> Eudora
> Our Universe
> Galaxies
> Individual Galaxies
> Milky Way
> Spiral Arms of the Milky Way
> Orion–Cygnus Arm
> Individual Planetary & Star Systems in the Orion-Cygnus Arm
> Solar System
> Objects in the Solar System
> Planets of the Solar System
> Individual Planets in the Solar System
> Earth
> Chronology of Earth
> History of the Earth
> Evolution of Life
> Tree of Life on Earth
> Domains, Species Kingdoms etc.
> Node
> Eukaryota
> Unikonta
> Opisthokonta
> Holozoa
> Filozoa
> Node
Eumetazoa
Animal. Most known animal phyla appeared in the fossil record as marine species during the Cambrian explosion, about 542 million years ago.
Animals are divided into various sub-groups, some of which are: vertebrates (birds, mammals, amphibians, reptiles, fish); mollusks (clams, oysters, octopuses, squid, snails); arthropods (millipedes, centipedes, insects, spiders, scorpions, crabs, lobsters, shrimp); annelids (earthworms, leeches); sponges; and jellyfish. Etymology.
