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in the place where it left its tracks? When did it arrive on the scene relative to other
dinosaurs, insects, or worms living in the same area? Where did it go after it made
the tracks? Could its body be nearby, or did it travel a long way before dying? Was
it with any others of its species, or looking for love in all the wrong places? How
long were these tracks there before they were buried and preserved for us to see
them millions of years later? You want to know more. Much, much more.
To understand dinosaur behavior from their tracks, one must absolutely study
sequences of tracks, or
trackways
. Knowing that most dinosaurs either got around
quadrupedally or bipedally, trackways therefore can be expected to show right-left
rear foot impressions or a combination of all four feet. However, a few dinosaurs
mixed it up, switching from bipedal to quadrupedal and back again, just like how
someone can go from walking upright while filled with pride to crawling on hands
and knees begging for forgiveness to walking tall again. In a dinosaurian sense,
though, a change from a four-legged to a two-legged gait meant that a dinosaur was
facultatively bipedal
(became bipedal when it wanted) and a normally two-legged
dinosaurgoingonallfourswas—youguessedit—
facultatively quadrupedal
.These
changesinwhichlimbstouchedthegroundwerelikelyrelated todinosaursaltering
their speed, foraging, or other such behavioral shifts necessitated by daily life.
Everyfour-limbedanimalhasabaselinegait,orhowitnormallymovesaround
on those limbs. In quadrupedal animals, such as canines, felines, bovines, or other
domestic mammals, a few examples of gaits include: slow walking, normal (aver-
age) walking, fast walking, trot, lope, or gallop. For example, cats normally walk
and dogs normally trot. When teaching these patterns to my students, I emphasize
how gaits translate into distinctive track patterns, much like letters put together to
form words. In these instances, trackway patterns read as “slow walk,” “fast walk,”
“trot,” and so on. Once these students apply this knowledge to different animals'
baseline gaits, they then can more readily glance at and discern a trackway pattern,
rather than stopping to measure track sizes and count toes, and much later saying
“raccoon,” “coyote,” “deer,” or “grizzly bear.” (In my experience, the last of these
