Paper Wasp - Facial Recognition

Facial Recognition

Recent research has discovered paper wasps have face recognition abilities comparable to humans. One recent study conducted at the University of Michigan in Ann Arbor showed paper wasps have the same facial recognition abilities common to humans or chimps.

"Faces are extremely important to species such as humans", said the study coauthor Michael Sheehan, a Ph.D. candidate at the university. "Studies show that when you look at a face, your brain treats it in a totally different way than it does other images," he said. "It's just the way the brain processes the image of a face, and it turns out that these paper wasps do the same thing."

The study consisted of a series of tests on the Polistes fuscatus species of paper wasp. This particular species is unique in that it has extremely variable facial patterns from member to member. Sheehan and evolutionary biologist Elizabeth Tibbetts placed individual wasps into a T-shaped maze, with one image shown at each end of the top T arm. Images varied from caterpillars, simple geometric patterns, and computer-altered wasp faces to pictures of a genuine paper wasp faces. These images were interchanged randomly during testing.

According to Sheehan, whenever the wasp in the maze chose the side of the T arm with the correct picture, it would get a reward, in this case a safety zone. Though images were always changed, "one particular image was always associated with the safety zone," Sheehan explained. Once the wasps associated the right image with the safety zone, they were able to choose the correct image and thus get to the safety zone essentially every time after. This suggests that the paper wasps' brains are tuned to recognize faces of their own species -- as with humans.

"Wasps and humans have independently evolved similar and very specialized face-learning mechanisms, despite the fact that everything about the way we see and the way our brains are structured is different," Sheehan said. "That's surprising and sort of bizarre." The unique, distinct faces of paper wasps, as well as the wasps' ability to recognize and remember each other's faces, are likely tied to the insects' multicolony social structure, Sheehan added. "They have multiple queens and they all want to reproduce—they all want to be the most dominant. So being able to recognize each other helps them understand who's already beaten who, who has higher ranking in the hierarchy, and this helps to keep the peace."