A non-policing honey bee colony (Apis mellifera capensis)

In the Cape honey bee Apis mellifera capensis, workers lay female eggs without mating by thelytokous parthenogenesis. As a result, workers are as related to worker-laid eggs as they are to queen-laid eggs and therefore worker policing is expected to be lower, or even absent. This was tested by transferring worker- and queen-laid eggs into three queenright A. m. capensis discriminator colonies and monitoring their removal. Our results show that worker policing is variable in A. m. capensis and that in one colony worker-laid eggs were not removed. This is the first report of a non-policing queenright honey bee colony. DNA microsatellite and morphometric analysis suggests that the racial composition of the three discriminator colonies was different. The variation in policing rates could be explained by differences in degrees of hybridisation between A. m. capensis and A. m. scutellata, although a larger survey is needed to confirm this.     

Higher removal rate of eggs laid by anarchistic queens—a cost of anarchy?

Anarchy, where honeybee workers produce males in the presence of a queen, is extremely rare in natural honeybee populations, suggesting that there are colony-level costs associated with being anarchistic. Yet, no significant costs have yet been identified. A possible reason for this may be that researchers have only focused on the behaviour of anarchistic workers, which have been shown to perform worker-tasks as do wild-type workers. Possibly, therefore, costs associated with anarchy should be sought in anarchistic queens and not workers. A potential cost could be a lower survival rate of eggs laid by anarchistic queens perhaps because their egg-marking signal is not as clear as that of a wild-type queen. In this paper, we determined the removal rate of eggs laid by anarchistic queens in standard worker-policing bioassays. Our results show that eggs laid by anarchistic queens are removed at a higher rate than eggs laid by wild-type queens. This does not seem to be due to differences in hydrocarbons found on the surface of eggs, as both egg types showed the same alkanes and alkenes in similar proportions. We postulate that higher removal rates of queen-laid eggs due to recognition errors may be one reason that anarchy is rare in natural honeybee populations.     

Dance precision of <Emphasis Type="Italic">Apis florea</Emphasis>—clues to the evolution of the honeybee dance language?

All honeybee species make use of the waggle dance to communicate the direction and distance to both food sources and potential new nest sites. When foraging, all species face an identical problem: conveying information about profitable floral patches. However, profound differences in nesting biology (some nest in cavities while others nest in the open, often on a branch or a cliff face) may mean that species have different requirements when dancing to advertise new nest sites. In cavity nesting species, nest sites are a precise location in the landscape: usually a small opening leading to a cavity in a hollow tree. Dances for cavities therefore need to be as precise as possible. In contrast, when the potential nest site comprises a tree or perhaps seven a patch of trees, precision is less necessary. Similarly, when a food patch is advertised, dances need not be very precise, as floral patches are often large, unless they are so far away that recruits need more precise information to be able to locate them. In this paper, we study the dance precision of the open-nesting red dwarf bee Apis florea. By comparing the precision of dances for food sources and nest sites, we show that A. florea workers dance with the same imprecision irrespective of context. This is in sharp contrast with the cavity-nesting Apis mellifera that increases the precision of its dance when advertising a potential new home. We suggest that our results are in accordance with the hypothesis that the honeybees’ dance communication initially evolved to convey information about new nest sites and was only later adapted for the context of foraging.     

Moving home: nest-site selection in the Red Dwarf honeybee (<Emphasis Type="Italic">Apis florea</Emphasis>)

The Red Dwarf honeybee (Apis florea) is one of two basal species in the genus Apis. A. florea differs from the well-studied Western Hive bee (Apis mellifera) in that it nests in the open rather than in cavities. This fundamental difference in nesting biology is likely to have implications for nest-site selection, the process by which a reproductive swarm selects a new site to live in. In A. mellifera, workers show a series of characteristic behaviors that allow the swarm to select the best nest site possible. Here, we describe the behavior of individual A. florea workers during the process of nest-site selection and show that it differs from that seen in A. mellifera. We analyzed a total of 1,459 waggle dances performed by 197 scouts in five separate swarms. Our results suggest that two fundamental aspects of the behavior of A. mellifera scouts—the process of dance decay and the process of repeated nest site evaluation—do not occur in A. florea. We also found that the piping signal used by A. mellifera scouts to signal that a quorum has been reached at the chosen site, is performed by both dancing and non-dancing bees in A. florea. Thus, the piping signal appears to serve a different purpose in A. florea. Our results illustrate how differences in nesting biology affect the behavior of individual bees during the nest-site selection process.     

