The Hall of Vertebrate Origins tells the story of the burgeoning of vertebrates through the oceans and onto land, an evolutionary sequence stretching back more than 500 million years. The development of some of the most basic, yet revolutionary, physical characteristics—the backbone, jaws, limbs, and the ability to reproduce without returning to the water—was key to the evolution of life on Earth and is examined in the Hall of Vertebrate Origins. The Hall traces the evolution of such stunningly varied creatures as the first vertebrates to walk on land, the first vertebrates to live entirely on land, and the first flying vertebrates. Highlights include Buettneria, one of the earliest four-limbed animals; the massive armored early fish Dunkleosteus; the gigantic aquatic turtle known as Stupendemys; and Pteranodon, a flying reptile, or pterosaur, with a wingspan of 23 feet.