TThe oldest dated dog remains in America are 10 150 ± 260 cal BP years old. More or less 10,500 years BP. (Source).
Dogs, forged a symbiotic relationship with humans during our hunter-gatherer days. They shared our prey's meat and fat. However, once we discovered agriculture, and included more complex starches and carbohydrates in our diet, dogs adapted to our new diet.
Natural selection favored dogs who could digest starch, and those who had genes coding for enzymes that degrade carbohydrates fared better than those who didn't.
Nodern dogs have up to 30 copies of an enzyme known as α-2B-amylase or AMY2B, but wolves only have 2. (Source)
This fact could explain the turnover in dog breeds mentioned in my previous post linked to the expansion of maize farming in Central and South America.
The paper analyzed in that post stated that maize agriculture spread into South America with dogs and that there were no dogs in that region before the invention of agriculture, the suggest that the evidence supports that "the spread of agriculture" introduced dogs into South America, and does not support the notion "hat dogs were introduced during the initial peopling of South America by hunter–gatherers...This dispersal happened in a context of early agrarian societies" some 7,000 years BP.
This scenario implies two possibilities:
- The first wave that peopled South America, 20,000 or more years ago did so before dogs evolved in Eurasia, so of course the didn't bring any dogs into America when they migrated. This first wave of Paleoindians was swamped by a later wave (see this post), and the dogs that they brought with them occupied a vacant niche.
- Dogs are older than we think, maybe 50 or 70,000 years old (we don't have proof of this, however, a 2023 paper pushes the dog-domestication date back to 40,000 years ago. So, the first wave into America brought dogs, they were adapted to the hunter-gatherer lifesytle of these First People. When farming reached South America, farmers replaced the original human population there, and the second wave of dogs did displaced the dogs of the first wave, which could not digest carbohydrates.
Interestingly, a study reported that a now extinct canid (Dusicyon avus) could produce fertile offspring if mating with domestic dogs. This could explain their extinction some 400 years ago, with successive matings with domestic dogs watering down the D. avus until their genetic pool was lost. However, the authors believe that even though hybridization could have played a role in their extinction, it was caused by the effects of the Europeans on the environment and habitat that led to their demise.
Coincidentially, 400 years ago, the Europeans began displacing the Natives, and this altered their relationship with the environement, as they moved further from the European settlements. Another factor, observed in Patagonia, was that the Natives adopted the more docile domestic dogs introduced by the Spaniards. This verly likely pushed their domesticated foxes into decline, and ultimately, extinction.
This paper also found that an D. avus specimen they studied, called CS/91, shared the diet of the humans with which it interacted: "the diet of the CS/91 canid varied from that of other wild carnivores in the region, pointing to a higher intake of C4 resources (probably maize) and a higher distinct trophic level. Furthermore, the isotopic results of CS/91-1 are more similar to the values obtained from adult humans found in the same archaeological context."
It mentions that the CS/91-1 specimen was found in the same burial with human remains:
"it is possible that the fox was intentionally inhumated in this burial context, becoming the first record of a complete skeleton of this fox species buried alongside humans. The co-burial of humans and foxes is a rare archaeological record worldwide and suggests a cultural or symbolic significance. Although the reasons for its inclusion in a mortuary context remain unclear, the most plausible explanation is that this fox was a valuable companion to the hunter-gatherer groups. Its strong bond with human individuals during its life would have been the primary factor for its placement as a grave good after the death of its owners or the people with whom it interacted.
The stable isotope analysis of carbon and nitrogen further supports this interpretation, revealing a similar dietary pattern between CS/91 and the human individuals found in the same archaeological context rather than a typical carnivorous diet. In other words, the hunter-gatherers fully incorporated this wild animal into their ecological and cultural niche, possibly through systematic feeding."
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2025 by Austin Whittall ©
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