Out of the blue: adaptive visual pigment evolution accompanies Amazon invasion.

ABSTRACT: Incursions of marine water into South America during the Miocene prompted colonization of freshwater habitats by ancestrally marine species and present a unique opportunity to study the molecular evolution of adaptations to varying environments. Freshwater and marine environments are distinct in both spectra and average intensities of available light. Here, we investigate the molecular evolution of rhodopsin, the photosensitive pigment in the eye that activates in response to light, in a clade of South American freshwater anchovies derived from a marine ancestral lineage. Using likelihood-based comparative sequence analyses, we found evidence for positive selection in the rhodopsin of freshwater anchovy lineages at sites known to be important for aspects of rhodopsin function such as spect

SUBMITTER: Van Nynatten A 

PROVIDER: S-EPMC4528450 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature