Carotenoid-producing haloarchaea impart a red color to salt ponds in San Francisco Bay.WIKIMEDIA, GROMBO
While mutation and sexual reproduction drive genetic innovation in many eukaryotes, for life’s exclusively unicellular domains—archaea and bacteria—horizontal gene transfer is a critical mechanism for gaining new traits. And genes acquired from bacteria appear to have played an important role in forming major taxa of archaea, according to a phylogenetic analysis of more than 25,000 archaeal gene families. The study, published today (October 15) in Nature, also suggests that genetic transfers from bacteria to archaea are at least five times more common than from archaea to bacteria.
“We tend to think of evolution as proceeding in a gradual fashion, with the drip, drip, drip of point mutations accumulating along different lineages, and that leads to differentiation and new species,” said study coauthor William Martin of ...
