24 research outputs found
The Making of a Queen: TOR Pathway Is a Key Player in Diphenic Caste Development
Honey bees (Apis mellifera) provide a principal example of diphenic development. Excess feeding of female larvae results in queens (large reproductives). Moderate diet yields workers (small helpers). The signaling pathway that links provisioning to female developmental fate is not understood, yet we reasoned that it could include TOR (target of rapamycin), a nutrient- and energy-sensing kinase that controls organismal growth.Here, the role of Apis mellifera TOR (amTOR) in caste determination is examined by rapamycin/FK506 pharmacology and RNA interference (RNAi) gene knockdown. We show that in queen-destined larvae, the TOR inhibitor rapamycin induces the development of worker characters that are blocked by the antagonist FK506. Further, queen fate is associated with elevated activity of the Apis mellifera TOR encoding gene, amTOR, and amTOR gene knockdown blocks queen fate and results in individuals with worker morphology.A much-studied insect dimorphism, thereby, can be governed by the TOR pathway. Our results present the first evidence for a role of TOR in diphenic development, and suggest that adoption of this ancestral nutrient-sensing cascade is one evolutionary pathway for morphological caste differentiation in social insects
Insetos em presépios e as "formigas vestidas" de Jules Martin (1832-1906): uma curiosa manufatura paulistana do final do século XIX
Encontrados no Brasil desde os primórdios da colonização portuguesa, os presépios logo tiveram de adaptar-se à realidade local, circunstância muito propÃcia ao aparecimento de concepções heterodoxas e ao emprego de elementos exóticos da fauna e flora de cada região. Como registros envolvendo insetos são muito pouco comuns, chama a atenção que fêmeas de saúva, Atta sp. (Hymenoptera, Formicidae), tenham sido aproveitadas na composição de presépios no estado de São Paulo. Tendo subsistido pelo menos até a década 1960, os "presépios de formigas" existentes em cidades como Embu das Artes poderiam estar relacionados à s "formigas vestidas" criadas por Jules Martin, curiosa manufatura paulistana do último quartel do século XIX.Present in Brazil since the beginning of Portuguese colonization, crèche nativity scenes were soon adapted to local reality, a propitious circumstance for the appearance of heterodox conceptions and the use of exotic elements of the fauna and flora peculiar to each region. As records about insects are very uncommon, it is noteworthy that females of leaf-cutting ants, Atta sp. (Hymenoptera, Formicidae), were used to compose crèche nativity scenes in São Paulo State. Having subsisted at least up to the decade of 1960, the "ant crèches" of cities such as Embu das Artes could be related to the then famous "dressed ants" created by Jules Martin, a curious manufacture of the city of São Paulo in the last quarter of the 19th century
As estruturas territoriais dos insetos
AS SOCIEDADES de insetos utilizam muitos tipos de materiais e recursos biológicos para construir seus abrigos. As disposições espaciais e estruturas de apoio são criadas de forma engenhosa, oferecendo condições adequadas para a criação da prole, a produção ou o armazenamento de alimentos. A sua localização e as suas interconexões as inserem nas áreas circundantes, e elas podem aproveitar vantagens circunstanciais oferecidas pelo meio ambiente. As técnicas de construção e de manutenção fazem parte da cultura desses seres, e permitem uma visão interessante de soluções obtidas mediante a utilização eficiente de uma ampla gama de recursos disponÃveis.<br>INSECT SOCIETIES use many kinds of materials and biologic resources to build their shelters. Space arrangements and supporting structures are created in an ingenious way to provide adequate conditions for development of the young, for food production or storage. Their location and interconnections insert them into the surrounding areas, and they may take advantage of circumstantial benefits of their environment. Building and maintenance techniques belong to the culture of these beings, and they offer an interesting vision of solutions based on efficient use of a wide range of available resources
A Bug's Life: Competition Among Species Towards the Environment
A model of different species competing for the same environment is presented, and possible explanations of peaceful coexistence or rather internecine conflicts are consequently derived. By means of a Lotka-Volterra dynamic system we describe the evolution of two populations (bees and locusts) that differently approach the management of those natural resources they contend for, and thus make a simple parable of todays societies playing the current environmental scenario