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So, in essence, the ungulates still exist as a biological group, but just not as a taxonomic one (much like the insectivores, which are a valid feeding guild, but the Insectivora is no longer a valid taxon).
As it currently stands, the Laurasiatheria superorder holds eight orders and the ungulates are split -- unevenly -- between two of them: the Artiodactyla and Perissodactyla.
It seems that while most morphological taxonomists generally support the idea of a clade uniting the two orders, some disagree that the Cetacea evolved from within the Artiodactyla; instead, they prefer to consider the Cetacea and Artiodactyla sister groups (i.e.
Taxonomy: There is an expression that goes something along the lines of ‘nothing that is worth doing is ever easy’.
While I can think of a few things to which that idea doesn’t apply, it certainly seems applicable to the task of classifying mammals.
The order holds ten families, between 79 and 81 genera (depending on the classification one prefers) and around 230 species, including pigs, peccaries, hippopotamuses, camels, giraffes, sheep, cows and, of course, deer.
The Artiodactyla can be further divided into four suborders; the one we’re interested in is the Ruminatia.
Perissodactylian taxonomy is fascinating in its own right -- especially a molecular study published in 2006, which suggested that the perissodactylians should be grouped with the bats, carnivores and pangolins in the superorder Pegasoferae -- but it is not directly relevant to us here and I won’t pursue it further.