Vibrational signals in the tremble dance of the honeybee,Apis mellifera

Summary The tremble dance is a behavior sometimes performed by honeybee foragers returning to the hive. The biological significance of this behavior was unclear until Seeley (1992) demonstrated that tremble dances occur mainly when a colony's nectar influx is so high that the foragers must undertake lenghty searches in order to find food storers to unload their nectar. He suggested that tremble dancing has the effect of stimulating additional bees to function as food-storers, thereby raising the colony's capacity for processing nectar. Here I describe vibrational signals emitted by the tremble dancers. Simulation experiments with artificial tremble dance sounds revealed that these sounds inhibited dancing and reduced recruitment to feeding sites. The results suggest that the tremble dance is a negative feedback system counterbalancing the positive feedback of recruitment by waggle dances. Thus, the tremble dance seems to affect not only the colony's nectar processing rate, but also its nectar intake rate.     

The stop signal of honey bees: reconsidering its message

Summary The stop signal of honey bees has long been regarded as a vibrational begging signal produced by dance followers to elicit food from waggle dancers (Esch 1964). On the basis of playback experiments and behavioral analysis, this study presents the following evidence for a different signal function. Stop signals (1) can be produced by tremble dancers, dance followers, and waggle dancers; (2) rarely elicit trophallaxis; and (3) evidently cause waggle dancers to leave the dance floor. Subsequent work by Kirchner (submitted) using vibrational playback experiments confirms the latter observation. When the colony's food storers are temporarily overwhelmed by a large nectar influx, returning foragers will search for prolonged periods before unloading food and consequently begin to tremble dance (Seeley 1992). In this study, tremble dancers were the major producer of stop signals on the dance floor. The stop signal may thus retard recruitment until balance is restored.     

The occurrence and context of tremble dancing in free-foraging honey bees (<Emphasis Type="Italic">Apis mellifera</Emphasis>)

Nectar foraging in honey bees is regulated by several communication signals that are performed mainly by foragers. One of these signals is the tremble dance, which is consistently performed by foragers from a rich food source which, upon return to the hive, experience a long delay before unloading their nectar to a nectar receiver. Although tremble dancing has been studied extensively using artificial nectar sources, its occurrence and context in a more natural setting remain unknown. Therefore, this study tests the sufficiency of the current explanations for tremble dancing by free-foraging honey bees. The main finding is that only about half of the observations of tremble dancing, referred to as delay-type tremble dancing, are a result of difficulty in finding a nectar receiver. In the remaining observations, tremble dancing was initiated immediately upon entering the hive, referred to as non-delay-type tremble dancing. Non-delay tremble dancing was associated with first foraging successes, both in a forager's career and in a single day. More than 75% of tremble dancing was associated with good foraging conditions, as indicated by the dancer continuing to forage after dancing. However, at least some of the other cases were associated with deteriorated foraging conditions, such as the end of the day, after which foraging was discontinued. No common context could be identified that explains all cases of tremble dancing or the subset of non-delay-type tremble dancing. This study shows that the current explanations for the cause of the tremble dance are insufficient to explain all tremble dancing in honey bees that forage at natural food sources.     

Worker allocation in insect societies: coordination of nectar foragers and nectar receivers in honey bee (Apis mellifera) colonies

Nectar collection in the honey-bee is partitioned. Foragers collect nectar and take it to the nest, where they transfer it to receiver bees who then store it in cells. Because nectar is a fluctuating and unpredictable resource, changes in worker allocation are required to balance the work capacities of foragers and receivers so that the resource is exploited efficiently. Honey bee colonies use a complex system of signals and other feedback mechanisms to coordinate the relative and total work capacities of the two groups of workers involved. We present a functional evaluation of each of the component mechanisms used by honey bees – waggle dance, tremble dance, stop signal, shaking signal and abandonment – and analyse how their interplay leads to group-level regulation. We contrast the actual regulatory system of the honey bee with theory. The tremble dance conforms to predicted best use of information, where the group in excess applies negative feedback to itself and positive feedback to the group in shortage, but this is not true of the waggle dance. Reasons for this and other discrepancies are discussed. We also suggest reasons why honey bees use a combination of recruitment plus abandonment and not switching between subtasks, which is another mechanism for balancing the work capacities of foragers and receivers. We propose that the waggle and tremble dances are the primary regulation mechanisms, and that the stop and shaking signals are secondary mechanisms, which fine-tune the system. Fine-tuning is needed because of the inherent unreliability of the cues, queueing delays, which foragers use to make recruitment decisions. Received: 15 December 1998 / Received in revised form: 6 March 1999 / Accepted: 12 March 1999     

