Countergradient variation in embryonic growth and development: do embryonic and juvenile performances trade off?

1. Countergradient variation in growth rate requires that rapid growth rate trades off with other performances, such that submaximal growth evolves in certain environments. Negative effects of rapid growth on other traits within a single ontogenetic stage are conspicuous candidates for such trade-offs, but trade-offs spanning ontogenetic stages have received much less attention. 2. We tested whether rapid growth and development of embryonic lizards was associated with poor juvenile performance, as estimated by growth rate and sprint speed after hatching. To do so, we raised lizards from three populations that differ in their environmental temperature and measured their performances during embryonic and hatchling stages. 3. Under the same environmental conditions, embryos from two cold environments grew and developed more rapidly than did the embryos from a warm environment. Among populations, rapid growth and development was associated with slow growth after hatching. But surprisingly, the opposite pattern was observed within populations. 4. Our results highlight the need to consider trade-offs mediated by ecological factors (e.g. competition and predation), which calls for similar experiments in natural environments.