in early Synapsids, although some later herbivorous dinosaurs, now extinct, also developed chewing, too. Today only modern mammals chew in the strictest sense of the word, but some fish species exhibit a somewhat similar behavior. By contrast, mastication is not found in any living birds, amphibians, or reptiles.

Premastication is sometimes performed by human parents for infants who are unable to do so for themselves. The food is masticated in the mouth of the