CROWN GROUP Meaning and
Definition
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A "crown group" refers to a concept in evolutionary biology and paleontology that designates a specific group of organisms that includes all living species as well as their common ancestor. This terminology is often used to distinguish the extant species from their extinct relatives and to determine the point in evolutionary history from which the current lineage diverges.
The term "crown group" is employed to express the living representatives of a particular taxonomic group, thus forming the highest branch on the phylogenetic tree. It is important to note that only the living organisms and their immediate extinct descendants are considered as part of the crown group, excluding any other extinct lineages that do not fall directly within this ancestral branch.
The concept of a crown group is significant for evolutionary biologists as it indicates the direct evolutionary lineage leading up to the contemporary species. By focusing on a crown group, scientists are able to identify and analyze the inherited traits and characteristics that have been passed down through generations, providing valuable insights into evolutionary history and dynamics.
In conclusion, a crown group represents the living organisms and their immediate extinct relatives that share a common ancestor. This concept allows scientists to distinguish and examine the direct evolutionary lineage leading up to the present-day species.
Etymology of CROWN GROUP
The term "crown group" originated from the field of evolutionary biology and systematics. It was first introduced by the British evolutionary biologist James Alfred Robinson in his 1971 paper titled "Roots and stems of flowering plants: Strobilanthopsis and the origin and early evolution of the angiosperms". Although the term "crown group" was not explicitly used in the paper, the concept behind it was described.
The term "crown group" was later formally coined by the American paleontologist Niles Eldredge and the British evolutionary biologist Gareth Nelson in their 1975 paper titled "Taxonomic Paleobiology: With Special Reference to the Study of Biological Diversification". They used the term to refer to the living members of a particular taxonomic group and all of its extinct descendants.
