By Sarah B. Weir & Trystan L. Bass
More from Green Picks blog
Pavlov might have called that contented look on a dog's face a collection of conditioned reflexes, but now science is catching up with what animal lovers have always known.
According to Professor Nicholas Dodman, head of animal behavior at the Cummings School of Veterinary Medicine at Tufts School of Medicine, until recently, scientists have generally underestimated the emotional range of animals. Dodman says that today it is widely accepted that mammals do experience primary emotions such as fear, sadness, anger, and happiness and perhaps even some secondary emotions like jealously. He points out that your pet might not understand the exact details of your hard day, but is sensitive enough to curl up and listen.
We can't be sure if the animals pictured here are truly smiling, but looking at them may make you smile.