Ecology of flowering and fruiting in Lotus corniculatus L.

Lotus corniculatus L. (Legtuninosae), is a perennial herb common throughout Britain. Its main pollinators are bumblebees (Bombus spp., Apidae: Hymenoptera). This is a study of the ecological factors which are important to flowering and fruiting in the species, and some of their evolutionary implications. The work was carried out at Wytham Estate, Oxfordshire, U.K., mainly in an ex-arable field (Upper Seeds) and a more established grassland (Lower Seeds Reserve). The literature on self-incompatibility in L. corniculatus is reviewed; there are conflicting reports, but wild material is fundamentally self-incompatible. Plants in Upper Seeds are larger than in Lower Seeds Reserve. Comparative data on soil nutrients in the two sites suggests that the cause is the persistence of phosphorus from inorganic fertiliser. There is a positive, linear relationship between plant size, flower production and fruit production. The species regulates investment in flowers mainly at the level of the whole inflorescence, rather than altering number of flowers per inflorescence. Within individuals, there are no consistent trade-offs between number of fruit per infructescence, numbers of seeds per fruit and seed weight. Weather patterns only partially explain the flowering phenology of L. corniculatus. Timing of first flowering and peak flowering are correlated but are variable between individuals, and between years for the same individuals. They are not correlated with flowering synchrony. An individual's flowering pattern does not consistently affect fruit-set; the overriding determinant of fruit production is plant size. Selection is therefore unlikely to be acting on flowering time in this species. The production of large numbers of self-incompatible flowers does not seem to reduce fruit-set; pollinators do not visit enough flowers per foraging trip (perhaps because nectar production is low) for geitonogamy to become a problem. Seed predation by larvae of a chalcid wasp, a weevil and a moth differs between individual plants, but not consistently so between years. Seed predation is not consistently correlated with plant size, mean flowers per inflorescence, number of seeds per fruit or seed size. There is no evidence for selection acting on these traits through seed predation. Partially predated seeds are often viable, which may have implications for seedling demography. Seed predation and flowering phenology are not defmitively linked, strengthening the argument that flowering time is not adaptive in this species

Constructions Of Equality In A Mathematics Classroom.

This thesis is a personal research journey, made through reflective anecdotes about notable events in classrooms. Explicit statements of my values as a teacher emerge from this analysis of my practice. There are four main chapters: Classroom Atmosphere identifies elements inherent in my interactions with children; Curriculum Development accounts for the change in my pedagogy from a scheme-based to a problem-solving approach; Teaching and Learning examines my perceptions of the different ways children learn mathematics and the types of strategies I have developed to support their learning; Issues on working with un-settled groups provides a historical perspective on my mixed-ability teaching and explores my rationale in differentiating children's learning outcomes through accessible starting points and a range of extension tasks. Throughout my research I pay attention both to children's academic and emotional development, and consider how issues relating to the content of the curriculum, to differential rates of learning, to how learning is fostered, and issues of non-selectivity of children within learning groups are inextricably linked. A key task has been to show the interconnectedness of issues, whilst demonstrating my understanding of each as a separate issue. The evidence from my research demonstrates that it is both feasible and valid to provide children with their entitlement to equal opportunities in learning mathematics without separating them into pre-determined ability groups which are self-fulfilling, limiting and inherently discriminatory

Robust Approximation to Adaptive Control by Use of Representative Parameter Sets with Particular Reference to Type 1 Diabetes

This paper describes an approach to adaptive optimal control in the presence of model parameter calculation difficulties. This has wide application in a variety of biological and biomedical research and clinical problems. To illustrate the techniques, the approach is applied to the development and implementation of a practical adaptive insulin infusion algorithm for use with patients with Type 1 diabetes mellitus

Extinctions of aculeate pollinators in Britain and the role of large-scale agricultural changes

Pollinators are fundamental to maintaining both biodiversity and agricultural productivity, but habitat destruction, loss of flower resources, and increased use of pesticides are causing declines in their abundance and diversity. Using historical records we assessed the rate of extinction of bee and flower-visiting wasp species in Britain, from the mid 19th century to the present. The most rapid phase of extinction appears to be related to changes in agricultural policy and practice beginning in the 1920s, before the agricultural intensification prompted by the Second World War, often cited as the most important driver of biodiversity loss in Britain. Slowing of the extinction rate from the 1960s onwards may be due to prior loss of the most sensitive species and/or effective conservation programs

