Ancestral salamanders likely had a biphasic life cycle. Hypothesizing that adaptations at one stage might limit adaptations at the other, Bonett and Blair (2017) studied rates of evolution of the basic body morphology of taxa with the ancestral biphasic cycle and those that are permanently aquatic and permanently terrestrial. Both had accelerated evolutionary rates relative to taxa that retain the ancestral life cycle, but rates were significantly higher in the aquatic as compared with the terrestrial taxa. This suggests that constraints on evolution can be stage-specific. Long-term shifts in life cycle complexity can have long lasting effects on phenotypic diversity in salamanders.