We have likely all observed paper wasps building umbrella-shaped nests and flying to and fro gathering food (e.g., caterpillars, spiders) for their young. They all look the same, and they are all part of a single-minded “hive” mentality…right? On the contrary, investigations into some wasp species have shown that some wasp species treat each other as individuals. Some wasps may be treated differently than other wasps, depending, in part, on the color patterns of their face.
Why is facial recognition important to some wasp species?
The Northern paper wasp, Polistes fuscatus, is orange and black, and the facial features of this insect are unique for individuals of this species. Related female wasps generally initiate new nests or move into abandoned nests, hence cooperation is important for these wasps. The ability to easily recognize nest mates reduces aggression and improves cooperation. When researchers challenged the wasps to identify nest mates without antennae and/or with altered (i.e., using paint) facial patterns, recognition happened at a slower pace (Sheehan and Tibbetts 2011).
In Polistes dominulus (“European paper wasp”), facial patterns are related to size and (potentially) dominance. This may impact conflicts between wasps. For this wasp species, an increased number of facial spots indicates dominance, while a uniformly colored face (no spots) indicates a reduction in dominance (Tibbetts and Lindsay 2008). The same study showed that wasps with a lot of facial spots were avoided, hence facial patterns indicating dominance status is a way that wasps can avoid aggression. This was shown in a laboratory setting where wasps were more likely to choose food that was guarded by another wasp with facial patterns indicating low dominance status, compared to guards having patterns indicating high dominance. This could be a way for wasps to consider their potential rivals without engaging in a fight. In general, queen wasps are larger and have spottier facial patterns than worker wasps, hence this is related to their dominance status.
Other Uses for Visual Cues in Paper Wasps
Female paper wasps can also use visual cues to choose a suitable mate. The amount of black coloration on the head/face of the male, the appearance of yellow spots on the abdomen, and large body size impact a female wasp choosing a male as a mate. Researchers have shown that males (Polistes simillimus – Neotropical paper wasp) with more black coloration on the head are chosen as mates by females more often than males with low amounts of black on the head (Rodrigues de Souza et al. 2014). The same study showed that larger male body size was not a determinant of female mate selection. However, the interaction of the spot shape index (width, height, and area of spots on abdomen) and amount of black coloration on the male head influenced females selecting them as mates.
Do all paper wasp species use facial recognition to recognize nest mates?
Some species of paper wasps are solitary (e.g., Polistes metricus) and create new nests on their own. These wasps do not have distinct variability in facial patterns and do not recognize others of the same species as individuals (Sheehan and Tibbetts 2011). In this and other wasp species with reduced variability in facial patterns, these patterns may play a lesser role in social interactions.
It is possible that larger wasps have greater visual acuity and this may be related to improved facial recognition and communication. Studies are ongoing to determine how some wasp species carry out this facial recognition activity of visual communication and why it varies between species. Face to face interactions of paper wasps are common (aggressive and sexual purposes), hence visual communication is important for these insects. The compound eye structure of paper wasps show good acuity up close so that they can see pattern and coloration differences.
Perhaps humans could use this knowledge of wasp visual cues to help avoid wasp exposure in certain situations; however, more research is needed to determine the practical application of this knowledge on paper wasp visual recognition.
de Souza AR, Alberto Mourão Junior C, Santos do Nascimento F, Lino-Neto J (2014) Sexy Faces in a Male Paper Wasp. PLoS ONE 9(5): e98172. doi:10.
Sheehan MJ and EA Tibbetts (2011) Specialized face learning is associated with individual recognition in paper wasps. Science 334:1272-1275.
Tibbets EA and R Lindsay (2008) Visual signs of status and rival assessment in Polistes dominulus. Biology Letters 4:237-239.
Tibbets EA and J Dale (2004) A socially enforced signal of quality in a paper wasp. Nature 432:218-222.