According to recent studies (reflected in the diagram below), the closest relatives of Ferae are Perissodactyla (horses, tapirs and rhinos) and Cetartiodactyla (which combines Artiodactyla--camels, pigs, ruminants and hippos—with Cetacea--whales and dolphins).
Within Fereuungulata, Carnivora and Pholidota form the clade Ferae while Cetacea and Artiodactyla form Cetartiodactyla.
There is uncertainty regarding the placement of Perissodactyla; a grouping with Ferae has been proposed as the clade Zooamata while a grouping with Cetartiodactyla has been proposed as the clade Euungulata ("true ungulates").
A conflicting proposal links the Perissodactyla and Cetartiodactyla in a clade named Euungulata.