A 2008 documentary about a Chinese palaeontologist who discovered the fossil of a four-winged dinosaur in 2o02 and subsequently claimed that the species is the link between dinosaurs and birds, but the claim was controversial and many other experts in his field disagreed with the link. Opposing sides appear in this documentary and use skeletal reproductions to demonstrate their argument and attempt to convince that their version of evolution is the correct one. The experts on neither side of the debate could explain how the four-winged creature was able to fly, leading to the creation of a detailed scale model for wind tunnel testing.
Xu Xing who discovered the 2002 fossil has named more dinosaurs than any other living palaeontologist, and interestingly had originally wanted to become a software designer but was forced by the communist government of China to study Geology. Numerous other four-winged dinosaurs have since been discovered in China, including a giant one in 2014 which had 30 centimetre long feathers, and scientists are now largely in agreement that four-winged dinosaurs were an evolutionary side-branch rather than a direct stepping stone to two wing flight.