Bees are used to pollinate plants in isolation cages. Usually the bees have previously flown about freely in the open air and may have gathered pollen from the same plant species.
Now the question arises whether the bees can contaminate with this pollen plants with whick they are enclosed in an isolation cage. In this connection a number of experiments were undertaken to find out how long bees are loaded with germinable pollen. It appeared that the risk of contamination was practicalIy eliminated by keeping the bees in a house or empty isolation cage for 12 hours.
Tests made on larvae in normal bee colonies with pure cultures of Streptococcus pluton (White), Streptococcus faecalis Andrews and Horder, and Bacillus alvei Cheshire and Cheyne, three bacterial species commonly associated with European foulbrood (EFB), showed that S. pluton was the natural prirnary etiological agent. These results, together with other recent work, indicate that S. pluton is the cause of EFB throughout the world. Of the other associated bacterial species, Bacterium eurydice White, which is the most commnon, and S. faecalis probably have supplementary pathogenic effects. Bacillus alvei and other less common bacilli are saprophytes of the dead larvae.
An outbreak of a septicaemic condition of bees occurred in East Gippsland, Victoria, during the autumn, winter, and spring of 1958. The condition appears to conform generally with cases of septicaemia recorded in Canada, United States, and France. A causative organism has been isolated from septicaemic bees in Victoria which appears to fall into the type of the Pseudomonas species of Landerkin and Katznelson (1959). This organism has been proved pathogenic to bees when inoculated by dipping or injection.
Honey bees (Apis mellifera Linnaeus) from Austria and Switzerland, suffering from Waldtrachtkrankheit, and from Italy and Norway suffering from Mal Noir contained as much chronic bee paralysis virus as bees suffering from “paralysis” in Britain and Malta. These diseases appear to be etiologically the same, therefore, and the variable and unreliable signs sometimes exhibited are perhaps caused by factors secondary to infection by the virus. Apparently healthy bees from Canada and Italy were infected with the virus of acute paralysis, as they are in Britain.
A community of honeybees is an integrated group, the members of which can distinguish other members from intruders. Individual bees can pass on detailed information about the nature and location of food sources ; they will produce a new queen only when the old one is no longer satisfactory. These different functions are discussed and illustrated in this article ; the discussion of queen rearing is made particularly appropriate by the recent discovery of the chemical nature of queen substance. The photographs are by Treat Davidson.
The rate of increase of population in societies of social insects obviously depends upon the numbers of adults which can be produced per head of the adult population. Ideally, the numbers of eggs laid should be just appropriate to this situation, so that the prevailing food supply may be efficiently transformed.
There is a natural tendency for untrained scouting bees to associate certain perfumes with food (e.g. those of the flowers of Crataegus oxyacantha and Trifolium repens) whereas the perfume of some other flowers (e.g. Spirea arguta) are unattractive to the honeybee. If the perfume of a new crop of flowers is sufficiently strong it will sometimes attract scouting bees when they are still unable to see the flowers. It is often necessary for a bee to approach within an inch or so of a flower before she can discern any perfume it may possess. When a bee approaches an object closely enough any attractive perfume it may possess tends to act as a stimulus to further exploration which involves settling upon the object and possibly seeking food in any small crevice in or around it. Thus the perfume of the individual flower plays an important part in stimulating a nectar-seeking bee to enter it, whether she has learned to associate its perfume with food or not. Normal visitation of a flower which has previously been worked is suspended when the bee's olfactory sense is disturbed. This can be caused either by mutilation or by the presence of a strong foreign perfume. In general the results obtained from experiments with untrained bees support the conclusions reached by von Frisch (1919) in his work with trained bees...
It is a relaxation to turn from the pressing problems of our own community life to study for a while the social life of the honey bee, which is very interesting and quite different from our own. Only a small proportion of the two million different kinds of insects that exist today live in communities, and of these only a few share the honey bee's habit of living in a large and well-organized society.
We know more about the mode of life and the behavior of the honey bee than that of any other social insect, because the economic value of its honey and its wax made it worth while for man to domesticate this insect, with the result that its activities have been kept under close observation for many centuries.
As in aIl other social insects, the family forms the social unit, and there has been no integration above that level; never does one come across a number of families associating together to form a cornmunity in the way that happens in the case of man. Nevertheless a honey-bee colony can reach a considerable size, and it may come to contain as many as 70,000 worker bees, aIl of them the progeny of one fertile female, their queen. The queen lays aIl the eggs, and the workers carry out aIl the other work of the colony. The efficient functioning of this large family is clearly impossible unless its members are able to communicate with each other effectively...
1. The phenomenon of "shaking" in honeybee colonies is described, and is here considered in relation to the queen of the colony.
2. The queen was rarely shaken in the spring but once swarm preparations had commenced the frequency of shaking rose rapidly, reaching a peak at about the time the swarm left. A newlymated young queen was shaken to some extent just after she first commenced laying, but within a few days the frequency had fallen markedly, and finally no shaking was observed. Since the queens were shaken only at times when they were likely to fly out of the hive it is concluded that there is a connection between the two events. Hammann (1957) gives results on unmated queens which also support this assumption, for these queens were shaken with increasing frequency before each mating flight.
3. The ages of the queen's shakers ranged from 3 to 61 days but the greatest numbers occurred in approximately the fourth week of adult life.
Les contacts trophallactiques qui apparaissent comme un des fondements de la vie sociale chez les insectes ont toujours préoccupé les biologistes.
Mais on ne sait toujours pas comment se déroulent les échanges de nourriture et quels sont les rôles exacts joués par les pièces buccales et les différents éléments sensoriels mis en jeu. Nous avons entrepris d'éclaircir ces aspects constants et fondamentaux de la vie sociale chez les guêpes du genre Vespa. Pour cela, nous avons filmé systématiquement, en vitesse accélérée, de nombreuses séquences trophallactiques en fonction de l'âge, de la dominance et de la caste des partenaires. L'analyse des films a été faite image par image.
1. 1. Sterold have been extracted from 3 insects, Calotermes flavicollis, Gryllus domesticus and Apis mellifica, and their characteristics determined by means of mass spectrometer.
2. 2. Cholesterol is the principal sterol of Calotermes and Gryllus.
3. 3. The principal sterol in Apis is 24-methylene cholesterol.
4. 4. The presence of minor sterols is reported.
Matériel et méthodes de travail.
Localisation de la phérormone.
Mode d'action de la phérormone.
Nature chimique de la phérormone.
Les ouvrières et l'apparition de la phérormone : le cycle de la phérormone.
Les interactions sociales et la phérormone.
Recherches parallèles effectuées chez les termites, les fourmis et les Halictes.
Conclusions générales. /// CONTENTS: History.
Materials and methods.
Pherormone mode of action.
Chemistry of the pherormone.
Workers and pherormone: the pherormone cycle.
Social interactions and pherormone.
Similar researches on termites, ants and Halictes.
General conclusions.; Thèse de doctorat ès Sciences naturelles