Mathematical white lies

Colin Foster and Mike Ollerton discuss the complexities of making 'always-true' mathematical statements in the classroom

The origins of flowering plants and pollinators

For more than a century there has been a fascination with the surprisingly rapid rise and early diversity of flowering plants (angiosperms). Darwin described the seemingly explosive diversification of angiosperms as an “abominable mystery,” and debates continue about the origin and processes driving angiosperm speciation. Dating the origin of angiosperms was traditionally the prerogative of paleobotanists who read the fossil record of plants, but with DNA sequencing becoming increasingly sophisticated, molecular dating methods have come to the table. Many angiosperm fossils can be dated to the Early Cretaceous (∼135 million years ago), which has led paleobotanists to reason that they originated during that era. It is now increasingly recognized that angiosperms are probably older than the oldest fossils, but how much older remains controversial. When angiosperms originated is key to understanding the origin and evolution of pollinators, particularly insects such as bees, butterflies, moths, and flies

Press freedom is necessary to advance environmental protections across the globe

Journalists face increasing threats and obstacles to investigating environmental conditions internationally. In new research, Jeff Ollerton, Matt Walsh and Ted Sullivan find that press freedom goes hand in hand with a higher level of environmental protection. Therefore, for countries to address the climate crisis, they need an open, well-resourced media

Press freedom is necessary to advance environmental protections across the world

Journalists face increasing threats and obstacles to investigating environmental conditions internationally. In new research, Jeff Ollerton, Matt Walsh and Ted Sullivan find that press freedom goes hand in hand with a higher level of environmental protection. Therefore, for countries to address the climate crisis, they need an open, well-resourced media

Network analysis of phenological units to detect important species in plant-pollinator communities: can it inform conservation strategies?

Conservation of species is often focused either only on those that are endangered, or on maximising the number recorded on species lists. However, species share space and time with others, thus interacting and building frameworks of relationships that can be unravelled by community-level network analysis. It is these relationships that ultimately drive ecosystem function via the transfer of energy and nutrients. However interactions are rarely considered in conservation planning. Network analysis can be used to detect key species ("hubs") that play an important role in cohesiveness of networks. We applied this approach to plant-pollinator communities on two montane Northern Apennine grasslands, paying special attention to the modules and the identity of hubs. We performed season-wide sampling and then focused the network analyses on time units consistent with plant phenology. After testing for significance of modules, only some modules were found to be significantly segregated from others. Thus, networks were organized around a structured core of modules with a set of companion species that were not organized into compartments. Using a network approach we obtained a list of important plant and pollinator species, including three Network Hubs of utmost importance, and other hubs of particular biogeographical interest. By having a lot of links and high partner diversity, hubs should convey stability to networks. Due to their role in the networks, taking into account such key species when considering the management of sites could help to preserve the greatest number of interactions and thus support many other species

Insect pollinators boost the market price of culturally important crops: holly, mistletoe and the spirit of Christmas

Animal pollination is a vital ecological process in both natural and agricultural ecosystems. Economic valuation studies have demonstrated that pollination services may underpin a significant proportion of global crop market outputs. However these assessments are probably under-estimates because they have rarely included non-food crops, for which very few data are currently available. In particular, culturally symbolic plants have received no attention. Here we show that pollinators have considerable economic benefits to sales of European holly and mistletoe, two seasonal cultural crops that are almost wholly dependent upon insect pollinators for the production of ornamental berries. Analyses of a time series of auction records spanning 11 years indicates that wholesale prices paid for holly with berries are twice those paid for the crop without berries, whilst mistletoe with berries sells for almost three times the price of the crop lacking fruit. The benefits of this insect pollination ecosystem service to this market are therefore considerable. These findings demonstrate that pollinators can play a significant role in adding value to crops that provide resources other than food. In the future such crops should be included in assessments of regional and global value of animal pollination to increase the accuracy of assessments of the value of pollination as an ecosystem service. Our results also support arguments for continued efforts to conserve pollinator diversity and abundance in agro-ecological systems, not least for their contribution as providers of ecosystem services