There isn't a single region on the planet that has an all-inclusive fossil history of life on Earth. This is why places like Big Bend National Park, which have an emphasis on one time frame, can contribute so much to our knowledge base. Big Bend National Park’s geologic history is not only complex and diverse, but also contains an amazing fossil record of the late Cretaceous and early Tertiary periods.
Some of Big Bend's fossil finds include bones of a pterosaur, the second largest known flying creature of all time with a 36-foot wingspan, as well as the skull of the triceratops-like Chasmosaurus, the largest known skull of any land animal. In addition to numerous dinosaurs, giant crocodiles, and other reptiles, the park has abundant fossilized wood, early mammals, and a wide variety of marine vertebrates and invertebrates.Information on fossil site locations are often kept confidential to protect these valuable resources.