Suina
Encyclopedia
The suborder Suina are lineage of mammals that today includes the families Suidae
and Tayassuidae and their fossil kin.
(pig family) and Tayassuidae (peccary family). Some morphological
studies also identified the hippopotamus family Hippopotamidae
among the Suina.
The oreodont
s, a branch of the tylopoda
, were often considered suines due to the popular, though inaccurate, description of them as "ruminating hogs". Oreodonts are not suines, but are more closely related to camels. Similarly the precursors of the oreodonts, the entelodont
s have long been classified as members of the Suina. Spaulding et al. have found them to be closer to whale
s, than to pig
s in his Cetacodontamorpha
.
Hippopotamus were once thought to be part of the Suina, but a growing body of morphological and genetic evidence has suggested that they share a common ancestor not with Suina, but with Cetaceans—the Order which includes whales and dolphins. Whales and artiodactyls form a clade
called Cetartiodactyla
.
The most recent research into the origins of hippopotamidae suggests that hippos and whales shared a common semi-aquatic ancestor that branched off from other Artiodactyls around . Descendants of this hypothesized ancestor likely split into two branches around . One branch would evolve into cetaceans
, possibly beginning with the proto-whale Pakicetus
from and other early whale ancestors, known as Archaeoceti
, which eventually underwent aquatic adaptation
into the almost completely aquatic cetacea
ns.
s and deer
, have front teeth only on the bottom. This doesn't let them chew very well, thus they swallow and regurgitate their food to allow rumination
.
Most even-toed ungulates have a four-chambered stomach. In contrast, the Suina have a simple stomach that allows an omnivorous diet.
Most members of Suina have toes rather than hooves. While most artiodactyls have long slender legs, the Suina generally have short, stubby legs.
Suidae
Suidae is the biological family to which pigs belong. In addition to numerous fossil species, up to sixteen extant species are currently recognized, classified into between four and eight genera...
and Tayassuidae and their fossil kin.
Classification
The suborder Suina includes SuidaeSuidae
Suidae is the biological family to which pigs belong. In addition to numerous fossil species, up to sixteen extant species are currently recognized, classified into between four and eight genera...
(pig family) and Tayassuidae (peccary family). Some 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....
studies also identified the hippopotamus family Hippopotamidae
Hippopotamidae
Hippopotamuses are the members of the family Hippopotamidae. They are the only extant artiodactyls which walk on four toes on each foot.- Characteristics :...
among the Suina.
The oreodont
Oreodont
Oreodons, sometimes called prehistoric "ruminating hogs," were a family of cud-chewing plant-eater with a short face and tusk-like canine teeth...
s, a branch of the tylopoda
Tylopoda
Tylopoda is a suborder of terrestrial herbivorous even-toed ungulates belonging to Artiodactyla. They are extant in the wild in their native ranges of South America and Asia, while Australian feral camels are an introduced species. The group has a long fossil history in North America and Europe...
, were often considered suines due to the popular, though inaccurate, description of them as "ruminating hogs". Oreodonts are not suines, but are more closely related to camels. Similarly the precursors of the oreodonts, the entelodont
Entelodont
Entelodonts, sometimes nicknamed hell pigs or terminator pigs, is an extinct family of pig-like omnivores endemic to forests and plains of North America, Europe, and Asia from the middle Eocene to early Miocene epochs , existing for approximately .-Taxonomy:Entelodontidae was named by Richard...
s have long been classified as members of the Suina. Spaulding et al. have found them to be closer to whale
Whale
Whale is the common name for various marine mammals of the order Cetacea. The term whale sometimes refers to all cetaceans, but more often it excludes dolphins and porpoises, which belong to suborder Odontoceti . This suborder also includes the sperm whale, killer whale, pilot whale, and beluga...
s, than to pig
Pig
A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives...
s in his Cetacodontamorpha
Cetacodontamorpha
Cetancodontamorpha is a total clade of artiodactyls defined, according to Spaulding et al., as "Cetancodonta plus all extinct taxa more closely related to extant members of Cetancodonta than to any other living species." Cetancodonta is the crown clade containing Cetacea and hippopotamuses...
.
Hippopotamus were once thought to be part of the Suina, but a growing body of morphological and genetic evidence has suggested that they share a common ancestor not with Suina, but with Cetaceans—the Order which includes whales and dolphins. Whales and artiodactyls form a clade
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...
called Cetartiodactyla
Cetartiodactyla
Cetartiodactyla is the clade in which whales and even-toed ungulates have currently been placed. The term was coined by merging the name for the two orders, Cetacea and Artiodactyla, into a single word. The term Cetartiodactyla reflects the idea that whales evolved within the artiodactyls...
.
The most recent research into the origins of hippopotamidae suggests that hippos and whales shared a common semi-aquatic ancestor that branched off from other Artiodactyls around . Descendants of this hypothesized ancestor likely split into two branches around . One branch would evolve into cetaceans
Evolution of cetaceans
The cetaceans are marine mammal descendants of land mammals. Their terrestrial origins are indicated by:* Their need to breathe air from the surface;* The bones of their fins, which resemble the limbs of land mammals...
, possibly beginning with the proto-whale Pakicetus
Pakicetus
Pakicetus is a genus of extinct terrestrial carnivorous mammal of the family Pakicetidae which was endemic to Pakistan from the Eocene .Pakicetus existed for approximately...
from and other early whale ancestors, known as Archaeoceti
Archaeoceti
Archaeocetes, or "ancient whales", are a paraphyletic group of cetaceans that gave rise to the modern cetaceans.The archaeocetes were once thought to have evolved from the mesonychids, based on dental characteristics...
, which eventually underwent aquatic adaptation
Aquatic adaptation
Several animal groups have undergone aquatic adaptation, going from being purely terrestrial animals to living at least part of the time in water. The adaptations in early speciation tend to develop as the animal ventures into water in order to find available food. As successive generations spend...
into the almost completely aquatic cetacea
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...
ns.
Anatomy
The anatomy of the Suina is different compared to other even-toed ungulates. For example, they have maxillary (upper) teeth in front, which allow for proper chewing of food. In contrast, other even-toed ungulates, such as goatGoat
The domestic goat is a subspecies of goat domesticated from the wild goat of southwest Asia and Eastern Europe. The goat is a member of the Bovidae family and is closely related to the sheep as both are in the goat-antelope subfamily Caprinae. There are over three hundred distinct breeds of...
s and deer
Deer
Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...
, have front teeth only on the bottom. This doesn't let them chew very well, thus they swallow and regurgitate their food to allow rumination
Cud
Cud is a portion of food that returns from a ruminant's stomach in the mouth to be chewed for the second time. More accurately, it is a bolus of semi-degraded food regurgitated from the reticulorumen of a ruminant. Cud is produced during the physical digestive process of rumination, or "chewing the...
.
Most even-toed ungulates have a four-chambered stomach. In contrast, the Suina have a simple stomach that allows an omnivorous diet.
External links
- http://www.paleocene-mammals.de/condylarths.htm
- http://www.ultimateungulate.com/Cetartiodactyla.html