Stingless bees in the genus Tetragonula are social insects with a fully sterile worker caste, and are therefore well‐placed to provide insights into the genomic changes associated with ‘superorganismal’ life histories. Here we assemble the genome of Tetragonula carbonaria and characterise the population structure and divergence of both T. carbonaria and its cryptic congener T. hockingsi in eastern Australia, revealing three di...

The presence of DNA methylation marks within genic intervals, also called gene body methylation, is an evolutionarily‐conserved epigenetic hallmark of animal and plant methylomes. In social insects, gene body methylation is thought to contribute to behavioural plasticity, for example between foragers and nurse workers, by modulating gene expression. However, recent studies have suggested that the majority of DNA methylation is...

The Kinship Theory of Genomic Imprinting (KTGI) posits that, in species where females mate with multiple males, there is selection for a male to enhance the reproductive success of his offspring at the expense of other males and his mating partner. Reciprocal crosses between honey bee subspecies show parent‐of‐origin effects for reproductive traits, suggesting that males modify the expression of genes related to female functio...

The hallmark of eusociality is the division of labour between reproductive (queen) and nonreproductive (worker) females. Yet in many eusocial insects, workers retain the ability to produce haploid male offspring from unfertilized eggs. The reproductive potential of workers has well‐documented consequences for the structure and function of insect colonies, but its implications at the population level are less often considered....

Functional worker sterility is the defining feature of insect societies. Yet, workers are sometimes found reproducing in their own or foreign colonies. The proximate mechanisms underlying these alternative reproductive phenotypes are keys to understanding how reproductive altruism and selfishness are balanced in eusocial insects. In this study, we show that in honeybee ( Apis mellifera ) colonies, the social environment of a w...

Reproductive isolation between closely related species is often incomplete. The Western honeybee, A pis mellifera , and the E astern hive bee, A pis cerana , have been allopatric for millions of years, but are nonetheless similar in morphology and behaviour. During the last century, the two species were brought into contact anthropogenically, providing potential opportunities for interspecific matings. Hybrids between A. melli...

Kin selection theory predicts that honeybee ( A pis mellifera ) workers should largely refrain from producing their own offspring, as the workers collectively have higher inclusive fitness if they rear the sons of their mother, the queen. Studies that have quantified levels of ovary activation and reproduction among workers have largely supported this prediction. We sampled pre‐emergent male pupae and adult workers from seven...

Humans have been keeping honey bees, Apis mellifera , in artificial hives for over 7000 years. Long enough, one might imagine, for some genetic changes to have occurred in domestic bees that would distinguish them from their wild ancestors. Indeed, some have argued that the recent mysterious and widespread losses of commercial bee colonies, are due in part to inbreeding. In this issue of Molecular Ecology , Harpur et al. (2012...

During reproductive swarming, some workers of the Cape honey bee, Apis mellifera capensis , lay eggs in queen cells, many of which are reared to maturity. However, it is unknown if workers are able to lay in queen cells immediately after queen loss during an episode of emergency queen rearing. In this study we experimentally de‐queened colonies and determined the maternity of larvae and pupae that were reared as queens. This a...

Honeybee hygienic behaviour provides colonies with protection from many pathogens and is an important model system of the genetics of a complex behaviour. It is a textbook example of complex behaviour under simple genetic control: hygienic behaviour consists of two components – uncapping a diseased brood cell, followed by removal of the contents – each of which are thought to be modulated independently by a few loci of medium...

Reproduction by workers is rare in honey bee colonies that have an active queen. By not producing their own offspring and preventing other workers from producing theirs, workers are thought to increase their inclusive fitness due to their higher average relatedness towards queen‐produced male offspring compared with worker‐produced male offspring. But there is one exception. Workers of the Cape honey bee, Apis mellifera capens...