 However, others have suggested that heterodontosaurids instead share a common ancestor with Marginocephalia (ceratopsians and pachycephalosaurs), a hypothesis that has found support in some early 21st century studies.The clade containing heterodontosaurids and marginocephalians has been named Heterodontosauriformes.Heterodontosaurids have also been seen as basal to both ornithopods and marginocephalians.