The defence of the honeybee community

RESP-335

The scent perception of the honeybee

RESP-340

Life-Long Radar Tracking of Bumblebees

This work was supported by European Research Council Advanced Grant no. 339347

Conditioning Individual Mosquitoes to an Odor: Sex, Source, and Time

Olfactory conditioning of mosquitoes may have important implications for vector-pathogen-host dynamics. If mosquitoes learn about specific host attributes associated with pathogen infection, it may help to explain the heterogeneity of biting and disease patterns observed in the field. Sugar-feeding is a requirement for survival in both male and female mosquitoes. It provides a starting point for learning research in mosquitoes that avoids the confounding factors associated with the observer being a potential blood-host and has the capability to address certain areas of close-range mosquito learning behavior that have not previously been described. This study was designed to investigate the ability of the southern house mosquito, Culex quinquefasciatus Say to associate odor with a sugar-meal with emphasis on important experimental considerations of mosquito age (1.2 d old and 3–5 d old), sex (male and female), source (laboratory and wild), and the time between conditioning and testing (<5 min, 1 hr, 2.5 hr, 5 hr, 10 hr, and 24 hr). Mosquitoes were individually conditioned to an odor across these different experimental conditions. Details of the conditioning protocol are presented as well as the use of binary logistic regression to analyze the complex dataset generated from this experimental design. The results suggest that each of the experimental factors may be important in different ways. Both the source of the mosquitoes and sex of the mosquitoes had significant effects on conditioned responses. The largest effect on conditioning was observed in the lack of positive response following conditioning for females aged 3–5 d derived from a long established colony. Overall, this study provides a method for conditioning experiments involving individual mosquitoes at close range and provides for future discussion of the relevance and broader questions that can be asked of olfactory conditioning in mosquitoes

Division of labor in honeybees: form, function, and proximate mechanisms

Honeybees exhibit two patterns of organization of work. In the spring and summer, division of labor is used to maximize growth rate and resource accumulation, while during the winter, worker survivorship through the poor season is paramount, and bees become generalists. This work proposes new organismal and proximate level conceptual models for these phenomena. The first half of the paper presents a push–pull model for temporal polyethism. Members of the nursing caste are proposed to be pushed from their caste by the development of workers behind them in the temporal caste sequence, while middle-aged bees are pulled from their caste via interactions with the caste ahead of them. The model is, hence, an amalgamation of previous models, in particular, the social inhibition and foraging for work models. The second half of the paper presents a model for the proximate basis of temporal polyethism. Temporal castes exhibit specialized physiology and switch caste when it is adaptive at the colony level. The model proposes that caste-specific physiology is dependent on mutually reinforcing positive feedback mechanisms that lock a bee into a particular behavioral phase. Releasing mechanisms that relate colony level information are then hypothesized to disrupt particular components of the priming mechanisms to trigger endocrinological cascades that lead to the next temporal caste. Priming and releasing mechanisms for the nursing caste are mapped out that are consistent with current experimental results. Less information-rich, but plausible, mechanisms for the middle-aged and foraging castes are also presented

Division of labour in the honeybee community

Newly emerged bees in a colony were individually marked, and their foraging activities were studied by subsequent observations at the hive entrance. A few individuals gathered pollen throughout their foraging lives; a considerable number gathered none at all. Most of the bees gathered pollen at some time, but there was great diversity in the part of the foraging life at which this occurred. There was considerable variation in the age at which different bees, emerging on the same day and living in the same colony, commenced foraging; this age ranged from 9 to 35 days. This variation was produced not only by altering the duration of the various hive duties, but also by omitting some of these duties. Such variation indicates that the division of labour is not determined by the age of the available workers. It is controlled, instead, by the requirements of the colony. The ages of the bees in the colony play a subsidiary role, in that the duties of any individual are the resultant of the requirements of the colony and age of that individual. The requirements of the colony are determined by its food supply, and they are appreciated by the individual as a consequence of widespread food transmission. Food transmission is therefore the most primitive and the most important method of communication in the honeybee colony. The duration of foraging life was significantly shorter in those bees which commenced foraging at a later age. This result indicates that senility played a part in determining the longevity of these bees

The foraging method of individual honey-bees

RESP-282

The inability of honeybees to communicate colours

RESP-315