Promiscuous honeybee queens generate colonies with a critical minority of waggle-dancing foragers

Honeybees present a paradox that is unusual among the social Hymenoptera: extremely promiscuous queens generate colonies of nonreproducing workers who cooperate to rear reproductives with whom they share limited kinship. Extreme polyandry, which lowers relatedness but creates within-colony genetic diversity, produces substantial fitness benefits for honeybee queens and their colonies because of increased disease resistance and workforce productivity. However, the way that these increases are generated by individuals in genetically diverse colonies remains a mystery. We assayed the foraging and dancing performances of workers in multiple-patriline and single-patriline colonies to discover how within-colony genetic diversity, conferred to colonies by polyandrous queens, gives rise to a more productive foraging effort. We also determined whether the initiation by foragers of waggle-dance signaling in response to an increasing sucrose stimulus (their dance response thresholds) was linked to patriline membership. Per capita, foragers in multiple-patriline colonies visited a food source more often and advertised it with more waggle-dance signals than foragers from single-patriline colonies, although there was variability among multiple-patriline colonies in the strength of this difference. High-participation patrilines emerged within multiple-patriline colonies, but their more numerous foragers and dancers were neither more active per capita nor lower-threshold dancers than their counterparts from low-participation patrilines. Our results demonstrate that extreme polyandry does not enhance recruitment effort through the introduction of low-dance-threshold, high-activity workers into a colony’s population. Rather, genetic diversity is critical for injecting into a colony’s workforce social facilitators who are more likely to become engaged in foraging-related activities, so boosting the production of dance signals and a colony’s responsiveness to profitable food sources.     

The tremble dance of the honey bee: message and meanings

Summary The nectar foragers of a honey bee colony, upon return to the hive, sometimes perform a mysterious behavior called the tremble dance. In performing this dance, a forager shakes her body back and forth, at the same time rotating her body axis by about 50° every second or so, all the while walking slowly across the comb. During the course of a dance, which on average lasts 30 min, the bee travels about the broodnest portion of the hive. It is shown experimentally that a forager will reliably perform this dance if she visits a highly profitable nectar source but upon return to the hive experiences great difficulty finding a food-storer bee to take her nectar. This suggests that the message of the tremble dance is I have visited a rich nectar source worthy of greater exploitation, but already we have more nectar coming into the hive than we can handle. It is also shown experimentally that the performance of tremble dances is followed quickly by a rise in a colony's nectar processing capacity and (see Nieh, in press and Kirchner, submitted) by a drop in a colony's recruitment of additional bees to nectar sources. These findings suggest that the tremble dance has multiple meanings. For bees working inside the hive, its meaning is apparently I should switch to the task of processing nectar, while for bees working outside the hive (gathering nectar), its meaning is apparently I should refrain from recruiting additional foragers to my nectar source. Hence it appears that the tremble dance functions as a mechanism for keeping a colony's nectar processing rate matched with its nectar intake rate at times of greatly increased nectar influx. Evidently the tremble dance restores this match in part by stimulating a rise in the processing rate, and in part by inhibiting any further rise in the intake rate. Correspondence to: T. Seeley     

Floral scents affect the distribution of hive bees around dancers

Floral scents are important information cues used to organize foraging-related tasks in honeybees. The waggle dance, apart from encoding spatial information about food sources, might facilitate the transfer of olfactory information by increasing the dissipation of volatiles brought back by successful foragers. By assuming that food scents are more intensive on specific body parts of returning foragers, i.e., the posterior legs of pollen foragers and mouthparts of nectar foragers, we quantified the interactions between hive mates and foragers during dances advertising different types of food sources. For natural sources, a higher proportion of hive mates contacted the hind legs of pollen dancers (where the pollen loads were located) with their heads compared to non-pollen dancers. On the other hand, the proportion of head-to-head contacts was higher for non-pollen foragers during the waggle runs. When the food scent was manipulated, dancers collecting scented sugar solution had a higher proportion of head-to-head contacts and a lower proportion around their hind legs compared to dancers collecting unscented solution. The presence of food odors did not affect in-hive behaviors of dancers, but it increased the number of trophallaxes in-between waggle runs (i.e., during circle phases). These results suggest that the honeybee dance facilitates the olfactory information transfer between incoming foragers and hive mates, and we propose that excitatory displays in other social insect species serve the same purpose. While recent empirical and theoretical findings suggested that the colony level foraging benefits of the spatial information encoded in the waggle dance vary seasonally and with habitats, the role of the dance as a compound signal not only indicating the presence of a profitable resource but also amplifying the information transfer regarding floral odors may be important under any ecological circumstances.     

