Testes asymmetry, condition and sexual selection in birds: an experimental test

The functional significance of the marked directional asymmetry in testes size observed in many bird species is obscure. Møller suggested that (i) the smaller of the two testes serves a compensatory role and increases in size (and hence reduces asymmetry) when the larger one is defective in some way, and (ii) as a consequence, the degree of directional asymmetry in testes size reflects male quality and covaries positively with the expression of secondary sexual traits.We conducted an experimental test of these two hypotheses in the zebra finch,Taeniopygia guttata. Neither hypothesis was supported. First, there was no significant relationship between the size of the left testis and relative testes asymmetry. Second, we obtained no support for the hypothesis that the degree of directional asymmetry in testes mass covaried with condition. On the contrary, directional asymmetry in testes mass was signifcantly greater in birds whose condition was experimentally reduced, compared with control birds. Moreover, we found no significant relationships between testes asymmetry and secondary sexual traits. We conclude that directional asymmetry in testes size does not reflect male condition in the zebra finch

Functional generalized autoregressive conditional heteroskedasticity

Heteroskedasticity is a common feature of financial time series and is commonly addressed in the model building process through the use of ARCH and GARCH processes. More recently multivariate variants of these processes have been in the focus of research with attention given to methods seeking an efficient and economic estimation of a large number of model parameters. Due to the need for estimation of many parameters, however, these models may not be suitable for modeling now prevalent high-frequency volatility data. One potentially useful way to bypass these issues is to take a functional approach. In this paper, theory is developed for a new functional version of the generalized autoregressive conditionally heteroskedastic process, termed fGARCH. The main results are concerned with the structure of the fGARCH(1,1) process, providing criteria for the existence of a strictly stationary solutions both in the space of square-integrable and continuous functions. An estimation procedure is introduced and its consistency verified. A small empirical study highlights potential applications to intraday volatility estimation

Does public consultation truly end? the Murray-Darling Basin experience

Over the last decade Australian governments at all levels have been changing governance arrangements for the management of natural resources and the environment. Government has been devolving some of its power and responsibility to the community to manage regionally significant ecological regions. Communities have, through their actions, demanded this power from their government with the establishment of movements such as Landcare. Individual community members now have an opportunity to make real, observable environmental changes to their region. Where a centralised Federal or State government does not address local issues with the same sense of ownership or sensitivity. With the partial sale of Telstra the Federal government established the Natural Heritage Trust, which in its first incarnation was designed to fund small on-ground natural resource management projects. This action has empowered the community to undertake the work that it feels is appropriate in its region. It removed government from the delivery function of small environmentally beneficial works and given the community greater responsibility. It is within this changing attitude by government that the Murray-Darling Basin Commission (MDBC) 1 operates to manage natural resources throughout the Murray- Darling Basin. The MDBC acknowledges that natural resource management is about people and their acceptance of suitable management regimes. To ensure that the community has a voice the Murray-Darling Basin Ministerial Council established a Community Advisory Committee to keep it informed of current community thinking on issues of natural resource management and provide recommendations on potential activities. This involvement of the community in the governance of natural resources is a recurring theme of the work of the MDBC. The community is involved to varying degrees of formality (and success) in the development of numerous crossborder, Basin wide strategies and operational plans. The two case studies contained in this report which were run via the MDBC on behalf of its partner governments show how the community can be engaged and what are the long term effects of engaging the community on issues of interest. The case studies show that the government when engaging the community will need to consider what happens with an engaged community once the ‘consultation’ has finished

Anaphoric resolution of zero pronouns in Chinese in translation and reading comprehension

The primary aim of the thesis is to investigate some of the processes of reading Chinese text by means of comparing and analysing approximately 100 parallel translations of four texts from Chinese to English. The translations are answers to A Level examination questions. The focus of the investigation is interpretation of the zero pronoun, a common phenomenon in Chinese, which often requires explicitation when translated into English. The secondary aim is to show how translation gives evidence of comprehension, as shown by the variation in interpretation of zero pronouns. The thesis reviews relevant psycholinguistic research into reading, particularly reading of Chinese text. This is followed by reviews of relevant research into translation as a reading activity, and a discussion of its role in language teaching and testing.The core of the thesis is the discussion of the zero pronoun in Chinese, including discussion of anaphoric choice - the writer's decision on when to use zero in preference to an explicit anaphoric form - and of anaphoric resolution - how a reader decides what a zero pronoun refers to. Anaphoric resolution may be problematic for less experienced readers of Chinese owing to its lack of rich morphological inflection which, in other languages, provides the reader with information. Some of the key ideas on anaphoric choice and resolution are then applied to the analysis of the data in the parallel translations. It would appear that factors in Chinese texts which have an effect on comprehending zero pronouns are antecedent distance, topic persistence, abstraction, multiplicity of arguments and the meaning of the verb. Characteristics of the reader which may affect comprehension of the zero pronoun include personal schemata which may lead to elaborative inferences. On the basis of the data I suggest that mark schemes could be devised on a scalar system encompassing optimal solution, proximal solution and nonsolution, which might help to solve the problem of variability in marking translation.A by-product of the thesis, and an avenue for further research, is the apparent close relationship between idea units, clause length, punctuation breaks and antecedent distance in Chinese texts and saccade length and working memory capacity in the reader of Chinese

