62 resultados para news worker
Resumo:
Lasioglossum malachurum, a bee species common across much of Europe, is obligately eusocial across its range but exhibits clear geographic variation in demography and social behaviour. This variation suggests that social interactions between queens and workers, opportunities for worker oviposition, and patterns of relatedness among nest mates may vary considerably, both within and among regions. In this study, we used three microsatellite loci with 12–18 alleles each to examine the sociogenetic structure of colonies from a population at Agios Nikolaos Monemvasias in southern Greece. These analyses reveal that the majority of colonies exhibit classical eusocial colony structure in which a single queen mated to a single male monopolizes oviposition. Nevertheless, we also detect low rates of multiqueen nest founding, occasional caste switching by worker-destined females, and worker oviposition of both gyne and male-producing eggs in the final brood. Previous evidence that the majority of workers show some ovarian development and a minority (17%) have at least one large oocyte contrasts with the observation that only 2–3% of gynes and males (the so-called reproductive brood) are produced by workers. An evaluation of the parameters of Hamilton's Rule suggests that queens benefit greatly from the help provided by workers but that workers achieve greater fitness by provisioning and laying their own eggs rather than by tending to the queen's eggs. This conflict of interest between the queen and her workers suggests that the discrepancy between potential and achieved worker oviposition is due to queen interference. Comparison of relatedness and maternity patterns in the Agios Nikolaos Monemvasias population with those from a northern population near Tübingen, Germany, points to a north–south cline of increasingly effective queen control of worker behaviour.
Resumo:
Kin selection models of intracolonial conflict over the maternity of males predict that social hymenopteran workers should favour the production of sons and nephews over brothers when the effective mating frequency (me) of the queen is low (me2. Stingless bees have been used to support these models in that me within the group is considered low and workers are thought often to monopolise the parentage of males. We genetically analysed 20 worker and 20 male pupae from each of 10 colonies of the stingless bee Scaptotrigona postica (= Scaptotrigona aff. depilis) using six microsatellite loci and demonstrate queen monandry in eight nests and apparent low me in the other two. However, four colonies contained an additional matriline, possibly due to queen supersedure (serial polygyny), which complicated their genetic structure. Across colonies, workers were responsible for the maternity of 13% of all males. These data are broadly in agreement with predictions from kin selection theory, though the question remains open as to why workers do not secure a greater share of male maternity in this and other stingless bee species in which workers are more closely related to nephews than brothers.
Resumo:
Evolutionary conflicts among social hymenopteran nestmates are theoretically likely to arise over the production of males and the sex ratio. Analysis of these conflicts has become an important focus of research into the role of kin selection in shaping social traits of hymenopteran colonies. We employ microsatellite analysis of nestmates of one social hymenopteran, the primitively eusocial and monogynous bumblebee Bombus hypnorum, to evaluate these conflicts. In our 14 study colonies, B. hypnorum queens mated between one and six times (arithmetic mean 2.5). One male generally predominated, fathering most of the offspring, thus the effective number of matings was substantially lower (1–3.13; harmonic mean 1.26). In addition, microsatellite analysis allowed the detection of alien workers, those who could not have been the offspring of the queen, in approximately half the colonies. Alien workers within the same colony were probably sisters. Polyandry and alien workers resulted in high variation among colonies in their sociogenetic organization. Genetic data were consistent with the view that all males (n = 233 examined) were produced by a colony’s queen. Male parentage was therefore independent of the sociogenetic organization of the colony, suggesting that the queen, and not the workers, was in control of the laying of male-destined eggs. The population-wide sex ratio (fresh weight investment ratio) was weakly female biased. No evidence for colony-level adaptive sex ratio biasing could be detected.
Resumo:
Science based news is widely reported in the media. The ability to interact critically with such news reports is increasingly seen as a legitimate part of the science education agenda. This paper reports the findings of two studies looking at the early response and subsequent usage of a resource promoting the integration of science-based news in secondary science curriculum in Northern Ireland. This paper charts the introduction of the resource into schools. The subsequent impact on the science curriculum and the implications for teacher professional development are considered. Many science teachers demonstrate willingness and aptitude to use primary media sources within their teaching. Some who adopted the resource demonstrate the capacity to sustain the development using the resource as a catalyst in ongoing curricular change. Insights gained in this study are relevant to policy makers and curriculum developers as well as teachers seeking to promote this aspect of science education
Resumo:
Worldwide, science education reform is aiming to promote 'scientific literacy' among young people. Typically, this is taken to include empowering them to engage critically with science in news media. This study explored the extent and nature of secondary science teachers' use of newspapers. It found that, though a great many use the resource, the majority do so incidentally and with the intention of showing the relevance of the subject rather than developing their students' criticality.
Resumo:
Considers the use of premises in child protection and offers a model how they are constructed to avoid bias
Resumo:
A honeybee queen normally mates with 10-20 drones, and reproductive conflicts may arise among a colony's different worker patrilines, especially after a colony has lost its single queen and the workers commence egg laying. In this study, we employed microsatellite markers to study aspects of worker reproductive competition in two queenless Africanized honeybee colonies. First, we determined whether there was a bias among worker patrilines in their maternity of drones and, second, we asked whether this bias could be attributed to differences in the degree of ovary activation of workers. Third, we relate these behavioral and physiological factors to ontogenetic differences between workers with respect to ovariole number. Workers from each of three (colony A) and one (colony B) patrilineal genotypes represented less than 6% of the worker population, yet each produced at least 13% of the drones in a colony, and collectively they produced 73% of the drones. Workers representing these genotypes also had more developed follicles and a greater number of ovarioles per ovary. Across all workers, ovariole development and number were closely correlated. This suggests a strong effect of worker genotype on the development of the ovary already in the postembryonic stages and sets a precedent to adult fertility, so that