Colony-level selection effects on individual and colony foraging task performance in honeybees, Apis mellifera L.

In honeybees, as in other highly eusocial species, tasks are performed by individual workers, but selection for worker task phenotypes occurs at the colony level. We investigated the effect of colony-level selection for pollen storage levels on the foraging behavior of individual honeybee foragers to determine (1) the relationship between genotype and phenotypic expression of foraging traits at the individual level and (2) how genetically based variation in worker task phenotype is integrated into colony task organization. We placed workers from lines selected at the colony level for high or low pollen stores together with hybrid workers into a common hive environment with controlled access to resources. Workers from the selected lines showed reciprocal variation in pollen and nectar collection. High-pollen-line foragers collected pollen preferentially, and low- pollen-line workers collected nectar, indicating that the two tasks covary genetically. Hybrid workers were not intermediate in phenotype, but instead showed directional dominance for nectar collection. We monitored the responses of workers from the selected strains to changes in internal (colony) and external (resource) stimulus levels for pollen foraging to measure the interaction between genotypic variation in foraging behavior and stimulus environment. Under low-stimulus conditions, the foraging group was over-represented by high-pollen-line workers. However, the evenness in distribution of the focal genetic groups increased as foraging stimuli increased. These data are consistent with a model where task choice is a consequence of genetically based response thresholds, and where genotypic diversity allows colony flexibility by providing a range of stimulus thresholds. Received: 3 May 1999 / Received in revised form: 22 December 1999 / Accepted: 23 January 2000     

The use of waggle dance information by honey bees throughout their foraging careers

We studied the extent to which worker honey bees acquire information from waggle dances throughout their careers as foragers. Small groups of foragers were monitored from time of orientation flights to time of death and all in-hive behaviors relating to foraging were recorded. In the context of a novice forager finding her first food source, 60% of the bees relied, at least in part, on acquiring information from waggle dances (being recruited) rather than searching independently (scouting). In the context of an experienced forager whose foraging has been interrupted, 37% of the time the bees resumed foraging by following waggle dances (being reactivated) rather than examining the food source on their own (inspecting). And in the context of an experienced forager engaged in foraging, 17% of the time the bees initiated a foraging trip by following a waggle dance. Such dance following was observed much more often after an unsuccessful than after a successful foraging trip. Successful foragers often followed dances just briefly, perhaps to confirm that the kind of flowers they had been visiting were still yielding forage. Overall, waggle dance following for food discovery accounted for 12–25% of all interactions with dancers (9% by novice foragers and 3–16% by experienced foragers) whereas dance following for reactivation and confirmation accounted for the other 75–88% (26% for reactivation and 49–62% for confirmation). We conclude that foragers make extensive use of the waggle dance not only to start work at new, unfamiliar food sources but also to resume work at old, familiar food sources.     

The role of the vibration signal in the house-hunting process of honey bee (<Emphasis Type="Italic">Apis mellifera</Emphasis>) swarms

The function of the vibration signal of the honey bee (Apis mellifera) during house hunting was investigated by removing vibrating bees from swarms and examining the effects on waggle dancing for nest sites, liftoff preparations and swarm movement. We compared house hunting among three swarm types: (1) test swarms (from which vibrating bees were removed), (2) manipulated control (MC) swarms (from which randomly selected workers and some waggle dancers were removed), and (3) unmanipulated control (UC) swarms (from which no bees were removed). The removal of vibrating bees had pronounced effects on liftoff preparations and swarm movement. Compared to the MC and UC swarms, the test swarms had significantly greater liftoff-preparation periods, were more likely to abort liftoff attempts, and in some cases were unable to move to the chosen site after the swarm became airborne. However, the three swarm types did not differ in overall levels of waggle dance activity, the time required to achieve consensus for a nest site, the rate at which new waggle dancers were recruited for the chosen site, or the ability to maintain levels of worker piping necessary to prepare for flight. The removal of vibrating bees may therefore have altered liftoff behavior because of a direct effect on vibration signal activity. A primary function of the signal during house hunting may be to generate a level of activity in workers that enhances and coordinates responses to other signals that stimulate departure and movement to a new location.Communicated by R. Page     

