Digits lost or gained? Evidence for pedal evolution in the Dwarf salamander complex (Eurycea, Plethodontidae)

9Citations
Citations of this article
42Readers
Mendeley users who have this article in their library.

Abstract

Change in digit number, particularly digit loss, has occurred repeatedly over the evolutionary history of tetrapods. Although digit loss has been documented among distantly related species of salamanders, it is relatively uncommon in this amphibian order. For example, reduction from five to four toes appears to have evolved just three times in the morphologically and ecologically diverse family Plethodontidae. Here we report a molecular phylogenetic analysis for one of these four-toed lineages--the Eurycea quadridigitata complex (dwarf salamanders)--emphasizing relationships to other species in the genus. A multilocus phylogeny reveals that dwarf salamanders are paraphyletic with respect to a complex of five-toed, paedomorphic Eurycea from the Edwards Plateau in Texas. We use this phylogeny to examine evolution of digit number within the dwarf-Edwards Plateau clade, testing contrasting hypotheses of digit loss (parallelism among dwarf salamanders) versus digit gain (re-evolution in the Edwards Plateau complex). Bayes factors analysis provides statistical support for a five-toed common ancestor at the dwarf-Edwards node, favoring, slightly, the parallelism hypothesis for digit loss. More importantly, our phylogenetic results pinpoint a rare event in the pedal evolution of plethodontid salamanders.

Cite

CITATION STYLE

APA

Lamb, T., & Beamer, D. A. (2012). Digits lost or gained? Evidence for pedal evolution in the Dwarf salamander complex (Eurycea, Plethodontidae). PLoS ONE, 7(5). https://doi.org/10.1371/journal.pone.0037544

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free