PAC-Bayesian Treatment Allocation Under Budget Constraints

This paper considers the estimation of treatment assignment rules when the policy maker faces a general budget or resource constraint. Utilizing the PAC-Bayesian framework, we propose new treatment assignment rules that allow for flexible notions of treatment outcome, treatment cost, and a budget constraint. For example, the constraint setting allows for cost-savings, when the costs of non-treatment exceed those of treatment for a subpopulation, to be factored into the budget. It also accommodates simpler settings, such as quantity constraints, and doesn't require outcome responses and costs to have the same unit of measurement. Importantly, the approach accounts for settings where budget or resource limitations may preclude treating all that can benefit, where costs may vary with individual characteristics, and where there may be uncertainty regarding the cost of treatment rules of interest. Despite the nomenclature, our theoretical analysis examines frequentist properties of the proposed rules. For stochastic rules that typically approach budget-penalized empirical welfare maximizing policies in larger samples, we derive non-asymptotic generalization bounds for the target population costs and sharp oracle-type inequalities that compare the rules' welfare regret to that of optimal policies in relevant budget categories. A closely related, non-stochastic, model aggregation treatment assignment rule is shown to inherit desirable attributes.Comment: 70 pages, 7 figure

Nestling diet, secondary sexual traits and fitness in the zebra finch

We examined the effect of nestling diet quality on a suite of physiological, morphological and life-history traits in adult male zebra finches,Taeniopygia guttata. Compared with birds reared on a supplemented diet, nestlings reared on a seed-only diet showed a reduced rate of growth and reduced cell-mediated immune function as measured by an in vivo response to aT lymphocyte-dependent mitogen. There were no differences between birds reared on the two diets in any of the following adult traits: body size, primary sexual traits (testes mass, numbers of stored sperm, sperm function, velocity and morphology), secondary sexual traits (beak colour and song rate), serological traits or immunological traits. The only differences we detected were a lower body mass and a greater proportion of individuals with plumage abnormalities among those reared on a seed-only diet (this latter effect was transient). The fact that male zebra finches reared on a seed-only diet were, as adults, virtually indistinguishable from those reared on a supple- mented diet, despite having reduced growth and immune function as nestlings, demonstrates that they subsequently compensated through the di¡erential allocation of resources. Our results indicate that differ- ential allocation is costly in terms of fitness since birds reared on a seed-only diet experienced a significantly greater mortality rate than those reared on a supplemented diet. This in turn suggests the existence of a trade-of between the development of traits important for reproduction, such as primary and secondary sexual traits and longevity

Ejaculate allocation by male sand martins, Riparia riparia

Males of many species allocate sperm to ejaculates strategically in response to variation in the risk and intensity of sperm competition. The notable exception is passerine birds, in which evidence for strategic allocation is absent. Here we report the results of a study testing for strategic ejaculate allocation in a passerine bird, the sand martin (Riparia riparia). Natural ejaculates were collected from males copulating with a model female. Ejaculates transferred in the presence of a rival male contained significantly more sperm than ejaculates transferred in the absence of a rival male. There was no evidence that this difference was due to the confounding effects of the year of ejaculate collection, the identity of the model female, the colony, the stage of season or the period of the day in which ejaculates were collected. A more detailed examination of the ejaculate patterns of individual males, achieved by the DNA profiling of ejaculates, provided additional evidence for strategic allocation of sperm

