Data from: Evidence for complex life cycle constraints on salamander body form diversification

Metazoans display a tremendous diversity of developmental patterns,
including complex life cycles composed of morphologically disparate
stages. In this regard, the evolution of life cycle complexity promotes
phenotypic diversity. However, correlations between life cycle stages can
constrain the evolution of some structures and functions. Despite the
potential macroevolutionary consequences, few studies have tested the
impacts of life cycle evolution on broad-scale patterns of trait
diversification. Here we show that larval and adult salamanders with a
simple, aquatic-only (paedomorphic) life cycle had an increased rate of
vertebral column and body form diversification compared to lineages with a
complex, aquatic-terrestrial (biphasic) life cycle. These differences in
life cycle complexity explain the variations in vertebral number and adult
body form better than larval ecology. In addition, we found that lineages
with a simple terrestrial-only (direct developing) life cycle also had a
higher rate of adult body form evolution than biphasic lineages, but still
10-fold lower than aquatic-only lineages. Our analyses demonstrate that
prominent shifts in phenotypic evolution can follow long-term transitions
in life cycle complexity, which may reflect underlying stage-dependent
constraints.