DNA passed to and from all kinds of organisms, even across kingdoms, has helped shape the tree of life, to a large and undisputed degree in microbes and also unexpectedly in multicellular fungi, plants, and animals.
Whiteflies overcome a toxin in plants they eat through the use of the plant’s own genetic protection, likely ferried from plant to insect millions of years ago by a virus.
A study of human populations around the world detects differing rates of horizontal gene transfer in the microbiome depending on what kind of society those people live in.