Data from: Different traits dominate evolution at early and late stages of adaptive radiation

Adaptive radiation (AR), a process of rapid speciation and
ecomorphological diversification, played an important role in generating
past and contemporary global biodiversity. An unsolved question is what
maintains high rates of speciation during AR, a phenomenon we call
“speciation paradox”. One possible explanation for resolving this paradox
is a sequential trait evolution, i.e., a series of ecological
diversifications, which enables evolving lineages to fully and more
effectively exploit the ecological space. We tested this hypothesis using
the highly diverse subterranean amphipod genus Niphargus. Niphargus shows
distinct signatures of adaptive radiation both at the genus level and at
the level of four larger clades. Our analysis revealed decoupled evolution
of habitat-related traits and trophic-biology-related traits. Moreover, on
a genus level, we found the evidence that AR commences with a tight
association between speciation rates and the dynamics of habitat-related
traits. At a later stage, speciation dynamics become associated with
diversification of trophic-biology-related traits. This suggests that the
dependence of macroevolutionary rates in this group switches
among niche axes before saturation, resulting in prolonged high speciation
rates during AR.