Feathered dinosaur is possible that feathers first developed in an even earlier group, in light of the discovery of pycnofibers of pterosaurs. Crocodilians also possess beta keratin similar to those of birds, which suggests that they evolved from common ancestral genes. Shortly after the 1859 publication of Charles Darwin's "On the Origin of Species", British biologist Thomas Henry Huxley proposed that birds were descendants of dinosaurs. He compared the skeletal structure of "Compsognathus", a small theropod dinosaur, and the 'first bird' "Archaeopteryx lithographica" (both of which were found in the Upper Jurassic Bavarian limestone of Solnhofen). He showed that, apart from its
Ruppert Archaeopteryx Ruppert Archaeopteryx The Ruppert Archaeopteryx () is a Swiss high-wing, pod-and-boom, single-seat, microlift glider that was designed by Roger Ruppert and is produced by Ruppert Composite GmbH. The aircraft is named for the feathered Archaeopteryx dinosaur. The Archaeopteryx was conceived as a foot-launchable microlift sailplane, with the design goals of a light empty weight, low stall speed with gentle stall characteristics, good maneuverability and good high speed performance. A further goal was a sailplane that could be foot-launched in zero wind conditions. The Archaeopteryx design started in 1998 at the Zurich University of Applied Sciences (ZHW) as a research project.