Global network structure of dominance hierarchy of ant workers

Dominance hierarchy among animals is widespread in various species and believed to serve to regulate resource allocation within an animal group. Unlike small groups, however, detection and quantification of linear hierarchy in large groups of animals are a difficult task. Here, we analyse aggression-based dominance hierarchies formed by worker ants in Diacamma sp. as large directed networks. We show that the observed dominance networks are perfect or approximate directed acyclic graphs, which are consistent with perfect linear hierarchy. The observed networks are also sparse and random but significantly different from networks generated through thinning of the perfect linear tournament (i.e., all individuals are linearly ranked and dominance relationship exists between every pair of individuals). These results pertain to global structure of the networks, which contrasts with the previous studies inspecting frequencies of different types of triads. In addition, the distribution of the out-degree (i.e., number of workers that the focal worker attacks), not in-degree (i.e., number of workers that attack the focal worker), of each observed network is right-skewed. Those having excessively large out-degrees are located near the top, but not the top, of the hierarchy. We also discuss evolutionary implications of the discovered properties of dominance networks.Comment: 5 figures, 2 tables, 4 supplementary figures, 2 supplementary table

Gamergate controls dopamine levels of workers in <i>Diacamma</i> sp.

Introdução: O climatério representa uma fase de mudança e de transição no ciclo de vida feminino, durante o qual as mulheres experimentam alterações físicas e psicológicas decorrentes do hipoestrogenismo e envelhecimento. O Médico de Família é habitualmente o primeiro profissional de saúde a quem a mulher recorre para esclarecer as suas dúvidas e solicitar o alívio da sintomatologia climatérica, ocupando uma posição privilegiada para promover a capacitação e empowerment das utentes. Métodos: Promoveu-se um estudo observacional transversal, aplicando um questionário de auto-preenchimento a 92 mulheres, com idades compreendidas entre os 40 e os 60 anos, que frequentam os Centros de Saúde Norton de Matos e S. Martinho do Bispo (USF Mondego), de forma a avaliar a abordagem da menopausa nos Cuidados de Saúde Primários. A recolha dos dados decorreu de abril a julho de 2014. O tratamento estatístico foi efetuado através da plataforma estatística IBM SPSS v21.0. Resultados: Mais de metade das mulheres (55,4%) referiu ter conversado com o Médico de Família sobre a menopausa e todos os assuntos relacionados, todavia 19,6% ainda manifestavam dúvidas. O médico foi considerado a principal fonte de informação para 50% das inquiridas. A maioria das mulheres (77,2%) descreveu a presença de sintomas climatéricos, sendo os mais frequentes as dores ósseas (73,2%) e a ansiedade (67,6%). 39,1% das inquiridas indicaram a interferência do climatério na sua vida diária, sendo a vida familiar (69,4%) e a sexual (58,3%) as mais afetadas. Verificou-se uma associação significativa entre a presença de sintomas e a interferência do climatério na vida diária e na qualidade de vida da mulher. As mulheres sintomáticas (OR=12,983 com IC95% [2,808;60,033]) e as que referiram a interferência do climatério no dia a dia (OR=5,965 com IC95% [2,364;15,048]) apresentaram uma probabilidade aumentada de recorrer a consultas de Medicina Geral e Familiar. As infeções urinárias de repetição (91,7%) foram as queixas que mais motivaram a ida ao Médico de Família. Das mulheres sintomáticas, 45,1% referiram ter cuidados adicionais ou fazer algum tratamento. A terapêutica hormonal revelou-se a mais eficaz no alívio das queixas, tendo como prescritor mais frequente o Ginecologista (58,3%). Conclusão: O Médico de Família assume um papel crucial na capacitação e acompanhamento da mulher climatérica. Constatou-se que ainda permanecem dúvidas que necessitam de ser esclarecidas e que são necessárias normas que uniformizem a abordagem da menopausa na prática clínica.Introduction: The climacteric represents a time of change and transition in the female life cycle, during which women experience physical and psychological changes resulting from hypoestrogenism and aging. The general practitioner is usually the first health professional to whom a woman appeals to clarify her doubts and request relief from climacteric symptoms, occupying a privileged position to promote capacity building and empowerment of patients. Methods: It was promoted a cross-sectional observational study, applying a self-completion questionnaire to 92 women, aged between 40 and 60 years, who attend the health centers of Norton de Matos and S. Martinho do Bispo (USF Mondego), in order to evaluate the approach of menopause in Primary Health Care. Data collection took place from April to July 2014. The statistical analysis was performed by the statistical platform IBM SPSS v21.0. Results: More than half of women (55.4%) said they had talked to the general practitioner about menopause and all the related subjects, however 19.6% still had doubts. The doctor was considered the main source of information for 50% of the surveyed women. Most women (77.2%) described the presence of menopausal symptoms, the most common being bone pain (73.2%) and anxiety (67.6%). 39.1% of the surveyed indicated the interference of the climacteric in their everyday life, being the family life (69.4%) and the sexual life (58.3%) the most affected. There was a significant association between the presence of symptoms of menopause and the interference of the climacteric in daily life and quality of life. Symptomatic women (OR = 12.983 with 95% CI [2.808, 60.033]) and those who mentioned the interference of the climacteric in daily life (OR = 5.965 95% CI [2.364, 15.048]) had an increased likelihood of appealing to a general practitioner. Recurrent urinary tract infections (91.7%) were complaints that most commonly lead going to the general practitioner. Of symptomatic women, 45.1% said having additional care or getting some treatment. Hormone therapy proved more effective in relieving complaints, having the gynecologist as the most frequent prescriber (58.3%). Conclusion: The general practitioner plays a key role in the capacity building and monitoring of the climacteric woman. It was found that there are still questions that need to be clarified and that standards are necessary to standardize the approach of menopause in clinical practice

