The ancient organisms appear to be more closely related to eukaryotes than previously appreciated.

Contrary to some hypotheses, the organelles did not descend from any known lineage of Alphaproteobacteria, researchers find.

From fish harvests to cottonwood forests, organisms display evidence that species change can occur on timescales that can influence ecological processes.

Viruses within Salmonella rapidly spread genes throughout the bacterial population during a gut infection, scientists show.

A bacterium’s ability to distinguish self from non-self can arise spontaneously, a study shows, reigniting questions of whether the trait can be considered an adaptation.

Strong selective pressure can lead to rapid and reproducible evolution in bacteria.

Animal family tree rearranged; how E. coli evades the immune system; pharmacological chaperones and misfolded proteins

Escherichia coli can quickly evolve to resist engulfment by macrophages, scientists have found.

In lab experiments, bacteria usurp small, damaged fragments of DNA, including those from a 43,000-year-old woolly mammoth.