Factors determining the release of Nasonov pheromone by honeybees at the hive entrance

ABSTRACT. Worker bees recently denied access to their colony expose their Nasonov glands, thereby releasing pheromone, at the entrance to their hive. Odours of the following induced this response: empty comb, purified beeswax, honey, pollen, propolis, a live queen, the (E)-9-hydroxy-2-decenoic acid component of a queen's mandibular glands, live drones and workers, inert material on which workers had walked inside the hive, and synthetic Nasonov pheromone. The total odour of a foreign colony also induced worker bees to expose their Nasonov glands but was less effective than the odour of their own colony. Odours of the following were not effective: the (E)-9-oxo-2-decenoic acid component of a queen's mandibular glands, recently killed drones and workers, worker brood (eggs, larvae, pupae).     

The behaviour of queen honeybees and their attendants

Abstract. The behaviour of queen and worker honeybees (Apis mellifera L.) was observed using small colonies in observation hives. Workers paid more attention to queens which had been mated for 2 months or more than to those which were newly mated; virgin queens received least attention. Queens received most attention when they were stationary and least when they were walking over the comb; virgin queens were most active. Queen cells had as many attendants as virgin queens and queen larvae were inspected almost continuously. The queen pheromone component 9–oxo-trans-2–decenoic acid stimulated 'court' behaviour when presented on small polyethylene blocks, but workers responded aggressively to complete extracts of queens' heads. Both the heads and abdomens of mated queens received much attention from court workers but the abdomens were palpated by more workers for longer and were licked much more. The queens' thoraces were least attended. Abdominal tergites posterior to tergite glands were licked for longer than those anterior to the glands. Only worker bees very near to the queen reacted to her and joined her 'court'.
No evidence was found of a diel periodicity in the behaviour of a queen or her 'court'. During the winter the queen's court was smaller than in summer and she walked less and laid fewer eggs. When colonies were fed with sucrose syrup in winter, their queens laid more eggs and workers reared more brood but there was no change in the attention received by the queens.
The implications of these findings for the secretion and distribution of queen pheromones are discussed.     

Effects of Low Doses of Fluoride on Serum Proteins and a Serum Enzyme in Man

FLUORIDE ions have long been known to exert an inhibitory effect on the activity of certain enzymes-Frajola¹ lists ten human enzymes which are definitely inhibited in vitro and suggests that there may be more. In an experiment in one subject receiving 36 mg of sodium fluoride daily for 18 days Frajola was able to show that the activities of the serum enzymes lactic dehydrogenase, acid phosphatase and glutamic transaminase were reduced, but he does not say whether the general health of the subject was affected. Opponents of fluoridation as a public health measure argue that the action as an enzyme inhibitor will affect general health and they quote instances of subjectively assessed ill-health and allergylike reactions following fluoridation of public water supplies, but careful medical observations in fluoridated areas have shown no increase of systemic disease and no significant variation in mortality rates. It has been stated² that there is no evidence that fluoride ingested at 1 p.p.m. in drinking water has any effect on human enzyme activity, but there are no specific experimental data on this question.     

A major difference between the divergence patterns within the lines-1 families in mice and voles

L1 retroposons are represented in mice by subfamilies of interspersed sequences of varied abundance. Previous analyses have indicated that subfamilies are generated by duplicative transposition of a small number of members of the L1 family, the progeny of which then become a major component of the murine L1 population, and are not due to any active processes generating homology within preexisting groups of elements in a particular species. In mice, more than a third of the L1 elements belong to a clade that became active approximately 5 Mya and whose elements are > or = 95% identical. We have collected sequence information from 13 L1 elements isolated from two species of voles (Rodentia: Microtinae: Microtus and Arvicola) and have found that divergence within the vole L1 population is quite different from that in mice, in that there is no abundant subfamily of homologous elements. Individual L1 elements from voles are very divergent from one another and belong to a clade that began a period of elevated duplicative transposition approximately 13 Mya. Sequence analyses of portions of these divergent L1 elements (approximately 250 bp each) gave no evidence for concerted evolution having acted on the vole L1 elements since the split of the two vole lineages approximately 3.5 Mya; that is, the observed interspecific divergence (6.7%-24.7%) is not larger than the intraspecific divergence (7.9%-27.2%), and phylogenetic analyses showed no clustering into Arvicola and Microtus clades.      

The Movement of Calcium in Germinating Pea Seeds

Pea seeds contain less calcium than phosphorus, potassium ormagnesium; more than half of this calcium is located in thetesta. Peas at either end of a pod have more calcium than thosein the middle. When pea seeds are allowed to germinate in water,less than 30 per cent of the cotyledonary calcium moved to thegrowing axis during the first 15 days of germination, whereas70–90 per cent of magnesium, potassium and phosphate wasexported. Various attempts to increase the amount of calciumexported were not successful. When radioactive calcium was appliedto the cotyledons, essentially no movement to the axis was observedunder conditions where extensive movement of radioactive phosphateoccurred.