HOME

TheInfoList



OR:

The rock cavy or ''mocó'' (''Kerodon rupestris'') is a
cavy Caviidae, the cavy family, is composed of rodents native to South America and includes the domestic guinea pig, wild cavies, and the largest living rodent, the capybara. They are found across South America in open areas from moist savanna to t ...
species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
to eastern
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
which has also been introduced to the
Atlantic The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for se ...
island of
Fernando de Noronha Fernando de Noronha (), officially the State District of Fernando de Noronha () and formerly known as the Federal Territory of Fernando de Noronha () until 1988, is an archipelago in the Atlantic Ocean, part of the state of Pernambuco, Brazil, and ...
. The rock cavy is called ''mocó'' in
Brazilian Portuguese Brazilian Portuguese (; ; also known as pt-BR) is the set of Variety (linguistics), varieties of Portuguese language native to Brazil. It is spoken by almost all of the 203 million inhabitants of Brazil and widely across the Brazilian diaspora ...
, and ''koriko pexerumen'' in the
Xukuru language Xukuru (Xucuru, Shukurú, Ichikile, ) is a poorly attested extinct language of Brazil. It was also known as ''Kirirí, Kirirí-Xokó'', and ''Ichikile''. It is known only from a few word lists and a sketch by Geraldo Lapenda (1962).Lapenda, Gera ...
of
Pernambuco Pernambuco ( , , ) is a States of Brazil, state of Brazil located in the Northeast Region, Brazil, Northeast region of the country. With an estimated population of 9.5 million people as of 2024, it is the List of Brazilian states by population, ...
, Brazil.


Description

The rock cavy is a fairly large
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 ...
weighing up to . Like other
cavy Caviidae, the cavy family, is composed of rodents native to South America and includes the domestic guinea pig, wild cavies, and the largest living rodent, the capybara. They are found across South America in open areas from moist savanna to t ...
species, their tails are
vestigial Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on co ...
or absent. Their backs are grey-brown and their
bellies ''Bellies'' is the 2023 debut novel of British-Malaysian writer Nicola Dinan. Premise Set in London, ''Bellies'' follows the story of Ming and Tom, two lovers who meet at a drag party, both dressed as women. Ming begins to transition and accep ...
tan to light brown. In appearance and habit, they closely resemble the unrelated African
rock hyrax The rock hyrax (; ''Procavia capensis''), also called dassie, Cape hyrax, rock rabbit, and (from some interpretations of a word used in the King James Bible) coney, is a medium-sized terrestrial mammal native to Africa and the Middle East. Common ...
es (an example of
convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last comm ...
). They are herbivorous, feeding on seeds and leaves of the scrubby vegetation that grows in their territories. This vegetation consists of tender leaves and certain species of creeper.


Distribution and habitat

Rock cavies are found in dry, rocky areas with low, scrubby
vegetation Vegetation is an assemblage of plants and the ground cover they provide. It is a general term, without specific reference to particular Taxon, taxa, life forms, structure, Spatial ecology, spatial extent, or any other specific Botany, botanic ...
, and they prefer to reside close to stony mountainsides and
hill A hill is a landform that extends above the surrounding terrain. It often has a distinct summit, and is usually applied to peaks which are above elevation compared to the relative landmass, though not as prominent as Mountain, mountains. Hills ...
s. They are native to eastern
Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...
, from eastern
Piauí Piauí ( ) is one of the states of Brazil, located in the country's Northeast Region, Brazil, Northeast Region. The state has 1.6% of the Brazilian population and produces 0.7% of the Brazilian GDP. Piauí has the shortest coastline of any coas ...
state to
Minas Gerais Minas Gerais () is one of the 27 federative units of Brazil, being the fourth largest state by area and the second largest in number of inhabitants with a population of 20,539,989 according to the 2022 Brazilian census, 2022 census. Located in ...
state, and have been introduced to the island of
Fernando de Noronha Fernando de Noronha (), officially the State District of Fernando de Noronha () and formerly known as the Federal Territory of Fernando de Noronha () until 1988, is an archipelago in the Atlantic Ocean, part of the state of Pernambuco, Brazil, and ...
, off the eastern coast of Brazil.