The causes of the tremble dance of the honeybee,Apis mellifera

Tremble dances are sometimes performed by returning forager bees instead of waggle dances. Recent studies by Seeley (1992) and Kirchner (1993) have revealed that this behaviour is part of the recruitment communication system of bees. The ultimate cause of tremble dances is, according to Seeley (1992), an imbalance between the nectar intake rate and the nectar processing capacity of the colony. This imbalance is correlated with a long initial search time of returning foragers to find bees to unload them. However, it remained unclear whether a long search time is the direct proximate cause of tremble dancing. Here we report that a variety of experimental conditions can elicit tremble dances. All of them have in common that the total search time that foragers spend searching for unloaders, until they are fully unloaded, is prolonged. This finding supports and extends the hypothesis that a long search time is the proximate cause of tremble dancing. The results also confirm the previous reports of Lindauer (1948) and others about factors eliciting tremble dancing.     

Colony nutritional status modulates worker responses to foraging recruitment pheromone in the bumblebee Bombus terrestris

Foraging activity in social insects should be regulated by colony nutritional status and food availability, such that both the emission of, and response to, recruitment signals depend on current conditions. Using fully automatic radio-frequency identification (RFID) technology to follow the foraging activity of tagged bumblebees (Bombus terrestris) during 16,000 foraging bouts, we tested whether the cue provided by stored food (the number of full honeypots) could modulate the response of workers to the recruitment pheromone signal. Artificial foraging pheromones were applied to colonies with varied levels of food reserves. The response to recruitment pheromones was stronger in colonies with low food, resulting in more workers becoming active and more foraging bouts being performed. In addition to previous reports showing that in colonies with low food successful foragers perform more excited runs during which they release recruitment pheromone and inactive workers are more prone to leave the nest following nectar influx, our results indicate that evolution has shaped a third pathway that modulates bumblebee foraging activity, thus preventing needless energy expenditure and exposure to risk when food stores are already high. This new feedback loop is intriguing since it involves context-dependent response to a signal. It highlights the integration of information from both forager-released pheromones (signal) and nutritional status (cue) that occurs within individual workers before making the decision to start foraging. Our results support the emerging view that responses to pheromones may be less hardwired than commonly acknowledged. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Why do honey-bee (Apis millifera) foragers transfer nectar to several receivers? Information improvement through multiple sampling in a biological system

The task of nectar foraging in honey-bees is partitioned between foragers and receivers. Foragers typically transfer a nectar load in the nest as sub-loads to several receivers rather than as a single transfer. Foragers experience delays in finding receivers and use these delays to balance the number of foragers and receivers. A short delay results in the forager-recruiting waggle dance whereas a long delay results in the receiver-recruiting tremble dance. Several nectar transfers increase the cost of this system by introducing additional delays in finding extra receivers. We tested four hypotheses to explain the occurrence of multiple transfer. We found no evidence that multiple transfer is due to different crop capacities of foragers and receivers or that it results from extensive trophallactic interactions with nest-mates. Receiver bees frequently evaporate nectar in their mouthparts to hasten the production of honey. The suggestion has been made that multiple transfer is driven by receivers who take partial loads from foragers to enhance nectar evaporation. An alternative suggestion is that foragers drive multiple transfer to gain better information on the balance of foragers and receivers. Multiple sampling of the delay in finding a receiver reduces the standard deviation of the delay mean and so provides foragers with better information than is provided by a single delay. The enhanced-evaporation hypothesis predicts that receivers break foragers' first transfer whereas the information improvement hypothesis predicts foragers break their first transfers. Furthermore, only the information improvement hypothesis predicts a high level of multiple receptions. Data on transfer break-off and receiver behaviour strongly support the information improvement hypothesis and reject the enhanced-evaporation hypothesis. We suggest that multiple transfer is an adaptive sampling mechanism, which improves foragers' information on colony work allocation, and that multiple sampling is a common feature of social insect societies.     

