21 research outputs found

    Drosophila melanogaster grooming possesses syntax with distinct rules at different temporal scales.

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    Mathematical modeling of behavioral sequences yields insight into the rules and mechanisms underlying sequence generation. Grooming in Drosophila melanogaster is characterized by repeated execution of distinct, stereotyped actions in variable order. Experiments demonstrate that, following stimulation by an irritant, grooming progresses gradually from an early phase dominated by anterior cleaning to a later phase with increased walking and posterior cleaning. We also observe that, at an intermediate temporal scale, there is a strong relationship between the amount of time spent performing body-directed grooming actions and leg-directed actions. We then develop a series of data-driven Markov models that isolate and identify the behavioral features governing transitions between individual grooming bouts. We identify action order as the primary driver of probabilistic, but non-random, syntax structure, as has previously been identified. Subsequent models incorporate grooming bout duration, which also contributes significantly to sequence structure. Our results show that, surprisingly, the syntactic rules underlying probabilistic grooming transitions possess action duration-dependent structure, suggesting that sensory input-independent mechanisms guide grooming behavior at short time scales. Finally, the inclusion of a simple rule that modifies grooming transition probabilities over time yields a generative model that recapitulates the key features of observed grooming sequences at several time scales. These discoveries suggest that sensory input guides action selection by modulating internally generated dynamics. Additionally, the discovery of these principles governing grooming in D. melanogaster demonstrates the utility of incorporating temporal information when characterizing the syntax of behavioral sequences

    Flowers through insect eyes: the contribution of pollinator vision to the evolution of flower colour

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    PhDFlowers’ colours are an essential element of their ability to attract visits from pollinators. However, the colours as they appear to human observers can differ substantially from their appearance to insect pollinators, and so it is essential to consider pollinator vision in any study of the ecology of flower colour. In this thesis I describe how I have overseen the development of an online database to provide accurate information on floral spectral reflectance measured without human observational bias. This resource allows a more accurate consideration of flower colours in future studies, and permits investigations of flower colours within and across habitats. Using the records in this database, I analysed flowers from two European habitats for spatial or temporal changes, modelling the colours according to insect visual perception. I discovered that the insect-colour composition of the plant communities does not change either along an altitudinal gradient or throughout the year. These novel and ecologically-relevant analyses contradict previous observational studies, but support the theory of a pollination “market” in which flowers compete for pollinator visitation. I then describe my experimental investigations into the visual capabilities of two pollinators and how this may relate to what colours of flowers they visit. Firstly I study the foraging behaviour of bees under spatially inconsistent illumination and how this impacts on their choice behaviour. I revealed patchy light can have measurable effects on bee foraging behaviour: they intentionally choose familiar over unfamiliar illumination, which may impact on the flowers they visit in complex natural environments. Secondly, I detail the new evidence for a red-sensitive photoreceptor in South African monkey beetles, a major pollinator in a habitat containing many longwavelength- reflecting flowers, which are not classically “attractive” to bees. Throughout this thesis, I explore how pollinator vision has shaped the evolution of flower colours in different contexts.Biotechnology and Biological Science Research Council. Royal Botanical Gardens Kew (BBS/S/L-2005/12155A

    Writing Science Through Critical Thinking

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    Written and extensively class tested with NSF/NIH support, this timely and useful text addresses a crucial need which is acknowledged in most universities and colleges. It is the need for students to learn to write in the context of their field of study; in this case science. Although numerous how to writing books have been published, few, if any, address the central pedagogical issues underlying the process of learning to think and write scientifically. The direct connection between this writing skill and that of critical thinking is developed with engaging style by the author, an English professor. Moriarty\u27s book is an invaluable guide for both undergraduate and graduate science students. In the process of learning the specific requirements of organization demanded by scientific writing, students will develop strategies for thinking through their scientific research, well before they sit down to write. This instructive text will be useful to students who need to satisfy a science writing proficiency requirement in the context of a science course, a course in technical writing, advanced composition, or writing for the profession.https://digitalcommons.hollins.edu/facbooks/1047/thumbnail.jp

    Cultural Techniques: Assembling Spaces, Texts & Collectives

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    Addressing cultural techniques from different disciplinary perspectives, this volume elaborates upon a concept originally developed in media studies. In a series of case studies, it reconstructs the basic operations of spatialization underlying more complex symbolic artefacts and articulations, which range from techniques of the body to landscapes, from paperwork to encyclopedias, from collections to collectives
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