User:Caehlla2357/sandbox/Animal (independent)

Characteristics
Animals are eukaryotes that are multicellular and heterotrophic; they cannot make their own food and must ingest it. Most animals can move and sense their environment, and with exceptions such as sponges and jellyfish, have nervous tissue and muscle tissue. Most animals require oxygen to live; however, few of them do not.

Evolutionary history
Molecular clock estimates for the origin of animals