The honey bee’s tremble dance stimulates additional bees to function as nectar receivers

If a forager bee returns to her hive laden with high-quality nectar but then experiences difficulty finding a receiver bee to unload her, she will begin to produce a conspicuous communication signal called the tremble dance. The context in which this signal is produced suggests that it serves to stimulate more bees to function as nectar receivers, but so far there is no direct evidence of this effect. We now report an experiment which shows that more bees do begin to function as nectar receivers when foragers produce tremble dances. When we stimulated the production of tremble dances in a colony and counted the number of bees engaged in nectar reception before and after the period of intense tremble dancing, we found a dramatic increase. In two trials, the number of nectar receivers rose from 17% of the colony’s population before tremble dancing to 30–50% of the population after the dancing. We also investigated which bees become the additional nectar receivers, by looking at the age composition of the receiver bees before and after the period of intense tremble dancing. We found that none of the bees recruited to the task of nectar reception were old bees, most were middle-aged bees, and some were even young bees. It remains unclear whether these auxiliary nectar receivers were previously inactive (as a reserve supply of labor) or were previously active on other tasks. Overall, this study demonstrates that a honey bee colony is able to rapidly and strongly alter its allocation of labor to adapt to environmental changes, and it further documents one of the communication mechanisms underlying this ability. Received: 31 May 1996/Accepted after revision: 9 August 1996     

Division of foraging labor in ants can mediate demands for food and safety

Solitary foragers can balance demands for food and safety by varying their relative use of foraging patches and their level of vigilance. Here, we investigate whether colonies of the ant, Formica perpilosa, can balance these demands by dividing labor among workers. We show that foragers collecting nectar in vegetation near their nest are smaller than are those collecting nectar at sites away from the nest. We then use performance tests to show that smaller workers are more likely to succumb to attack from conspecifics but feed on nectar more efficiently than larger workers, suggesting a size-related trade-off between risk susceptibility and harvesting ability. Because foragers that travel away from the nest are probably more likely to encounter ants from neighboring colonies, this trade-off could explain the benefits of dividing foraging labor among workers. In a laboratory experiment, we show that contact with aggressive workers results in an increase in the mean size of recruits to a foraging site: this increase was not the result of more large recruits, but rather because fewer smaller ants traveled to the site. These results suggest that workers particularly susceptible to risk avoid dangerous sites, and suggest that variation in worker size can allow colonies to exploit profitably both hazardous and resource-poor patches.Communicated by L. Sundström     

What makes a honeybee scout?

A honeybee colony needs to divide its workforce so that each of the many tasks it performs has an appropriate number of workers assigned to it. This task allocation system needs to be flexible enough to allow the colony to quickly adapt to an ever-changing environment. In this study, we examined possible mechanisms by which a honeybee colony regulates the division of labor between scouts (foragers that search for new food sources without having been guided to them) and recruits (foragers that were guided via recruitment dances toward food sources). Specifically, we examined the roles that the availability of recruitment dances and worker genotype has in the colony-level regulation of the number of workers engaged in scouting. Our approach was threefold. We first developed a mathematical model to demonstrate that the decision to become a scout or a recruit could be regulated by whether a potential forager can find a recruitment dance within a certain time period. We then tested this model by investigating the effect of dance availability on the regulation of scouts in the field. Lastly, we investigated if the probability of being a scout has a genetic basis. Our field data supported the hypothesis that scouts are those foragers that have failed to locate a recruitment dance as predicted by our model, but we found no effect of genotype on the propensity of foragers to become scouts.     

Heritable variation in learning performance affects foraging preferences in the honey bee (Apis mellifera)

There has now been an abundance of research conducted to explore genetic bases that underlie learning performance in the honey bee (Apis mellifera). This work has progressed to the point where studies now seek to relate genetic traits that underlie learning ability to learning in field-based foraging problems faced by workers. Accordingly, the focus of our research is to explore the correlation between laboratory-based performance using an established learning paradigm and field-based foraging behavior. To evaluate learning ability, selected lines were established by evaluating queens and drones in a proboscis extension reflex (PER) conditioning procedure to measure learning in a laboratory paradigm—latent inhibition (LI). Hybrid queens were then produced from our lines selected for high and low levels of LI and inseminated with semen from many drones chosen at random. The genetically diverse worker progeny were then evaluated for expression of LI and for preference of pollen and/or nectar during foraging. Foragers from several different queens, and which had resulted from fertilization by any of several different drone fathers, were collected as they returned from foraging flights and analyzed for pollen and nectar contents. They were subsequently evaluated for expression of LI. Our research revealed that pollen foragers exhibited stronger learning, both in the presence (excitatory conditioning) and absence (LI) of reinforcement. The heightened overall learning ability demonstrated by pollen foragers suggests that pollen foragers are in general more sensitive to a large number of environmental stimuli. This mechanism could contribute toward explanations of colony-level regulation of foraging patterns among workers.Communicated by R. Page     

