In a study published in PNAS, researchers from the Xishuangbanna Tropical Botanical Garden (XTBG) of the Chinese Academy of Sciences, Freie Universit？t Berlin and Rutgers University showed that the dance of the returning honeybee forager conveys the direction and distance of the food source from the hive to the honeycomb surface, a kind of map—a representation of where the food source is.
The dance communication is much richer than previously thought, decoding the vector information into a map-like representation of the explored space, according to the researchers.
Honeybees (Apis mellifera carnica) are the only non-human animals that communicate navigational information through a symbolic form of information transfer. Successful returning foragers perform a waggle dance to indicate the direction and distance of the food. However, the possibility that the interpretation of the dance refers to stored terrain information had not been previously considered, let alone experimentally demonstrated.
In this study, the researchers introduced a new method in which bees have no feeder experience recruited by dancing bees, were captured and transported to release sites far from the hive before flying the vector flight, rendering the flight instruction they received from the waggle dance worse than useless. However, most of the recruited bees sooner or later gravitated toward the true location of the food source.
“The courses taken by the displaced recruits towards the food satisfy the operational definition of a map: A representation of the spatial relationships between mapped objects (possibly including the horizon profiles) that allows a navigator to set a course to any location within the map’s frame of reference from any other location within that frame of reference,” said Dr. WANG Zhengwei, first author of the study.
The symbols used (body movements in the dark hive on a vertical comb surface) are rather simple, but they allow the receiving bee to derive a representation of the target location. Because foraging bees frequently switch between dancing and dance following, thus the dance message is not just a flight instruction; it is part of a navigational conversation about where the food is and how to get to there.
“Our results add new information to the understanding of symbolic communication through the waggle dance. By following the dance, recruits receive two messages, a polar flight instruction (bearing and distance from the hive) and a Cartesian-location vector that allows them to approach the source from anywhere in their familiar territory,” said WANG.
WANG Zhengwei Ph.D
Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China
A honey bee is sucking on flower. (Image by WANG Zhengwei)
Honey bees are sucking on flower. (Image by WANG Zhengwei)