Abstract. -It is often proposed that the morphometric shape ofanimals often evolves as a correlated response to selection on life-history traits such as whole-body growth and differentiation rates. However, there exists little empirical information on whether selection on rates of growth or differentiation in animals could generate correlated response in morphometric shape beyond that owing to the correlation between these rates and body size. In this study genetic correlations were estimated among growth rate, differentiation rate, and body-size-adjusted head width in the green tree frog, Hyla cinerea. Head width was adjusted for size by using the residuals from log-log regressions of head width on snout-vent length. Size-adjusted head width at metamorphosis was positively genetically correlated with larval period length. Thus, size-independent shape might evolve as a correlated response to selection on a larval life-history trait. Larval growth rate was not significantly genetically correlated with size-adjusted head width. An additional morphometric trait, size-adjusted tibiofibula length, had a non normal distribution of breeding values, and so was not included in the analysis of genetic correlations (offspring from one sire had unusually short legs). This result is interesting because, although using genetic covariance matrices to predict longterm multivariate response to selection depends on the assumption that all loci follow a multivariate Gaussian distribution of allelic effects, few data are available on the distribution of breeding values for traits in wild populations. Size at metamorphosis was positively genetically correlated with larval period and larval growth rate. Quickly growing larvae that delay metamorphosis therefore emerge at a large size. The genetic correlation between larval growth rate andjuvenile (postmetamorphic) growth rate was near zero. Growth rate may therefore be an example of a fitness-related trait that is free to evolve in one stage of a complex life cycle without pleiotropic constraints on the same trait expressed in the other stage. Gould (1977) argued that morphometric shape in animals often evolves as a correlated response to selection on life-history traits such as whole-body rates ofgrowth or differentiation. This scenario is true by definition for shape variation that scales nonisometrically with overall body size (because if development rate variation causes size variation at the age or stage at which measurements are taken, then development rate is necessarily correlated with shape). It is not clear whether morphometric shape is genetically correlated with growth or differentiation rate independent ofbody size. Such a correlation would arise if the allometric relationship between shape and size is not constant, but is a function of development rate (e.g., changes in overall growth rate do not affect the growth rate of all body parts , Present address: Department of Biology, Sonoma State University, 180 I East Cotati Ave., Rohnert Park, CA 94928 USA.proportionately; ...