Age polyethism in Plebeia emerina (Friese) (Hymenoptera: Apidae) colonies related to propolis handling

Stingless bees collect plant resins and make it into propolis, although they have a wider range of use for this material than do honey bees (Apis spp.). Plebeia spp. workers employ propolis mixed with wax (cerumen) for constructing and sealing nest structures, while they use viscous (sticky) propolis for defense by applying it onto their enemies. Isolated viscous propolis deposits are permanently maintained at the interior of their colonies, as also seen in other Meliponini species. Newly-emerged Plebeia emerina (Friese) workers were observed stuck to and unable to escape these viscous propolis stores. We examined the division of labor involved in propolis manipulation, by observing marked bees of known age in four colonies of P. emerina from southern Brazil. Activities on brood combs, the nest involucrum and food pots were observed from the first day of life of the marked bees. However, work on viscous propolis deposits did not begin until the 13th day of age and continued until the 56th day (maximum lifespan in our sample). Although worker bees begin to manipulate cerumen early, they seem to be unable to handle viscous propolis till they become older

A global-scale expert assessment of drivers and risks associated with pollinator decline.

Pollinator decline has attracted global attention and substantial efforts are underway to respond through national pollinator strategies and action plans. These policy responses require clarity on what is driving pollinator decline and what risks it generates for society in different parts of the world. Using a formal expert elicitation process, we evaluated the relative regional and global importance of eight drivers of pollinator decline and ten consequent risks to human well-being. Our results indicate that global policy responses should focus on reducing pressure from changes in land cover and configuration, land management and pesticides, as these were considered very important drivers in most regions. We quantify how the importance of drivers and risks from pollinator decline, differ among regions. For example, losing access to managed pollinators was considered a serious risk only for people in North America, whereas yield instability in pollinator-dependent crops was classed as a serious or high risk in four regions but only a moderate risk in Europe and North America. Overall, perceived risks were substantially higher in the Global South. Despite extensive research on pollinator decline, our analysis reveals considerable scientific uncertainty about what this means for human society.University of Reading’s Building Outstanding Impact Support Programm

Biocultural approaches to pollinator conservation

Pollinators underpin sustainable livelihoods that link ecosystems, spiritual and cultural values, and customary governance systems with indigenous peoples and local communities (IPLC) across the world. Biocultural diversity is a short-hand term for this great variety of people-nature interlinkages that have developed over time in specific ecosystems. Biocultural approaches to conservation explicitly build on the conservation practices inherent in sustaining these livelihoods. We used the Conceptual Framework of the Intergovernmental Platform on Biodiversity and Ecosystem Services to analyse the biocultural approaches to pollinator conservation by indigenous peoples and local communities globally. The analysis identified biocultural approaches to pollinators across all six elements of the Conceptual Framework, with conservation-related practices occurring in sixty countries, in all continents except Antarctica. Practices of IPLC that are significant for biocultural approaches to pollinator conservation can be grouped into three categories: the practice of valuing diversity and fostering biocultural diversity; landscape management practices; and diversified farming systems. Particular IPLCs may use some or all of these practices. Policies that recognise customary tenure over traditional lands, strengthen Indigenous and Community Conserved Areas, promote heritage listing and support diversified farming within a food sovereignty approach, are among several identified that strengthen biocultural approaches to pollinator conservation, and thereby deliver mutual benefits for pollinators and people

Safeguarding pollinators and their values to human well-being

Wild and managed pollinators provide a wide range of benefits to society in terms of contributions to food security, farmer and beekeeper livelihoods, social and cultural values, as well as the maintenance of wider biodiversity and ecosystem stability. Pollinators face numerous threats, including changes in land-use and management intensity, climate change, pesticides and genetically modified crops, pollinator management and pathogens, and invasive alien species. There are well-documented declines in some wild and managed pollinators in several regions of the world. However, many effective policy and management responses can be implemented to safeguard pollinators and sustain pollination services

The males of Melipona and other stingless bees, and their mothers

Female behaviour in social Hymenoptera and the queen-worker conflict with respect to male production have been the focus of many studies. Although male production is an investment that is in conflict with investment in colony size, males play a vital role in colony reproduction. This paper reviews the production patterns of male stingless bees, their activities once they have reached adulthood and their origin (i.e., are they sons of workers or of queens). The existence of a broad spectrum of species-specific patterns of male production, sex ratios, and male parentage offers ample opportunities to discuss the influence of ecology on the dynamics of stingless bee colony life. The paper also argues that selfishness causes the queen and the workers to compete and each to adopt certain strategies in their effort to produce male progeny. It is this competition, expressed in various forms during the characteristic and socially complex process of cell provisioning and oviposition, that could help explain the variable outcomes of male parentage at the species level as we currently know them

The polygyny of Melipona bicolor: scramble competition among queens

The stingless bee Melipona bicolor is facultatively polygynous, a unique character among the bees. Polygynous colonies were not more productive than monogynous colonies. During the process of provisioning and oviposition of cells (POP) a queen may be either alone or together with one or two other queens. If together, each queen has on average the same chance to lay the egg, indicating that there is no dominance mechanism involved. During the POP, a queen may ingest some of the larval food and a trophic egg laid by a worker. Worker egg laying is less frequent in multiple queen POPs. The most active queen has proportionally more single-queen POPs and more trophic eggs. Such nutritional advantage and the resulting output of eggs could depend on chance, but a lasting qualitative difference among queens probably exists as well. Though we could outline the mechanisms behind the outcome of this scramble competition for egg laying, the adaptive significance of this polygyny remains largely mysterious

Egg laying and oophagy by reproductive workers in the polygynous stingless bee Melipona bicolor (Hymenoptera, Meliponini)

We studied queen-worker conflict over male production in a Melipona bicolor colony, having three physogastric queens and individually marked workers, by means of observations of the processes of cell oviposition. The gender that developed from these cells showed that queens produced mainly female offspring. The overall percentage of the males that were workers' sons was estimated between 27 and 82%. Forty-two times workers were seen to deposit a male egg, normally following the queen's oviposition, in the same cell and in sixteen cases, the reproductive worker ate the egg already present in the cell before ovipositing in it. Workers not only were more likely to lay their egg next to that of another worker than next to a queen's egg, they also were more likely to replace the egg already present when it was worker-derived. Their conduct agrees with predictions from kin-selection theory because workers are better served when rearing sons at the cost of other workers' sons than at the cost of queens' daughters

MRI of the knee before and after arthroscopic synovectomy in patients with rheumatoid arthritis

The effectiveness of arthroscopic synovectomy (A-S) for the knee of rheumatoid arthritis (RA) patients was assesssd by comparing the severity of synovial proliferation on MRI before and after the surgery. Twenty-five patients (30 knees) were studied. The mean duration of RA was 6 years and 7 months and the mean age at the time of A-S was 49.0 years. The mean follow-up period was 19 months (range:6-39 months). The preoperative Larsen's classification from grade Ⅰto Ⅳ was 8, 13, 6, and 3 knees, resectively. Synovial proliferation was evaluated by the modified Takeuchi's classification (MRI score). The MRI score was investigated in relationships with the radiographic grade, wet weight of excised tissue, treatment score for RA knees of the Japanese Orthopaedic Association (JOA score), and the CRP value. The MRI score, JOA score, and CRP all significantly improved during follow-up. The radiographic grade showed less progression, the JOA score improved more, and CRP was lower during follow-up in patients with a postoperative MRI score less than 5. The wet weight of excised tissue showed no related with the MRI score. These results suggest that the effectiveness of A-S can be determined by evaluation of improvement of the MRI score