70 million years ago, dinosaurs roamed the park while unknowingly leaving clues of their lives for us to uncover. Today, a selection of Denali's fossils are on display at the Murie Science and Learning Center, where you can view and touch them in person. If you aren't in the park you can also check them out in 3D by exploring the links below.
We created these three-dimensional (3D) models with a technique called Structure from Motion (SfM). SfM builds 3D models using two-dimensional photos and their orientation relative to each other. We photographed each fossil from multiple angles to capture all of their different surfaces, then stitched the photos together using algorithm-driven computer software. Hadrosaurs, also known as duck-billed dinosaurs for their flat snouts, were large herbivores that roamed Denali in herds that included family groups. This behavior is captured at one fossil site in the park that shows thousands of juvenile- to adult-sized hadrosaur tracks walking across a sports-field-sized surface. Isolated tracks are also found throughout the Cantwell Formation. Some are even covered in plant fossils.
Rare, four-toed tracks of therizinosaurs found in the park are the northernmost known occurrence of this type of dinosaur. These odd, feather-covered, sickle-clawed, pot-bellied dinosaurs are theropods, most of which are bipedal meat eaters. However, therizinosaurs are believed to have been herbivorous based on tooth, jaw, and abdominal characteristics.
The top predators in ancient Denali were all theropods. Several different types of these bipedal carnivores left their tracks in the Cantwell sediments. The first dinosaur track ever found in Denali was spotted in 2005 and is a type of small unidentified theropod.
The Cantwell Formation preserves one of the most diverse assemblage of bird tracks in the world, suggesting that many different species of birds made Denali their home during the Cretaceous. Tracks from sparrow- to heron-sized birds have been found, sometimes with feeding traces where birds poked their beaks into the mud.
Equisetum, commonly called horsetail, is a common fossil plant in the Cantwell Formation. Equisetum still thrives in Denali today, and is considered to be a ‘living fossil’. It is the only remaining genus in the entire class Equisetopsida, which has survived in marshy areas for 400 million years.
The fossil plants found in the Cantwell Formation are the remains of an ancient forest that used to live in Denali National Park. Metasequoia trees, a type of redwood, towered above the lush green ferns, shrubs, ginkgoes, and cycads of the forest understory, and were used as a ladder to the sun by vines. Leaf fossils from flowering plants can be used to estimate that the ancient climate was like. There is an observed correlation between temperature and precipitation, and leaf characteristics in modern climates that can be applied to fossil leaves.
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Last updated: June 29, 2016