metazoa
Animals, taxonomically speaking
Metazoa is the scientific term for multicellular animals—organisms whose cells are organized into tissues and organs.
The word distinguishes animals from single-celled organisms and from plants or fungi.
In biological classification, metazoa encompasses everything from sponges to humans: The evolution of metazoa began over 600 million years ago.
The singular is metazoan. (Capitalized Metazoa is the formal taxonomic name.)
Having multiple cells
- eukaryoticHaving organized nuclear membrane
- tissuesSoft disposable paper sheets
- organsFunctional body parts
- heterotrophicRequiring organic sustenance
motility · nervous system · digestive system · reproduction · sexual reproduction · animals · organisms · creatures
Animals with internal skeletons
- invertebratesAnimals without vertebral columns
- mammalsHair-bearing, milk-producing animals
- reptilesCold-blooded scaly vertebrates
- amphibiansVertebrates with aquatic larvae
birds · fish · arthropods · mollusks · echinoderms · nematodes · flatworms · annelids
Sudden appearance of complex life
- phylogenyEvolutionary relationships among organisms
- common ancestorOrigin point of descendants
- fossilsPreserved ancient organism traces
- paleontologyStudy of ancient organisms
speciation · adaptation · natural selection · homology · divergence · radiation · extinction · Burgess Shale
Interconnected predator-prey relationships
- predatorOrganism that consumes others
- preyAnimal being hunted
- herbivorePlant-only consumer
- carnivoreCreature eating only animals
omnivore · decomposer · symbiosis · parasitism · migration · habitat · population · consumer
multicellular
Having multiple cells
- eukaryoticHaving organized nuclear membrane
- tissuesSoft disposable paper sheets
- organsFunctional body parts
heterotrophic · motility · nervous system · digestive system · reproduction · sexual reproduction · animals · organisms · creatures
vertebrates
Animals with internal skeletons
- invertebratesAnimals without vertebral columns
- mammalsHair-bearing, milk-producing animals
- reptilesCold-blooded scaly vertebrates
amphibians · birds · fish · arthropods · mollusks · echinoderms · nematodes · flatworms · annelids · chordates
Cambrian explosion
Sudden appearance of complex life
- phylogenyEvolutionary relationships among organisms
- common ancestorOrigin point of descendants
- fossilsPreserved ancient organism traces
paleontology · speciation · adaptation · natural selection · homology · divergence · radiation · extinction · Burgess Shale · bilateral symmetry
food web
Interconnected predator-prey relationships
carnivore · omnivore · decomposer · symbiosis · parasitism · migration · habitat · population · consumer · pollinator
metazoaprotozoa
Single-celled eukaryotic organisms
unicellular organisms · single-celled organisms · protists · protozoans · amoeba