I don't know if I should be the first to mention it, but it was suggested numerous times at SVP that Archaeoraptor is itself a chimaera. Specifically, the head looks (to me) dromaeosaurid or troodontid, the torso like that of a bird, and the feet like a tiny avimimid or mononykine. The tail looks like a rather unnatural long, stiff rod. Do with this what you will. --Nick P.