Evolutionary Associations of Endosymbiotic Ciliates Shed Light on the Timing of the Marsupial-Placental Split.

ABSTRACT: Trichostome ciliates are among the most conspicuous protists in the gastrointestinal tract of a large variety of vertebrates. However, little is still known about phylogeny of the trichostome/vertebrate symbiotic systems, evolutionary correlations between trichostome extrinsic traits, and character-dependent diversification of trichostomes. These issues were investigated here, using the relaxed molecular clock technique along with stochastic mapping of character evolution, and binary-state speciation and extinction models. Clock analyses revealed that trichostomes colonized the vertebrate gastrointestinal tract ∼135 Ma, that is, near the paleontological minimum for the split of therian mammals into marsupials and placentals. According to stochastic mapping, the last common ancestor of tric

SUBMITTER: Vdacny P 

PROVIDER: S-EPMC5995207 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature