You would think that only the most advanced mammals would be able to recognize faces. Studies have shown that both macaques and sheep are capable of recognizing other members of their animal family based on particular facial features. As you can imagine, the ability to recognize faces is extremely rare in the insect world. In fact, only a few different species of paper wasps are able to detect the faces of others. For a long while scientists could not explain how certain wasps could discern different faces. However, a group of researchers has recently gained a better understanding about the physiological mechanisms that allow wasps to recognize faces. 
The team of researchers studying facial recognition in wasps focused on the genes involved in pattern recognition, and facial recognition. Researchers started by training one group of wasps to recognize patterns, and the other group was trained to recognize faces. While the wasps were indulging in pattern and facial recognition activities, researchers analyzed how different genes involved with recognition were expressed. The researchers quickly found that the gene-expression patterns involved with facial and pattern recognition differed greatly. Researchers believe that the gene-expression patterns involved with facial recognition are different from other types of recognition because facial recognition could be a part of a more complex social behavior.
According to Elizabeth Tibbetts, an evolutionary biologist at the University of Michigan, and coauthor of the study, some wasp species can recognize faces more easily than any other form of visual stimuli. Based on previous studies, one group of paper wasps use facial recognition when forming social hierarchies within a colony. The leaders of a colony would rely on facial recognition in order to apply dominance to particular members of the colony. This finding shows that some species of paper wasps use facial recognition when building and maintaining order within a colony. Therefore, the ability to recognize faces of other wasps is likely a far more primitive part of the paper wasp’s behavior than initially thought.
Do you believe that a paper wasp’s ability to recognize faces is only useful during social situations involving paper wasps?