Lack of interspecific parasitism between the dwarf honeybees Apis andreniformis and Apis florea

The dwarf honeybees Apis florea and Apis andreniformis are sympatric in Southeast Asia. We examined undisturbed nests of both species finding that heterospecific workers are present in some nests at low frequency. This suggested that workers may enter heterospecific nests as a prelude to reproductive parasitism. To test this hypothesis, we created mixed-species colonies and determined the reproductive response of workers within them based on molecular markers. In queenless colonies, workers of both species activated their ovaries at equal frequency. However, the majority species, A. florea, had complete reproductive dominance over A. andreniformis, most likely because the A. florea workers recognised and removed heterospecific larvae. In queenright mixed-species colonies, workers responded to heterospecific signals of the presence of the queen and did not activate their ovaries. Thus, despite predictions from kin selection theory that workers would benefit from parasitising heterospecific nests, we find no evidence that selection has established a parasitic strategy in these sibling species.     

Ethical Tools to Support Systematic Public Deliberations about the Ethical Aspects of Agricultural Biotechnologies

This special issue of the Journal of Agricultural and Environmental Ethics presents so-called ethical tools that are developed to support systematic public deliberations about the ethical aspects of agricultural biotechnologies. This paper firstly clarifies the intended connotations of the term “ethical tools” and argues that such tools can support liberal democracies to cope with the issues that are raised by the application of genetic modification and other modern biotechnologies in agriculture and food production. The paper secondly characterizes the societal discussion on agricultural biotechnology and defends the thesis that normative perspectives fuel this discussion, so one cannot come to grips with this discussion if one neglects these perspectives. The paper thirdly agrues that no such thing exists as “one” societal debate in which these issues should be discussed. There are several interwined debates, and different actors participate in different discourses. Some practical instruments are necessary in order to include the right issues in these debates. These instruments will be coined as “ethical tools,” since they are practical instruments that can be used (tools) in order to support debates and deliberative structures for a systematic engagement with ethical issues (hence, ethical tools). Finally, the paper clarifies the ethics of these ethical tools and presents the tools as discussed in the remainder of this special issue: 1) tools to include ethical issues in public consulation and involvement; 2) tools to support systematic reflection upon ethical issues in decision-making; and 3) tools to support explicit communication about values in the food chain.     

Sustainable Development and Future Generations

This paper argues, mainly on thebasis of Rawls's savings principle,Wissenburg's restraint principle, Passmore'schains of love, and De-Shalit'stransgenerational communities, for a doubleinterpretation of sustainable development as aprinciple of intergenerational justice and afuture-oriented green ideal. This doubleinterpretation (1) embraces the restraintprinciple and the argument that no individualcan claim an unconditional right to destroyenvironmental goods as a baseline that couldjustify directive strategies for governmentintervention in non-sustainable lifestyles, and(2) suggests that people's concerns about thedeterioration of nature and the environmentarticulate future-oriented narratives ofself-identity that could fuel non-directivestrategies to develop further responsibilitiestowards nearby future generations. Sustainabledevelopment, thus, provides sound arguments torestrict people's freedom to follow their ownlifestyles, when these lifestyles transgressedthe baseline of the restraint principle.However, the individual freedom of choiceshould not be restricted for any furtherenvironmental considerations. Non-directivestrategies are thus to stimulate thedevelopment of such further responsibilitiestowards nearby future generations.     

Environmental Utilization Space Between Science and Politics

This paper addresses the issue of operationalizing, or quantifying, sustainable development as a practical guideline for day-to-day environmental policy-making. It criticizes attempts at quantifying some environmental utilization space and argues that the uncertainty of scientific knowledge about the unintended environmental repercussions of consumptive choices casts serious doubt about attempts to justify government intervention in non-sustainable lifestyles.