Dance like nobody's watching? Not quite, at least not for honey bees.
In recent years, scientists have carefully deciphered details of the honey bee " waggle dance ," which is an advanced form of social communication in the animal kingdom. University of California San Diego biologists and their international colleagues recently unraveled how the dance conveys critical information about food sources for the benefit of fellow hive inhabitants.
A new study on the dynamics of the dance, published in the Proceedings of the National Academy of Sciences, finds that it's not just the dance performer that matters — it's also who's in the audience. The experiments showed that the performing forager is not simply broadcasting a predetermined message. Rather, the precision of the performer's directions to the food source depends on its audience.
Once a foraging bee returns to the hive after discovering a promising food source, it communicates this vital location information to hive mates by performing a blazing-fast, complex dance. While nestmates pay attention, the dancing forager runs forward while "waggling" its abdomen, then loops back and repeats the performance in a matter of seconds. The angle of the waggle dance conveys the direction of the food relative to the sun, and the duration of the performance encodes the distance to the source.
Professor James Nieh of the UC San Diego School of Biological Sciences likens the new findings to a street performance. With a good-sized audience, street musicians focus on the performance itself. But when the crowd thins, the performer scans faces, shifts position and puts more effort into finding and keeping an audience. The search for a receptive audience essentially changes the bee's performance because it is difficult to maintain the precision of a fast, repeated movement pattern while simultaneously moving around to locate and engage an audience.
"Everyone has seen a street musician or a performer adjust to a changing crowd," said Nieh, a faculty member in the Department of Ecology, Behavior and Evolution. "In the hive, we see a comparable tradeoff. When fewer bees follow, dancers move more as they search for their audience, and the dance becomes less precise."
Working with scientists at the Chinese Academy of Sciences and Queen Mary University of London, Nieh studied experimental hives and monitored the honey bee "dance floor," which replicated the crowded, dynamic social space found in real hives. In the first part of the experiment, they evaluated fluctuating numbers of bees in the primary dancing area to test the changes caused by different audience sizes. In a second set of experiments, they held the number of bees constant, but changed the age of the audience members by introducing young worker bees, which are not interested in following dances. In both experimental scenarios, dancers were less precise when performing for a smaller audience.
"The waggle dance is often presented as a one-way information transfer," said Ken Tan, the senior author of the study and a researcher at the Xishuangbanna Tropical Botanical Garden of the Chinese Academy of Sciences. "Our data show that feedback from the audience shapes the signal itself. In that sense, the dancer is not only sending information, but also responding to social conditions on the dance floor."
The new study also provided clues to how dancers sense audience size and composition. Audience members, they found, make frequent antennal and body contact with dancers. Such tactile cues likely provide information about audience composition.
Lars Chittka, a researcher at Queen Mary University of London, said the study shows that "humans aren't the only ones who perform differently depending on their audience. Our study shows that honey bees quite literally dance better when they know someone is watching. When followers are scarce, dancers wander around searching for listeners — and in doing so, their signals become fuzzier. It's a lovely reminder that even in the miniature world of insects, communication is a deeply social affair."
Apart from honey bees, the new research results offer a window into how animal groups manage information. Collective groups of animals often depend on signals that must be repeated, shared and acted upon.
"The new findings show that the accuracy of a signal can depend on the availability of receivers, not only on the motivation of the sender," said Nieh. "That kind of feedback may be important in animal societies, engineered swarms and other distributed systems where the quality of information can rise or fall with audience dynamics."
The study's researchers include: Tao Lin, Shihao Dong, Gaoying Gu, Fu Zhang, Xiuchuan Ye, Tianyi Wang, Ziqi Wang, Jianjun Li, James C. Nieh, Lars Chittka and Ken Tan.
Funding for the study was provided by the 14th Five-Year Plan of Xishuangbanna Tropical Botanical Garden; Chinese Academy of Sciences (E3ZKFF3B); the Yunnan Revitalization Talents Support Plan (XDYC-QNRC-2023-0566); and National Natural Science Foundation of China (32571753 and 32322051).
