191 research outputs found

    The nesting of the Dark-billed Cuckoo in the Galapagos

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    Latino agricultural entrepreneurship pathways : Missouri profiles

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    "Profiles of Latino farmers in Missouri. Four groups identified. Group 1: Identified agriculture as the primary economic activity of one of the heads of the household. Group 2: Farmers with sales between 5,000and5,000 and 10,000. Group 3: Farmers with sales of less than $5,000. Group 4: Latinos engaged in agriculture with no sales. The profiles present the goals of each groups along with their demographic characteristics, capitals, and preferences for information."--Slide two

    The structure and function of diagrams in environmental design : a computational inquiry

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1989.Vita.Includes bibliographical references (leaves 252-261).by Stephen McTee Ervin.Ph.D

    Snake (Colubridae: Thamnophis) Predatory Responses to Chemical Cues from Native and Introduced Prey Species

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    Several aquatic vertebrates have been introduced into freshwater systems in California over the past 100 years. Some populations of the two-striped garter snake (Thamnophis hammondii) have lived in sympatry with these species since their introduction; other populations have never encountered them. To assess the possible adaptation to a novel prey, we tested the predatory responses of T. hammondii from different populations to different chemosensory cues from native and introduced prey species. We presented chemical extracts from potential prey types and 2 control odors to individual snakes on cotton swabs and recorded the number of tongue flicks and attacks directed at each swab. Subject response was higher for prey odors than control substances. Odors from introduced centrarchid fish (Lepomis) elicited higher response levels than other prey types, including native anuran larvae (Pseudacris regilla). The pattern of response was similar for both populations of snakes (experienced and naïve, with respect to the introduced prey). We suggest that the generalist aquatic lifestyle of T. hammondii has allowed it to take advantage of increasing populations of introduced prey. Decisions on the management strategies for some of these introduced prey species should include consideration of how T. hammondii populations might respond in areas of sympatry

    Grain sorghum production calendar

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    The Oklahoma Cooperative Extension Service periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311

    Outstanding challenges in the transferability of ecological models

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    Predictive models are central to many scientific disciplines and vital for informing management in a rapidly changing world. However, limited understanding of the accuracy and precision of models transferred to novel conditions (their ‘transferability’) undermines confidence in their predictions. Here, 50 experts identified priority knowledge gaps which, if filled, will most improve model transfers. These are summarized into six technical and six fundamental challenges, which underlie the combined need to intensify research on the determinants of ecological predictability, including species traits and data quality, and develop best practices for transferring models. Of high importance is the identification of a widely applicable set of transferability metrics, with appropriate tools to quantify the sources and impacts of prediction uncertainty under novel conditions
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