The dance-based communication system used by honeybees is one of the most fascinating, complex and highly celebrated communication systems in the animal world. Known as the ‘waggle dance’, it is a figure of eight-like movement, the duration and orientation of which correspond to the spatial coordinates of a high-quality resource. “Honeybees use this dance to provide the colony with essential information about the location of, for example, blooming trees,” says Elli Leadbeater, a professor of Ecology and Evolution at Royal Holloway University of London. “The fact that other foraging bees use this information to locate the indicated site remains one of the most astounding discoveries in animal behaviour.” But how do bee brains process this complex information, and is this capability the result of evolution or learning? These are the questions that the EU-funded BeeDanceGap project set out to answer.
Dance dance evolution
According to Leadbeater, who coordinated the European Research Council supported project, honeybee hives are microcosms of information sharing. “In the hive, foragers receive information on food sources via dance behaviour, olfaction, and nectar sharing,” she explains. However, because all this communication happens simultaneously, researchers have never been able to identify which pathway is key in driving bees to food. “Although we knew that bees could use the dance, we didn’t know when they used it and when they used the other systems,” adds Leadbeater. The project overcame this hurdle using a network-based diffusion analysis (NBDA) method that could identify the specific types of information the honeybees were responding to. The method assumes that if a particular piece of information is spread through social learning or communication, then it will follow the connections of a social network. Using the NBDA method, researchers demonstrated that, when it comes to communicating about new food sources, dance communication is the dominant pathway. However, when it comes to food sources that the colony already knows about, then olfaction is the most important pathway, with the waggle dance being almost completely ignored. “Biologically, this is an important finding because it explains one of the key features of the honeybee niche that may have driven the evolution of the dance – the need to rapidly shift to new food resources,” remarks Leadbeater.
Shedding new light on the waggle dance
The project’s research was conducted from Royal Holloway University of London’s Insect Cognition Lab, an area surrounded by suburban gardens. Although a lovely area – and one ideal for a healthy honeybee population – it raised some unique challenges for Leadbeater’s team. “It seems honeybees prefer the abundant natural sources of food over our feeders,” she says. “This meant we had to fit all our research into an 8-week period when most flowers die, and our feeders become more appealing.” Despite these minor setbacks, the project succeeded in shedding new light on the honeybee waggle dance. “Although this behaviour has been studied for nearly a century, no one has found a way to identify the circumstances under which bees rely on the dance,” concludes Leadbeater. “Thanks to the BeeDanceGap project, this is no longer the case.” The project’s NBDA method, which is applicable to the study of any animal group, is available via the project’s website.
BeeDanceGap, honeybee, honeybees, communication, animal world, animal behaviour, waggle dance, bees, hive, network-based diffusion analysis, NBDA