South American dogs
Though C. familiaris, which co-evolved along with humans in
Eurasia, is found early in the archeological record of North America,
probably as a result of Bering Strait crossings, they arrive much later
in South America. Dogs are reported from 4,5 kya in Ecuador and the
coast of Peru (Stahl 1984; Salomon and Stahl 2008; Stahl 2012), and up
to 10 kya in other parts of the Americas (Allison et al. 1982; van Asch
et al. 2013, Perri et al. 2018).
It seems most probable that any dog present in Chile arrived along
migratory or trade routes from the Andes, with the earliest evidence of
dogs in the form of artistic representations from cultures such as the
Moche (1900 ya – 1300 ya) or the Chimú (1100 kya – 500 ya) (Vásquez
Sánchez et al. 2009). Prates et al. (2010) hypothesize that the presence
of dogs in South America was mainly related to complex societies, such
as the Andean societies of Peru and Ecuador previously mentioned, and
that their arrival in the Southern Cone is related to an increase in
long-distance communication and trade by egalitarian hunter-gatherer
societies of the Pampas and Patagonia. The authors come to these
conclusions based on archaeological deposits in northern Argentina
dating from around 1000 ya (around 500 years before the arrival of the
Spanish), which accords with other archaeological evidence of early dog
presence in southern Brazil (1600 ya, Guedes Milheira et al. 2017) and
in Uruguay (undated remains, but found in multiple-use structures
starting around 1000 ya, López Mazz et al. 2018).
Many morphotypes of dogs may have been present in South America at
different times. Gilmore (1950) lists nine possible breeds of South
American dogs, remarking that parallel selection pressures or
morphological constraints resulted in a terrier-like dog (the Fuegian
dog), a setter-like dog (the Ona dog), a foxhound/greyhound type dog
(the Tehuelche dog), and another terrier-like dog (the Techichi dog), as
well as hairless dogs. The Pre-Columbian origins of these possible
breeds is unknown. Van Asch et al. (2013) confirmed the pre-Columbian
origins of several formally recognised American breeds, including the
Peruvian perro sin pelo (“hairless dog”). Vásquez Sánchez et
al. (2009) summarize many possible morphotypes of South American dogs,
including a short-nosed dog from the Chicama valley, the medium-sized
“helping dog”, the “pet” dog with a long body and short limbs, the
miniature dog similar to a chihuahua, the hairless dog, a short-haired
dog, a Peruvian bulldog, a Peruvian sausage dog, a long-haired Incan
dog, and the Chiribaya shepherd used to herd llamas. Vásquez Sánchez et
al. (2009) also discuss dogs depicted on Moche pots, including a
morphotype consisting of a small or medium-sized spotted dog with a
bulbous head, which appears in a deer-hunting scene among other
contexts. They speculate that this kind of dog might have been used to
corner deer during hunting. Like the Peruvian pitbull (Cossios E. 2018),
many morphotypes may have been bred locally for certain periods of time,
but later allowed to outcross with other morphotypes.
It is unclear whether prehispanic dogs of South America would have
formed significant feral populations, although large packs of feral dogs
are reported by the 18th century (Prevosti et al.
2015), and it is hypothesized that feral populations existed soon after
the beginning of dog domestication in Eurasia (Boitiani & Ciucci 1995).
Dogs, when feral or free ranging, are omnivorous opportunists (Campos et
al. 2007). Dogs that are fed by humans tend to predate much less on wild
prey (Vanak & Gompper 2009). This indicates that, if there were either feral or free-ranging dogs in South America before the arrival of the Europeans, the pressure against succeptible wildlife may have a reasonable historical depth, although maybe not enough to allow prey to evolve adequate anti-predator behaviours.