When it comes to dogs, the jury is still out on whether we domesticated dogs or they domesticated us. Remember that, dogs are not tame or domesticated wolves as they separated from the niche they shared with wolves through a common ancestor approximately 50,000 years ago to become today’s dog.
Canine bones were discovered in Taimyr Peninsula, Siberia. Whole genome sequencing indicates that the dog, the gray wolf and the extinct Taymyr wolf diverged at around the same time 27,000–50,000 years ago and Proto-dog did not become wolves. The domestic dog evolved in a totally different environment than the wolf.
The emergence of man’s best friend was pretty straightforward. The first dogs descended from wolves in Europe (the extinct Taymyr wolf) and it was revealed that the Taimyr wolf’s genome was equally related to both dogs and wolves. Humans domesticated those proto-dogs, or they domesticated humans, until the eventual animal known as a “dog” had many of the traits we associated with the animal today.
The beautiful thing about science is that it is self correcting, marches forward, and today’s science seems to support the theory that dogs approached humans first, creating a symbiotic relationship with us that contributed to the survival of both species.
When we evolved from hunter/gatherers to farming and started storing our grain, rats and mice invaded and cats came along. This happened much later than the domestication of dogs, about 5,500 years ago, when cats approached humans due to their food source and humans recognized the potential for an equally positive symbiotic relationship. It helped that the cats were friendly and open to human relationships.
This process is what scientists call a “commensal” pathway to domestication. Unlike cows or sheep, which evolved from wild animals that humans hunted, dogs and cats came into a mutually beneficial relationship with humans through food. Nothing about the process was intentional; no human set out to try to domesticate a cat or a dog and make it into a pet, but a chain reaction was set off by a human practice, and one thing led to another, and our pets today are the result.
Further research suggests that that European dog is not the ancestor of all our dogs; instead, every modern Western dog hails from a Southeast Asian progenitor lineage. According to research conducted by Ben Sacks from the University of California at Davis and his colleagues, the Southeast Asian dogs prospered because, after they were brought south of the Yangtze River some 6,000 years ago, they were separated from wolves. Without that proximity, the Southeast Asian dogs could no longer interbreed with wolves, and thus followed their own evolutionary path.
Now let’s throw a wrench into that whole scenario.
Extremely well preserved, prehistoric canine fossils are shedding light on dog and wolf ancestors from 2 million years ago.
The fossils, described in the latest issue of the Journal of Mammalian Evolution, date to that early period and belonged to a canine carnivore known as Canis etruscus that lived near Rome, Italy. It looked like a cross between a German shepherd and a wolf.
“Canis etruscus appeared approximately 2 million years ago and is the oldest European species referred to in the genus Canis,” lead author Marco Cherin told Discovery News, adding that this species “was considerably smaller than the modern wolf.”
“We can suppose that it was a social dog, as most of the living species of similar size,” continued Cherin, who is a researcher at Perugia University’s Department of Earth Sciences. “Hunting in packs, Canis etruscus could have preyed on small to medium-sized animals.”
This apparent ancestor of all dogs in Europe likely gave rise to another member of the dog/wolf family tree, Canis mosbachensis, about 1 million years ago. Canis mosbachensis, in turn, is considered to be a direct ancestor of modern wolves.