The effect of forager loss on honeybee workers temporal polyethism and social network structure

The western honeybee Apis mellifera is perhaps the best-known example of an advanced eusocial species displaying temporal polyethism, a process in which workers perform different tasks in the colony as they age. Previous studies demonstrated that this temporal division of labour is not only regulated by the age of the bees but also by the proportion of workers performing the required tasks in the colony. As we progress through the Anthropocene, the Intergovernmental Panel on Climate Change predicted that a significant increase in both the frequency and intensity of severe weather events can be expected in the coming decades. Here, we performed a controlled interrupted time series experiment with the objective of quantifying the possible effects that these weather events might have in the honeybee colony dynamics. By simulating a significant loss of foragers in the colony, we observed that honeybee workers quickly replaced the missing foragers by accelerating their transition to a subsequent task and, in some cases, completely skipped several of the natural task transitions with respect to their age. In addition, we analysed how the colony social network structure is affected by the sudden loss of foragers. Indeed, our data show that honeybee colonies increased their network cohesion with workers having a higher number of interactions as well as becoming more closely connected to one another soon after the disturbance. Overall, our data shows that even when faced with a substantial perturbation, honeybees can respond swiftly in order to maintain colony homeostasis and likely increase their resilience against future perturbations

Longe dos partidos e perto da federação: uma avaliação dos gastos municipais na saúde pública

The institutionalization of SUS made the municipalities important players in the public health policy. Thus, it was expected that the amount of resources allocated to public health would be determinate in some measure by the political party preferences. Given these political and institutional contexts, we analyzed the importance of the political party policies at the municipality level as a determinant of the expenditure on public health, as well was other conventional determinants of the expenditures on public health (region, per capita income, GDP, etc). Applying some econometric techniques (quantile regressions and econometric decomposition), we found that the parties’ political preferences have minor influence on the allocation of resources in public health. We conclude that the constitutional regulation (Constitutional Emend 29 or EC29) seems to be a more important determinant to explain the allocation of resources in the period 2002-2006 than the supposed political preferences announced by parties.SUS, health economics, Brazil

Dual Effect of Wasp Queen Pheromone in Regulating Insect Sociality

SummaryEusocial insects exhibit a remarkable reproductive division of labor between queens and largely sterile workers [1, 2]. Recently, it was shown that queens of diverse groups of social insects employ specific, evolutionarily conserved cuticular hydrocarbons to signal their presence and inhibit worker reproduction [3]. Workers also recognize and discriminate between eggs laid by the queen and those laid by workers, with the latter being destroyed by workers in a process known as “policing” [4, 5]. Worker policing represents a classic example of a conflict-reducing mechanism, in which the reproductive monopoly of the queen is maintained through the selective destruction of worker-laid eggs [5, 6]. However, the exact signals used in worker policing have thus far remained elusive [5, 7]. Here, we show that in the common wasp, Vespula vulgaris, the pheromone that signals egg maternity and enables the workers to selectively destroy worker-laid eggs is in fact the same as one of the sterility-inducing queen signals that we identified earlier [3]. These results imply that queen pheromones regulate insect sociality in two distinct and complementary ways, i.e., by signaling the queen’s presence and inhibiting worker reproduction, and by facilitating the recognition and policing of worker-laid eggs

Diagnóstico dos produtores orgânicos da feira agroecológica do mercado municipal de Goiânia-GO

A agricultura orgânica é entendida como prática sustentável da agricultura, com manejo da produção minimamente ofensivo ao meio ambiente. Buscou-se neste trabalho identificar as práticas e motivações dos feirantes de produtos orgânicos em Goiânia. Foi realizado um censo com os comerciantes desta feira, utilizando questionários semi-estruturados, de onde foi extraído que todos os feirantes que comercializam produtos de origem vegetal in natura orgânicos possuem certificação pelo IBD, o mesmo não ocorrendo com produtos de origem animal ou produtos processados. Foi constatado também que a principal motivação para a prática de agricultura orgânica é a preocupação com a saúde, o que acaba sendo um atrativo para consumidores, que se tornaram fieis, e mantém o funcionamento do mercado de orgânicos em Goiânia, mesmo diante das dificuldades enfrentadas pelos feirantes

Perfil dos consumidores de produtos orgânicos da feira agroecológica do mercado municipal de Goiânia-GO

O presente trabalho analisa e discute o perfil do consumidor de produtos orgânicos da Feira Agroecológica do Mercado Municipal de Goiânia.  Utilizou-se como ferramenta de pesquisa um questionário semiestruturado. Os principais resultados observados foram: a preocupação quanto à saúde e a qualidade de vida pessoal e dos familiares; esses consumidores estão dispostos a pagar mais caro pelos produtos orgânicos certificados e também que o perfil cultural e socioeconômico desses consumidores é mais elevado do que a média nacional, pois, 84% dos entrevistados possuem curso superior com algum tipo de especialização. Foi possível concluir que a relação com a alimentação orgânica se deve à preocupação com a saúde e qualidade de vida

