Pterosaurs were the first flying vertebrates (animals with backbones) in evolutionary history. The smallest species was sparrow-sized and the largest was as tall as a giraffe (Quetzalcoatlus northropi). Pterosaurs were winged, flying reptiles which lived alongside dinosaurs, and are a distinct order within the scientific classification system Pterosauria. Pterodactyls are the most commonly referenced species, and are often considered to be “flying dinosaurs” which is scientifically false. Pterodactyl refers only to members of the Pterodactylus genus, while there are over 150 genera of pterosaurs known at this time. 

The wings of pterosaurs were not thin membranes of skin, but instead made up of individual fibers called actinofibrils. These fibers were able to shift with the changing air currents. Additionally, pterosaurs had hollow bones (like birds) and air sacs which lessened their weight and increased metabolism. Some species even showed evidence of furry filaments, or pycnofibers, covering their bodies, which suggest warm-bloodedness. Habitats were varied, with evidence of pterosaurs living in many environments, from beaches and deltas to forests, plains and mountains. Their eating habits were similarly varied and matched their habitats, and included fruit-eaters, fish-eaters, filter-feeders and even terrestrial stalkers with skulls longer than a human is tall.