Kiefertragenden

Kiefertragenden is a descriptive term used in German biology to denote organisms that possess jaws, i.e., gnathostomes. The word combines Kiefer (jaw) and tragend (bearing) and is used to distinguish jaw-bearing vertebrates from jawless forms. It is not a formal taxonomic group, but a functional or morphological label commonly found in educational texts and overviews of vertebrate evolution.

In taxonomy and anatomy, the term is typically applied to vertebrates with jaws, including cartilaginous fishes (Chondrichthyes), bony fishes (Osteichthyes), and all tetrapods (amphibians, reptiles, birds, mammals). The counterpart is kieferlose Formen, or cyclostomata, which include jawless vertebrates such as lampreys and hagfish. Some sources may refer to “kiefertragende Wirbeltiere” to denote Gnathostomata as a whole.

Etymology: the term is formed from the German words for jaw (Kiefer) and bearing (tragend), functioning as a descriptive label rather than a formal rank in the Linnaean system.

Evolution: jaws are believed to have evolved from modifications of the first pharyngeal arches. The earliest kiefertragenden vertebrates appeared in the late Silurian to early Devonian, roughly 430–420 million years ago, enabling new feeding strategies and contributing to significant diversification of vertebrate lineages.

See also: Gnathostomata; Cyclostomata; vertebrate evolution.