Dinosaur activity in the region stretches back at least 50 million years earlier than most people imagine, during the Late Triassic and Lower Jurassic periods. Evidence of these ancient creatures can be found within the Glen Canyon Group, a collection of rock formations that bear witness to the arid, sandy desert environments of the time. One of the most famous of these formations is the Navajo Sandstone, celebrated not only for its fossilized sand dunes on display at Arches National Park but also for its cultural significance—named in honor of the Navajo people and their sacred mountains. This striking formation provides a window into prehistoric desert landscapes, long before humans ever walked these lands. Equally significant is the Kayenta Formation, named after the culturally rich Kayenta region, which also contains important clues about the dinosaurs that once roamed these lands. Near Kanab, Utah, Native American pictographs tell a story of these ancient times, depicting large, three-toed tracks beside actual dinosaur tracksites. These tracks, known as Eubrontes—which translates to "true thunder"—are a vivid reminder of the power and presence of these prehistoric creatures. Measuring between 12 and 18 inches (30 to 45 cm), these prints were left by carnivorous theropods, large predators that reached lengths of up to 16 feet (5 meters). As their thunderous footfalls echoed across the desert, they may have inspired later generations to associate them with mythical creatures like the Brontosaurus—whose name fittingly means "thunder lizard." Eubrontes tracks, first identified in the Lower Jurassic rock layers of New England in the mid-1800s, hold significance across the United States. In fact, these tracks are now recognized as the official state fossil of Connecticut. This widespread presence of large theropods in both the east and west during this era suggests they were dominant predators in multiple environments, from desert expanses to areas that once contained lakes and ponds. Alongside these large tracks, smaller ones named Grallator, typically only 3 to 6 inches (10 to 15 cm) long, reveal a more modest presence—turkey-sized theropods that were abundant during the Late Triassic and continued to thrive through the Jurassic. In early New England, colonists even referred to these diminutive prints as Noah's Raven tracks, highlighting the mysterious allure they held in early America. Despite the prominence of these carnivores, herbivorous dinosaur tracks and remains are surprisingly rare. However, one standout among these vegetarian giants is Otozoum, meaning "giant animal." These tracks, left by an ancestor of the massive sauropods, showcase the presence of plant-eating dinosaurs up to 16 feet long. Remarkably, the first western discovery of Otozoum was made in Moab in 1990, shedding new light on the region’s herbivorous inhabitants. Another rare discovery came in the form of Anomoepus moabensis—a small, 2-inch long track discovered along Potash Road. It may represent another herbivore, providing further clues about the delicate balance between carnivores and herbivores in these early ecosystems. Interestingly, the Early Jurassic desert wasn’t solely dominated by dinosaurs. Tracks of small upright-walking crocodile relatives, such as Batrachopus, suggest that these ancient crocs were also fierce predators. Unlike their modern, sprawling descendants, these early crocs walked upright and competed with theropods for food. However, a lingering question remains: what did all these predators eat when herbivorous dinosaurs were scarce? Paleontologists speculate that carnivores may have preyed upon each other, establishing a complex and potentially violent desert ecosystem dominated by hungry predators. While the presence of so many predatory dinosaurs is fascinating, smaller creatures also thrived in this environment. Fossilized dune surfaces reveal traces of cat-sized mammals, crow-sized theropods, and even ancient spiders and scorpions. Meanwhile, tracks of larger theropods (**Eubrontes**), sauropod ancestors (**Otozoum**), and small crocs (**Batrachopus**) are commonly found near ancient ponds and watercourses, suggesting that life flourished wherever water was present, despite the harsh desert conditions. The discovery of these dinosaur tracks in the arid environments around Moab continues to surprise and intrigue paleontologists. Today, visitors and students have the opportunity to step back in time and follow in the literal footsteps of these ancient giants. If you're intrigued, join Appleseed Expeditions on a school trip to Moab, where students will explore the rich history of dinosaurs, learn about native cultures, and uncover the stories behind ancient petroglyphs carved into the desert landscape. It's a journey through time, from prehistoric life to the early inhabitants who revered this land.
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