“…In quantitative genetic studies, "size free" shape measures are often constructed using ratios, which have considerable statistical (Atchley et aI., 1976) and interpretative (Bookstein et aI., 1985;Strauss, 1985) problems that detract from their usefulness. However, there seems to be no relationship between relative variability and heritability among mensural traits in either the polychaete Pi/eolaria pseudomilitaris (Beckwitt, 1981) or the amphipod Gammarus minus (Fong, 1988), nor among a series of metric characters (Atchley et a!., 1981) and multivariate size and shape factors (Leamy and Thorpe, 1984) in strains of rats and mice. Even if they exist, such correlations are likely to be age dependent (Atchley and Rutledge, 1980).…”