Behavioral and life-history components of division of labor in honey bees (Apis mellifera L.)

Variability exists among worker honey bees for components of division of labor. These components are of two types, those that affect foraging behavior and those that affect life-history characteristics of workers. Variable foraging behavior components are: the probability that foraging workers collect (1) pollen only; (2) nectar only; and (3) pollen and nectar on the same trip. Life history components are: (1) the age the workers initiate foraging behavior; (2) the length of the foraging life of a worker; and (3) worker length of life. We show how these components may interact to change the social organization of honey bee colonies and the lifetime foraging productivity of individual workers. Selection acting on foraging behavior components may result in changes in the proportion of workers collecting pollen and nectar. Selection acting on life-history components may affect the size of the foraging population and the distribution of workers between within nest and foraging activities. We suggest that these components define possible sociogenic pathways through which colony-level natural selection can change social organization. These pathways may be analogous to developmental pathways in the morphogenesis of individual organisms because small changes in behavioral or life history components of individual workers may lead to major changes in the organizational structure of colonies. Correspondence to: R.E. Page, Jr.     

The effect of foraging specialization on various learning tasks in the honey bee (<Emphasis Type="Italic">Apis mellifera</Emphasis>)

Honey bee foragers may collect nectar, pollen, water, or propolis, and their foraging specialization has been associated with several behavioral traits. By conditioning of the proboscis extension response (PER), we compared the performance of foragers that collected nectar, pollen, both nectar and pollen, or water in several learning and choice assays. Foragers were first tested in a three-trial olfactory associative learning assay. For further tests, we selected only good learners that responded in two out of three conditioning trials. One group was tested in an additional olfactory associative learning assay involving different reward volumes and concentrations. Another group was tested for risk sensitivity in a two-alternative forced-choice PER procedure and then in a latent inhibition (LI) assay. Levels of acquisition in olfactory associative learning were highest in pollen and water foragers, and better acquisition was associated with collection of heavier pollen loads and smaller and lighter nectar loads of lower sugar concentration. Among the good learners, pollen foragers still showed better acquisition than nectar foragers when rewarded with several volumes and concentrations of sucrose solution. Pollen and nectar foragers were equally risk averse, preferring a constant reward to a variable one, and choice was not affected by pollen load weight. Contrary to a previous study, pollen and nectar foragers were similarly affected by LI. We discuss possible explanations for the discrepancy between the two studies. Overall, our results suggest that differences between foraging groups in sensitivity to various stimuli may not correspond to differences in choice behavior.     

Honeybee foragers adjust crop contents before leaving the hive

Upon leaving the hive, foragers carry a small amount of honey, which they subsequently consume to generate energy for flight. We investigated the relationship between waggle-phase duration and crop volume in foragers (both dancers and dance followers) leaving the hive. Our findings indicate that these variables were positively correlated in the two types of bee, suggesting that they were able to adjust the amount of food that they carry depending on the distance to a food source. We also found that dance followers left the hive with a larger amount of honey than dancers. We suggest two possible explanations: (1) dance followers have less information about the location of the food source than dancers, who have a better knowledge of the surrounding area; or (2) honeybees lack a precise calibration method for estimating energy needs from waggle-run duration. The effect of foraging experience was confirmed: bees decreased their honey load at departure with repeated trips to a sugar-syrup feeder. Honeybees showed a different pattern of change when the feeder provided soybean flour as a pollen substitute, possibly because honeybees use honey not only as an energy source but also as “glue” to form “balls” of pollen on their hind legs. Based on our observations that followers of sugar-syrup foragers carry a different amount of honey in their crop than followers of soybean-followers, we suggest that waggle dancers also convey information concerning food type.