The ontogenetic complexity of developmental constraints

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

The Structure Of Individual Variation In Miocene Globorotalia

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

Random walk and quantitative stratigraphical sequences

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

A Clinical atlas of roentgenographic measurements in Norma Frontalis . By Sudha Srikrishen Saksena. New York: Alan R. Liss, Inc. 1990. xvi + 252 pp., figures, tables, references. $65.00 (cloth)

No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/37651/1/1330830217_ftp.pd

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

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

Ontogeny Of Integrated Skull Growth In The Cotton Rat Sigmodon Fulviventer

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

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

Analysis of the Human Female Foot in Two Different Measurement Systems: From Geometric Morphometrics to Functional Morphology

The relationship of geometric morphometrics (GMM) to functional analysis of the same morphological resources is currently a topic of active interest among functional morphologists. Although GMM is typically advertised as free of prior assumptions about shape features or morphological theories, it is common for GMM findings to be concordant with findings from studies based on a-priori lists of shape features whenever prior insights or theories have been properly accounted for in the study design. The present paper demonstrates this happy possibility by revisiting a previously published GMM analysis of footprint outlines for which there is also functionally relevant information in the form of a-priori foot measurements. We show how to convert the conventional measurements into the language of shape, thereby affording two parallel statistical analyses. One is the classic multivariate analysis of »shape features«, the other the equally classic GMM of semilandmark coordinates. In this example, the two data sets, analyzed by protocols that are remarkably different in both their geometry and their algebra, nevertheless result in one common biometrical summary: wearing high heels is bad for women inasmuch as it leads to the need for orthotic devices to treat the consequently flattened arch. This concordance bears implications for other branches of applied anthropology. To carry out a good biomedical analysis of applied anthropometric data it may not matter whether one uses GMM or instead an adequate assortment of conventional measurements. What matters is whether the conventional measurements have been selected in order to match the natural spectrum of functional variation