remains include scales from ischnacanthiform acanthodians Gomphonchus sandelensis, Poracanthodes punctatus and Nostolepis striata, as well as acanthodian spine and tooth whorl fragments.
Increased global trade of live fish increases the risk that gnathostomes
and other fish-borne parasites will be introduced into regions along with their introduced hosts.
microRNAs reveal the interrelationships of hagfish, lampreys, and gnathostomes
and the nature of the ancestral vertebrate.
Similarities between the two branches of gnathostomes
provide an insight into the last common ancestor of jawed vertebrates.
The group gnathostomes
, meaning "jaw-mouths," includes tens of thousands of living vertebrate species, ranging from fish and sharks to birds, reptiles, mammals and humans.
Duguay et al  studied the Divergence of insulin-like growth factors I and II in the elasmobranch Squalus acanthias and observed that the prototypical IGF molecule duplicated and diverged in an ancestor of the extant gnathostomes
. According to Reinecke et al  in most bony fish species with the exception of Cottus, IGF-1 and insulin display a distinct cellular distribution, similar to that of mammals which may indicate that the branching of IGF-1 and insulin has occurred at the phylogenetic level of bony fish.
For example, humans are included in the following nested clades (using the informal names): eukaryotes, animals, deuterostomes, vertebrates, gnathostomes
, tetrapods, amniotes, mammals, eutherians, primates, monkeys, apes, and great apes (see Dawkins, 2004 for more information on the ancestry of humans).
(1995) The forebrain of gnathostomes
: in search of a morphotype.