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Purpose: The authors assessed common content knowledge of health-related fitness in a national representative sample of preservice physical education teachers in the United States. Methods: Six hundred and twenty-one preservice physical education teachers from 68 physical education teacher education (PETE) programs located in different regions in the United States completed the 40 multiple choice items health-related fitness knowledge test during the semester prior to their student teaching. In addition, each PETE program coordinator/department head completed the PETE Program Information Questionnaire. Results: The mean percentage correct on the test was 61.3% (M = 24.5, SD = 4.9). Analyses of variance and t-test analyses indicated that common content knowledge of health-related fitness was not a function of sex, program size, or region of the United States. Discussion/Conclusions: These data suggest that preservice physical education teachers in the United States lack common content knowledge of health-related fitness and warrant the attention of PETE programs.

Rhodopsin is the visual pigment responsible for initiating the phototransduction cascade in vertebrate rod photoreceptors. Although well-characterized in a few model systems, comparative studies of rhodopsin function, particularly for nonmammalian vertebrates are comparatively lacking. Bowerbirds are rare among passerines in possessing a key substitution, D83N, at a site that is otherwise highly conserved among G protein-coupled receptors. While this substitution is present in some dim-light adapted vertebrates, often accompanying another unusual substitution, A292S, its functional relevance in birds is uncertain. To investigate functional effects associated with these two substitutions, we use the rhodopsin gene from the great bowerbird (Ptilonorhynchus nuchalis) as a background for site-directed mutagenesis, in vitro expression and functional characterization. We also mutated these sites in two additional rhodopsins that do not naturally possess N83, chicken and bovine, for comparison. Both sites were found to contribute to spectral blue-shifts, but had opposing effects on kinetic rates. Substitutions at site 83 were found to primarily affect the kinetics of light-activated rhodopsin, while substitutions at site 292 had a larger impact on spectral tuning. The contribution of substitutions at site 83 to spectral tuning in particular depended on genetic background, but overall, the effects of substitutions were otherwise surprisingly additive, and the magnitudes of functional shifts were roughly similar across all three genetic backgrounds. By employing a comparative approach with multiple species, our study provides new insight into the joint impact of sites 83 and 292 on rhodopsin structure-function as well as their evolutionary significance for dim-light vision across vertebrates.