Artificial intelligence could eventually help us understand when animals are in pain or showing other emotions — at least according to researchers recently profiled in Science.

For example, there’s the Intellipig system being developed by scientists at the University of the West of England Bristol and Scotland’s Rural College, which examines photos of pigs’ faces and notifies farmers if there are signs of pain, sickness, or emotional distress.

And a team at the University of Haifa — one behind facial recognition software that’s already been used to help people find lost dogs — is now training AI to identify signs of discomfort on their faces, which share 38% of facial movements with humans.

These systems rely on human beings to do the initial work of identifying the meanings of different animal behaviors (usually based on long observation of animals in various situations). But recently, a researcher at the University of São Paulo experimented with using photos of horses’ faces before and after surgery and before and after they took painkillers — training an AI system to focus on their eyes, ears and mouths — and says it was able to learn on its own what signs might indicate pain with an 88% success rate.