interpretation of the original environment, and the oh-so-minor
detail that it involved a dinosaur, was purposeful and sneakily effective. Still, it re-
duced the possibility of bias in my assessing the photo and ensured that I would
interpret it solely on its face value as a possible trace fossil and not as something I
was hoping to see.
Once in Lima, Dave had prearranged a meeting with a friend and his wife who
were passing through Montana that week. Both were non-geologically inclined but
able-bodied and eager to help us, so the four of us went to the field area. Like many
dinosaurdiscoverysitesinthewesternU.S.,gettingthereinvolvedgettingoffpave-
ment and going down a dirt road, with cow pastures on either side. Once on U.S.
Forest Service land, we parked, unloaded shovels, picks, and other human-powered
earth-moving tools from Dave's car, and began walking across a sparsely grassed
expanse with rolling hillocks and minor gullies.
I scanned the ground as we traveled, looking for pieces of sandstone weather-
ing out of the mostly weathered mudstone bedrock in the area, stopping to pick up
and look at the more interesting samples. Some of these sandstone bits contained
small holes that led to longer tubes, which I recognized as burrows. These trace
fossilsweremadebyinvertebrateanimals—probablyinsects—livingwiththedino-
saurs in this area about 95 mya . Other than these ichnologically motivated pauses,
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