Page 11 - Science Course 2 (Book 1)

Mo1-L1a: How are Animals Classified?

Animals then are classified into phyla (singular,
phylum), genera (singular, genus), and species. Key Concept
How are Animals Classified?
Domain How do scientists group animals?

Kingdom

Phylum

Class

Order

Family

Genus

Species

Scientists organize animals into groups based on characteristics they have in common. This tree diagram
shows the relationships among animal groups based on common characteristics.

Segmented worms

Mollusks Arthropods Echinoderms

Roundworms

Flatworms Radial symmetry
as adults Chordates
Cnidarians

Sponges

Radial symmetry

Tissue layers, body cavity, bilateral symmetry
Tissues
Multicellular

SUMMARY
How are Animals Classified?
Animals are multicellular, have nerve cells,
and cannot change light energy into food
energy.
One way to group animals is by their
symmetry.

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