Therizinosaurs and EBFF's

©Pavel Riha

Going backwards in the history of feather discoveries we hit the previously largest known feathered dinosaur. Elongate Broad Filamentous Feathers, the type of feathers discovered along the fossilized remains of Beipiaosaurus inexpectus, were long simple feathers rising beyond the down feathers. These longer feathers were most likely used for signalling and display while the down feathers were used to insulate the body; though Xing Xu stated that the team did not want to make any idle speculations. Therizinosaurs like Beipiaosaurus were theropods that, unlike many of their cousins, were herbivores. We have discussed these herbivores before, so there should not be too much background information to go over on therizinosaurs to begin with. What we can focus on, instead, is the Chinese dinosaur in question that was once the largest feathered dinosaur, before the discovery of Yutyrannus.