Glossary of "Evolution (4th ed.)" by Futuyma & Kirkpatrick (2017)
- Derivation of the gene copies in one or more populations from a single ancestral copy viewed retrospectively (from the present back into the past).
Glossary of "Ancestors in Our Genome" by Harris (2015)
- proceeding back into evolutionary time, the confluence of two gene lineages into a single common ancestral gene.
- Futuyma, D. J. & Kirkpatrick, M. 2017. Evolution, 4th ed. -xviii + 602 pp. Sinauer Associates, Inc., Sunderland.
- Harris, E. E. 2015. Ancestors in Our Genome: the New Science of Human Evolution. - xx + 226 pp. Oxford University Press, New York.