nonmammal
Nonmammal is a term used to describe any animal that is not a mammal. It is not a formal taxonomic group, but a broad, informal category used in biology, ecology, and everyday language to distinguish mammals from all other animals.
The nonmammal category encompasses a vast diversity of life, including birds, reptiles, amphibians, and fish, as
In practice, "nonmammal" is used in discussions of ecology, paleontology, or education to contrast with mammals.