Mutation That Gave Us Tiny Dogs Found in Ancient Wolves
From smithsonianmag.com:
Looking at a snorting French bulldog or a prancing Pomeranian it can be hard to grasp how these pint-sized pooches could have possibly descended from wolves, which today routinely exceed 100 pounds and can take down bison.
Given the huge size difference between wolves and the littlest dogs, it’s easy to assume the genetic changes that brought about the supreme smallness of Chihuahuas and their ilk only appeared as humans started domesticating dogs, about 15,000 years ago.
