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Group of animals that walk on the tips of their toes or hooves
elephants and relatives, sometimes called ungulates or subungulates

Ungulates ('/ʌ//ŋ//ɡ//j//ʊ//l//eɪ//t//s//, // //ɡ//j//ə// //, // //l//ɪ//t//s//, // //l//ə//t//s/ UNGgyuulayts, gyə , lits, ləts) are members of the diverse clade Euungulata ("true ungulates"), which primarily consists of large mammals with hooves. Once part of the clade "Ungulata" along with the clade Paenungulata, "Ungulata" has since been determined to be a polyphyletic and thereby invalid clade based on molecular data. As a result, true ungulates had since been reclassified to the newer clade Euungulata in 2001 within the clade Laurasiatheria while Paenungulata has been reclassified to a distant clade Afrotheria. Living ungulates are divided into two orders: Perissodactyla including equines, rhinoceroses, and tapirs; and Artiodactyla including cattle, antelope, pigs, giraffes, camels, sheep, deer, and hippopotamuses, among others. Cetaceans such as whales, dolphins, and porpoises are also classified as artiodactyls, although they do not have hooves. Most terrestrial ungulates use the hoofed tips of their toes to support their body weight while standing or moving. Two other orders of ungulates, Notoungulata and Litopterna, both native to South America, became extinct at the end of the Pleistocene, around 12,000 years ago. The term means, roughly, "being hoofed" or "hoofed animal". As a descriptive term, "ungulate" normally excludes cetaceans as they do not possess most of the typical morphological characteristics of other ungulates, but recent discoveries indicate that they were also descended from early artiodactyls. Ungulates are typically herbivorous and many employ specialized gut bacteria to allow them to digest cellulose, though some members may deviate from this: several species of pigs and the extinct entelodonts are omnivorous, while cetaceans and the extinct mesonychians are carnivorous.

Ungulate is from the Late Latin adjective ungulatus, 'hoofed'. Ungulatus is a diminutive form of Latin unguis, 'nail' (finger nail; toe nail).

Euungulata is a clade (or in some taxonomies, a grand order) of mammals. The two extant orders of ungulates are the Perissodactyla (odd toed ungulates) and Artiodactyla (even toed ungulates). Hyracoidea (hyraxes), Sirenia (sea cows) (dugongs and manatees) and Proboscidea (elephants) were in the past grouped within the clade "Ungulata", later found to be a polyphyletic and now invalid clade. The three orders of Paenungulata are now considered a clade and grouped in the Afrotheria clade, while Euungulata is now grouped under the Laurasiatheria clade. and molecular work found that aardvarks, hyraxes, sea cows, and elephants were more closely related to each other and to sengis, tenrecs, and golden moles than to the perissodactyls and artiodactyls, and form the clade Afrotheria. Elephants, sea cows, and hyraxes were grouped together in the clade Paenungulata, while the aardvark has been considered as either a close relative to them or a close relative to sengis in the clade Afroinsectiphilia. This is a striking example of convergent evolution. There is now some dispute as to whether this smaller Euungulata is a cladistic (evolution based) group, or merely a phenetic group (form taxon) or folk taxon (similar, but not necessarily related). Some studies have indeed found the mesaxonian ungulates and paraxonian ungulates to form a monophyletic lineage, closely related to either the Ferae (the carnivorans and the pangolins) in the clade Fereuungulata or to the bats. Other studies found the two orders not that closely related, as some place the perissodactyls as close relatives to bats and Ferae in Pegasoferae and others place the artiodactyls as close relatives to bats.

thumb|left|upright=1.3|The anatomy of a dolphin, showing its skeleton, major organs, tail, and body shape
Ungulates were in high diversity in response to sexual selection and ecological events; most ungulates lack a collar bone. Terrestrial ungulates were for the most part herbivores, with some of them being grazers. However, there were exceptions to this as pigs, peccaries, hippos and duikers were known to have an omnivorous diet. Some cetaceans were the only modern ungulates that were carnivores; baleen whales consume significantly smaller animals in relation to their body size, such as small species of fish and krill; toothed whales, depending on the species, can consume a wide range of species: squid, fish, sharks, and other species of mammals such as seals and other whales. In terms of ecosystem ungulates have colonized all corners of the planet, from mountains to the ocean depths; grasslands to deserts and some have been domesticated by humans.

Ungulates have developed specialized adaptations, especially in the areas of cranial appendages, dentition, and leg morphology including the modification of the astragalus (one of the ankle bones at the end of the lower leg) with a short, robust head.

Most ungulates have developed reduced canine teeth and specialized molars, including bunodont (low, rounded cusps) and hypsodont (high crowned) teeth. The development of hypsodonty has been of particular interest as this adaptation was strongly associated with the spread of grasslands during the Miocene about 25 million years ago. As forest biomes declined, grasslands spread, opening new niches for mammals. Many ungulates switched from browsing diets to grazing diets, and possibly driven by abrasive silica in grass, hypsodonty became common. However, recent evidence ties the evolution of hypsodonty to open, gritty habitats and not the grass itself. This is termed the Grit, not grass hypothesis. Some ungulates completely lack upper incisors and instead have a dental pad to assist in browsing. It can be found in camels, ruminants, and some toothed whales; modern baleen whales were remarkable in that they have baleen instead to filter out the krill from the water. On the other spectrum teeth have been evolved as weapons or sexual display seen in pigs and peccaries, some species of deer, musk deer, hippopotamuses, beaked whales and the Narwhal, with its long canine tooth.

thumb|upright|Velvet covers a growing antler and provides it with blood, supplying oxygen and nutrients. Ungulates have evolved a variety of cranial appendages that can be found in cervoids (with the exception of musk deer). In oxen and antelope, the size and shape of the horns varies greatly but the basic structure is always a pair of simple bony protrusions without branches, often having a spiral, twisted, or fluted form, each covered in a permanent sheath of keratin. The unique horn structure is the only unambiguous morphological feature of bovids that distinguishes them from other pecorans. Male horn development has been linked to sexual selection, while the presence of horns in females is likely due to natural selection. The horns of females are usually smaller than those of males and are sometimes of a different shape. The horns of female bovids are thought to have evolved for defense against predators or to express territoriality, as nonterritorial females, which are able to use crypsis for predator defense, often lack horns. Each antler grows from an attachment point on the skull called a pedicle. While an antler is growing it is covered with highly vascular skin called velvet, which supplies oxygen and nutrients to the growing bone. Antlers are considered one of the most exaggerated cases of male secondary sexual traits in the animal kingdom, and grow faster than any other mammal bone. Growth occurs at the tip, initially as cartilage that is then mineralized to become bone. Once the antler has achieved its full size, the velvet is lost and the antler's bone dies. This dead bone structure is the mature antler. In most cases, the bone at the base is destroyed by osteoclasts and the antlers eventually fall off. Ossicones are horn like (or antler like) protuberances found on the heads of giraffes and male okapis. They are similar to the horns of antelopes and cattle save that they are derived from ossified cartilage, and that the ossicones remain covered in skin and fur rather than horn. Pronghorn cranial appendages are unique. Each "horn" of the pronghorn is composed of a slender, laterally flattened blade of bone that grows from the frontal bones of the skull, forming a permanent core. As in the Giraffidae, skin covers the bony cores, but in the pronghorn it develops into a keratinous sheath that is shed and regrown on an annual basis. Unlike the horns of the family Bovidae, the horn sheaths of the pronghorn are branched, each sheath possessing a forward pointing tine (hence the name pronghorn). The horns of males are well developed.