Process
Evolution
The process by which living things change over generations through changes in their genomes.
Watching evolution in the lab: in a long-running E. coli experiment, one population evolved the ability to use citrate after about 31,500 generations.Source: Blount et al., 2008
Process
The process by which living things change over generations through changes in their genomes.
Organism or group
Small single-celled organisms without a nucleus, found almost everywhere on Earth. Most bacteria in the human body are harmless, and some are helpful.
The explanations on this page are our own summaries of these sources. Follow a link to read the original; if anything here disagrees with it, the original wins. How we choose and check sources.
Blount ZD, Borland CZ, Lenski RE (2008). Proceedings of the National Academy of Sciences 105:7899-7906.