Loss of a morph is associated with asymmetric character release in a radiation of woodland salamanders

Color polymorphism, the occurrence of multiple discrete color morphs with co-adapted sets of traits within the same population, may provide the raw materials for rapid species formation. It has been hypothesized that fixation of a single morph can result in character release, whereby the monomorphic form evolves without the constraint of accommodating multiple adaptive peaks. However, rates of evolution between populations fixed for different morphs likely depend on the specific adaptive zones occupied by each morph. We studied the evolution of dorsal color polymorphism (striped and unstriped morphs) in woodland salamanders (Plethodon), a North American radiation in which the polymorphism can be found in even the most distantly related species (~44 Ma divergence). We estimated a phylogenomic tree of Plethodon, representing all extant taxa and including multiple samples across the range of most species. Morphometric data suggest that between-species variation exists predominantly along a..., , # Loss of a morph is associated with asymmetric character release in a radiation of woodland salamanders

Dataset DOI: [10.5061/dryad.bvq83bknf](10.5061/dryad.bvq83bknf)

## Description of the data and file structure

Supplementary Appendix and tables as well as phylogenomic trees and morphological data used for analyses of woodland salamanders (genus: *Plethodon*). README.txt files below are also included within subfolders which explain data files and their contents.

Discrete character states throughout files refer to whether species were scored as unstriped (\"U\"), striped (\"S\"), polymorphic (\"S+U\"), or other (\"other\") under a given classification scheme, which account for uncertainty in assignment and are detailed in the publication. Eight schemes used these four color morph states (\"Discrete4a\" through \"Discrete4h\"), whereas alternative schemes considered only three states (\"Discrete3a\" through \"Discrete3d\") or two states (\"Discrete2a\" through \"Discrete2c\").

### Supplementary Appen...,