Crown Group - Stem-groups in Systematics

Stem-groups in Systematics

As originally proposed by Karl-Ernst Lauterbach, stem-groups should be given the prefix "stem" (i.e. Stem-Aves, Stem-Arthropoda), however the crown group should have no prefix. The latter has not been universally accepted for known groups. A number of paleontologists have opted to apply this approach anyway.