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ceratopsian behaved. What was it doing 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 dinosaur going on all fours was—you guessed it— facultatively quadrupedal . These changes inwhich limbs touched the ground were likely related to dinosaurs altering their speed, foraging, or other such behavioral shifts necessitated by daily life.
    Every four-limbed animal has a baseline gait, or how it normally moves around on those limbs. In quadrupedal animals, such as canines, felines, bovines, or other domestic mammals, a few examples of gaits include: slow walking, normal (average) 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 is a very handy one to identify quickly, especially in a remote field area.) We also can get a better understanding of gaits by measuring distances between alternating feet ( pace ), between the same foot ( stride ), and the width of the trackway ( straddle ). Many other measurements can be taken from a trackway, but these three are essential and constitute a good start in their study.
    Can these same principles be applied to dinosaur trackways, in which you can just glance at a dinosaur trackway and excitedly shout “Theropod!” “Ornithopod!” or “Barney!” (whatever the heck he is)? The answer is, mostly, yes. Part of this identification is aided by the obviousness of some tracks, which are then confirmed by trackway patterns. For example, if you see bathtub-sized depressions that express themselves in an alternating diagonal pattern, you will probably not shout “Baby theropod!” Furthermore, sauropod tracks normally show a slow walking or “understep” pattern in which the rear foot did not quite fall in the same place as the front foot; appropriately, its stride is short, too. In a few instances, their rear tracks registered directly on top of (and hence wiped out)their front tracks, indicating a slightly less sluggish pace. So far, I have only seen one sauropod trackway in which the rear feet were placed ahead of the front feet on the same side, approaching what we might call a “trot.” This trackway was from a relatively small sauropod, which might have been a juvenile that didn’t know it