Phylogeny

Rock cavies belong to the order
Rodentia Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...
, suborder
Hystricomorpha Hystricomorpha (from Greek ὕστριξ, ''hystrix'' 'porcupine' and Greek μορφή, ''morphē'' 'form') is a term referring to families and orders of rodents which has had many definitions throughout its history. In the broadest sense, it ref ...
, based on their porcupine-like jaw muscles. They are in the family
Caviidae Caviidae, the cavy family (biology), family, is composed of rodents native to South America and includes the domestic guinea pig, wild cavies, and the largest living rodent, the capybara. They are found across South America in open areas from mo ...
(
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 ...
-like rodents), which has three subfamilies (formerly two); rock cavies have recently been placed in a new subfamily
Hydrochoerinae Hydrochoerinae is a subfamily of Caviidae, consisting of two living genera, ''Hydrochoerus'', the capybaras, and '' Kerodon'', the rock cavies. In addition, a number of extinct genera related to capybaras should also be placed in this subfamily. ...
, with 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 ...
s, and with the closely related rainforest-dwelling acrobatic cavy.


Behavior

Rock cavies usually shelter in crevices. They may be seen resting at all times of day, but are
crepuscular In zoology, a crepuscular animal is one that is active primarily during the twilight period, being matutinal (active during dawn), vespertine (biology), vespertine/vespertinal (active during dusk), or both. This is distinguished from diurnalit ...
– active mostly at dawn and dusk. They are able to climb, which makes reaching leaves, seeds, and occasional fruits easier. Rock cavies live in groups, centered around rock-sheltered dens. Each rock cavy group has an
alpha Alpha (uppercase , lowercase ) is the first letter of the Greek alphabet. In the system of Greek numerals, it has a value of one. Alpha is derived from the Phoenician letter ''aleph'' , whose name comes from the West Semitic word for ' ...
or dominant male and several females. The males are
territorial A territory is an area of land, sea, or space, belonging or connected to a particular country, person, or animal. In international politics, a territory is usually a geographic area which has not been granted the powers of self-government, ...
, defending rock pile shelters against other adult males. The rock piles are chosen to impress the females; once a female chooses a rock pile, she indirectly chooses its guardian as her mate. They can sometimes display
homosexual Homosexuality is romantic attraction, sexual attraction, or sexual behavior between people of the same sex or gender. As a sexual orientation, homosexuality is "an enduring pattern of emotional, romantic, and/or sexual attractions" exc ...
behavior, with males courting other males. Some paedophilic behavior has also been displayed, with adult males courting juvenile males. Studies show that rock cavies have a direct link between their retina and the mediodorsal nucleus in the thalamus, which may provide them with strong visual recognition, emotional learning, and/or enhanced object-reward associative memory. This may partly explain why they are found living in large groups.


Reproduction

Females weigh 700-800 g and give birth to only one or two young, but several litters per year are common. The gestation period averages 75 days. The newborn cavies weigh 90 g. The placenta for a rock cavy is similar to other hystricomorph rodents: They have several lobes that are lined with blood vessels and undergo a counter-current blood flow. Blood vessels run from the mother along the placenta and then vessels run from the fetus back over the mother's vessels. This allows for a better flow of oxygen between the mother and the fetus.


Parental care

The young are able to eat solid food at 3 days old, but continue to nurse for up to 7 weeks. The milk produced for these young is very dense in energy. This may be due to the lack of water availability in their environment. Both male and female rock cavies care for their young. When both parents are present, the females spend more time with their young than the males do. When the male is absent, the females spend more time with their young than they do when the male is present. Females that raise young on their own are more aggressive than females that raise the young with a partner. The young raised by single mothers also gain more weight while nursing compared to those raised by both parents.


Threats and protection

Rock cavies are
endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
to several protected areas, and reproduce quickly, so they are currently listed as "least concern" on the IUCN Red List. They are frequently hunted as food by humans, which resulted in population decline of 30% in the last 10 years. Their range is also being reduced due to deforestation. Efforts are underway to breed rock cavies in captivity as a potential food source.


Footnotes


References


Further reading

*


External links

{{Taxonbar, from=Q1769116 Cavies Rodents of Brazil Endemic mammals of Brazil Mammals described in 1820 Taxa named by Prince Maximilian of Wied-Neuwied