In most classifications of the past century, the rails (Rallidae) have been placed in the Gruiformes with the cranes and their allies, including the Sunbittern, bustards, Limpkin, sungrebes, trumpeters, seriemas, and the Kagu. In a few classifications the rails have been assigned to an Order Ralliformes; in other classifications some taxa now usually placed in the Charadriiformes have been assigned to the Gruiformes, as relatives of the Rallidae. DNA-DNA hybridization data support other evidence that the rails are closer to the typical gruiforms than to any other group, but that they have no close relatives within the Gruiformes.