Honey Bee Medicine for the Veterinary Practitioner. Группа авторов
movement pattern on the vertical surface of the comb in the darkness of the colony often near the hive entrance (Figure 4.2). The honey bee first performs a straight waggle run followed by alternating right and left loops returning to the starting point, another waggle run, and so on (Seeley 1995). During the waggle run, the dancing bee shakes her abdomen back and forth while also vibrating her wings; the duration of the waggle run and dance tempo speaks for the distance to the flowers, and the direction of the waggle run on the vertical comb of the hive relative to gravity symbolizes the direction to the flowers with respect to relative position of the sun, or solar azimuth angle (Winston 1987; Seeley 1995; Tsujiuchi et al. 2007). Further, an increasing intensity of dancing behavior and length of dance performance within the hive communicates a higher quality food resource (Winston 1987). Other signals involving pheromones, tactile contact, dance sounds, comb vibrations, and temperature are also thought to be conveyed during the waggle dance. Even though much has been revealed about how this remarkable dance communication is achieved, mysteries still remain (Thom et al. 2007; Tsujiuchi et al. 2007).
Figure 4.2 Physical communication in the honey bee using the Waggle Dance. The waggle dance occurs when a foraging bee returns to the hive and shares information on a food source; the bee performs a figure‐8 dance on the vertical comb near the hive entrance. The center of the dance pattern signifies the direction, distance, and quality of the food source with reference to the sun (Winston 1987; Seeley 2010). Direction: on the left side of the diagram the flower food source is located directly in the path of the sun, and the bee waggles straight upward toward the top of the hive indicating the food source is directly in line with the sun. On the right side of the diagram, the food source is at an angle of 150 ° to the left of the vertical axis of the hive, and this tells the surrounding observing bees that the food source is located in a direction 150 ° to the left of the solar azimuth. Distance: the distance to the food source is specified by the duration of the waggle dance – approximately one second of body waggle symbolizes 1000 m of flight (Seeley 2010). Quality: the quality of the food source is indicated by the intensity and longevity of the waggle dance (Winston 1987).
Source: © Lauren D. Sawchyn, DVM, CMI. Chapter: Physiology of the honey bee, authored by Rolfe M Radcliffe and illustrated by Lauren D. Sawchyn.
Tremble Dance
Another dancing behavior also recognized by Karl von Frisch long ago was the tremble dance. He described the dance as a strange behavior – a neurosis – where the bees run about the combs making constant trembling movements of their bodies, similar to the disease known as St. Vitus' dance or chorea, but von Frisch was not able to identify its significance (Seeley 1995). The tremble dance is a long signal, persisting approximately 30 minutes, occurring throughout the broodnest portion of the hive. Seeley later deciphered its meaning, discovering that the tremble dance was used by foragers to recruit more nectar processing bees when a nectar flow results in increased nectar arriving at the hive without enough bees to help unload the food source (Seeley 1992). In a clever experiment Seeley switched the dancing behavior of foraging bees from performing the waggle to the tremble dance by only changing one variable: how long it takes for a foraging bee to unload its nectar resource. When a foraging bee experienced a search time of 20 seconds or less to find a food storing bee to unload its nectar, she performed the waggle dance, whereas a search time of 50 seconds or more resulted in the tremble dance (Seeley 1992). Through this work, Seeley and others determined that the tremble dance had multiple meanings: it stimulates a shift to processing nectar for bees working inside the hive, and to stop recruiting additional foragers for bees gathering nectar outside the hive. The waggle and tremble dances of foraging bees are now known to be complementary behaviors working in concert to keep a colony's rate of nectar collecting and processing balanced (Seeley 1995).
Shaking Dance
The shaking dance or signal is yet another method of communication performed by foraging worker bees and helps foragers increase the number of bees in a colony engaged in foraging during a rise in nectar supply or a high demand for food or both (Seeley 1995). A returning honey bee forager will perform this dance often in conjunction with the waggle dance as a way to entice resting bees to begin foraging, often following prolonged successful foraging or a period of nectar dearth. A honey bee transmitting this signal will literally shake a number of different bees in the hive (approximately 1 to 20 bees per minute) by vibrating her whole body in a dorso‐ventral direction briefly for one to two seconds while holding the other bee tightly in her grasp (Seeley 1995). In contrast to the waggle dance enacted principally on the vertical hive comb near the colony entrance, the shaking signal is performed throughout the hive in an effort to persuade non‐foraging bees involved in other hive activities to switch tasks and begin foraging.
Although the dancing behaviors of honey bees are most familiar, several other physical styles of communication are also used by this social insect to help convey messages both inside and outside of the colony (Winston 1987; Seeley 2010).
Chemical Communication
Complex social living necessitates a rich language, and the significant chemical language of social insects like the honey bee has been compared to the visual and auditory talents of the higher vertebrates (Bell and Carde’ 1984; Slessor et al. 2005). Thomas Seeley (1995) reached the ensuing insight during his long summers spent working on the remarkable social physiology of the honey bee colony: “… the system of control devices found in a honey bee colony is extremely sophisticated and endows a colony with exquisite powers of adaptive response, both to internal changes and to external contingencies.” Together with their notable dancing performances, chemical messages are fundamentally responsible for such extraordinary ability of the honey bee superorganism to adapt to changing conditions (Bortolotti and Costa 2014). However, it is the sociochemicals of the queen, adult worker bees, and brood that largely determine the complex social organization of the colony (Slessor et al. 2005; Jarriault and Mercer 2012).
Pheromones are chemical signals produced by a honey bee and released outside the body to effect a response (Free 1987; Slessor et al. 2005; Bortolotti and Costa 2014). These substances are used among colony members of all castes (queen, workers, drone, and brood) to coordinate hive activities. Such signals may be transferred via antennae contact, olfaction, food transfer, grooming, as well as trail marking or marking resources among others, and are involved in many functions including brood development, foraging, mating, defense, orientation, colony recognition, reproduction, swarming, and division of labor (Figure 4.3). Honey bees use two broad types of pheromones to communicate – primer and releaser pheromones (Free 1987; Slessor et al. 2005). A primer pheromone elicits a complex reaction in the receiver creating both behavioral and developmental changes. Such pheromones are important in the organization and cohesion of eusocial living and include the inhibition of reproduction; examples in the honey bee colony include the Queen Mandibular and Brood pheromones. Primer pheromones are well developed in social insects and act to maintain colony homeostasis. A releaser pheromone has a weaker effect and influences behavior only. Most worker bees utilize releaser pheromones for various hive functions including alarm and aggression, sex attraction, trail marking and recognition (Free 1987; Slessor et al. 2005). Importantly, pheromone communication within a honey bee colony is shaped by the complexity, synergy, context and dose of each signal and conveyed via both temporal and spatial distribution throughout the hive (Slessor et al. 2005).