BALTIMORE (WJZ) — For many dog owners, it seems like their pet has just the right look that’ll break any human into giving them what they want. A new study says that dogs don’t just use the “sad puppy eyes” on their masters, they have a whole selection of facial expressions they save just for communicating with humans.

Researchers at the University of Portsmouth in England say dogs present more facial gestures when human are paying attention to them than they do when they’re alone. The scientists add that expressions like raising their eyebrows and making their eyes appear bigger are all signals that our furry friends are trying to communicate. “Facial expression is often seen as something that is very emotionally driven and is very fixed, and so it isn’t something that animals can change depending on their circumstances,” said Professor Bridget Waller, via The Guardian.

The study, published in Scientific Reports, followed 24 dogs as they interacted or were being ignored by humans. A frame-by-frame comparison of the animals found that they were far more likely to show their tongue and raise eyebrows when they were face-to-face with a person. The scientists’ theory about dogs communicating was bolstered by the fact that the dogs’ expressions didn’t change drastically when they received food.

“We wanted to see if dogs would produce the most facial expressions when they saw the face and the food, because that might then tell us they are trying to intentionally manipulate the human in order to get the food – and we didn’t see that,” Professor Waller added. The U.K. team said the study shows how dogs have evolved over centuries of domestication and are learning to “talk” to their caregivers. “I think this adds to a growing body of evidence that dogs are sensitive to our attention,” said researcher Juliane Kaminski.

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