1.1.1.1.1. They may not have tissues, but they do have layers of cells that classify them as animals.

They are carnivores that tend to have tentacles around their mouth to catch their prey.

The diversity is shown through the number of animal phyla in the group: 18 animal phyla. This is more than twice the number of any other group.

It contains more species than all other plant, protist, animal, and fungus groups combined.

This is because molecular evidence indicates that some animal phyla from other groups could technically be classified into this group.