family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
, is composed of
rodent
Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...
s native to
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...
and includes the domestic guinea pig, wild cavies, and the largest living rodent, the
capybara
The capybara or greater capybara (''Hydrochoerus hydrochaeris'') is the largest living rodent, native to South America. It is a member of the genus '' Hydrochoerus''. The only other extant member is the lesser capybara (''Hydrochoerus isthmi ...
. They are found across South America in open areas from moist
savanna
A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...
desert
A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the la ...
. This family of rodents has fewer members than most other rodent families, with 19 species in seven genera in three subfamilies.
Characteristics
With the exception of the
mara
Mara or MARA may refer to:
Arts and entertainment Fictional characters
* Mara (''Doctor Who''), an evil being in two ''Doctor Who'' serials
* Mara (She-Ra), fictional characters from the ''She-Ra and the Princesses of Power'' and ''The New Advent ...
s, which have a more
rabbit
Rabbits are small mammals in the family Leporidae (which also includes the hares), which is in the order Lagomorpha (which also includes pikas). They are familiar throughout the world as a small herbivore, a prey animal, a domesticated ...
-like appearance, caviids have short, heavy bodies and large heads. Most have no visible
tail
The tail is the elongated section at the rear end of a bilaterian animal's body; in general, the term refers to a distinct, flexible appendage extending backwards from the midline of the torso. In vertebrate animals that evolution, evolved to los ...
s. They range in size from the smaller cavies at 22 cm in body length, and 300 grams in weight, up to the
capybara
The capybara or greater capybara (''Hydrochoerus hydrochaeris'') is the largest living rodent, native to South America. It is a member of the genus '' Hydrochoerus''. The only other extant member is the lesser capybara (''Hydrochoerus isthmi ...
, the largest of all rodents at 106 to 134 cm in length, and body weights of 35 to 66 kilograms. Even larger forms existed in the
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Phugatherium'', which was about the size of a
tapir
Tapirs ( ) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a Suidae, pig, with a short, prehensile nose trunk (proboscis). Tapirs inhabit jungle and forest regions of South America, South and Centr ...
.
They are
herbivore
A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat ...
s, eating tough grasses or softer leaves, depending on species. The
dental formula
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology ...
is similar to that of various other rodents: . Females give birth to two or three furred and active young after a
gestation
Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregn ...
period of 50 to 90 days in most species, or 150 days in the capybara. In most species, they are sexually mature within a few months of birth, although in capybaras, maturity is not reached until around 18 months.
Social organisation varies widely among the group. Many cavies are promiscuous, forming no long-lasting social groups, although, in some species, males maintain harems of two or more females. In contrast, maras are
monogamous
Monogamy ( ) is a relationship of two individuals in which they form a mutual and exclusive intimate partnership. Having only one partner at any one time, whether for life or serial monogamy, contrasts with various forms of non-monogamy (e.g. ...
, and form temporary colonial crèches to care for the young of multiple mothers. Capybaras live in groups of around 10 individuals, and sometimes many more, each with a single dominant male, and a number of females, subordinate males, and juveniles.
Classification
The family Caviidae is a sister group to the family
Dasyproctidae
Dasyproctidae is a family of large South American rodents, comprising the agoutis and acouchis. Their fur is a reddish or dark colour above, with a paler underside. They are herbivore, herbivorous, often feeding on ripe fruit that falls from tree ...
, both of which are members of the superfamily Cavioidea. Fossils caviids first appeared during the middle of the
Miocene
The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...
epoch in South America.
Family Caviidae
*Subfamily
Caviinae
Caviinae is a subfamily uniting all living members of the family Caviidae with the exception of the maras, capybaras, and '' Kerodon''. The subfamily traditionally contained the guinea pig or cavy-like forms along with the cursorially adapted ...
:
guinea pig
The guinea pig or domestic guinea pig (''Cavia porcellus''), also known as the cavy or domestic cavy ( ), is a species of rodent belonging to the genus ''Cavia'', family Caviidae. Animal fancy, Breeders tend to use the name "cavy" for the ani ...
s (cavies)
**Genus ''
Cavia
''Cavia'' is a genus in the subfamily Caviinae that contains the rodents commonly known as the guinea pigs or cavies. The best-known species in this genus is the domestic guinea pig, ''Cavia porcellus'', a meat animal in South America and a com ...
Capybara
The capybara or greater capybara (''Hydrochoerus hydrochaeris'') is the largest living rodent, native to South America. It is a member of the genus '' Hydrochoerus''. The only other extant member is the lesser capybara (''Hydrochoerus isthmi ...