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The subspecies of honeybee indigenous to the Cape region of South Africa, Apis mellifera capensis, is unique because a high proportion of unmated workers can lay eggs that develop into females via thelytokous parthenogenesis involving central fusion of meiotic products. This ability allows pseudoclonal lineages of workers to establish, which are presently widespread as reproductive parasites within the honeybee populations of South Africa. Successful long-term propagation of a parthenogen requires the maintenance of heterozygosity at the sex locus, which in honeybees must be heterozygous for the expression of female traits. Thus, in successful lineages of parasitic workers, recombination events are reduced by an order of magnitude relative to meiosis in queens of other honeybee subspecies. Here we show that in unmated A. m. capensis queens treated to induce oviposition, no such reduction in recombination occurs, indicating that thelytoky and reduced recombination are not controlled by the same gene. Our virgin queens were able to lay both arrhenotokous male-producing haploid eggs and thelytokous female-producing diploid eggs at the same time, with evidence that they have some voluntary control over which kind of egg was laid. If so, they are able to influence the kind of second-division meiosis that occurs in their eggs post partum.

Multiple mating of females is widespread, and females often obtain direct and/or indirect benefits by mating with multiple males. However, female control of multiple paternity broods is usually only possible in internally fertilising animals with complex reproductive systems including cryptic female choice. Here we present direct evidence that a cooperative polyandrous cichlid fish with external fertilisation, Julidochromis transcriptus, uses environmental factors to manipulate male access to, and therefore paternity of, their egg clutches. Polyandrous females receive more paternal investment from both of large alpha males and small beta males than monogamous females. We used a 'step nest' design, in which large alpha males and small beta males were restricted to the wide and narrow nest areas respectively, and found that when kept in polyandrous trios, females laid their egg clutches exactly at the borderline between the two regions each male could access. In contrast, females in pairs laid their clutches in either the wide or narrow area depending on the size of their mating partner. Our results demonstrate that polyandrous females carefully choose egg deposition site, increasing the direct benefits they receive from mating partners by using environmental structures to manipulate paternity. In this way, externally fertilising J. transcriptus manipulate male behaviour in a manner similar to cryptic female choice in internally fertilising animals. [ABSTRACT FROM AUTHOR]

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 capensis, are able to produce diploid female offspring via thelytokous parthenogenesis and thus produce clones of themselves. As a result, worker reproduction and tolerance towards worker-produced offspring is expected to be more permissive than in arrhenotokous (sub)species where worker offspring are male. Here we quantify the extent to which A. m. capensis workers contribute to reproduction in queenright colonies using microsatellite analyses of pre-emergent brood. We show that workers produced 10.5% of workers and 0.48% of drones. Most of the workers’ contribution towards the production of new workers coincided with the colonies producing new queens during reproductive swarming. [ABSTRACT FROM AUTHOR]

The article presents a study that examines the group membership decisions of Neolamprologus pulcher, a group-living cichlid. Also studied are the aggressive, submissive and social interactions between focal and resident helpers. The authors discovered the preference of subordinate helpers for joining familiar groups while helpers opted groups containing larger, more dominant individuals despite receiving more aggression within the group. The results highlighted the complex decision process in N. pulcher when choosing among groups.