Dragon bones are extremely rare in the fossil record due to their fragility. This specimen was recently discovered in China in lake bed sediments.
Dragons presumably evolved from a species of "bat winged" dinosaurs from the group Scansoriopterygidae, such as Yi Qi or Ambopteryx longibrachium.
As part of their evolution for flight the bones of dragons became exceedingly fine and dendritic to minimise weight.
Competition with the feathered dinosaurs probably lead to the extinction of dragons about 140 million years ago, though it is possible that more recent fossils may be found in the future.
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