Scientists Closer to Understanding Animal Facial Expressions

The challenge all veterinarians face is that their patients cannot speak to them, and so they must rely on clinical signs and owner reports of pet behavior to determine how the animal might be feeling. But scientists are finally starting to be able to understand and read the facial expressions of animals.

Researchers are developing specific coding systems that would enable them to read the facial expressions of animals.

The system would describe each facial feature change—such as an eye squint or pursed lip—and associate it with a particular emotion or physical feeling.

Then, by looking at photographs and scoring how much each of these facial features change, researchers can also determine how strongly each emotion is felt by the animal.

To date, only pain coding systems available for nonprimate animals, called grimace scales, have been developed. Mice, rats, rabbits, horses, and sheep have all been shown to have similar facial expressions when experiencing pain, which can be measured with grimace scales.

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Grimace scales were formulated to improve the welfare of animals used in laboratories or for food products. This new coding system is being formulated so veterinarians and pet owners can help reduce pain, boredom, and fear in animals while also generating more joy and curiosity for them.

Mirjam Guesgen, postdoctoral fellow in animal welfare at the University of Alberta, believes that a smart phone app for reading animal emotions could be possible down the line. “One day, pet owners, farmhands, or veterinarians could hold up a smart phone to a dog, sheep, or cat and have an app tell them the specific emotion the animal is showing,” she said.

Guesgen believes this automated system will require many steps, though. First, emotions need to be defined in a testable, non—species-specific way. Then, descriptive baseline data must be gathered about emotional expression. Last, these data need to be turned into a technological system.

While this automated system may be far out into the future, great progress is still being made when it comes to better understanding what emotions animals express and how they express them.