The formation and positioning of cilia in Ciona intestinalis embryos in relation to the generation and evolution of chordate left-right asymmetry

► Ciona embryos develop monocilia immediately prior to asymmetric gene expression. ► Cilia are polarised relative to the AP axis at the posterior of each cell. ► Ultrastructure indicates cilia lack motility. ► The equivalent of nodal flow is not present in this species.