At first blush, the emergence of man's best friend is pretty straightforward. The first dogs descended from wolves in Europe about 14,000 years ago. Then humans domesticated those proto-dogs until the eventual animal known as a "dog" had many of the traits we associated with the animal today. That much of the evolutionary history of the modern dog has been clearly understood. But 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. Why? Why did some upstart Southeast Asian lineage triumph, even in Europe, instead of the endemic European one? Turns out, it might have to do with your pet dog's affinity for Cheetos.