In phylogenetics, the crown group of a collection of species consists of the living representatives of the collection together with their ancestors back to their last common ancestor as well as all of that ancestor's descendants. It is thus a clade, a group consisting of a species and all its descendents.
The name was given by Willi Hennig, the formulator of phylogenetic systematics, as a way of classifying living organisms relative to extinct ones. Though formulated in the 1970s, the term was not commonly used until its reintroduction in the 2000s by Graham Budd and Sören Jensen.
Read more about Crown Group: Contents of The Crown Group, Other Groups Under The Crown Group Concept, Palaeontological Significance of Stem- and Crown Groups, Stem-groups in Systematics
Famous quotes containing the words crown and/or group:
“To be a king and wear a crown is more glorious to them that see it than it is pleasure to them that bear it.”
—Elizabeth I (1533–1603)
“Even in harmonious families there is this double life: the group life, which is the one we can observe in our neighbour’s household, and, underneath, another—secret and passionate and intense—which is the real life that stamps the faces and gives character to the voices of our friends. Always in his mind each member of these social units is escaping, running away, trying to break the net which circumstances and his own affections have woven about him.”
—Willa Cather (1873–1947)