Bird display both clearly traditional reptilian characteristics: teeth, clawed fingers, and a long, lizard-like tail, as well as wings with flight feathers similar to those of modern birds. It is not considered a direct ancestor of birds, though it is possibly closely related to the true ancestor. The earliest known avialan fossils come from the Tiaojishan Formation of China, which has been dated to the late Jurassic period (Oxfordian stage), about 160 million years ago. The avialan species from this time period include "Anchiornis huxleyi", "Xiaotingia zhengi", and "Aurornis xui". The well-known early avialan, "Archaeopteryx", dates from slightly later Jurassic rocks
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.