Q: What is the difference between a dinosaur reptile and a flying pterosaur who may be a warm-blooded mammal?
A: Dinosaurs may have been warm-blooded, cold-blooded or a variety of strategies in between. Mammals have fur and nurse their live-born young. Reptiles and birds, including dinosaurs, lay eggs and don't nurse. (Don Lessem)

Q: What was the biggest flying dinosaur?
A: There were no flying dinosaurs, unless you count their descendants, birds. Dinosaurs lived only on land, not in water or air. The flying guys were pteranodons, flying reptiles. The biggest was quetzalcoatlus, 43 feet wide! That's as wide as a fighter jet airplane! (Don Lessem)

Q: Is pteranodon a real dinosaur?
A: Pteranodon was a flying reptile, not a dinosaur, though it lived in dinosaur time. Dinosaurs were a group of special reptiles that could walk with their legs directly underneath them. (Don Lessem)

Q: How did the pteranodon fly?
A: Pteranodons flew by flapping their wings and gliding. The debate is how they got up in the air — by sailing off trees and cliffs or by running and flapping. (Don Lessem)

Q: Can you help us with information about origin, eating habits and any other information about the scaphognathus crassirostris?
A: Scaphognathus crassirostris isn't a dinosaur, it is a pterosaur, or flying reptile from dinosaur times. Dinosaurs didn't fly. Its name means tub jaw, and it was one of the first pterosaurs ever found, but its fossils are very rare. It lived in Europe about 150 million years ago during the late Jurassic period and grew to a wing span of three feet, not much bigger than a crow. It probably ate fish. (Don Lessem)

A: Scaphognathus is a pterosaur, one of the flying reptiles that are first cousins to dinosaurs. Scaphognathus is one of the more primitive members of pterosauria, since it still has a long bony tail. It could probably fly pretty well and it may have eaten fish, small lizard-like animals, and small mammals. It also had good sight and a big brain that helped it to fly and navigate. Paleontologists still argue about whether pterosaurs walked on their hind legs or on all fours. Scaphognathus is a small, distant relative of quetzalcoatlus, the giant pterosaur from Texas. Pterosaurs became extinct at the end of the Cretaceous. (Tim Rowe)