Summary

Experimental hives obtained from cordovan queens that were instrumentally inseminated with semen from one cordovan and one Italian drone were set up and allowed to swarm. Cordovan provides a resessive genetic marker system (cuticle color) so that the workers from the cordovan and Italian male lines are distinguishable. Our results show that these patrilineal worker groups segregate non-randomly during colony fission and this segregation cannot be explained by observed age structure. Evidence of innate kin recognition in bees has been previously established. We argue that kin recognition could be responsible for the observed non-random grouping of kin during swarming.

Summary

The genetic load associated with the method of sex determination in honey bees has been a great deterrent to selective breeding programmes, primarily because of a lack of understanding of the population genetics of the system. In this paper we examine the distribution of diploid brood viabilities in closed, random mating populations, as a function both of the system of sex determination and of multiple mating in queens. Analytically we show that for a given number of sex alleles, an increase in the numbers of matings of queens, reduces the variance in brood viability, but does not affect the mean. The results of a computer simulation demonstrate that the equilibrium number of sex alleles is approached very slowly from above, so that small populations that start with large numbers of sex alleles will maintain high brood viability for a long time. The practical significance of this is discussed.

The compound eye of worker honeybees with an inborn disturbance of intermediate metabolism of tryptophan — the snow (s) and laranja (la) mutations — has increased sensitivity to light, at least 100 times higher than normal in snow and at least 10 times higher in laranja. The maxima of the spectral sensitivity curves for the whole eye in snow are shifted into the 530 nm region and in laranja to 550 nm (comparedwith 545 nm for the wild type). The electroretinograms of s andla homozygotes are unusual in form on account of the presence of a fast additional component of the receptor potential that is absent in wild-type individuals. This may be the result of immaturity of the pigment granules in the mutants, due to the inherited absence of ommochromes. Pigment granules probably play an important role not only in the formation of the light-protective screen of the ommatidium, but also in biochemical processes considered to be responsible for the electrical passivity of the photoreceptor membrane. The possibility likewise cannot be ruled out that inherited changes in the photoreceptor membranes are connected with an imbalance between derivatives of tryptophan metabolism which participate in the generation of the cell receptor potential.

The plasma membrane-cell surface complex is of crucial significance for the social behavior of cells within cell populations (Nicolson 1977; Poste 1977; Nicolson et al. 1977). Alterations in cell surface organization may account for cellular misbehavior. This asocial behavior is termed malignancy when it meets two criteria: loss of growth control (resulting in excessive proliferation) and loss of positional control (resulting in invasion and metastasis).