Age of Mammals: The Cenozoic Era

Carnegie Museum of Natural History’s exhibition hall about the Cenozoic Era will reopen this month with a new look, new features, and new scientific information.

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irish elkAge of Mammals: The Cenozoic Era presents fossils of animals that lived during the last 66 million years of Earth history, which is known as the Cenozoic Era, or Age of Mammals. Although mammals first evolved early in the Mesozoic Era (the Age of Dinosaurs), they diversified greatly during the Cenozoic, after the extinction of dinosaurs had dramatically modified the character of many of Earth’s habitats.

The most recent 2.6 million years of the Cenozoic is known as the Pleistocene Epoch, commonly called the Ice Age. During this interval enormous glaciers moved over large areas of the northern continents, changing climatic conditions and strongly impacting plant and animal evolution and distribution.

Exhibition Highlights

Cenozoic Hall Mammoth Age of Mammals: The Cenozoic Era documents some of the evolutionary history of mammals during the past 66 million years and emphasizes many of the strengths of Carnegie Museum of Natural History’s paleontological collection. Especially noteworthy are specimens collected from what is now Agate Fossil Beds National Monument in western Nebraska. Between 1900 and 1908, Carnegie Museum paleontologists made a large collection of approximately 20 million-year-old mammal fossils from this region. Specimens on view in Age of Mammals: The Cenozoic Era include exquisite skeletons of the bizarre, horse-like Moropus and the formidable warthog-like creature Dinohyus, an amazingly dense ‘bone bed’ composed mostly of remains of the ancient rhino Menoceras, and a grouping of three oreodonts (extinct hoofed mammals) that perished in a sandstorm and are preserved exactly as they died. Other exhibits illustrate anatomical changes through time, including those that occurred during the 55 million-year evolutionary history of the horse.

The Pleistocene area of Age of Mammals: The Cenozoic Era features several well-known Ice Age species, including a fossil skeleton of a Columbian mammoth from Milliken, Colorado, and skeletons of a saber-toothed cat, dire wolf, and giant ground sloth from the famous Rancho La Brea tar pits of California. Also on exhibit are skeletons of a moa (a giant flightless bird from New Zealand) and an Irish elk.