Ferungulata is traditionally a clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 with the rank of cohort within the placental mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

s. Established by George Gaylord Simpson
George Gaylord Simpson
George Gaylord Simpson was an American paleontologist. Simpson was perhaps the most influential paleontologist of the twentieth century, and a major participant in the modern evolutionary synthesis, contributing Tempo and mode in evolution , The meaning of evolution and The major features of...

 in 1945, it includes the Carnivora
The diverse order Carnivora |Latin]] carō "flesh", + vorāre "to devour") includes over 260 species of placental mammals. Its members are formally referred to as carnivorans, while the word "carnivore" can refer to any meat-eating animal...

, Perissodactyla and Artiodactyla as well as Tubulidentata and a superorder, Paenungulata
Paenungulata is a taxon that groups some remarkable mammals, including three orders that are extant: Proboscidea , Sirenia , and Hyracoidea . At least two more orders are known only as fossils, namely Embrithopoda and Desmostylia...

, plus a number of orders known only as fossils. Although Simpson placed whales (Cetacea
The order Cetacea includes the marine mammals commonly known as whales, dolphins, and porpoises. Cetus is Latin and is used in biological names to mean "whale"; its original meaning, "large sea animal", was more general. It comes from Ancient Greek , meaning "whale" or "any huge fish or sea...

) in a separate cohort, recent evidence linking them to Artiodactyla would mean that they belong here as well.

Simpson established the grouping on the basis of morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....

 criteria, but this traditional understanding of Ferungulata has been challenged by a more recent classification, relying upon genetic
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....

 criteria, in which his ferungulate orders are divided between two distinct cohorts, Afrotheria
Afrotheria is a clade of mammals, the living members of which belong to groups from Africa or of African origin: golden moles, sengis , tenrecs, aardvarks, hyraxes, elephants and sea cows. The common ancestry of these animals was not recognized until the late 1990s...

 and Laurasiatheria
Laurasiatheria is a large group of placental mammals believed to have originated on the northern supercontinent of Laurasia. It includes shrews, hedgehogs, pangolins, bats, whales, most hoofed mammals, and carnivorans, among others....

. Advocates of this newer system redefine Ferungulata as a clade within Laurasiatheria, comprising the larger portion of the former Ferungulata and including 'true' ungulate
Ungulates are several groups of mammals, most of which use the tips of their toes, usually hoofed, to sustain their whole body weight while moving. They make up several orders of mammals, of which six to eight survive...

s (Perissodactyla and Artiodactyla), whales and Carnivora, with the addition of pangolins (Pholidota), but excluding Tubulidentata and paenungulates; a newer clade name, Scrotifera
Scrotifera is a proposed clade of mammals within Laurasiatheria, consisting of the following orders and their common ancestors:* Chiroptera* Carnivora* Pholidota* Perissodactyla* Cetacea* ArtiodactylaIt is based on evidence from molecular phylogenetics....

, has thus been proposed.
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