The origin and evolution of queen and fertility signals in Corbiculate bees

Abstract\ud \ud Background\ud In social Hymenoptera (ants, bees and wasps), various chemical compounds present on the cuticle have been shown to act as fertility signals. In addition, specific queen-characteristic hydrocarbons have been implicated as sterility-inducing queen signals in ants, wasps and bumblebees. In Corbiculate bees, however, the chemical nature of queen-characteristic and fertility-linked compounds appears to be more diverse than in ants and wasps. Moreover, it remains unknown how queen signals evolved across this group and how they might have been co-opted from fertility signals in solitary ancestors.\ud \ud \ud Results\ud Here, we perform a phylogenetic analysis of fertility-linked compounds across 16 species of solitary and eusocial bee species, comprising both literature data as well as new primary data from a key solitary outgroup species, the oil-collecting bee Centris analis, and the highly eusocial stingless bee Scaptotrigona depilis. Our results demonstrate the presence of fertility-linked compounds belonging to 12 different chemical classes. In addition, we find that some classes of compounds (linear and branched alkanes, alkenes, esters and fatty acids) were already present as fertility-linked signals in the solitary ancestors of Corbiculate bees, while others appear to be specific to certain species.\ud \ud \ud Conclusion\ud Overall, our results suggest that queen signals in Corbiculate bees are likely derived from ancestral fertility-linked compounds present in solitary bees that lacked reproductive castes. These original fertility-linked cues or signals could have been produced either as a by-product of ovarian activation or could have served other communicative purposes, such as in mate recognition or the regulation of egg-laying.RCO and CAO were supported by scholarships from CNPq-Brazil (238127/2012-5\ud and 201959/2012-7). RCO was supported by FWO (international mobility\ud V406714N). TW was supported by FWO and the KU Leuven Centre of Excellence\ud PF/2010/007, DAA was supported by FAPESP (2010/19717-4) and PNPD-CAPES.\ud TW and FN were supported by CNPq-Brazil (402661/2012-5). Special thanks to\ud Jelle van Zweden for the valuable comments and insights and to Prof. Jocelyn\ud Millar for providing us the synthetic aldehyde standards and for helping with the\ud chemical compounds identification

IgG Induced by Vaccination With Ascaris suum Extracts Is Protective Against Infection

Human ascariasis has a global and cosmopolitan distribution, and has been characterized as the most prevalent neglected tropical disease worldwide. The development of a preventive vaccine is highly desirable to complement current measures required for this parasitic infection control and to reduce chronic childhood morbidities. In the present study, we describe the mechanism of protection elicited by a preventive vaccine against ascariasis. Vaccine efficacy was evaluated after immunization with three different Ascaris suum antigen extracts formulated with monophosphoryl lipid A (MPLA) as an adjuvant: crude extract of adult worm (ExAD); crude extract of adult worm cuticle (CUT); and crude extract of infective larvae (L3) (ExL3). Immunogenicity elicited by immunization was assessed by measuring antibody responses, cytokine production, and influx of tissue inflammatory cells. Vaccine efficacy was evaluated by measuring the reductions in the numbers of larvae in the lungs of immunized BALB/c mice that were challenged with A. suum eggs. Moreover, lung physiology and functionality were tested by spirometry to determine clinical efficacy. Finally, the role of host antibody mediated protection was determined by passive transfer of serum from immunized mice. Significant reductions in the total number of migrating larvae were observed in mice immunized with ExL3 61% (p < 0.001), CUT 59% (p < 0.001), and ExAD 51% (p < 0.01) antigens in comparison with non-immunized mice. For the Ascaris antigen-specific IgG antibody levels, a significant and progressive increase was observed with each round of immunization, in association with a marked increase of IgG1 and IgG3 subclasses. Moreover, a significant increase in concentration of IL-5 and IL-10 (pre-challenge) in the blood and IL-10 in the lung tissue (post-challenge) was induced by CUT immunization. Finally, ExL3 and CUT-immunized mice showed a marked improvement in lung pathology and tissue fibrosis as well as reduced pulmonary dysfunction induced by Ascaris challenge, when compared to non-immunized mice. Moreover, the passive transfer of specific IgG antibodies from ExL3, CUT, and ExAD elicited a protective response in naïve mice, with significant reductions in parasite burdens in lungs of 65, 64, and 64%, respectively. Taken together, these studies indicated that IgG antibodies contribute to protective immunity

Una lliçó de resiliència : com les abelles s'adapten a les adversitats

Un estudi científic revela la impressionant adaptabilitat de les abelles de la mel davant desafiaments climàtics. Les colònies d'abelles ajusten ràpidament els seus rols interns i augmenten la comunicació dins la colònia durant esdeveniments climàtics extrems, assegurant un subministrament constant d'aliments. Aquesta troballa ressalta la resiliència de les abelles, però també els reptes preocupants que s'enfronten a causa del canvi climàtic.Un estudio científico revela la impresionante adaptabilidad de las abejas de la miel ante desafíos climáticos. Las colonias de abejas ajustan rápidamente sus roles internos y aumentan la comunicación dentro la colonia durante eventos climáticos extremos, asegurando un suministro constante de alimentos. Este hallazgo resalta la resiliencia de las abejas, pero también los retos preocupantes que se enfrentan debido al cambio climático.A recent scientific study reveals the impressive adaptability of honeybees to climate challenges. Bee colonies quickly adjust their internal roles and increase communication within the colony during extreme weather events, ensuring a constant food supply. This finding highlights the resilience of bees, but also the worrying challenges due to climate change

Chemical signals underlying cooperation and conflicts in insect societies ,,

nrpages: 188status: publishe