Puppy Dog Eyes Evolution - This diagram provided by Tim Smith in June 2019 …
This diagram provided by Tim Smith in June 2019 shows a comparison between dog and wolf facial muscles. A study released on Monday, June 17, 2019 suggests that over thousands of years of dog domestication, people preferred dogs that could pull off the ”puppy dog” eyes look. And that encouraged the evolution of the facial muscle behind it, researchers propose. (Tim Smith via AP)