111 research outputs found

    Beyond words, yes, but also beyond numbers

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    Safina’s fascinating series of fifty separate feuilletons tries to bridge a painful Methodenstreit in contemporary ethology mainly by an accumulation of anecdotes. Some deal with his own dogs, but most derive from reading or conversing with observers of a wider range of social mammals including elephants, wolves, apes, and whales. In spite of the many interruptions by travesties of the academic lifestyle and its literature, there is a point to be made, concerning the centrality of evidence about cooperative behavior styles, especially aspects of child-rearing, for the understanding of “what animals think and feel.” But Safina’s argument would be a lot more persuasive, at least to this outsider, if he were more aware of his own methodological preferences and the restraints they impose on the rhetoric of scientific persuasion. In spite of my skepticism, I sketch a possible application of his ideas to human neuroteratology

    The ontogenetic complexity of developmental constraints

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    Developmental constraint is a theoretically important construct bridging ontogenetic and evolutionary studies. We propose a new operationalization of this notion that exploits the unusually rich measurement structure of landmark data. We represent landmark configurations by their partial warps, a basis for morphospace that represents a set of localized features of form. A finding of developmental constraint arises from the interplay between age-varying means and age-specific variances in these subspaces of morphospace. Examination of variances and means in 16 ventral skull landmarks in the cotton rat S. fulviventer at ages 1, 10, 20, and 30 days yielded three types of developmental constraint: canalization (constraint to relatively constant form age by age); chreods (reduction of variance orthogonal to the mean trajectory over ages); and opposition (reduction of age-specific variance along the mean trajectory over ages). While canalization and chreodic constraints have been noted previously, the oppositional type of constraint appears novel. Only one of our characters, relative length and orientation of the incisive foramen, appears to be canalized. Although skull growth becomes increasingly integrated through ontogeny, our characters display a remarkable spatiotemporal complexity in patterns of variance reduction. The specific assortment of constraints observed may be related to the precociality of Sigmodon . We suggest that Waddington's diagrammatic presentation of the “epigenetic landscape” may be misleading in quantitative studies of developmental regulation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73980/1/j.1420-9101.1993.6050621.x.pd

    Random walk and quantitative stratigraphical sequences

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    A sequence of digitized observations on short-normal resistivity determinations seems to show trend from higher to lower values. An appropriate statistical model proves it to have less range than expected on the distribution of its successive increments. On a two-tailed statistical procedure for testing deviations from a random walk, the series tends towards ‘stasis’ rather than trend. The random walk model is shown to be plausible for the problem considered.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73590/1/j.1365-3121.1992.tb00465.x.pd

    The Structure Of Individual Variation In Miocene Globorotalia

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137454/1/evo05209.pd

    Comment on "Issues related to the prediction of craniofacial growth"

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24561/1/0000842.pd

    Ontogeny Of Integrated Skull Growth In The Cotton Rat Sigmodon Fulviventer

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137530/1/evo00626.pd

    Physical Properties of Biological Entities: An Introduction to the Ontology of Physics for Biology

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    As biomedical investigators strive to integrate data and analyses across spatiotemporal scales and biomedical domains, they have recognized the benefits of formalizing languages and terminologies via computational ontologies. Although ontologies for biological entities—molecules, cells, organs—are well-established, there are no principled ontologies of physical properties—energies, volumes, flow rates—of those entities. In this paper, we introduce the Ontology of Physics for Biology (OPB), a reference ontology of classical physics designed for annotating biophysical content of growing repositories of biomedical datasets and analytical models. The OPB's semantic framework, traceable to James Clerk Maxwell, encompasses modern theories of system dynamics and thermodynamics, and is implemented as a computational ontology that references available upper ontologies. In this paper we focus on the OPB classes that are designed for annotating physical properties encoded in biomedical datasets and computational models, and we discuss how the OPB framework will facilitate biomedical knowledge integration
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