FROM THE EDUCATION DESK
December Trivia: December was originally the 10th month in the Roman calendar. The Roman calendar was based on a 304 day year. In December of 1790 the US Congress moved from New York to Philadelphia and on December of 1877 Thomas Edison demonstrated the first sound recording. He recited “Mary had a Little Lamb” in his New Jersey laboratory.
Some were gigantic while others could fit in the palm of a hand:
Millions of years ago, the skies were ruled by pterosaurs, the first animals with backbones to fly under their own power.
Pterosaurs have incredible diversity. For more than 100 million years in the history of life on Earth, the only animals that truly flew, not just glided, were insects. Around the time that dinosaurs arose, the first pterosaurs appeared in the sky…the age of flying reptiles was here. They are close cousins of dinosaurs who evolved on a separate branch of the reptile family tree.
Scientists have long debated where pterosaurs fit on the evolutionary tree.
Some were as large as an F-16 fighter jet, and others as small as a paper airplane. Some were small, had long tails and sturdy bodies. Others had long, slender jaws, elaborate head crests, specialized teeth and were very large. Many pterosaur species lived along oceans and lakes, probably diving to catch fish or other sea animals as they soared over the water. Others may have walked through shallow waters looking for shellfish.
Few pterosaurs lived close to the places where fossils tend to form. Their fragile bones preserved poorly, so their fossils are frequently incomplete. The bones often drifted apart, shattered, or became scrambled before they could be preserved. The fossils are easily damaged when transported or prepared for study or display.
Preondactylus buffarinii, found near Preone, a village in the Italian Alps, is one of the oldest pterosaurs, dating back around 220 million years. The most complete specimen discovered so far broke into several pieces when it was removed from the surrounding rock, and most of the brittle skeleton was lost. All that remains are small fragments and an imprint of the rest of the bones.
An adult pterosaur, Anhanguera sanyanae, was discovered as a three-dimensional fossil so well preserved because it was protected inside a hard shell, called a nodule. This animal’s body was buried by fine sediments, which slowed down decomposition and allowed fossilization to begin. As the mud gradually settled, a hard shell formed around the remains and protected them.
Like other flying animals, pterosaurs generated lift with their wings. They needed to perform the same kinds of motions as birds and bats, but their wings evolved independently, developing their own distinct aerodynamic structure. Their wing bones were hollow tubes, with walls no thicker than a playing card. Like bird bones, they were flexible and lightweight with veins and arteries which kept the wings nourished with blood.
Pterosaurs were an extremely successful group of reptiles which lasted all through the age of dinosaurs, a period of more than 150 million years. They left no descendants.
“Good things are coming down the road…just don’t stop walking”