Expansion of presoldier cuticle contributes to head elongation during soldier differentiation in termites

In termites, the soldier caste possesses morphological features suitable for colony defence, despite some exceptions. Soldiers are differentiated via two moultings through a presoldier stage with dramatic morphogenesis. While a number of morphological modifications are known to occur during the presoldier moult, growth and morphogenesis seem to continue even after the moult. The present study, using the damp-wood termite Hodotermopsis sjostedti, carried out morphological and histological investigations on the developmental processes during the presoldier stage that is artificially induced by the application of a juvenile hormone analogue. Measurements of five body parameters indicated that head length significantly increased during the 14-day period after the presoldier moult, while it did not increase subsequently to the stationary moult (pseudergate moult as control). Histological observations also showed that the cuticular development played a role in the presoldier head elongation, suggesting that the soft and flexible presoldier cuticle contributed to the soldier morphogenesis in termites

Male neotenic reproductives accelerate additional differentiation of female reproductives by lowering JH titer in termites

Abstract Eusocial insects exhibit reproductive division of labor, in which only a fraction of colony members differentiate into reproductives. In termites, reproductives of both sexes are present in a colony and constantly engaged in reproduction. It has been suggested that the sex ratio of reproductives is maintained by social interactions. The presence of reproductives is known to inhibit the additional differentiation of same-sex reproductives, while it promotes the differentiation of opposite-sex reproductives. In this study, using the damp-wood termite Hodotermopsis sjostedti, physiological effects of male/female reproductives on the differentiation of supplementary reproductives (neotenics) were examined. The results showed that the only male-neotenic condition, i.e., the presence of male neotenics in the absence of female neotenics, accelerated the neotenic differentiation from female workers (i.e., pseudergates). Under this condition, the rise of juvenile hormone (JH) titer was repressed in females, and the application of a JH analog inhibited the female neotenic differentiation, indicating that the low JH titer leads to rapid differentiation. Thus, the only male-neotenic condition that actively promotes reproductive differentiation by manipulating physiological condition of females is suggested to be a mechanism underlying sexual asymmetry in reproductive function, which may lead the female-biased sex allocation of reproductives

Variation in the coat-color-controlling genes, Mc1r and Asip,in the house mouse Mus musculus from Madagascar

Variability in the coat color of the house mouse, Mus musculus, provides an opportunity to study the evolution of phenotypes in this species. Here we associated genetic variations with coat color in seven mice from Madagascar that had identical M. m. gentilulus mitochondrial DNA sequences. The entire coding region of the 948-base pair (bp) coat-color-related gene, Mc1r, was shown to have no nonsynonymous changes. However, analyses of the two exon-1 promoter regions—termed 1A (317 bp) and 1B (499 bp)—from a second gene, Asip, which is also involved in the evolution of coat color, revealed two distinct haplotypes in each region. Associations between Asip promoter regions and dorsal color were ambiguous; however, two ventral color types—light and dark gray—were associated with the haplotypes of 1A, as determined by clustering analysis. Notably, the haplotype of the light gray animals was identical to the Asip Aw allele that is associated with white bellies