Animals – Kingdom Animalia

WRITTEN BYLeigh M. Van ValenSee All ContributorsProfessor of Ecology and Evolution, University of Chicago.See Article History

Alternative Title: Animalia

Animal, (kingdom Animalia), any of a group of multicellular eukaryotic organisms (i.e., as distinct from bacteria, their deoxyribonucleic acid, or DNA, is contained in a membrane-bound nucleus). They are thought to have evolved independently from the unicellular eukaryotes.