Nectar distribution and its relation to food quality in honeybee (Apis mellifera) colonies

In honeybees (Apis niellifera), the process of nectar collection is considered a straightforward example of task partitioning with two subtasks or two intersecting cycles of activity: (1) foraging and (2) storing of nectar, linked via its transfer between foragers and food processors. Many observations suggest, however, that nectar colleclion and processing in honeybees is a complex process, involving workers of other sub-castes and depending on variables such as resource profitability or the amount of stored honey. It has been observed that food processor bees often distribute food to other hive bees after receiving it from incoming foragers, instead of storing it immediately in honey cells. While there is little information about the sub-caste affiliation and the behaviour of these second-order receivers, this stage may be important for the rapid distribution of nutrients and related information. To investigate the identity of these second-order receivers, we quantified behaviours following nectar transfer and compared these behaviours with the behaviour of average worker hive-bees. Furthermore, we tested whether food quality (sugar concentration) affects the behaviour of the second-order receivers. Of all identified second-order receivers, 59.3% performed nurse duties, 18.5% performed food-processor duties and 22.2% performed forager duties. After food intake, these bees were more active, had more trophallaxes (especially offering contacts) compared to average workers and they were found mainly in the brood area, independent of food quality. Our results show that the liquid food can be distributed rapidly among many bees of the three main worker sub-castes, without being stored in honey cells first. Furthermore, the results suggest that the rapid distribution of food partly depends on the high activity of second-order receivers.

Noble gas, CFC and other geochemical evidence for the age and origin of the Bath thermal waters, UK

The city of Bath is a World Heritage site and its thermal waters, the Roman Baths and new spa development rely on undisturbed flow of the springs (45 °C). The current investigations provide an improved understanding of the residence times and flow regime as basis for the source protection. Trace gas indicators including the noble gases (helium, neon, argon, krypton and xenon) and chlorofluorocarbons (CFCs), together with a more comprehensive examination of chemical and stable isotope tracers are used to characterise the sources of the thermal water and any modern components. It is shown conclusively by the use of 39Ar that the bulk of the thermal water has been in circulation within the Carboniferous Limestone for at least 1000 years. Other stable isotope and noble gas measurements confirm previous findings and strongly suggest recharge within the Holocene time period (i.e. the last 12 kyr). Measurements of dissolved 85Kr and chlorofluorocarbons constrain previous indications from tritium that a small proportion (<5%) of the thermal water originates from modern leakage into the spring pipe passing through Mesozoic valley fill underlying Bath. This introduces small amounts of O2 into the system, resulting in the Fe precipitation seen in the King’s Spring. Silica geothermometry indicates that the water is likely to have reached a maximum temperature of between 69–99 °C, indicating a most probable maximum circulation depth of ∼3 km, which is in line with recent geological models. The rise to the surface of the water is sufficiently indirect that a temperature loss of >20 °C is incurred. There is overwhelming evidence that the water has evolved within the Carboniferous Limestone formation, although the chemistry alone cannot pinpoint the geometry of the recharge area or circulation route. For a likely residence time of 1–12 kyr, volumetric calculations imply a large storage volume and circulation pathway if typical porosities of the limestone at depth are used, indicating that much of the Bath-Bristol basin must be involved in the water storage.

Perfecting Imperfect Duties via Institutionalization

Onora O’Neill’s thesis that, in a world like ours, institutionalization is a necessary condition for the existence of typical universal welfare rights—the “institutionalization thesis” for short—has often been criticized. I believe that most of these criticisms fail to appreciate that the institutionalization thesis is based on her “classical” understanding of rights, which stresses the essential duty-implying character of rights. By and large, O’Neill’s thesis stands and falls with the classical theory of rights. My suggestion is, therefore, that what is really at issue between O’Neill and at least some of her critics is the proper understanding of the concept of a right.

Approaching diplomatic and courtly gift-giving in Europe and Mughal India. Shared practices and cultural diversity

This article deals with courtly gift-giving practices in Europe and Mughal India from a comparative and interwoven perspective. Given the historiographical lacunae on Mughal gift-giving, the article presents preliminary observations for further research. Unlike most contributions to this volume, this article understands the notion of diversity in terms of an intercultural diversity that came to the fore in courtly contexts and in diplomatic encounters. My arguments are bifold. On the one hand, European and Mughal rulers and their envoys shared a common ground of diplomatic gift-giving practices that were shaped by an understanding of what was worthy of giving and of the symbolic power of the given objects. On the other hand, courtly gift-giving practices were embedded in different social and cultural environments in Europe and India. By looking at the notion of the ‘gift’ and the social organisation of the Mughal elite, it becomes clear that pīshkash was an idiosyncratic concept in South and Central Asian contexts and that offerings of manṣabdārs to the Mughal emperor had a different character than those of European courtiers to their rulers.