The Hunting Symbiosis Model of Dog Domestication

 

A lot of discussion about dog domestication is a debate between the scavenger vs. the hunting-symbiosis model.

  I don't think the scavenging model is well-supported from the empirical reality of when it appears dogs where domesticated.  Virtually all genetic data supports a domestication of the dog thousands of years before humans engaged in agriculture. Agricultural society currently has created a surplus where things like coyotes, raccoons, red foxes, and even some wolf populations engage in widespread scavenging of our waste. Hunter-gatherers simply didn't have enough food waste to feed scavenging wolves that could somehow evolve into dogs.

There have been some attempts in the past month to make this model viable again.  A paper was recently published in Nature that points out that humans have a very hard time digesting excess protein from their kills. Humans require fat from meat to power our freakishly large brains, but excess protein is a real problem for us. The authors contend that wolves would have scavenged the lean cuts of meat, and humans would have eaten the fattier ones.

Thus, because humans and wolves would have preferred different parts of the animal, humans would have created a glut of waste in lean meat, which the wolves would have devoured. 

I think this is still a bit of stretch, and I think it points more toward the hunting-symbiosis model of dog domestication. 

The fact that humans and wolves would have preferred different parts of the animal shows how this symbiosis could have been maintained much more easily than the fanciful notion that people were leaving garbage heaps of lean meat cuts.

I think the story of dog domestication began with a long-term relationship between wolves and people. I think it may have gone something like this: 

Wolves often test ungulate prey. Generally if prey is healthy, it stands and faces the wolves. If it is not healthy, it runs, and the wolves run it down and kill it. 

Healthy animals are likely to have good amounts of fat on them, which hunting humans would need to power their brains, but healthy animals are by definition hard to kill.

Wolves harrying and testing quarry, which do two things for these hunters. When the quarry stands to face the wolves, it becomes distracted and more stationary-- and much easier to hit with a thrown spear. The health of the animal that would give it it the guts to stand and face the wolves would make it more vulnerable. 

This way of hunting with wolves is suggested in Pat Shipman's The Invaders.  She contends that European hunters would use wolves to bay up mammoths, distracting them them the human approach and making them easier to kill. 

This hunting technique is not at all dissimilar to how Scandinavian hunters use elkhounds. The dogs distract the large cervids (better known to North Americans as moose). The distracted and mostly stationary moose is then more easily taken with a rifle. 

That humans have a hard time digesting and metabolizing lean protein actually points more towards the hunting symbiosis model for dog domestication, a idea explored more thoroughly in Pierotti and Fogg's First Domestication. 

Wolves and ravens have been observed cooperatively hunting together. The ravens will search from the sky, looking for a weakened moose or caribou. The wolves then kill the weakened animal, and both the wolves and ravens get a chance at the kill.

It makes sense that wolves, which had not yet undergone the brutal selection that agricultural and industrial man performed upon the species in more recent centuries, would have been more than willing to engage humans in the same way. And humans would have found this method of hunting was a great way to get fatty meat very easily.

So it makes sense that humans and wolves could have worked together, perhaps for tens of thousands of years, until there was ever a discernable creature that we might call a dog.

The antiquity of dogs means we are forced to consider that cooperative hunting played a vital role in their evolution and eventual domestication.

To do otherwise is engage in a sort of logical gymnastics that makes one look quite a bit foolish.

So it began with bay dogs in a world of ice and snow.

The Last Glacial Maximum Played a Major Role in Dog Domestication.

Indigenous siberian with a laika. This is not a Native American with a Native American dog. However, a new study reveals that Siberia could be the point of origin for the domestic dog. It also the first dogs
 in the Americas came with Siberian hunter-gatherers 15,000 years ago.
 

A new study  released in PNAS today revealed that dogs were domesticated around 23,000 years ago in Siberia. This study, which looked at ancient DNA from dogs and humans from Eurasia and North America, revealed that Siberia is likely the point of origin for dog domestication. Further, the authors were able to demonstrate that ancient North America dogs derive from this Siberian population, entering North America around 15,000 years ago, which is roughly the same time that the first humans entered the continent.

The authors contend that 23,000 years ago roughly coincides with the last glacial maximum, which could have put increased pressure on humans and the wolves that led to dogs to form the relationships that eventually gave rise to domestic dogs. 

The findings of this study are pretty unique, because they come from a pretty well-designed analysis of ancient dog remains. And there is comparison to human dispersal in the late Pleistocene.

A 2013 study in PLOS One revealed that the remains of a 33,000-year-old canid from a cave in the Altai mountains was a dog, and this creature was closely related to the ancient American domestic dogs.

These findings seem to be somewhat contradictory, and I think we need to be careful in assuming that the origin for the domestic dog has somehow been find at long last.

It is possible that the authors are picking up on in the new study is the role the last glacial maximum played in creating a distinct dog lineage.

Mark Derr in his book How the Dog Became the Dog posits that the last glacial maximum was instrumental in creating the distinct "dog" morphology in domesticated wolves, but it is very possible- and it is pretty likely-- that ancient humans had a relationship with wolves going back deeper than the 23,000 years posited in the study.

Indeed, the authors of the new study point out that the last glacial maximum could have isolated these wolves from other wolves, allowing for a more rigorous selection for great symbiosis with humans.

This idea is quite intriguing, because it is very likely that human and wolf relationships in Eurasia go much deeper than the ones that ultimately lead to dog domestication as we know it now. For example, we have several examples of ancient European "dogs" that date to around 31,000 years ago, including one in what is now the Czech Republic that was apparently interred with a bone in its mouth.

So it is very possible that the lineage of wolves that became modern dog lineages was finally made distinct from other gray wolves 23,000 years ago, but we likely have several periods of domestication and semi-domestication that stretch across Eurasia for thousands of years before the last glacial maximum. Some of these domesticated and semi-domesticated wolves could have rejoined the wild population, and wild genes could always be filtering in. 

The truth of the matter is that after reading Pierotti and Fogg's wonderful book on dog domestication, one wonders if we will ever know when dogs became distinct from wolves. But it would be reasonable that the last glacial maximum could have played a role in that transition.