Data from: Imperfect morphological convergence: variable changes in cranial structures underlie transitions to durophagy in moray eels

Convergence is central to the study of evolution because it demonstrates
the power of natural selection to deterministically shape phenotypic
diversity. However, the conditions under which a common morphology
repeatedly evolves may be restrictive. Many factors—such as differing
genetic and environmental backgrounds and many-to-one mapping of form to
function—contribute to variability in responses to selection.
Nevertheless, lineages may evolve similar, even if not identical, forms
given a shared selective regime, providing opportunities to examine the
relative importance of natural selection, constraint and contingency.
Here, we show that following 10 transitions to durophagy in moray eels
(Muraenidae), cranial morphology repeatedly evolved toward a novel region
of morphological space indicative of enhanced feeding performance on hard
prey. Disparity among the resulting 15 durophagous species, however, is
greater than disparity among ancestors that fed on large evasive prey,
contradicting the pattern expected under convergence. This elevated
disparity is a consequence of lineage-specific responses to durophagy, in
which independent transitions vary in the suites of traits exhibiting the
largest changes. Our results reveal a pattern of imperfect convergence,
which suggests shared selection may actually promote diversification
because lineages often differ in their phenotypic responses to similar
selective demands.