''Dusicyon avus'' is an
extinct
Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...
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), ...
of
canid
Canidae (; from Latin, ''canis'', "dog") is a family (biology), biological family of caniform carnivorans, constituting a clade. A member of this family is also called a canid (). The family includes three subfamily, subfamilies: the Caninae, a ...
native to South America during the
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...
and
Holocene
The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...
epochs. It was medium to large, about the size of a
German shepherd
The German Shepherd, also known in Britain as an Alsatian, is a German Dog breed, breed of working dog of medium to large size. The breed was developed by Max von Stephanitz using various Old German herding dogs, traditional German herding dog ...
. It was closely related to the
Falkland Islands wolf ''(Dusicyon australis)'', which descended from a population of ''D. avus''.
It appears to have survived until very recently, perhaps 400 years ago.
Range
''Dusicyon avus'' range extended through the
Pampas
The Pampas (; from Quechua 'plain'), also known as the Pampas Plain, are fertile South American low grasslands that cover more than and include the Argentine provinces of Buenos Aires, La Pampa, Santa Fe, Entre Ríos, and Córdoba; all o ...
and
Patagonia
Patagonia () is a geographical region that includes parts of Argentina and Chile at the southern end of South America. The region includes the southern section of the Andes mountain chain with lakes, fjords, temperate rainforests, and glaciers ...
in the south-central and southern parts of South America, with an estimated range of around 762 351 km². Its fossils have been found in the
Luján Formation of
Argentina
Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...
, the
Chui Formation of
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 ...
, the
Milodón Cave in
Chile
Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...
and the
Sopas Formation of
Uruguay
Uruguay, officially the Oriental Republic of Uruguay, is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast, while bordering the Río de la Plata to the south and the A ...
.
Diet and ecology
Its diet seems to have been more carnivorous than extant foxes based on δ
13C and δ
15N values, probably mostly preying on small mammals but also scavenging on large carcasses. This is in contrast to the warrah, whose diet was restricted to the seabirds and seal pups available on the
Falkland Islands
The Falkland Islands (; ), commonly referred to as The Falklands, is an archipelago in the South Atlantic Ocean on the Patagonian Shelf. The principal islands are about east of South America's southern Patagonian coast and from Cape Dub ...
. Morphologically, ''D. avus'' and ''D. australis'' are most similar to
jackal
Jackals are Canidae, canids native to Africa and Eurasia. While the word has historically been used for many canines of the subtribe Canina (subtribe), canina, in modern use it most commonly refers to three species: the closely related black-b ...
s, suggesting a similar ecological niche.
Relationship to humans
A grave of the late second millennium BCE at Loma de los Muertos in
General Conesa, Río Negro Argentina contains a sub-adult ''D. avus'', buried in a human mortuary context in a comparable manner to adjacent human burials. It may have been kept as a pet and been considered part of the human social group. Another example is found in Cañada Seca,
Mendoza Argentina.
Extinction
Dating of extinction
''Dusicyon avus'', according to earlier estimates,
became extinct around 1000
BCE, with possibilities that it became extinct as recently as 500 – 300 years
BP.
Recent research confirms more recent dates, with the last appearance datum in the Pampean Region being 700
BP (1232–1397 AD) and southernmost Patagonia at 400 years BP (1454–1626 AD).
Charles Darwin
Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English Natural history#Before 1900, naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all speci ...
in
The Voyage of the Beagle stated that "many sealers,
Gaucho
A gaucho () or gaúcho () is a skilled horseman, reputed to be brave and unruly. The figure of the gaucho is a folk symbol of Argentina, Paraguay, Uruguay, Rio Grande do Sul in Brazil, the southern part of Bolivia, and the south of Chilean Patago ...
s, and
Indians, who have visited these islands
Falklands">Falkland_Islands.html" ;"title="he
Falklands all maintain that no such animal [the Falkland Islands wolf">warrah">Falkland Islands">Falklands all maintain that no such animal [the Falkland Islands wolf">warrahis found in any part of South America" suggesting that it was unlikely to have been alive at this time. It is possible, but as yet unproven, that some populations of ''D. avus'' may have persisted until the time of European contact. Forty years before the introduction of the South American gray fox to Tierra del Fuego, there are some ethnographic references to the existence of two species of foxes there. Around 1900, the indigenous Selkʼnam people were recorded as recognizing two varieties of foxes, one of which grew to unusual size. If the "big fox" was ''D. avus'', this would indicate that it survived until the 20th century, at least in this location. In 1871
George Musters wrote a description of encountering a fox in Patagonia similar to a warrah, which may have been an account of this species.
Reasons for extinction
The extinction of ''D. avus'' as opposed to the
naive ''D. australis'' is mysterious, as there is no clear reason why a generalised medium sized canid would go extinct, especially at such a late date after the
Quaternary extinction event. There is no compelling evidence that climatic change was the cause of the extinction, nor any evidence that hybridisation with domestic dogs was the cause, as the skull morphology and DNA is consistent from the Late Pleistocene through the Holocene.
''Dusicyon'' was used for ritual purposes by aboriginal peoples in the Late Holocene, and appears to have a high symbolic value and its remains, usually teeth, are found in many archaeological sites.
''D. avus'', despite its wide range, has a low
genetic diversity
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species. It ranges widely, from the number of species to differences within species, and can be correlated to the span of survival for a species. It is d ...
in tested samples, suggesting a possible low population or
genetic bottleneck before extinction.
It is likely that a combination of both climatic and anthropogenic factors was the cause of their demise.
See also
*
Fuegian dog
References
{{Taxonbar, from=Q5815268
Dusicyon
Extinct mammals of South America
Pleistocene mammals of South America
Lujanian
Sopas Formation
Pleistocene Argentina
Fossils of Argentina
Pleistocene Brazil
Fossils of Brazil
Pleistocene Chile
Fossils of Chile
Pleistocene Uruguay
Fossils of Uruguay
Fossil taxa described in 1866
Mammals described in 1866
Taxa named by Hermann Burmeister