Today, the pinyon juniper woodlands have retreated to higher elevations and the area around the cave is dominated by desert plants. 11,000 years ago the area around Rampart Cave had a higher distribution of pinyon juniper woodlands and some desert adapted vegetation. Many of the fossil plants are still found alive in modern times but the fossils show that the distribution of these plant species differed to their modern counterparts. At present, fossils of 37 species of reptiles, birds, and mammals have been found at Rampart Cave.įossil plant evidence from sloth dung and packrat middens from inside the cave showed a rich fossil flora occurred outside. In 1942, a field team from the Smithsonian Institution did a more extensive excavation of Rampart Cave which led to the discovery of the extinct vampire bat and many other fossils. The continuous dry environment of the cave allowed for the preservation of hair and skin. The first collection from 1936 included the skin, hair, and bones of the Shasta Ground Sloth, the extinct Harrington’s mountain goat ( Oreamnos harringtoni), big horn sheep ( Ovis canadensis), an extinct horse, and a large extinct cat. It is located at the far western end of Grand Canyon National Park, near its border with Lake Mead National Recreation Area. Rampart Cave is a dry cave formed in the Redwall Limestone and was discovered in 1936. A vampire bat, Desmodus stocki, roosts in the cave ceiling while it awaits for nighttime to forage for food. A Shasta Ground Sloth, Nothrotheriops shastensis, is entering the cave and the ground is carpeted with its large droppings. The 2019 National Fossil Day artwork depicts the entrance of Rampart Cave 11,000 years ago. Rampart Cave: An Ice Age Tomb of the American Southwest One of the best Pleistocene cave sites in the Grand Canyon, Rampart Cave, is the focus of the 2019 National Fossil Day Artwork. Fossils of Pleistocene plants and animals have been found in caves and crevices sites along the full length of the Grand Canyon. These fossils are from the late Pleistocene Epoch (40 thousand to 10 thousand years ago) and show evidence of a different Grand Canyon than what we see today. Though there is a rich fossil history from the Paleozoic Era at the Grand Canyon, some of the most well-studied fossils from this National Park come from the end of the Cenozoic Era (66 million years to today). The border corners of the 2019 National Fossil Day artwork shows some notable Paleozoic fossils from Grand Canyon National Park: a trilobite from the Cambrian Bright Angel Shale a fern from the Hermit Formation a footprint of Chelichnus, a mammal-like reptile from the Coconino Sandstone and the large tooth of Megactenopetalus, a shark from the Kaibab Limestone. Paleozoic fossils from the Grand Canyon include some of the oldest evidence of invertebrate animals, ancient plants, early reptiles, and ancient fish. The youngest Paleozoic fossils are 260 million years in age (Permian Period). The oldest of these fossils are approximately 540 million years in age (Cambrian Period). The majority of the fossil-bearing rocks of the Grand Canyon represent the Paleozoic Era. Many of these layers hold rich fossil records. Over millions of years, the Colorado River and its tributaries have carved the canyon, cutting through geologic layers revealing the pages of deep time. The Grand Canyon also inspired previous presidents such as Benjamin Harrison and Theodore Roosevelt, both of whom worked to preserve this land during their administrations. The 2019 logo artwork honors the 100th anniversary of the establishment of the Grand Canyon National Park, which occurred on February 26th, 1919 by President Woodrow Wilson. The majesty of the Grand Canyon has long inspired adventurers, artists, scientists, and other visitors. Grand Canyon National Park: 100 Years of Fossil Discovery
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