Puppy dog eyes' are a real thing, researchers say dogs can alter their facial expressions

Most everyone has fallen for the heartwarming "puppy dog eyes" expression of an adorable (or not so adorable) pooch.

You know the look. It's the one where the pup lifts his brow, his eyes get bigger, and the next thing you know, you're tossing him the steak off your dinner plate.

Until now, there wasn't proof that dogs have the ability to invoke facial expressions as a way to communicate with humans. A study by researchers at the University of Portsmouth in England, shows how sensitive dogs are to human attention.

The study's lead researcher, psychologist Juliane Kaminski, told Nature it also provides the first evidence in a non-primate species that facial expressions can be used actively to communicate. The full study was published Thursday in Scientific Reports.

Previously, researchers assumed such expressions are an involuntary reflection of an animal’s emotional state, according to Nature's report.

What were the study's findings?

● Dogs produced significantly more facial movements when they were being watched than when not, reported the Daily Mail.

● Dogs also increased the frequency of certain expressions, based on the attention they receive.

● One movement AU101, what we would call "puppy dog eyes," was used by dogs with greater frequency when being watched by a person. This movement has been shown in previous research to result in dogs in shelters being rehoused more quickly.

● Researchers believe increases in the use of this expression demonstrates an awareness on the part of dogs of the benefits it can bring.

● Researchers argue that their data points to a more flexible system in dogs, which combines both emotional and potentially cognitive processes.

How was the study conducted?

●  Kaminksi and her colleagues studied 24 pet dogs of various breeds (including 10 mongrels) and ages (from 1 to 12 years). Each dog was tied with a lead in a quiet room, with a video camera trained on its face. An experimenter, to whom the dog had been introduced, stood a meter away, Nature reported.

● The person adopted four different positions, in turn: 1. facing the dog and displaying food in her hands; 2. facing it and not displaying food; 3. facing away from the dog and displaying food; and 4. facing away and not displaying food. Throughout, she tried to keep her gaze focused on a spot on the wall, and did not respond to the dog’s behaviors.

●  All the dogs completed two trials, on separate days.

● The dog's facial expressions were analysed by the Dog Cognition Centre’s Bridget Waller, using a system she helped to create, called DogFACS. It is based on the Facial Action Coding System for people, which identifies observable facial changes associated with underlying muscle movements.

What does all this mean?

Basically, it shows that dogs are sensitive to human interaction and have the ability to manipulate their facial expressions in an effort to communicate with us.