Xu et al. reply

Replying to Richard O. Prum , 10.1038/nature09480 Prum1 identifies the unusual feathers in the smaller Similicaudipteryx specimen as immature, and suggests that the different morphologies preserved in the smaller and larger specimens represent different growth stages of a single feather type rather than successive feather generations of different types. Although this new proposal is very interesting, we do not agree that it is better supported...