Rapid evolution of troglomorphic characters suggests selection rather than neutral mutation as a driver of eye reduction in cave crabs.

ABSTRACT: This study asked whether reductive traits in cave organisms evolve at a slower pace (suggesting neutral evolution under relaxed selection) than constructive changes, which are likely to evolve under directional selection. We investigated 11 subterranean and seven surface populations of Sundathelphusa freshwater crabs on Bohol Island, Philippines, and examined constructive traits associated with improved food finding in darkness (increased leg and setae length) and reductive traits (reduced cornea size and eyestalk length). All changes occurred rapidly, given that the age of the most recent common ancestor was estimated to be 722-271 ka based on three mitochondrial markers. In order to quantify the speed of character change, we correlated the degree of morphological change with genetic dist

SUBMITTER: Klaus S 

PROVIDER: S-EPMC3639761 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature