Quetzalcoatlus is a genus of large pterosaur that lived during the Late Cretaceous in what is now North America. Quetzalcoatlus is thought to have been one of the largest pterosaurs to have ever roamed the earth. The size of quetzalcoatlus brought up a question: How could this creature get airborne. Quetzalcoatlus would have stood with its four limbs on the ground, then lean back, and finally, it would push itself foreword and into the air.