Siegfried Family Hall of Ancient Life

The Hall of Ancient Life takes you on a tour of Oklahoma’s deep past in a series of exhibits featuring some of the most impressive specimens in the museum’s extensive paleontology collections.

The exhibits begin with the fossils of trilobites and other invertebrates that appeared in the ancient seas covering Oklahoma about 500 million years ago. You will see examples of the “mammal-like” reptiles and other animals that preceded the dinosaurs, and experience the Age of the Dinosaurs during the Mesozoic era, 248 to 65 million years ago, through a breathtaking series of dioramas featuring some of the largest dinosaurs in the world. Finally, you will learn about mass extinction events such as the one that wiped out all of the dinosaurs except birds, and see fossils of the mammals that came afterward.

When you leave this gallery, be sure to take a ride in the “dinovator” – a glass elevator that takes you up 26 feet to see the museum’s mighty Apatosaurus eye to eye.

PALEOZOIC ERA 542 to 251 million years ago

During much of this time, the land that is now Oklahoma was covered by the warm and shallow waters of ancient seas. In these exhibits, you will see the remains of animals that inhabited these seas from the Cambrian Period through the Upper Carboniferous Period – 542 to 299 million years ago, and the plants that dominated the great coal swamps of the Upper Carboniferous. You will also encounter some of the vertebrates that lived in Oklahoma during the Permian Period, 286 to 251 million years ago. These include primative synapsids, or “mammal-like reptiles” – those which would eventually evolve, over the next several million years, into mammals.

MESOZOIC ERA 251 to 65 million years ago

Mesozoic rocks preserve many “firsts”—the first dinosaur fossils, the first mammal fossils, the first fossils of flying vertebrates and the first flowering plant fossils.

The Mesozoic is sometimes referred to as the Age of Dinosaurs because it was the time in which dinosaurs first evolved, diversified and rose to dominate the globe. However, this era also saw the development of the first mammals. Though mostly small plant- or insect-eaters living in the shadow of the dinosaurs during this time, mammals would eventually claim the earth as their own.

In addition to the dinosaurs, a number of other animals also populated the earth during the Mesozoic. The oceans were home to swimming reptiles such as plesiosaurs and mosasaurs, as well as invertebrates like the ammonites. Pterosaurs, extinct flying reptiles and early birds – flying dinosaurs – filled the skies. The Mesozoic exhibits are divided into three periods: the Triassic, the Jurassic and the Cretaceous.

CENOZOIC ERA 65 million years ago to the present

After the extinctions at the end of the Cretaceous, mammals rose to dominate the landscape. During this time, the animals that populated Oklahoma were very different from those we see today. Cenozoic exhibits include examples of Smilodon, the Saber-toothed cat; the enormous short-faced bear Arctodus; and the pony-sized camel Procamelus. The ice age began in the Pliocene Epoch, around 2.5 to 3.5 million years ago. Toward the end of the Neogene, around 10,000 years ago, most of the larger animals became extinct.

Humans also appeared in Oklahoma during this time, between 30,000 and 15,000 years ago.