Extent of microplastics in Pacific Sand Lance burying habitat in the Salish Sea

Extent of microplastics in Pacific Sand Lance burying habitat in the Salish Sea Willem Peters MRM candidate Simon Fraser University, Dr. Cliff Robinson Department of Fisheries and Oceans, Dr. Karen Kohfeld Simon Fraser University, Dr. Marlow Pellatt Parks Canada, Dr. Doug Bertram Environment and Climate Change Canada School of Resource and Environmental Management, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6 CANADA, [email protected] The ingestion of microplastics by forage fish and their subsequent accumulation and transfer up the coastal food web is a growing concern to scientists, government, fisheries, and the health sector. One key forage species in the Salish Sea, the Pacific sand lance (Ammodytes personatus), buries in low silt, medium coarse sand patches from chart datum to 100 m depth. In the southern Salish Sea near Sidney, several of these burying habitats are located in the vicinity of sewage discharge pipes and may be subject to microplastic accumulation. This research assesses the level of microplastic accumulation in Pacific sand lance burying habitats in the Salish Sea. Seafloor sediment samples were collected in Spring-Fall 2017, using a Van Veen grab sampler. Samples were collected at different distances from shore and effluent discharge pipes, and from a variety of depths and tidal currents. Microplastic concentrations were determined from the sediment samples in the laboratory using standard methods, while controlling for contamination. The main results indicate a significant correlation between suitable Pacific sand lance burying habitat and higher microplastic concentrations. We also found a strong imbalance of microplastic type and colour, with blue fibres making up the majority of microplastics found. The relationship between microplastics and Pacific sand lance habitat suitability is not intuitive in that higher concentrations of microplastics were found in sediments that suggest higher current rates, where settling dynamics would suggest that fewer particles would settle. Possible explanations include evacuation of microplastics from sand lance when buried, the proximity of suitable habitat to effluent discharge, or other as yet unexplored factors. Overall, the presence of microplastics in the burying habitats and stomachs of Pacific sand lance (as noted in other research) indicates more research is required to understand the implication to higher trophic level species that feed upon Pacific sand lance, such as chinook and coho salmon, various groundfish, fish-eating alcids, and marine mammals such as the humpback whale. Ultimately, strategies to reduce microplastics entering the Salish Sea will need to be implemented

A 5,000-Year Fire History in the Strait of Georgia Lowlands, British Columbia, Canada

Improved knowledge of long-term fire regimes and climate-fire-human relationships are important for effective management of forested ecosystems. In this study, we use two, high-resolution sedimentary-charcoal records to provide new, mid to late Holocene fire histories for the driest forests in south coastal British Columbia, Canada: Somenos Lake in the Moist Maritime Coastal Douglas Fir (CDFmm) forests on southeastern Vancouver Island and Chadsey Lake in the Dry Maritime Coastal Western Hemlock (CWHdm) forests in the central Fraser Valley. Peak fire frequency at Somenos Lake in southeast Vancouver Island was highest prior to 3,500 cal yr BP at 9.5 fires per 1,000 years (at ~4,500 cal yr BP), with a mean fire return interval of 188 years (122–259) and 24 fire peaks for the 4,855 year record. Peak fire frequency at Chadsey Lake in the Fraser Valley of the Lower Mainland of BC was highest (5.9) at 2,736 cal yr BP but fairly uniform from ~4,300 to 2,500 cal yr BP. The mean fire return interval at Chadsey Lake was 214 years (150–285) with 15 fire peaks for the ~4,258 year record. The fire history for Chadsey Lake appears to be strongly tied to broad regional climate patterns for the region whereas the variability in the Somenos Lake fire record displays a more complex pattern likely the result of the interplay between climatic and anthropogenic factors. Our results show how different age models using long- vs. short-term temporal scales of analysis can affect fire history interpretation and highlight the importance of considering spatial variability when interpreting mechanisms driving fire activity in this region

Speeding up deep neural architecture search for wearable activity recognition with early prediction of converged performance

Neural architecture search (NAS) has the potential to uncover more performant networks for human activity recognition from wearable sensor data. However, a naive evaluation of the search space is computationally expensive. We introduce neural regression methods for predicting the converged performance of a deep neural network (DNN) using validation performance in early epochs and topological and computational statistics. Our approach shows a significant improvement in predicting converged testing performance over a naive approach taking the ranking of the DNNs at an early epoch as an indication of their ranking on convergence. We apply this to the optimization of the convolutional feature extractor of an LSTM recurrent network using NAS with deep Q-learning, optimizing the kernel size, number of kernels, number of layers, and the connections between layers, allowing for arbitrary skip connections and dimensionality reduction with pooling layers. We find architectures which achieve up to 4% better F1 score on the recognition of gestures in the Opportunity dataset than our implementation of DeepConvLSTM and 0.8% better F1 score than our implementation of state-of-the-art model Attend and Discriminate, while reducing the search time by more than 90% over a random search. This opens the way to rapidly search for well-performing dataset-specific architectures. We describe the computational implementation of the system (software frameworks, computing resources) to enable replication of this work. Finally, we lay out several future research directions for NAS which the community may pursue to address ongoing challenges in human activity recognition, such as optimizing architectures to minimize power, minimize sensor usage, or minimize training data needs